Astronomy & Astrophysics manuscript no. PKS2155˙astroph˙erratum c© ESO 2018
October 25, 2018
REM near-IR and optical multiband observations of
PKS 2155-304 in 2005⋆
A. Dolcini1, F. Farfanelli2, S. Ciprini2, A. Treves1, S. Covino3, G. Tosti2, E. Pian4, B. Sbarufatti1, E. Molinari3, G.
Chincarini3 ,5, F. M. Zerbi3, G. Malaspina3, P. Conconi3, L. Nicastro6, E. Palazzi6, V. Testa7, F. Vitali7, L. A.
Antonelli7, J. Danziger4, G. Tagliaferri3, E. Meurs8, S. Vergani8, A. Fernandez-Soto9 , E. Distefano10, G.
Cutispoto10, and F. D’Alessio7
1 Università degli Studi dell’Insubria, Dipartimento di Fisica e Matematica, via Valleggio 11, 22100 Como, Italy
2 Dipartimento di Fisica e Osservatorio Astronomico, Università di Perugia, Via. A. Pascoli, 06123 Perugia, Italy
3 INAF, Osservatorio Astronomico di Brera, via E. Bianchi 46, 23807 Merate (LC), Italy
4 INAF, Osservatorio Astronomico di Trieste, Via G. B. Tiepolo 11, 34143 Trieste, Italy
5 Università degli Studi di Milano-Bicocca, Dipartimento di Fisica, Piazza delle Scienze, 3, 20126 Milan, Italy
6 INAF/IASF Bologna, via Gobetti 101, 40129 Bologna, Italy
7 INAF, Osservatorio Astronomico di Roma, via Frascati 33, 00040 Monteporzio Catone, Italy
8 Dunsink Observatory, Castleknock, Dublin 15, Ireland
9 Observatori Astronomic, Universitat de Valencia, Aptdo. Correos 22085, Valencia 46071, Spain
10 INAF, Osservatorio Astrofisico di Catania, via S. Sofia 78, 95123 Catania, Italy
Received 29 September 2006 / Accepted 26 March 2007
Abstract
Context. Spectral variability is the main tool for constraining emission models of BL Lac objects.
Aims. By means of systematic observations of the BL Lac prototype PKS 2155-304 in the infrared-optical band, we explore variability on the
scales of months, days and hours.
Methods. We made our observations with the robotic 60 cm telescope REM located at La Silla, Chile. VRIJHK filters were used.
Results. PKS 2155-304 was observed from May to December 2005. The wavelength interval explored, the total number of photometric points
and the short integration time render our photometry substantially superior to previous ones for this source. On the basis of the intensity and
colour we distinguish three different states of the source, each of duration of months, which include all those described in the literature. In
particular, we report the highest state ever detected in the H band. The source varied by a factor of 4 in this band, much more than in the V band
(a factor ≈ 2). The source softened with increasing intensity, contrary to the general pattern observed in the UV-X-ray bands. On five nights of
November we had nearly continuous monitoring for 2-3 hours. A variability episode with a time scale of τ ≈24 h is well documented, a much
more rapid flare with τ=1-2 h, is also apparent, but is supported by relatively few points.
Conclusions. The overall spectral energy distribution of PKS 2155-304 is commonly described by a synchrotron-self-Compton model. The
optical infrared emission is however in excess of the expectation of the model, in its original formulation. This can be explained by a variation
of the frequency of the synchrotron peak, which is not unprecedented in BL Lacs.
Key words. galaxies: active - galaxies: BL Lacertae objects: PKS 2155-304
1. Introduction
PKS 2155-304 (z=0.116, Falomo et al. 1991) is a prototype of high frequency peaked BL Lac objects. It has been observed in
the entire electromagnetic spectrum, from radio to TeV gamma-rays. It was the target of several multifrequency campaigns, the
main scope of which was to study the variability of the spectral energy distribution (SED), in order to constrain emission models.
In particular we refer to the 1991 and 1994 campaigns involving IUE, ROSAT, ASCA, EUVE and ground based telescopes
(see Edelson et al. 1995, Urry et al. 1997, and references therein). There were noticeable differences in source behaviour between
these two epochs. While in 1991 the multiwavelength variability was almost achromatic, and the X-ray variation led that in the
UV by a couple of hours, in 1994 the variability was more pronounced in X-rays than in UV-optical, with a lag of the latter
⋆ This paper is the corrected version astroph 0704.0265 published in A&A 469 503. It contains the material in the ”Errata Corrrige”, in press
in A&A.
http://arxiv.org/abs/0704.0265v2
2 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
Period of observation Nights of observation Number of photometric points Total exposure time
May 6 129 14520 s
September 8 159 18080 s
October 3 102 11590 s
November 21 1581 173540 s
December 6 64 7030 s
Table 1. Outline of observations accomplished in 2005.
by two days. The general pattern was that of a hardening of the spectrum with increasing intensity. More recently Zhang et al.
(2006b) studied a large set of data covering the period 2000-2005 obtained with the XMM-Newton satellite, which allowed a
direct comparison of the X-ray and UV-optical band, the latter deriving from the Optical Monitor on board the satellite. The
complexity of the variability pattern is confirmed. Some episodes of achromatic variation were detected, but a general tendency
of increasing variability amplitude with increasing frequency, and spectral hardening with increasing intensity was found.
Optical photometry has been performed by several groups in several occasions (see e.g. Miller et al. (1983), Smith et al.
(1992), Xie et al. (1996), Paltani et al. (1997), Pesce et al. (1997), Fan & Lin (2000), Tommasi et al. (2001) and references
therein). All this material is rather fragmented, consisting of few hours of observations during few nights. The difficulty of a
systematic observing campaign covering many nights is partly overcome by the possibility of observing using remotely guided
or robotic telescopes.
The REM telescope, originally designed for a prompt detection of gamma ray bursts (see Molinari et al. (2006)), is particularly
apt for photometric studies of BL Lacs (see also the previous results for PKS 0537-441 by Dolcini et al. 2005, and for 3C 454.3
by Fuhrmann et al. 2006) and, being located at La Silla (Chile), it is ideally fit to study PKS 2155-304.
We report on extensive and intensive photometric campaign performed in 2005 in the V, R, I, J, H, K bands. For the total
number of photometric points, for the time resolution (minutes) and spectral range this campaign seems to supersede all the
IR-optical photometric material presented thus far.
2. REM, Photometric procedure, data analysis
2.1. REM
The Rapid Eye Mount (REM) Telescope is a 60 cm fully robotic instrument. It has two cameras fed at the same time by a dichroic
filter that allows the telescope to observe in the NIR (z’, J, H, K) as well as optical (I, R, V). Further information on the REM
project may be found in Zerbi et al. (2001), Chincarini et al. (2003) and Covino et al. (2004).
2.2. Observations and data analysis
REM observed the PKS 2155-304 field during May, September, October, November and December 2005 in VRIH bands. Only
during three nights in September the telescope observed also in J and K filters. To allow intranight and short time-scale variability
monitoring, very intensive observations (2-3 h, quasi-continuously) were made during five of the nights in November. An outline
of the observations is reported in Table 1, while the complete log is only available in Table A.1 (see Appendix A): we report for
each photometric point the band, the epoch, the integration time, the intensity and its uncertainty. Typical integration times are
≤100 s and statistical uncertainties are always ≤ 10% and ≤ 3% in the highest state (November 2005, see following).
Reduction of the REM NIR and optical frames followed standard procedures. Photometric analysis of the frames was done
using the GAIA1 and DAOPHOT packages (Stetson 1986). Relative calibration was obtained by calculating magnitude shifts
relative to three bright isolated stars in the field, indicated by A, B, C in Fig. 1 (image taken from ESO Digitized Sky Survey2).
The NIR frames were calibrated using the magnitudes of the A, B and C stars as reported in the 2MASS catalogue3. For the
optical, we exposed on 2006 June 29 the standard field G156-31 (Landolt, 1992), and immediately after this the PKS 2155-304
field. We calculated the zero points which were then used to calibrate all of our data. The observed magnitudes in the REM filters
for the reference objects A, B, and C are reported in Table 2. We have monitored the relative intensities of the A, B, C reference
stars during the entire observation period, and we have detected no indication of variability within 0.1 mag (error on the average
≤0.01 mag).
1 http://star-www.dur.ac.uk/ pdraper/gaia/gaia.html
2 http://archive.eso.org/dss/dss
3 http://irsa.ipac.caltech.edu
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 3
Figure 1. PKS2155-304 field (DSS-1 survey). Letters indicate stars used for calibration.
A B C
RA 21:58:46.505 21:58:43.807 21:58:42.337
DEC -30:17:51.29 -30:17:15.71 -30:10:27.41
K 11.171±0.024 12.475±0.030 12.648±0.024
H 11.182±0.027 12.556±0.026 12.769±0.027
J 11.510±0.027 12.838±0.026 13.091±0.029
I 12.184±0.005 13.421±0.009 13.216±0.006
R 12.981±0.004 13.434±0.006 13.671±0.010
V 13.179±0.005 13.822±0.009 13.899±0.013
Table 2. Coordinates, IR and optical magnitudes for the reference stars.
Note that we found significant deviations from the optical calibrations provided by the finding charts for AGN of the
Heidelberg University4 (Hamuy & Maza, 1989). In particular the star C is also used as a calibrator by these authors and our
optical zeropoint differs by about 0.3 mag from theirs.
Relative and absolute calibration errors have been added in quadrature to the photometric error derived from the procedure.
3. Results
3.1. Long term variability
In this section we report the results of the long term photometric analysis. The light curves in the H, R, I, V filters are given in
Fig. 2.
The intensity is normalized with respect to the average over the entire observation period. These averages are given in Table
3. It is immediately apparent that the total variability range is very different in the various filters, being a factor ≈ 4 in H and a
factor ≈ 2 in V (see Table 3) . The shapes of the light curves are similar in the various filters. A flare-like structure is apparent
in all filters at t ≈ 680 (first days of November). The ratio between the V- and H-band fluxes, designated as V/H, is reported in
Fig. 3. In order not to introduce spurious effects due to small time scale variability, the V/H ratio has been computed for pairs of
V and H measurements spaced apart in time by no more than 10 minutes.
It seems that there are two main colour states: the source softens rather abruptly, in response to the November flare. On
the basis of the light curve and the colour curve we divide the observations in three epochs: 1 500-525, 2 640-660, 3 670-725,
expressed in MJD5.
4 http://www.lsw.uni-heidelberg.de/projects/extragalactic/charts/2155-304.html
5 For the Modified Julian Date we use the convention MJD=JD-2,453,000.5
4 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
500 550 600 650 700
500 550 600 650 700
500 550 600 650 700
H filter
I filter
R filter
V filter
500 550 600 650 700
Figure 2. Normalized light curves of PKS 2155-304. Flux is reported in arbitrary unit (a. u.). In each boxes a typical error bar is
plotted.
Filter H I R V
Average 114.9±3.3 34.45±6.5 30.89±5.13 30.70±5.05
Max value 156.5 46.4 38.3 37.4
Min value 36.5 19.1 16.2 16.2
Average ep.1 39.3±1.4 21.4±1.5 18.7±1.3 18.1±0.7
Average ep.2 65.9±5.2 28.4±3.3 27.2±2.5 20.3±3.4
Average ep.3 122.9±6.1 38.8±1.9 34.1±1.5 33.5±1.7
Table 3. Average intensities for all epochs and all filters. All data are in mJy units. Epoch 1 corresponds to May 2005 observa-
tions, epoch 2 to September-October 2005 observations and epoch 3 to November-December 2005 observations.
3.2. Short time-scale variability
We report in Fig. 4 the light curves for five nights in November 2005, when the observations were more intensive. All the nights
belong to epoch 3, corresponding to the high state of the source.
The mean intensity and the 1-sigma values for each night are given in Table 4.
A χ2 analysis indicates that in each night the significance of variability is very high, but for the nights of Nov 4 and Nov 18
for the H band and Nov 19 for the V band. In the box of Nov 4 - V band we also report the photometry of a comparison star
which illustrates directly the significance of the source variability. Though the shapes of intensity curves are different (see Fig.
4), there is a rather regular colour-intensity dependence (see Fig. 5) indicating harder states for higher intensities.
We adopt the usual definition of time scale variability τ = 11+z
d f/dt . Following Montagni et al. (2006), a variability time scale
is taken as reliable if the light curve can be approximated with a linear dependence, and it contains at least 10 points. In particular
this gives a time scale of ≈ 24 h for the November 4 night (Fig. 4, V band - Nov 4 box). The simultaneous H light curve does
not show any regular variability. We note that on November 8 in the H curve there is a flare-like event. If one connects 4 points
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 5
Time (MJD)
500 525 550 575 600 625 650 675 700 725
Figure 3. V/H flux ratio evolution during 2005. Error bars are comparable with symbol size.
Figure 4. Light curves in the H and V filters for five nigths in November 2005, when the observations were more intensive. Dates
of observations are reported in each box. The solid line in V band - 4 Nov box results from a linear regression analysis. The solid
line in H band - 8 Nov box connects the four points of the flare-like structure. In each box it is given a typical error bar. In V
band - 4 Nov box the light curve of one comparison star is also plotted, with a fixed enhancement of 9 mJy.
6 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
Figure 5. V/H flux ratio versus intensity for the five more intensively observed nights of epoch 3. In each box a typical error bar
is plotted.
Night 4/11 8/11 18/11 19/11 20/11
Average H 119.3±1.7 119.3±3.0 120.4±2.1 124.5±2.8 130.8±3.0
Average I 39.1±0.6 36.4±0.5 38.7±0.6 38.7±0.6 38.3±0.7
Average R 38.5±0.8 36.40±.8 37.3±0.5 38.0±1.6 37.1±0.5
Average V 33.2±1.1 33.0±1.1 33.4±1.1 33.5±1.1 34.7±0.1
Table 4. Average intensities and 1-sigma values for all filters for all five nights with more intensive observations in November
2005. All values are in mJy units.
as suggested in Fig. 4 H band - Nov 8 box, the time scale variability is as short as 1.5 h. Unfortunately the V light curve is too
sparse to confirm the presence of the flare also in this band.
3.3. The NIR-Optical spectral energy distribution
We had six filter coverage (K,H,J,I,R,V) during three nights of Sept. 2005 (epoch 2) and representative SEDs for these nights are
reported in Fig. 6.
The delays between exposures in the different filters are less than 20 minutes. Reddening corrections are less than 6% in V
and have been neglected. A fit with a single power law yields α ≈0.9 and it is clearly not good. The main deviation derives from
the J filter, exceeding substantially our photometric precision of about 10%. An improvement in the fit is obtained by using a
broken power law with spectral indices α ≈0.4 for the IR data and α ≈0.9 for the optical data.
For comparison, we report in Fig. 7 the SED of June 29, 2006, exposure used for calibration purpose: its profile is rather
similar to that of Sept. 2005.
At the other epochs the SED consists of 4 points (H, I, R, V), and in Figs. 8 and 10 we give representative examples of SEDs
acquired on epoch 1 and 3. The time differences between observations at various filters are less than 20 minutes.
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 7
Frequency (Hz)
19/9 data
21/9 data
26/9 data
Average data
Figure 6. September 2005 spectra for observations including the K and J filters. The spectral fit on average data with a single
power law yields a spectral index α=0.91±0.07.
Frequency (Hz)
Figure 7. 29 June 2006 spectrum. The spectral fit with a single power law yields a spectral index α=0.90±0.16.
In Fig. 8, which refers to a low state, we report also the estimated contribution of the host galaxy, which was calculated
adopting the H magnitude of the galaxy measured by Kotilainen et al. (1998) and the Mannucci at al. (2001) template spectrum
for giant ellipticals. It is apparent that the contribution of the galaxy never exceeds 20% of the BL Lac signal. At the other epochs
the contribution from galaxy is negligible and it is not relevant for explaining the excess in J with respect a single power law
noted above. The epoch 2 photometry (Fig. 9) is compared with spectrophotometry obtained with the ESO 3.6m telescope by R.
Falomo6 on July 25, 2001 (Sbarufatti et al. (2006)). The source was found in a similar, but somewhat lower brightness state and
some deviations from a power law are apparent. The HRIV points at epoch 3 (Fig. 10) are roughly fitted by a single power law
of α ≈1.3. In any case the comparison of the SEDs at the three epochs clearly indicate a softening with increasing intensity.
6 spectrum available at the ZBLLAC online library, http://www.oapd.inaf.it/zbllac
http://www.oapd.inaf.it/zbllac
8 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
Figure 8. 13 May 2005 spectrum - epoch 1. We report also the spectrum of the host galaxy (see text). The spectral fit with a
single power law yields a spectral index α=0.77±0.16.
Figure 9. 19 September 2005 spectrum - epoch 2. For comparison we report the ESO 3.6m telescope spectrophotometry which
correspond to a slightly lower state of the source. The spectral fit with a single power law yields a spectral index α=0.88±0.05.
4. Discussion
A collection of near-IR/optical SEDs of PKS2155-304 obtained by various authors at different epochs is presented in Fig. 11 and
in Table 5. Our data encompass all those reported in the literature.
In the historical observations of PKS2155-304 the delays between exposures at different filters are typically of the order of
hours, instead of about 10 minutes as in our data set. Comparing literature data with our data it is apparent that the maximum
we observed on 20 November 2005 in the H filter light curve is the highest state ever reported in this band. Note that the V state
was comparable with states reported in the literature, likely because the coverage of the source in the optical band is less sparse
than that in the NIR. A most noticeable result of our photometry is the discovery of long term H-band variability, the amplitude
of which is much larger than that in the optical.
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 9
Frequency (Hz)
Figure 10. 4 November 2005 spectrum - epoch 3. The spectral fit with a single power law yields a spectral index α=1.32±0.25.
Error bars are comparable with symbols size.
Data set α V (mJy)
This work (13/5/2005) 0.77±0.16 16.485±0.263
This work (19/9/2005) 0.88±0.05 24.370±0.238
This work (4/11/2005) 1.32±0.24 35.278±0.498
Bertone at al. (2000) 0.42±0.26 26.20±0.58
Pesce et al. (1997) 0.62±0.30 24.50±0.67
Zhang & Xie (1996) 0.62±0.16 22.90±0.63
Bersanelli et al. (1992) 0.61±0.38 51.88±1.56 (J band)
Treves et al. (1989) (1/12/1983) 0.51±0.31 19.80±0.36
Treves et al. (1989) (11/11/1984) 0.51±0.41 26.20±0.48
Miller & McAlister (1983) 0.62±0.56 17.8
Table 5. Spectral index values and V values for all spectra plotted in Fig. 11. α vs V plot is reported in Fig. 12.
In Fig. 12 we plot the spectral index vs the V magnitude, as reported in table 5. There is no apparent correlation. It is
noticeable however that the highest state in all bands (our observation of Nov 2005) corresponds to a rather soft spectral shape.
This contrasts with the usual source behaviour of hardening with increasing intensity, as found in the UV-X-ray band (see
Introduction). It contrasts also with the short time scale variability, as reported in section 3.2.
There is a general consensus that the blazar SED can be explained by the superposition of a synchrotron component, and
an inverse Compton one due either to scattering off the synchrotron photons (synchrotron-self Compton, SSC), or to external
photons like those of the broad line region or of a thermal disk (e.g. Tavecchio et al. 1998, Katarzynski et al. 2005). This results
in a typical two-maxima shape of the blazar SED. In Fig. 13 we report examples of the SED modeling proposed for PKS 2155-
304, on the basis of data taken in 1997. The models are detailed in Chiappetti et al. (1999). The object is a typical HBL, with the
synchrotron peak in the soft X-rays.
A well known critical point of this model, is that the source size is essentially constrained by variability, and variability itself
requires that the SED is constructed using simultaneous observations in all bands. A further step of the modelling consists in
identifying the physical origin of the relativistic jet and of its variability, see e.g. Katarzynski & Ghisellini (2006). With this
premise it is obvious that the optical-IR photometric study, non simultaneous with that in other regions of the SED, has only a
limited relevance in clarifying the overall picture. However we would like to make some remarks. If the SSC models reported in
Fig. 13 truly represent the behaviour of the SED in 1997, as suggested by the good match with the X-ray and TeV energy data,
and if our 2005 optical-IR spectra are also due to the SSC mechanism, then the latter represent a different condition in the jet
and point to different critical parameters within the SSC scenario. While the IR-optical spectrum in May 2005 (triangles) has
the same shape as predicted in 1997, but different normalization, the November 2005 IR-optical spectrum is different in both
10 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
This work (13/5/2005)
This work (19/9/2005)
This work (4/11/2005)
Bertone et al. 2000 (24/5/1996)
Pesce et al. 1997 (19/5/1994)
Zhang and Xie 1996 (5/7/1994)
Bersanelli et al. 1992 (17/1/1987)
Treves et al. 1989 (1/12/1983)
Treves et al. 1989 (11/11/1984)
Miller and McAlister 1983 (19/11/1981)
Frequency (Hz)
Figure 11. Different spectra of PKS2155-304 from observations at other epochs reported in the literature. Symbols correspond
to following works: filled circles: this work (13/5/2005 data), filled squares: this work (19/9/2005 data), filled up triangles: this
work (4/11/2005 data), open diamonds: Bertone et al. (2000; 24/5/1996 data), open circles: Pesce et al. (1997; 19/5/1994 data,
the Hamuy & Maza (1989) calibration is used), open up triangles: Zhang and Xie (1996; 5/7/1994 data), open squares: Bersanelli
et al. (1992; 17/1/1987 data), open crosses: Treves et al. (1989; 1/12/1983 data), open stars: Treves et al. (1989; 11/11/1984 data),
asterisks: Miller and McAlister (1983; 19/11/1981 data). Spectral index values and V magnitudes for all data sets are reported in
Table 5.
shape and normalization. The May 2005 observation suggests that the synchrotron peak may be located at a frequency similar to
the one observed in 1997 (approximately between extreme UV and soft X-rays), the total energy being somewhat higher (about
a factor 2, see Figure 13) than observed in 1997. The slope of the November 2005 spectrum suggests instead a much lower
synchrotron peak energy, around the IR-optical domain or even redward, i.e. about 2-3 orders of magnitude lower than observed
in 1997 and inferred in May 2005. While a variation of the synchrotron peak energy of this amplitude and on this time scale
(the September 2005 slope is intermediate between those of May and November 2005, suggesting a monotonic change) it is not
unprecedented in blazars (Mkn501 exhibited a similar variation in a much more rapid time scale, Pian et al. 1998), this would be
the first observation of this kind in PKS 2155-304. Therefore, our interpretation is only tentative, although supported by the large
observed IR variability.
Alternatively, in order to explain the optical-IR flux excess we observe in 2005 with respect to the SSC prediction based on
the earlier multiwavelength data (Fig. 13), one could invoke a thermal component, possibly from hot dust associated with the
“dusty torus” surrounding the central region of the active nucleus, as suggested in the cases of other blazars with excess in the
optical-infrared band (De Diego et al. 1997, for blazar 3C 66A; Pian et al. 1999 for 3C 279; Pian et al. 2002, 2006, for blazar
PKS 0537-441). However, this seems somewhat less likely, because high emission states, as observed by us, are expected to be
dominated by non-thermal beamed relativistic radiation.
The continuation of this and other similar optical-IR studies, which have been proven to be promising but do not provide
enough information for a physical interpretation of the data, requires that the observations are extended to other wavelengths.
Simultaneous observations over a large wavelength range is the only tool to provide the necessary information for a physical
interpretationof the observed variability of blazars. REM monitorings of the kind reported here could be an effective trigger to
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 11
V (mJy)
15 17.5 20 22.5 25 27.5 30 32.5 35
Figure 12. α vs V plot for data reported in Fig. 11. Symbols are the same as used in Fig. 11.
X-ray satellites, and programs along these lines are foreseen with SWIFT. Cross correlation procedures, which up to now have
been limited mainly to the X-ray band (Zhang et al. 2005, 2006a, 2006b, Sembay et al. 2002, Edelson et al. 1995), would be
extended to a much larger portion of the SED.
Appendix A: Table of observations
Filter Epoch (MJD) Integr time s Intensity mJy Sigma
K 633.4872 120 73.993 3.640
K 633.4966 120 73.345 3.640
K 633.5012 120 73.382 2.938
K 633.5094 120 76.417 1.043
K 633.5254 120 72.309 2.698
K 635.4835 120 70.598 2.579
K 635.6612 120 66.373 2.810
K 635.6670 120 67.794 2.548
K 635.6736 120 67.857 2.096
K 635.6794 120 69.182 2.758
K 635.6832 120 66.987 2.263
K 639.8339 120 67.982 0.689
K 639.8355 120 67.345 0.702
H 503.7708 120 38.943 3.048
H 503.7723 120 39.412 2.977
H 503.7741 120 38.907 2.903
H 503.8028 120 40.628 3.180
H 503.8043 120 43.135 7.497
H 507.7738 120 38.373 0.314
H 507.7753 120 38.302 0.314
H 507.7839 120 38.692 0.317
H 507.7854 120 38.586 0.316
12 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 507.7873 120 38.835 0.601
H 507.7881 120 38.871 0.318
H 508.7487 120 37.881 1.999
H 508.7501 120 37.224 2.168
H 508.7516 120 37.771 2.127
H 508.7531 120 38.444 1.924
H 508.7549 120 37.847 1.146
H 508.7565 120 37.396 1.786
H 510.6465 120 39.339 2.005
H 510.7174 120 39.850 1.559
H 510.7192 120 39.557 1.584
H 510.7208 120 39.594 1.513
H 510.7229 120 40.274 1.466
H 510.7244 120 40.071 1.240
H 510.7379 120 39.484 1.258
H 510.7394 120 39.740 1.555
H 510.7413 120 39.960 1.382
H 510.7427 120 39.412 1.399
H 510.7448 120 40.219 2.635
H 510.7463 120 40.256 1.246
H 514.7073 120 38.799 1.271
H 514.7089 120 38.056 1.247
H 514.7107 120 38.515 1.297
H 514.7122 120 38.267 1.741
H 514.7143 120 37.881 1.379
H 514.7156 120 38.887 1.415
H 514.7068 120 37.881 2.448
H 514.7710 120 37.812 1.342
H 514.7734 120 37.259 1.288
H 514.7749 120 36.478 1.162
H 515.6989 120 40.929 2.272
H 515.7003 120 40.108 2.117
H 515.7022 120 40.966 2.833
H 515.7037 120 41.155 2.210
H 515.7085 120 40.703 3.926
H 515.7086 120 41.422 2.149
H 515.7091 120 41.042 2.316
H 515.7106 120 41.117 2.320
H 515.7124 120 41.498 2.266
H 515.7139 120 40.816 2.117
H 635.3400 120 61.436 2.148
H 635.3489 120 63.801 0.405
H 635.3552 120 63.566 0.794
H 635.3648 120 62.349 0.855
H 637.5426 120 57.494 0.952
H 637.5481 120 57.334 1.721
H 637.5502 120 57.230 1.591
H 637.5619 120 55.928 1.162
H 637.5779 120 55.671 1.427
H 642.6039 120 59.597 1.427
H 642.6054 120 59.597 1.394
H 643.4546 120 61.267 0.902
H 643.4561 120 61.948 0.509
H 643.4581 120 62.119 1.031
H 643.4596 120 62.925 1.627
H 643.4607 120 61.663 0.741
H 643.4631 120 62.607 0.992
H 645.5581 120 64.095 1.014
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 13
H 645.5622 120 65.528 1.049
H 645.5641 120 64.036 1.104
H 645.5655 120 63.860 2.105
H 646.4435 120 60.873 2.048
H 646.4464 120 60.817 2.036
H 646.4490 120 60.482 2.044
H 646.4510 120 60.705 3.685
H 646.4521 120 62.291 2.194
H 646.4536 120 61.834 3.389
H 650.5509 120 64.213 2.708
H 650.5524 120 66.134 2.500
H 650.5537 120 64.036 3.012
H 650.5552 120 62.810 5.245
H 650.5571 120 65.047 3.372
H 650.5586 120 64.629 2.247
H 650.5606 120 63.449 2.176
H 650.5621 120 65.770 2.425
H 650.5641 120 66.256 2.454
H 650.5709 120 64.808 4.160
H 650.5743 120 64.692 2.418
H 655.3672 120 73.253 2.759
H 655.3688 120 72.048 1.800
H 655.3708 120 71.322 1.508
H 655.3716 120 71.916 1.493
H 655.3741 120 71.718 1.505
H 655.3756 120 73.312 1.762
H 655.3772 120 71.454 1.996
H 655.3787 120 71.257 1.886
H 655.5449 120 71.652 1.500
H 655.5464 120 71.652 1.695
H 655.5481 120 70.474 1.475
H 655.5496 120 70.799 1.482
H 655.5515 120 71.191 1.490
H 655.5530 120 71.718 1.501
H 655.5548 120 72.115 1.641
H 655.5563 120 71.718 1.566
H 655.5581 120 72.381 2.305
H 655.5596 120 72.448 1.516
H 655.5615 120 71.536 1.562
H 655.5630 120 71.060 1.552
H 655.5648 120 71.652 1.565
H 655.5663 120 71.454 1.561
H 655.5681 120 71.119 1.620
H 655.5696 120 70.799 2.577
H 665.3660 120 118.912 3.138
H 678.3451 120 121.458 1.503
H 678.3466 120 116.957 1.524
H 678.3480 120 117.173 1.628
H 678.3501 120 121.458 1.687
H 678.3516 120 120.455 1.491
H 678.3531 120 121.570 1.689
H 678.3551 120 117.497 1.821
H 678.3566 120 120.123 3.080
H 678.3581 120 119.902 1.562
H 678.3604 120 121.123 2.447
H 678.3619 120 117.822 1.971
H 678.3634 120 119.131 1.601
H 678.3656 120 120.012 1.932
14 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 678.3671 120 119.571 1.661
H 678.3685 120 119.022 2.584
H 678.3707 120 119.681 1.927
H 678.3723 120 117.065 1.885
H 678.3738 120 117.931 1.460
H 678.3759 120 118.366 1.500
H 678.3774 120 118.584 1.593
H 678.3788 120 118.366 1.767
H 678.3811 120 118.803 1.506
H 678.3826 120 118.803 1.470
H 678.3840 120 118.803 1.470
H 678.3862 120 117.822 1.493
H 678.3877 120 118.693 2.064
H 678.3892 120 117.931 1.760
H 678.3911 120 117.931 1.638
H 678.3926 120 119.022 1.653
H 678.3942 120 119.902 1.790
H 678.3963 120 118.475 1.466
H 678.3978 120 118.039 1.461
H 678.3993 120 118.257 1.765
H 678.4014 120 118.039 1.461
H 678.4028 120 117.605 1.968
H 678.4043 120 118.912 1.472
H 678.4064 120 120.123 1.728
H 678.4078 120 121.123 1.499
H 678.4093 120 119.792 2.164
H 678.4114 120 118.584 2.225
H 678.4128 120 117.281 1.528
H 678.4143 120 117.281 2.457
H 678.4164 120 117.497 1.754
H 678.4178 120 115.140 1.500
H 678.4193 120 119.022 1.776
H 678.4214 120 117.822 1.535
H 678.4218 120 118.257 1.643
H 678.4244 120 115.352 1.503
H 678.4265 120 118.912 1.711
H 678.4280 120 116.098 1.437
H 678.4294 120 120.900 1.496
H 678.4346 120 119.131 1.601
H 678.4362 120 120.677 2.019
H 678.4376 120 120.677 1.494
H 678.4398 120 120.789 1.495
H 678.4412 120 120.566 3.387
H 678.4427 120 121.123 2.359
H 678.4447 120 122.019 1.891
H 678.4462 120 120.789 1.495
H 678.4476 120 120.344 2.092
H 678.4497 120 120.900 2.811
H 678.4512 120 121.794 2.372
H 678.4526 120 121.794 2.372
H 678.4546 120 120.012 2.605
H 678.4562 120 120.566 3.189
H 678.4576 120 121.906 1.693
H 678.4597 120 121.458 1.882
H 678.4612 120 122.582 2.214
H 678.4626 120 121.794 1.887
H 682.3480 120 118.693 1.260
H 682.3495 120 117.497 1.152
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 15
H 682.3510 120 116.634 3.660
H 682.3532 120 119.681 1.270
H 682.3547 120 119.681 1.270
H 682.3562 120 119.131 3.121
H 682.3583 120 119.351 1.170
H 682.3597 120 117.822 1.155
H 682.3618 120 118.693 1.163
H 682.3633 120 118.257 1.851
H 682.3647 120 118.257 1.159
H 682.3669 120 118.366 2.313
H 682.3684 120 117.173 1.192
H 682.3700 120 116.420 1.575
H 682.3721 120 116.420 1.184
H 682.3735 120 118.803 1.689
H 682.3771 120 116.527 3.454
H 682.3771 120 117.389 1.246
H 682.3785 120 117.389 1.246
H 682.3801 120 117.497 1.928
H 682.3821 120 119.681 1.329
H 682.3836 120 120.900 1.556
H 682.3735 120 120.677 1.183
H 682.3872 120 118.148 1.254
H 682.3887 120 119.902 1.175
H 682.3903 120 117.713 1.757
H 682.3917 120 118.693 1.260
H 682.3938 120 117.065 1.747
H 682.3953 120 119.131 2.328
H 682.3968 120 118.148 2.121
H 682.3989 120 116.849 2.006
H 682.4005 120 116.634 2.662
H 682.4019 120 119.131 1.693
H 682.4041 120 121.011 1.284
H 682.4055 120 118.257 2.216
H 682.4070 120 119.351 3.641
H 682.4156 120 120.234 1.547
H 682.4171 120 122.695 2.299
H 682.4186 120 125.900 3.406
H 682.4222 120 132.198 2.373
H 682.4257 120 119.571 3.235
H 682.4271 120 118.693 5.296
H 682.4305 120 120.677 4.421
H 682.4324 120 119.571 3.235
H 682.4338 120 121.011 1.284
H 682.4359 120 117.931 1.310
H 682.4374 120 118.803 1.860
H 682.4388 120 121.682 1.418
H 682.4398 120 123.488 5.620
H 682.4412 120 123.148 1.666
H 682.4427 120 120.012 4.503
H 682.4449 120 119.571 1.464
H 682.4464 120 113.143 1.319
H 682.4479 120 114.189 2.702
H 682.4500 120 120.344 1.549
H 682.4506 120 122.582 1.830
H 682.4543 120 118.039 2.596
H 682.4558 120 126.714 1.551
H 682.4573 120 123.375 7.051
H 683.3333 120 114.611 0.668
16 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 683.3348 120 112.312 1.052
H 683.3363 120 114.717 0.985
H 683.3385 120 112.002 0.653
H 683.3401 120 112.105 0.653
H 683.3415 120 113.560 0.662
H 683.3435 120 113.770 1.442
H 683.3451 120 113.665 0.662
H 683.3466 120 115.885 1.568
H 683.3486 120 113.770 0.809
H 683.3501 120 114.505 0.737
H 683.3516 120 113.665 0.808
H 683.3535 120 113.143 0.804
H 683.3551 120 117.605 0.685
H 683.3566 120 114.400 1.258
H 683.3585 120 115.140 0.671
H 683.3600 120 116.849 0.681
H 683.3616 120 117.065 1.005
H 683.3636 120 112.519 0.656
H 683.3651 120 115.246 0.819
H 683.3666 120 112.830 0.802
H 683.3687 120 115.034 0.818
H 683.3702 120 114.928 0.740
H 683.3717 120 113.979 1.739
H 683.3739 120 114.190 0.812
H 683.3754 120 112.934 0.727
H 683.3769 120 115.565 2.991
H 683.3795 120 112.519 1.054
H 683.3810 120 118.584 0.691
H 683.3826 120 114.400 0.736
H 683.3845 120 112.416 2.109
H 683.3860 120 115.459 0.991
H 683.3875 120 114.084 0.811
H 683.3889 120 115.034 0.740
H 683.3904 120 113.665 0.890
H 683.3920 120 116.527 0.750
H 684.3339 120 120.234 1.488
H 684.3353 120 119.681 1.662
H 684.3368 120 121.123 1.743
H 684.3389 120 119.571 1.558
H 684.3403 120 119.792 1.561
H 684.3441 120 119.681 1.662
H 684.3456 120 122.695 2.570
H 684.3470 120 123.148 1.983
H 684.3484 120 123.148 1.983
H 684.3505 120 119.792 1.929
H 684.3519 120 121.682 1.585
H 684.3541 120 120.900 1.624
H 684.3556 120 122.356 1.700
H 684.3571 120 122.356 1.514
H 684.3591 120 120.123 1.487
H 684.3606 120 120.900 1.532
H 684.3621 120 121.682 2.641
H 684.3644 120 120.789 1.945
H 684.3660 120 121.011 1.577
H 684.3674 120 121.682 3.418
H 684.3696 120 116.205 1.514
H 684.3711 120 122.244 1.698
H 684.3726 120 122.131 2.291
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 17
H 684.3748 120 122.356 1.514
H 684.3762 120 120.234 3.279
H 684.3777 120 123.034 1.653
H 684.3798 120 122.808 2.055
H 684.3813 120 123.034 1.523
H 684.3828 120 124.059 1.536
H 684.3848 120 122.808 1.767
H 684.3863 120 121.906 2.646
H 684.3878 120 124.516 2.896
H 684.3898 120 122.582 1.517
H 684.3912 120 122.019 1.639
H 684.3927 120 122.469 1.596
H 684.3948 120 124.861 1.627
H 684.3962 120 123.602 1.778
H 684.3977 120 121.123 1.808
H 685.3274 120 125.091 1.945
H 685.3289 120 121.346 1.851
H 685.3303 120 127.769 2.978
H 685.3324 120 120.123 1.803
H 685.3409 120 119.792 3.144
H 685.3424 120 116.957 2.644
H 685.3439 120 117.389 2.202
H 685.3459 120 113.770 2.201
H 685.3474 120 117.389 2.202
H 685.3489 120 114.084 2.500
H 685.3510 120 114.506 2.358
H 685.3525 120 118.803 1.888
H 685.3540 120 115.352 2.038
H 685.3561 120 115.992 1.741
H 685.3575 120 116.313 1.746
H 685.3590 120 114.295 1.715
H 685.3610 120 115.459 1.795
H 685.3625 120 117.605 2.206
H 685.3639 120 118.257 3.015
H 685.3660 120 116.527 1.778
H 685.3676 120 119.022 2.451
H 685.3690 120 115.885 2.386
H 685.3711 120 116.420 2.397
H 685.3726 120 115.671 1.838
H 685.3740 120 115.992 1.741
H 685.3761 120 116.527 1.947
H 685.3776 120 119.461 1.793
H 685.3790 120 115.246 1.979
H 685.3810 120 117.822 1.768
H 685.3825 120 114.928 2.223
H 685.3840 120 117.497 1.763
H 689.3300 120 121.682 1.856
H 689.3315 120 120.900 1.844
H 689.3330 120 119.792 1.827
H 689.3351 120 120.344 1.913
H 689.3365 120 116.205 1.995
H 689.3380 120 119.792 1.827
H 689.3401 120 118.039 1.972
H 689.3423 120 120.455 2.723
H 689.3438 120 119.461 1.858
H 689.3458 120 121.794 2.035
H 689.3473 120 119.902 2.003
H 689.3487 120 121.011 2.138
18 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 689.3508 120 119.681 1.861
H 689.3523 120 117.822 1.797
H 689.3537 120 117.931 1.799
H 689.3557 120 123.034 2.055
H 689.3572 120 118.912 4.965
H 689.3586 120 118.584 2.095
H 690.3843 120 135.402 1.676
H 690.3857 120 130.866 8.745
H 690.3892 120 156.468 6.088
H 690.3907 120 133.791 6.165
H 690.3922 120 132.442 1.543
H 690.3943 120 132.809 1.209
H 690.3958 120 131.712 1.072
H 690.3972 120 131.470 1.196
H 690.3994 120 134.408 1.094
H 690.4009 120 136.278 1.109
H 690.4023 120 133.668 3.077
H 690.4044 120 133.545 1.146
H 690.4059 120 136.530 1.111
H 690.4073 120 136.153 1.891
H 690.4094 120 136.781 1.499
H 690.4109 120 132.686 1.207
H 690.4124 120 133.422 1.145
H 690.4144 120 134.532 1.224
H 690.4158 120 135.278 1.393
H 690.4172 120 134.161 1.221
H 690.4193 120 135.902 2.436
H 690.4208 120 134.904 1.158
H 690.4222 120 137.666 2.020
H 690.4244 120 138.047 2.360
H 690.4259 120 133.791 1.217
H 690.4274 120 137.160 1.905
H 690.4297 120 136.404 1.171
H 690.4309 120 135.153 0.992
H 690.4324 120 138.812 1.521
H 691.3710 120 131.955 1.019
H 691.3724 120 123.148 2.555
H 691.3739 120 133.668 2.891
H 691.3760 120 135.777 2.111
H 691.3774 120 150.531 4.325
H 691.3789 120 134.285 1.639
H 691.3812 120 133.176 2.647
H 691.3827 120 135.527 1.334
H 691.3842 120 132.809 2.524
H 691.3864 120 142.176 1.193
H 691.3878 120 137.033 1.349
H 691.3893 120 134.408 1.751
H 691.3913 120 140.355 5.166
H 691.3928 120 135.527 1.766
H 691.3943 120 141.914 1.849
H 691.3964 120 135.153 1.761
H 691.3977 120 136.781 0.972
H 691.3999 120 126.948 0.980
H 692.3336 120 119.022 2.366
H 692.3351 120 118.366 2.780
H 692.3366 120 118.803 2.361
H 692.3387 120 122.469 3.639
H 692.3402 120 128.952 2.681
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 19
H 692.3417 120 118.257 2.777
H 692.3439 120 120.455 2.343
H 692.3453 120 118.584 3.864
H 692.3468 120 118.803 2.311
H 692.3489 120 120.012 2.641
H 692.3503 120 121.011 3.349
H 692.3518 120 118.693 2.726
H 692.3539 120 116.634 3.385
H 692.3553 120 119.792 2.751
H 692.3569 120 119.681 2.690
H 692.3590 120 117.714 3.835
H 692.3605 120 119.241 2.370
H 692.3619 120 118.584 2.916
H 692.3717 120 124.631 2.448
H 692.3729 120 121.346 3.439
H 692.3743 120 118.912 2.517
H 692.3759 120 119.131 2.400
H 692.3778 120 119.681 2.943
H 692.3793 120 119.681 3.392
H 692.3807 120 117.065 2.327
H 692.3828 120 120.566 2.507
H 692.3843 120 117.714 2.371
H 692.3857 120 119.022 2.366
H 692.3878 120 117.822 2.315
H 692.3907 120 120.234 2.459
H 692.3922 120 120.677 2.348
H 692.3937 120 120.900 2.839
H 692.3959 120 118.257 3.352
H 692.3973 120 121.235 2.847
H 692.3988 120 120.789 2.433
H 692.4003 120 122.582 2.595
H 692.4017 120 121.458 2.525
H 692.4032 120 119.131 2.340
H 692.4053 120 122.582 2.385
H 692.4067 120 120.900 2.403
H 692.4082 120 119.681 2.811
H 692.4103 120 122.356 2.432
H 692.4118 120 119.461 3.467
H 692.4133 120 121.235 2.668
H 692.4155 120 121.346 2.384
H 692.4169 120 123.716 2.407
H 692.4184 120 118.148 2.298
H 692.4500 120 118.803 2.790
H 692.4514 120 123.148 2.419
H 692.4551 120 120.789 2.715
H 692.4565 120 119.461 2.374
H 692.4580 120 116.527 2.423
H 692.4602 120 122.469 2.876
H 692.4616 120 121.011 2.377
H 693.3339 120 124.631 1.014
H 693.3353 120 124.516 1.364
H 693.3368 120 123.261 1.618
H 693.3389 120 123.602 1.440
H 693.3403 120 124.516 1.451
H 693.3417 120 121.794 1.692
H 693.3438 120 121.011 1.410
H 693.3453 120 120.123 1.093
H 693.3467 120 121.570 0.989
20 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 693.3489 120 124.173 1.130
H 693.3503 120 122.695 1.117
H 693.3519 120 121.123 1.102
H 693.3541 120 119.351 1.025
H 693.3556 120 122.131 1.111
H 693.3571 120 123.261 1.122
H 693.3593 120 121.458 1.503
H 693.3607 120 129.189 2.209
H 693.3622 120 122.695 1.263
H 693.3643 120 123.488 1.195
H 693.3658 120 122.244 1.112
H 693.3673 120 120.455 1.096
H 693.3694 120 122.131 1.792
H 693.3708 120 120.234 1.032
H 693.3723 120 122.131 0.994
H 693.3745 120 123.261 1.712
H 693.3760 120 121.570 1.176
H 693.3774 120 121.682 1.882
H 693.3795 120 121.906 1.984
H 693.3798 120 123.261 4.246
H 693.3813 120 121.458 2.901
H 693.3834 120 125.091 1.288
H 693.3849 120 120.566 1.035
H 693.3878 120 124.516 1.133
H 693.3892 120 125.784 2.151
H 693.3907 120 122.808 1.520
H 693.3927 120 125.322 1.373
H 693.3942 120 124.861 1.368
H 693.3959 120 125.206 1.139
H 693.3977 120 126.831 2.486
H 693.3992 120 126.132 1.220
H 693.4006 120 130.625 3.120
H 693.4022 120 127.182 3.482
H 693.4037 120 125.669 2.463
H 693.4052 120 124.746 1.071
H 693.4073 120 124.287 2.861
H 693.4088 120 125.553 1.143
H 693.4091 120 125.669 4.777
H 693.4126 120 125.437 3.655
H 693.4141 120 126.598 3.466
H 693.4155 120 127.652 1.873
H 693.4176 120 124.631 1.636
H 693.4191 120 126.016 1.654
H 693.4205 120 124.631 1.928
H 693.4226 120 125.322 2.040
H 693.4241 120 124.746 2.340
H 693.4256 120 125.322 4.429
H 693.4276 120 126.248 5.251
H 693.4291 120 128.714 4.663
H 693.4305 120 128.359 6.955
H 693.4327 120 127.887 7.968
H 693.4342 120 129.070 2.860
H 693.4357 120 132.077 6.561
H 693.4377 120 126.016 6.373
H 693.4392 120 129.786 6.214
H 693.4407 120 126.948 7.566
H 693.4421 120 126.714 6.067
H 693.4436 120 130.986 8.754
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 21
H 693.4451 120 129.427 5.964
H 693.4471 120 124.746 9.127
H 693.4487 120 122.582 1.115
H 693.4501 120 124.287 1.067
H 693.4522 120 121.458 1.782
H 693.4537 120 120.455 1.165
H 693.4551 120 123.148 1.616
H 694.3585 120 126.598 1.567
H 694.3599 120 130.866 1.659
H 694.3615 120 125.784 1.557
H 694.3604 120 123.944 1.921
H 694.3649 120 126.248 1.563
H 694.3665 120 127.299 1.900
H 694.3685 120 123.944 1.921
H 694.3700 120 128.714 1.677
H 694.3715 120 128.241 1.587
H 694.3735 120 127.417 1.902
H 694.3750 120 129.666 5.188
H 694.3765 120 128.241 1.845
H 694.3785 120 129.905 2.530
H 694.3800 120 130.505 2.183
H 694.3815 120 129.382 1.639
H 694.3834 120 130.025 3.869
H 694.3849 120 129.308 4.726
H 694.3864 120 129.905 3.331
H 694.3884 120 129.308 3.316
H 694.3899 120 128.477 2.888
H 694.3913 120 127.769 1.581
H 694.3934 120 127.534 1.579
H 694.3948 120 130.625 3.140
H 694.3964 120 130.145 2.925
H 694.3983 120 130.265 1.697
H 694.3998 120 130.025 2.439
H 694.4013 120 130.986 1.707
H 694.4034 120 129.308 4.726
H 694.4049 120 131.349 2.654
H 694.4064 120 131.228 1.663
H 694.4078 120 131.955 2.764
H 694.4093 120 130.866 1.659
H 694.4108 120 126.714 1.606
H 694.4129 120 131.470 2.286
H 694.4144 120 128.833 1.633
H 694.4159 120 128.714 1.677
H 694.4175 120 131.228 2.113
H 694.4189 120 130.625 1.656
H 694.4204 120 132.809 1.683
H 694.4219 120 131.834 1.671
H 694.4233 120 132.931 1.984
H 694.4248 120 136.781 1.734
H 694.4270 120 136.153 2.554
H 694.4291 120 138.174 4.931
H 694.4307 120 133.914 3.762
H 694.4321 120 131.349 1.626
H 694.4341 120 134.532 1.705
H 694.4355 120 130.745 2.187
H 694.4370 120 132.564 1.727
H 694.4385 120 132.320 2.130
H 694.4399 120 132.564 2.878
22 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 694.4414 120 130.625 1.879
H 694.4435 120 130.265 1.809
H 694.4450 120 132.931 1.685
H 694.4465 120 132.564 3.083
H 694.4479 120 132.320 3.393
H 694.4495 120 133.176 2.498
H 694.4509 120 137.286 1.789
H 694.4529 120 133.299 1.650
H 694.4544 120 137.920 2.686
H 694.4559 120 135.527 4.146
H 695.3516 120 126.481 0.737
H 695.3531 120 128.241 1.476
H 695.3546 120 128.005 0.939
H 695.3566 120 126.365 1.029
H 695.3580 120 126.481 0.737
H 695.3596 120 124.631 0.642
H 695.3616 120 124.631 2.313
H 695.3630 120 126.132 0.735
H 695.3645 120 127.887 1.694
H 695.3667 120 129.786 0.952
H 695.3682 120 125.553 0.824
H 695.3696 120 126.714 0.738
H 695.3711 120 124.746 0.819
H 695.3726 120 128.952 1.156
H 695.3740 120 130.265 1.277
H 695.3765 120 129.427 0.754
H 695.3779 120 126.714 1.242
H 695.3794 120 129.666 1.493
H 695.3815 120 124.631 0.642
H 695.3829 120 124.402 1.115
H 695.3844 120 125.669 1.775
H 695.3857 120 125.437 1.229
H 695.3879 120 132.564 1.990
H 695.3894 120 128.359 0.842
H 695.3915 120 128.596 1.817
H 695.3929 120 126.481 0.737
H 695.3944 120 123.602 0.811
H 695.3965 120 125.322 0.645
H 695.3979 120 129.189 1.939
H 695.3994 120 130.745 0.673
H 695.4015 120 124.746 0.915
H 695.4030 120 128.596 1.260
H 695.4044 120 128.005 1.696
H 695.4065 120 123.716 0.637
H 695.4080 120 129.905 1.835
H 695.4095 120 126.365 0.927
H 696.3481 120 129.070 1.375
H 696.3496 120 126.016 1.437
H 695.1936 120 129.547 1.477
H 696.3533 120 129.189 1.748
H 696.3547 120 131.955 1.505
H 696.3562 120 132.442 1.510
H 696.3583 120 128.833 1.417
H 696.3597 120 130.625 1.436
H 696.3612 120 132.564 1.877
H 696.3633 120 131.470 1.861
H 696.3647 120 133.791 1.587
H 696.3662 120 129.308 1.831
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 23
H 696.3677 120 128.596 1.820
H 696.3698 120 126.598 1.444
H 696.3713 120 127.652 1.404
H 696.3727 120 128.714 1.665
H 696.3749 120 131.470 1.499
H 696.3763 120 128.477 1.738
H 696.3778 120 130.745 1.438
H 696.3815 120 130.986 2.217
H 696.3829 120 130.745 1.691
H 696.3844 120 131.228 2.319
H 696.3865 120 129.905 2.013
H 696.3879 120 133.054 2.351
H 696.3894 120 130.986 1.554
H 696.3915 120 130.505 1.765
H 696.3930 120 130.265 1.612
H 696.3945 120 134.038 1.897
H 696.3966 120 132.199 2.142
H 696.3981 120 132.564 1.641
H 696.3995 120 131.107 1.556
H 696.4016 120 130.986 2.030
H 696.4031 120 130.986 3.365
H 696.4053 120 131.712 7.665
H 696.4073 120 131.712 1.502
H 696.4088 120 131.107 2.935
H 699.3295 120 124.976 1.120
H 699.3309 120 127.887 1.259
H 699.3325 120 124.402 1.225
H 699.3345 120 124.058 1.785
H 699.3360 120 121.011 1.256
H 699.3375 120 122.356 1.761
H 699.3396 120 123.716 1.159
H 699.3411 120 125.437 1.175
H 699.3426 120 123.944 2.071
H 699.3454 120 123.944 3.210
H 699.3469 120 123.944 1.358
H 699.3484 120 123.944 1.161
H 699.3505 120 120.123 2.904
H 699.3521 120 123.716 1.433
H 699.3535 120 123.148 1.426
H 699.3555 120 122.131 1.850
H 699.3569 120 122.244 1.145
H 699.3584 120 123.944 2.474
H 699.3605 120 124.631 3.879
H 699.3619 120 125.091 1.707
H 699.3634 120 125.437 1.536
H 699.3654 120 122.921 1.862
H 699.3669 120 123.148 2.872
H 699.3683 120 121.458 1.089
H 699.4052 120 126.831 1.137
H 699.3718 120 121.123 1.192
H 699.3734 120 123.602 1.217
H 699.3754 120 127.299 1.474
H 699.3768 120 127.652 2.654
H 699.3784 120 130.265 1.282
H 699.3821 120 126.481 1.465
H 699.3835 120 128.833 1.207
H 699.3850 120 126.948 3.288
H 699.3871 120 126.831 1.248
24 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 699.3885 120 129.666 3.247
H 699.3900 120 130.866 3.389
H 699.3922 120 126.831 3.176
H 699.3936 120 125.437 1.997
H 699.3950 120 125.091 1.371
H 699.3971 120 123.716 1.356
H 699.3986 120 122.356 1.146
H 699.4000 120 123.830 1.110
H 699.4023 120 126.948 1.250
H 699.4038 120 122.469 1.147
H 699.4052 120 124.402 1.225
H 699.4073 120 126.481 5.734
H 699.4088 120 124.287 1.978
H 699.4103 120 125.322 1.534
H 699.4123 120 124.402 1.441
H 699.4138 120 122.921 1.769
H 699.4153 120 125.784 1.378
H 699.4173 120 125.437 2.196
H 699.4188 120 124.516 1.524
H 699.4202 120 123.034 1.425
H 699.4224 120 123.944 1.220
H 699.4238 120 122.808 1.274
H 699.4253 120 121.906 1.492
H 700.3828 120 124.059 1.010
H 700.3843 120 123.944 1.128
H 700.3857 120 125.553 1.215
H 700.3879 120 124.402 1.068
H 700.3893 120 122.131 1.111
H 700.3908 120 129.427 1.053
H 700.3929 120 126.715 1.088
H 700.3943 120 126.831 1.306
H 700.3958 120 122.356 1.113
H 700.3978 120 127.534 1.579
H 700.3994 120 127.065 1.156
H 700.4009 120 125.206 1.643
H 700.4030 120 125.553 1.376
H 700.4044 120 128.952 1.413
H 700.4059 120 124.516 1.926
H 700.4079 120 125.669 1.144
H 700.4091 120 126.365 1.385
H 700.4108 120 125.553 1.078
H 700.4129 120 126.249 1.221
H 700.4143 120 125.206 1.019
H 700.4158 120 124.976 1.287
H 700.4178 120 124.631 1.206
H 700.4193 120 126.365 2.371
H 700.4208 120 124.402 1.633
H 700.4244 120 127.652 1.096
H 700.4259 120 127.065 1.392
H 700.4274 120 126.132 1.027
H 700.4288 120 126.249 1.149
H 700.4291 120 125.206 2.141
H 700.4305 120 130.745 2.344
H 700.4326 120 127.417 3.488
H 700.4341 120 126.831 2.273
H 700.4355 120 123.944 1.627
H 700.4376 120 124.861 3.200
H 700.4391 120 124.516 1.827
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 25
H 700.4406 120 127.887 1.401
H 700.4420 120 126.715 1.859
H 700.4435 120 123.602 1.530
H 700.4449 120 127.769 1.489
H 700.4464 120 124.173 1.130
H 700.4479 120 123.602 1.354
H 700.4499 120 122.695 1.430
H 700.4514 120 123.375 1.059
H 700.4529 120 125.553 1.744
H 700.4549 120 124.516 1.069
H 700.4448 120 123.830 1.357
H 700.4463 120 123.375 1.352
H 700.4598 120 123.716 1.062
H 700.4614 120 126.948 1.228
H 700.4628 120 120.012 1.236
H 700.4642 120 122.469 1.261
H 701.3506 120 117.281 1.487
H 701.3521 120 117.389 1.752
H 701.3535 120 120.012 1.521
H 701.3558 120 122.244 2.293
H 701.3572 120 117.497 1.632
H 701.3588 120 116.312 1.674
H 701.3608 120 117.605 1.692
H 701.3622 120 118.912 1.652
H 701.3637 120 116.098 1.733
H 701.3658 120 113.143 1.434
H 701.3672 120 113.770 1.978
H 701.3688 120 114.611 1.917
H 701.3708 120 113.247 1.823
H 701.3724 120 112.209 1.422
H 701.3738 120 110.364 1.777
H 701.3759 120 112.002 1.874
H 701.3774 120 116.420 1.476
H 701.3789 120 115.671 1.664
H 701.3810 120 116.205 1.734
H 701.3824 120 117.065 1.747
H 701.3839 120 119.131 1.601
H 701.3862 120 118.475 1.768
H 701.3876 120 115.671 1.664
H 701.3890 120 111.078 1.931
H 701.3911 120 116.527 1.677
H 701.3926 120 117.281 1.687
H 701.3940 120 115.778 1.728
H 701.3962 120 115.671 1.507
H 701.3977 120 118.803 2.065
H 701.3996 120 117.931 1.697
H 701.4011 120 117.281 1.687
H 701.4026 120 118.693 1.546
H 701.4045 120 119.131 1.714
H 701.4060 120 117.497 1.579
H 701.4075 120 119.351 1.555
H 701.4095 120 118.693 1.772
H 701.4110 120 119.131 1.714
H 701.4125 120 116.742 1.445
H 701.4147 120 115.991 1.511
H 701.4162 120 116.957 2.033
H 701.4177 120 116.742 1.809
H 701.4199 120 116.420 1.517
26 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 701.4214 120 117.713 1.694
H 701.4229 120 114.189 1.447
H 702.3953 120 124.173 1.680
H 702.3967 120 123.602 1.814
H 702.3982 120 123.716 2.229
H 702.4003 120 125.784 1.743
H 702.4017 120 125.437 1.739
H 702.4032 120 121.235 1.640
H 702.4053 120 125.091 1.782
H 702.4067 120 124.746 2.679
H 702.4082 120 123.602 1.814
H 702.4103 120 122.695 1.701
H 702.4117 120 125.900 1.703
H 702.4132 120 125.437 2.181
H 702.4152 120 124.631 1.651
H 702.4174 120 122.356 1.621
H 702.4194 120 124.059 2.157
H 702.4214 120 122.582 1.799
H 702.4224 120 124.631 1.686
H 702.4244 120 124.976 1.732
H 702.4259 120 122.244 2.051
H 702.4274 120 125.437 1.662
H 702.4294 120 125.437 1.900
H 702.4309 120 123.148 1.928
H 702.4324 120 124.402 2.087
H 702.4344 120 123.716 1.674
H 702.4359 120 125.206 1.735
H 702.4374 120 124.631 1.888
H 702.4393 120 124.631 1.727
H 702.4408 120 123.944 1.819
H 702.4423 120 123.830 1.875
H 702.4443 120 123.375 1.669
H 702.4458 120 124.861 2.095
H 702.4473 120 123.148 2.066
H 702.4493 120 126.249 1.750
H 702.4508 120 123.602 1.672
H 702.4523 120 124.173 1.680
H 702.4537 120 122.808 1.802
H 703.4019 120 116.957 1.096
H 703.4033 120 114.295 1.478
H 703.4048 120 115.885 1.086
H 703.4062 120 113.979 1.068
H 703.4077 120 113.770 1.066
H 703.4092 120 118.039 1.106
H 703.4113 120 115.671 1.200
H 703.4128 120 112.727 1.056
H 703.4142 120 113.979 1.068
H 703.4163 120 112.416 1.166
H 703.4177 120 116.849 1.681
H 703.4192 120 118.257 1.448
H 703.4213 120 115.034 1.078
H 703.4228 120 112.209 1.104
H 703.4242 120 116.098 1.205
H 703.4263 120 117.497 1.288
H 703.4277 120 115.034 1.078
H 703.4298 120 116.312 1.145
H 703.4313 120 116.312 1.090
H 703.4340 120 113.874 1.067
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 27
H 703.4354 120 118.475 1.450
H 703.4370 120 115.992 2.706
H 703.4390 120 115.459 1.136
H 703.4405 120 118.257 1.370
H 703.4420 120 112.727 1.056
H 668.7222 120 114.190 1.070
H 703.4456 120 114.928 1.077
H 703.4470 120 116.527 1.427
H 703.4485 120 114.084 1.184
H 703.5240 120 114.822 1.852
H 703.5255 120 118.475 2.026
H 703.5270 120 116.205 2.329
H 703.5284 120 116.098 1.872
H 703.5300 120 117.173 2.051
H 703.5314 120 115.459 2.072
H 703.5334 120 118.475 1.910
H 703.5349 120 116.420 2.205
H 703.5364 120 115.459 1.862
H 703.5385 120 116.205 1.874
H 703.5399 120 115.991 1.870
H 703.5414 120 117.713 2.501
H 703.5428 120 114.611 1.960
H 703.5443 120 115.885 1.901
H 703.5458 120 118.366 2.072
H 703.5479 120 116.098 1.942
H 703.5493 120 114.822 2.010
H 703.5508 120 116.742 2.789
H 703.5529 120 116.849 1.884
H 703.5543 120 117.713 1.898
H 703.5558 120 118.584 1.984
H 703.5583 120 114.084 1.951
H 703.5598 120 116.849 2.097
H 703.5613 120 115.778 2.192
H 703.5634 120 113.979 2.158
H 703.5648 120 117.389 2.223
H 703.5663 120 117.605 2.167
H 703.5684 120 116.634 2.628
H 703.5698 120 116.312 1.989
H 703.5713 120 117.281 1.891
H 709.5557 120 114.505 2.709
H 709.5571 120 113.665 2.793
H 710.5570 120 118.148 0.925
H 710.5585 120 118.912 1.503
H 710.5613 120 118.366 1.315
H 710.5627 120 119.241 1.000
H 710.5643 120 118.039 1.876
H 710.5663 120 116.742 2.758
H 710.5673 120 117.930 1.973
H 710.5693 120 118.693 0.929
H 720.5547 120 118.584 2.774
H 720.5562 120 116.312 3.596
H 720.5577 120 120.344 3.037
H 720.5592 120 119.791 2.861
H 720.5607 120 123.716 3.172
H 720.5621 120 121.458 2.842
H 720.5636 120 121.794 4.078
H 720.5651 120 115.459 3.119
H 720.5666 120 119.791 3.423
28 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 721.5507 120 131.955 3.061
H 721.5521 120 125.206 3.027
H 721.5535 120 125.322 3.448
H 721.5557 120 131.591 3.109
H 721.5571 120 132.442 3.342
H 721.5585 120 130.385 3.655
H 721.5607 120 127.299 3.041
H 721.5621 120 128.005 2.970
H 721.5636 120 129.547 3.132
H 722.5481 120 123.261 8.973
H 722.5496 120 117.605 11.772
H 722.5510 120 127.065 9.366
J 633.4851 120 60.078 5.054
J 633.4935 120 59.637 5.078
J 633.5005 120 57.374 4.908
J 633.5074 120 61.026 5.165
J 633.5208 120 59.637 5.047
J 635.5070 120 57.163 1.229
J 635.6336 120 56.483 1.373
J 635.6411 120 56.691 0.912
J 635.6470 120 58.495 1.927
J 635.6531 120 56.223 0.904
J 635.6575 120 58.065 1.328
J 635.6643 120 56.743 1.339
J 635.6752 120 57.163 1.519
J 639.6642 120 55.657 1.692
J 639.6657 120 55.172 1.728
I 504.27 60 23.344 0.637
I 504.27 60 22.294 0.406
I 504.27 60 23.130 0.210
I 508.27 60 21.095 0.384
I 508.27 60 21.487 0.391
I 508.28 60 21.487 0.391
I 509.29 60 19.239 0.175
I 509.29 60 19.063 0.173
I 509.29 60 19.063 0.173
I 511.25 60 20.332 0.185
I 511.26 60 20.332 0.185
I 511.26 60 20.710 0.188
I 511.28 60 20.520 0.187
I 511.28 60 20.332 0.185
I 511.28 60 20.520 0.187
I 516.25 60 23.560 0.214
I 516.25 60 23.344 0.212
I 516.25 60 23.344 0.425
I 516.25 60 23.778 0.216
I 516.25 60 23.998 0.437
I 516.31 60 21.095 0.384
I 516.31 60 20.902 0.380
I 516.31 60 20.710 0.377
I 517.24 60 21.290 0.194
I 517.24 60 21.095 0.192
I 517.24 60 21.095 0.192
I 619.21 30 23.344 0.425
I 619.21 30 23.130 0.421
I 619.21 30 23.344 0.425
I 619.21 30 23.344 0.425
I 619.22 30 23.778 0.433
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 29
I 619.22 30 23.344 0.425
I 619.22 30 23.560 0.429
I 619.22 30 23.344 0.425
I 619.23 30 25.362 0.231
I 619.23 30 25.362 0.231
I 619.24 30 25.362 0.231
I 619.24 30 25.362 0.231
I 619.24 30 25.129 0.229
I 619.24 30 25.362 0.231
I 619.25 30 25.129 0.229
I 619.25 30 25.362 0.231
I 619.25 30 25.362 0.231
I 619.26 30 25.362 0.231
I 631.13 30 24.220 0.441
I 631.13 30 23.778 0.433
I 631.13 30 23.998 0.437
I 631.13 30 25.362 0.462
I 632.98 30 30.774 0.280
I 632.98 30 30.774 0.280
I 632.99 30 31.346 0.285
I 632.99 30 31.929 0.291
I 632.99 30 33.127 1.206
I 632.99 30 33.434 0.304
I 633 30 30.492 0.555
I 633 30 30.492 0.555
I 633 30 29.661 0.540
I 633 30 29.661 0.540
I 633.01 30 28.852 0.263
I 633.01 30 28.852 0.525
I 633.01 30 28.066 0.255
I 633.01 30 28.066 0.511
I 633.02 30 27.554 0.501
I 633.02 30 27.051 0.492
I 633.03 30 27.554 0.501
I 633.03 30 27.301 0.248
I 634.98 30 26.314 0.479
I 634.99 30 25.362 0.462
I 634.99 30 25.129 0.457
I 634.99 30 25.129 0.457
I 635.1 30 31.929 0.581
I 635.1 30 33.743 0.614
I 635.12 30 25.597 0.932
I 635.12 30 25.833 0.940
I 635.13 30 25.597 0.699
I 635.13 30 26.314 0.718
I 635.14 30 28.326 0.516
I 635.15 30 28.066 0.511
I 635.15 30 28.326 0.516
I 635.16 30 28.588 0.520
I 635.16 30 29.119 0.530
I 635.17 30 29.119 0.795
I 635.17 30 28.852 0.525
I 635.17 30 28.852 0.525
I 635.17 30 28.066 0.511
I 635.18 30 29.119 0.795
I 635.18 30 29.389 0.535
I 635.18 30 29.119 0.530
I 635.19 30 28.852 2.100
30 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
I 640.22 120 29.119 0.265
I 640.22 120 29.119 0.265
I 641.11 120 29.389 0.535
I 641.11 120 28.852 0.525
I 643.21 120 30.774 0.280
I 643.22 120 30.774 0.280
I 644.1 120 31.346 0.285
I 644.1 120 31.346 0.285
I 648.2 120 32.224 0.586
I 648.21 120 32.522 0.592
I 648.22 120 32.224 0.586
I 655.03 120 32.224 1.759
I 655.03 120 32.224 0.586
I 655.2 120 31.929 0.581
I 655.03 120 28.066 0.255
I 655.03 120 27.809 0.253
I 655.2 120 34.370 0.313
I 655.2 120 34.370 0.313
I 655.21 120 35.009 0.319
I 655.21 120 35.009 0.319
I 655.22 120 34.688 0.316
I 655.22 120 35.009 0.319
I 678.03 120 39.827 0.626
I 678.03 120 39.608 0.639
I 678.04 120 39.974 0.645
I 678.04 120 39.718 0.713
I 678.06 120 38.885 0.618
I 678.06 120 39.608 0.794
I 678.07 120 39.173 0.615
I 678.07 120 39.901 0.655
I 678.09 120 39.245 0.657
I 678.09 120 39.245 0.624
I 678.1 120 39.644 0.639
I 678.12 120 38.387 0.610
I 678.12 120 38.529 0.612
I 678.13 120 38.422 0.630
I 678.13 120 38.493 0.612
I 679.08 120 37.756 1.039
I 679.09 120 38.778 0.848
I 680.01 120 39.974 0.635
I 680.02 120 38.000 0.665
I 680.03 120 37.410 0.671
I 680.03 120 37.375 0.639
I 680.04 120 36.896 0.595
I 680.05 120 37.617 0.629
I 680.06 120 37.169 0.599
I 680.06 120 38.035 0.613
I 680.08 120 37.410 0.655
I 680.08 120 37.272 0.815
I 680.14 120 35.726 0.568
I 680.14 120 35.924 0.564
I 681.1 120 38.458 0.643
I 681.1 120 38.210 0.607
I 681.11 120 38.529 0.612
I 681.12 120 36.457 0.579
I 681.13 120 39.245 0.937
I 681.13 120 39.901 0.716
I 682.03 120 38.000 0.604
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 31
I 682.03 120 37.860 0.602
I 682.04 120 37.169 0.591
I 682.05 120 36.896 0.586
I 682.06 120 36.491 0.580
I 682.06 120 36.357 0.596
I 682.07 120 36.457 0.672
I 682.08 120 36.794 0.616
I 682.1 120 36.457 0.731
I 682.1 120 36.189 0.605
I 682.11 120 36.223 0.747
I 682.11 120 36.693 0.851
I 682.13 120 35.660 0.610
I 682.13 120 36.090 0.767
I 683.02 120 38.210 0.788
I 683.02 120 37.169 0.599
I 683.02 120 36.223 0.584
I 683.03 120 36.457 0.588
I 683.03 120 35.594 0.574
I 683.05 120 35.431 0.593
I 683.05 120 35.792 0.577
I 683.06 120 35.924 0.579
I 683.06 120 38.849 0.680
I 684.02 120 38.885 0.802
I 684.02 120 39.390 0.626
I 684.04 120 39.608 0.771
I 684.04 120 38.529 0.605
I 684.05 120 37.479 0.604
I 684.05 120 39.101 0.631
I 684.07 120 39.029 0.719
I 684.07 120 36.189 0.633
I 689.02 120 36.761 0.603
I 689.02 120 36.896 0.662
I 689.03 120 35.957 0.645
I 689.04 120 41.132 0.663
I 690.08 120 40.718 0.647
I 690.08 120 42.285 0.759
I 690.09 120 42.052 0.704
I 690.11 120 42.480 0.851
I 690.11 120 41.589 0.696
I 690.11 120 42.794 1.022
I 691.06 120 41.704 0.655
I 691.06 120 42.013 0.718
I 691.08 120 42.207 0.951
I 691.08 120 38.387 0.619
I 692.02 120 38.105 0.684
I 692.02 120 39.426 0.660
I 692.04 120 39.101 0.669
I 692.04 120 37.825 0.601
I 692.06 120 38.210 0.639
I 692.08 120 38.778 0.616
I 692.08 120 38.885 0.611
I 692.14 120 39.827 0.734
I 693.02 120 39.608 0.629
I 693.03 120 39.499 0.709
I 693.04 120 38.849 0.680
I 693.04 120 38.458 0.643
I 693.05 120 38.316 0.609
I 693.06 120 39.426 0.747
32 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
I 693.07 120 39.029 0.700
I 693.08 120 38.635 0.634
I 693.09 120 37.548 0.775
I 693.09 120 37.965 0.603
I 693.1 120 37.686 0.592
I 693.11 120 37.756 0.600
I 693.12 120 37.930 0.596
I 693.12 120 38.387 0.610
I 693.14 120 37.513 0.596
I 694.05 120 38.210 0.600
I 694.05 120 38.493 0.612
I 694.08 120 38.493 0.612
I 694.08 120 39.462 0.627
I 694.09 120 39.974 0.635
I 694.1 120 40.011 0.636
I 694.11 120 39.499 0.769
I 694.11 120 40.868 0.649
I 694.11 120 40.568 0.679
I 694.13 120 39.499 0.675
I 694.13 120 39.390 0.689
I 694.14 120 39.353 0.635
I 694.14 120 39.101 0.614
I 695.05 120 40.680 0.639
I 695.05 120 39.938 0.635
I 695.06 120 38.921 0.628
I 695.07 120 38.671 1.275
I 695.08 120 38.635 0.614
I 695.08 120 38.458 0.611
I 695.09 120 39.137 0.685
I 695.1 120 38.422 0.604
I 696.05 120 39.101 0.621
I 696.05 120 39.245 0.704
I 696.06 120 40.531 0.693
I 696.06 120 40.196 0.639
I 696.08 120 40.643 0.646
I 696.08 120 40.755 0.794
I 696.09 120 40.943 0.660
I 699.03 120 41.475 0.785
I 699.03 120 41.436 0.651
I 699.04 120 40.906 0.650
I 699.04 120 41.436 0.693
I 699.04 120 41.551 0.787
I 699.06 120 42.052 0.796
I 699.06 120 41.132 0.675
I 699.08 120 41.360 0.667
I 699.08 120 41.666 0.729
I 699.09 120 40.755 0.648
I 699.1 120 41.589 0.653
I 699.11 120 40.943 0.651
I 699.11 120 41.936 0.666
I 700.04 120 41.284 0.723
I 700.04 120 41.170 0.849
I 700.05 120 46.388 0.107
I 700.05 120 40.793 0.714
I 700.05 120 40.793 0.641
I 700.08 120 41.246 0.648
I 700.08 120 40.943 0.651
I 700.09 120 40.755 0.713
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 33
I 700.1 120 40.270 0.742
I 700.11 120 40.755 0.713
I 700.11 120 40.680 0.647
I 701.03 120 40.943 0.735
I 701.03 120 37.895 0.648
I 701.04 120 37.721 0.695
I 701.05 120 38.387 0.610
I 701.06 120 38.387 0.619
I 701.06 120 38.778 0.874
I 701.07 120 39.137 0.702
I 701.07 120 37.479 0.615
I 701.07 120 37.895 0.648
I 701.09 120 37.101 0.590
I 701.09 120 37.238 0.592
I 702.04 120 39.499 0.691
I 702.04 120 40.307 0.763
I 702.05 120 40.382 0.634
I 702.05 120 40.270 0.633
I 702.07 120 41.094 0.653
I 702.07 120 40.568 0.645
I 702.08 120 41.132 0.654
I 702.08 120 41.513 0.669
I 703.05 120 36.592 0.657
I 703.06 120 37.341 0.593
I 703.06 120 37.375 0.613
I 703.08 120 36.964 0.647
I 703.08 120 37.341 0.638
I 704.04 120 36.390 0.622
I 704.04 120 36.056 0.581
I 704.06 120 36.998 0.597
I 704.06 120 36.625 0.575
I 704.08 120 36.896 0.586
I 704.08 120 37.721 0.599
I 711.07 120 36.524 0.574
I 711.08 120 36.090 0.592
I 715.04 120 37.032 0.633
I 715.04 120 36.794 0.616
I 715.05 120 36.964 0.596
I 715.05 120 36.727 0.643
I 721.06 120 34.212 0.585
I 721.06 120 35.236 0.560
I 722.06 120 37.965 0.783
I 722.06 120 38.281 0.705
R 504.27 60 20.601 0.375
R 504.28 60 19.856 0.361
R 504.28 60 20.791 0.757
R 508.28 60 17.942 0.163
R 508.28 60 17.778 0.162
R 508.29 60 17.778 0.162
R 509.29 60 17.778 0.162
R 509.29 60 17.615 0.160
R 509.29 60 17.778 0.162
R 510.3 60 16.214 0.295
R 510.3 60 16.364 0.149
R 510.3 60 16.364 0.149
R 511.26 60 18.962 0.173
R 511.26 60 18.788 0.171
R 511.26 60 19.137 0.174
34 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
R 511.28 60 18.962 0.173
R 511.28 60 18.788 0.171
R 511.28 60 18.788 0.171
R 516.25 60 21.178 0.193
R 516.25 60 18.445 0.168
R 516.25 60 18.616 0.169
R 517.24 60 19.674 0.179
R 517.24 60 19.314 0.176
R 517.24 60 19.493 0.177
R 517.25 60 19.493 0.177
R 517.25 60 19.493 0.177
R 517.25 60 19.493 0.177
R 619.2 30 26.175 0.476
R 619.21 30 26.175 0.476
R 619.21 30 26.175 0.476
R 619.21 30 26.175 0.476
R 619.22 30 23.653 0.215
R 619.22 30 23.653 0.215
R 619.23 30 23.872 0.217
R 619.23 30 23.872 0.217
R 619.24 30 23.653 0.215
R 619.24 30 23.872 0.217
R 619.24 30 23.653 0.215
R 619.24 30 23.872 0.217
R 619.25 30 24.093 0.219
R 619.25 30 24.093 0.219
R 619.25 30 24.093 0.219
R 619.25 30 24.093 0.219
R 631.13 30 26.661 0.485
R 631.13 30 26.908 0.490
R 632.98 30 28.700 0.261
R 632.98 30 28.700 0.261
R 632.99 30 28.966 0.264
R 632.99 30 28.700 0.261
R 632.99 30 28.966 0.264
R 632.99 30 28.966 0.264
R 632.99 30 29.234 0.266
R 632.99 30 29.234 0.266
R 633 30 28.700 0.261
R 633 30 28.700 0.261
R 633.01 30 27.918 0.254
R 633.01 30 28.176 0.256
R 633.01 30 27.662 0.252
R 633.01 30 27.408 0.249
R 633.02 30 26.661 0.243
R 633.02 30 26.661 0.243
R 633.02 30 26.417 0.240
R 633.02 30 26.417 0.240
R 634.98 30 23.653 0.215
R 634.98 30 23.008 0.209
R 634.98 30 23.872 0.217
R 634.98 30 23.872 0.217
R 635.1 30 27.408 0.249
R 635.1 30 27.408 0.249
R 635.13 30 28.176 0.769
R 635.13 30 28.966 0.527
R 635.13 30 28.437 1.035
R 635.13 30 28.437 0.776
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 35
R 635.14 30 29.777 0.813
R 635.14 30 28.700 0.784
R 635.15 30 28.176 0.769
R 635.15 30 28.700 0.784
R 635.15 30 26.175 0.238
R 635.15 30 25.697 0.468
R 635.16 30 25.935 0.236
R 635.16 30 25.935 0.236
R 635.17 30 24.093 0.658
R 635.17 30 25.935 0.236
R 635.17 30 25.935 0.236
R 635.18 30 26.417 0.240
R 635.18 30 26.661 0.485
R 635.18 30 25.697 0.468
R 635.18 30 24.997 0.455
R 635.19 30 25.935 0.472
R 635.19 30 26.417 0.481
R 640.22 120 28.966 0.264
R 640.22 120 27.408 0.249
R 641.11 120 31.760 0.578
R 641.11 120 31.760 0.578
R 644.1 120 27.408 0.499
R 644.1 120 27.662 0.503
R 648.21 120 28.437 0.259
R 648.21 120 28.966 0.264
R 648.22 120 28.437 0.518
R 648.22 120 30.053 1.641
R 652.05 120 31.760 0.289
R 655.02 120 26.417 0.240
R 655.02 120 26.417 0.240
R 655.03 120 25.461 0.232
R 655.03 120 25.461 0.232
R 655.2 120 32.351 0.294
R 655.2 120 32.351 0.294
R 655.21 120 32.351 0.294
R 655.21 120 32.351 0.294
R 665.04 30 31.469 0.573
R 665.04 30 32.054 0.583
R 678.02 30 34.824 0.634
R 678.02 120 35.480 0.915
R 678.02 120 35.980 0.927
R 678.04 120 35.980 0.957
R 678.04 120 35.409 0.914
R 678.05 120 35.303 0.925
R 678.05 120 35.409 0.922
R 678.07 120 35.303 0.919
R 678.07 120 35.551 0.920
R 678.08 120 34.846 0.989
R 678.08 120 34.846 0.908
R 678.1 120 34.846 0.904
R 678.1 120 34.637 0.909
R 678.11 120 34.222 0.893
R 678.11 120 34.119 0.891
R 678.13 120 33.406 0.869
R 678.13 120 33.676 0.876
R 679.08 120 34.187 0.958
R 679.08 120 33.880 0.891
R 680.01 120 33.507 1.134
36 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
R 680.01 120 33.507 1.248
R 680.02 120 33.138 1.062
R 680.03 120 32.707 0.857
R 680.04 120 32.972 0.869
R 680.04 120 33.238 0.933
R 680.05 120 33.005 1.185
R 680.06 120 33.005 0.970
R 680.07 120 32.707 1.318
R 680.07 120 32.905 1.159
R 680.13 120 32.707 0.896
R 680.13 120 31.731 0.862
R 681.09 120 31.699 0.845
R 681.1 120 34.360 0.892
R 681.11 120 34.498 0.900
R 681.11 120 34.291 0.960
R 681.12 120 34.429 0.929
R 681.13 120 34.671 0.917
R 682.02 120 35.021 0.934
R 682.03 120 34.846 0.939
R 682.04 120 34.846 1.176
R 682.04 120 33.744 1.023
R 682.05 120 33.272 1.046
R 682.06 120 32.806 1.156
R 682.07 120 32.905 0.874
R 682.07 120 33.812 0.889
R 682.09 120 33.744 1.120
R 682.09 120 31.539 0.997
R 682.11 120 31.476 0.847
R 682.11 120 32.021 0.890
R 682.12 120 31.317 0.862
R 682.12 120 31.190 0.832
R 683.01 120 31.444 0.832
R 683.01 120 31.190 0.858
R 683.03 120 31.635 0.831
R 683.03 120 31.476 0.828
R 683.04 120 31.731 0.853
R 683.04 120 32.086 0.842
R 683.06 120 31.731 0.834
R 683.06 120 30.782 0.816
R 684.01 120 31.001 0.821
R 684.01 120 33.339 0.936
R 684.02 120 33.305 0.884
R 684.02 120 34.085 0.896
R 684.03 120 33.541 0.877
R 684.03 120 34.050 0.919
R 684.05 120 34.602 0.997
R 684.05 120 34.256 0.915
R 684.06 120 34.050 0.919
R 684.06 120 33.812 0.879
R 689.01 120 33.744 0.882
R 689.02 120 31.892 0.837
R 689.03 120 32.183 0.844
R 689.03 120 32.054 0.870
R 690.07 120 32.444 0.851
R 690.08 120 36.161 0.953
R 690.09 120 35.056 0.935
R 690.09 120 35.909 0.934
R 690.1 120 36.125 0.934
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 37
R 690.11 120 36.269 0.998
R 691.06 120 36.415 0.946
R 691.06 120 36.891 1.216
R 691.07 120 38.277 1.190
R 691.07 120 37.410 1.027
R 692.02 120 37.112 1.137
R 692.02 120 33.914 0.886
R 692.03 120 34.256 0.915
R 692.03 120 33.272 0.883
R 692.05 120 33.406 1.032
R 692.06 120 33.138 0.867
R 692.07 120 33.272 0.871
R 692.08 120 33.071 0.866
R 692.09 120 33.948 0.887
R 692.09 120 33.575 0.878
R 692.13 120 33.507 0.916
R 692.13 120 33.914 0.927
R 693.02 120 34.567 0.902
R 693.02 120 34.222 0.893
R 693.03 120 33.710 0.881
R 693.04 120 33.238 0.870
R 693.05 120 33.812 0.883
R 693.05 120 33.642 0.879
R 693.06 120 33.105 0.867
R 693.07 120 33.205 0.869
R 693.07 120 33.205 0.869
R 693.07 120 32.905 0.862
R 693.08 120 33.005 0.864
R 693.09 120 32.608 0.855
R 693.1 120 32.938 0.863
R 693.1 120 32.872 0.861
R 693.11 120 32.839 0.860
R 693.12 120 32.740 0.858
R 694.05 120 35.729 0.929
R 694.05 120 35.409 0.922
R 694.06 120 35.587 0.926
R 694.06 120 35.622 0.927
R 694.07 120 34.916 0.910
R 694.07 120 34.811 0.907
R 694.09 120 35.232 0.917
R 694.09 120 35.551 0.931
R 694.1 120 35.515 0.924
R 695.04 120 34.637 0.903
R 695.05 120 34.741 0.906
R 695.06 120 33.880 0.881
R 695.06 120 34.085 0.890
R 695.07 120 33.744 0.888
R 695.08 120 33.778 0.883
R 695.09 120 34.187 0.892
R 695.09 120 33.914 0.886
R 696.04 120 35.338 0.974
R 696.04 120 34.986 0.907
R 696.06 120 34.532 0.901
R 696.06 120 34.567 0.902
R 696.07 120 35.056 0.913
R 696.08 120 35.126 0.915
R 696.09 120 36.016 0.931
R 696.09 120 36.089 1.021
38 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
R 699.02 120 37.186 1.180
R 699.02 120 36.927 1.217
R 699.04 120 35.444 1.217
R 699.04 120 36.744 1.146
R 699.05 120 36.089 0.933
R 699.05 120 36.488 0.991
R 699.07 120 35.837 0.932
R 699.08 120 35.658 0.923
R 699.09 120 36.233 0.941
R 699.09 120 35.622 1.040
R 699.1 120 36.089 0.933
R 699.11 120 36.415 0.989
R 700.03 120 36.161 0.940
R 700.03 120 35.837 0.932
R 700.05 120 35.409 0.922
R 700.05 120 35.480 0.923
R 700.06 120 35.338 0.920
R 700.06 120 35.303 0.919
R 700.07 120 34.846 0.908
R 700.08 120 35.021 0.912
R 700.09 120 34.222 0.893
R 700.09 120 35.091 0.914
R 700.1 120 35.056 0.909
R 700.11 120 35.303 0.919
R 701.02 120 33.440 0.875
R 701.03 120 33.473 0.871
R 701.04 120 34.085 0.890
R 701.04 120 34.016 0.997
R 701.05 120 33.676 0.932
R 701.06 120 33.812 1.008
R 701.07 120 33.778 1.024
R 701.07 120 32.972 0.914
R 701.08 120 33.473 0.871
R 701.08 120 33.105 1.143
R 702.03 120 36.306 1.076
R 702.04 120 36.488 0.947
R 702.05 120 35.622 0.927
R 702.05 120 35.694 0.928
R 702.06 120 36.016 0.936
R 702.06 120 36.125 0.934
R 702.08 120 36.634 0.965
R 702.08 120 36.670 0.958
R 703.04 120 32.313 0.910
R 703.04 120 32.411 0.855
R 703.05 120 32.608 0.917
R 703.06 120 32.641 0.895
R 703.07 120 32.510 0.852
R 703.08 120 32.575 0.854
R 704.04 120 32.021 0.879
R 704.04 120 32.248 0.846
R 704.05 120 31.795 0.831
R 704.05 120 32.313 0.886
R 704.07 120 32.740 0.878
R 704.07 120 32.248 0.866
R 711.07 120 32.641 0.976
R 711.07 120 32.248 1.138
R 715.04 120 32.806 1.178
R 715.03 120 32.608 0.959
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 39
R 715.05 120 32.674 1.048
R 715.05 120 32.707 1.030
R 721.06 120 31.412 0.943
R 721.06 120 31.763 1.513
R 722.05 120 33.071 1.682
R 722.07 120 34.986 0.912
R 723.05 120 35.021 1.626
V 504.29 60 18.243 0.332
V 504.29 60 18.928 0.172
V 504.29 60 18.076 0.164
V 504.3 60 18.243 0.166
V 504.3 60 18.243 0.166
V 504.3 60 18.076 0.164
V 508.29 60 17.910 0.163
V 508.29 60 17.910 0.163
V 508.29 60 17.910 0.163
V 509.29 60 17.583 0.160
V 509.29 60 17.422 0.159
V 509.29 60 17.583 0.160
V 510.3 60 16.185 0.295
V 510.3 60 16.185 0.147
V 510.3 60 16.185 0.147
V 511.26 60 18.412 0.168
V 511.26 60 18.412 0.168
V 511.26 60 18.412 0.168
V 511.28 60 18.412 0.168
V 511.28 60 18.582 0.169
V 511.28 60 18.412 0.168
V 516.31 60 18.412 0.168
V 516.31 60 18.754 0.171
V 516.31 60 18.076 0.164
V 517.24 60 18.582 0.169
V 517.24 60 18.582 0.169
V 517.24 60 18.582 0.169
V 517.25 60 18.412 0.168
V 517.25 60 18.412 0.168
V 517.25 60 18.412 0.168
V 619.2 30 25.183 0.458
V 619.2 30 24.952 0.454
V 619.21 30 25.651 0.467
V 619.21 30 24.952 0.454
V 619.22 30 23.179 0.211
V 619.22 30 23.179 0.211
V 619.22 30 23.394 0.213
V 619.22 30 23.179 0.211
V 619.23 30 23.179 0.211
V 619.23 30 23.394 0.213
V 619.23 30 23.394 0.213
V 619.23 30 23.394 0.213
V 619.24 30 23.610 0.215
V 619.24 30 23.394 0.213
V 619.25 30 23.610 0.215
V 619.25 30 23.610 0.215
V 619.26 30 23.610 0.215
V 619.26 30 23.610 0.215
V 632.98 30 28.386 0.258
V 632.98 30 28.648 0.261
V 632.99 30 29.724 0.270
40 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
V 632.99 30 28.648 0.261
V 633 30 28.386 0.258
V 633 30 28.386 0.258
V 633.01 30 27.359 0.249
V 633.01 30 27.108 0.247
V 633.01 30 26.860 0.244
V 633.01 30 26.613 0.242
V 633.01 30 26.128 0.238
V 633.02 30 26.128 0.238
V 634.98 30 22.341 0.203
V 634.98 30 22.136 0.201
V 635.1 30 26.128 0.476
V 635.1 30 25.651 0.467
V 635.12 30 28.386 0.775
V 635.13 30 29.181 0.797
V 635.13 30 28.648 1.043
V 635.13 30 28.386 1.808
V 635.14 30 29.181 0.797
V 635.14 30 26.613 0.242
V 635.14 30 26.860 0.244
V 635.14 30 27.108 0.247
V 635.15 30 26.860 0.489
V 635.15 30 26.860 0.489
V 635.16 30 26.860 0.489
V 635.16 30 26.369 0.480
V 635.16 30 26.369 0.480
V 635.16 30 26.128 0.476
V 635.17 30 25.651 0.467
V 635.17 30 26.369 0.480
V 635.18 30 26.128 0.238
V 635.18 30 26.369 0.480
V 635.19 30 26.860 0.733
V 635.19 30 26.369 0.720
V 640.21 120 27.868 0.254
V 640.21 120 27.612 0.251
V 641.1 120 32.292 0.294
V 641.11 120 31.996 0.291
V 643.21 120 28.386 0.258
V 643.21 120 28.386 0.258
V 644.1 120 29.181 0.266
V 644.1 120 28.648 0.261
V 648.2 120 28.386 0.258
V 648.2 120 28.914 0.263
V 648.21 120 28.126 0.256
V 648.21 120 28.126 0.256
V 648.22 120 30.839 1.123
V 648.22 120 29.724 0.541
V 651.08 120 33.504 0.915
V 651.08 120 32.591 0.890
V 651.2 120 32.591 0.297
V 651.2 120 33.814 0.308
V 651.21 120 32.591 0.297
V 651.22 120 32.591 0.297
V 651.23 120 32.591 0.297
V 651.23 120 32.591 0.297
V 651.24 120 32.591 0.297
V 651.24 120 32.591 0.297
V 652.07 120 34.762 0.316
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 41
V 652.08 120 34.443 0.313
V 652.2 120 31.124 0.283
V 652.2 120 30.839 0.281
V 652.21 120 31.412 0.286
V 652.21 120 31.124 0.283
V 652.23 120 31.412 0.286
V 652.23 120 31.412 0.286
V 652.24 120 31.124 0.283
V 652.24 120 31.124 0.283
V 655.02 120 25.183 0.229
V 655.02 120 25.183 0.229
V 655.2 120 32.591 0.297
V 655.2 120 32.591 0.297
V 655.21 120 32.292 0.294
V 655.21 120 32.591 0.297
V 655.22 120 32.591 0.297
V 655.22 120 32.591 0.297
V 664.2 30 34.127 0.621
V 664.2 30 34.443 0.627
V 664.21 30 35.083 0.639
V 664.21 30 27.359 0.249
V 678.02 120 35.278 0.498
V 678.02 120 35.083 0.505
V 678.03 120 34.096 0.482
V 678.03 120 34.443 0.506
V 678.05 120 33.783 0.477
V 678.05 120 33.320 0.643
V 678.06 120 33.258 0.757
V 678.06 120 33.258 0.733
V 678.08 120 32.712 0.697
V 678.08 120 32.832 0.846
V 678.09 120 33.106 0.487
V 678.09 120 31.996 1.190
V 678.11 120 32.442 1.289
V 678.11 120 32.174 1.444
V 678.12 120 31.820 0.724
V 678.12 120 31.762 1.101
V 679.07 120 33.075 0.486
V 679.08 120 33.106 0.777
V 679.09 120 30.109 0.944
V 679.1 120 29.316 0.755
V 679.13 120 32.893 0.847
V 679.13 120 31.441 0.568
V 679.14 120 31.239 1.869
V 679.15 120 31.412 0.627
V 680 120 33.075 0.486
V 680.01 120 32.501 0.490
V 680.02 120 32.382 0.625
V 680.02 120 32.772 0.482
V 680.03 120 32.144 0.803
V 680.04 120 32.382 0.646
V 680.05 120 32.263 0.856
V 680.05 120 32.742 0.537
V 680.07 120 32.115 0.472
V 680.07 120 30.726 1.273
V 680.13 120 33.014 0.485
V 680.13 120 32.832 0.483
V 681.09 120 36.805 0.785
42 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
V 681.09 120 37.282 0.821
V 681.1 120 36.300 0.852
V 681.11 120 35.967 0.650
V 681.12 120 37.111 0.985
V 681.12 120 36.635 0.807
V 682.02 120 33.474 0.518
V 682.02 120 34.096 0.491
V 682.03 120 32.292 0.456
V 682.04 120 32.292 0.475
V 682.05 120 31.908 0.451
V 682.05 120 31.732 0.491
V 682.06 120 32.471 0.861
V 682.07 120 31.908 0.494
V 682.09 120 33.474 1.049
V 682.09 120 35.408 1.139
V 682.1 120 33.846 0.770
V 682.1 120 34.127 0.728
V 682.12 120 32.412 0.810
V 682.12 120 32.681 1.051
V 683.01 120 32.352 0.784
V 683.01 120 32.115 0.497
V 683.02 120 31.762 0.723
V 683.04 120 31.499 0.860
V 683.04 120 31.211 0.564
V 683.05 120 30.641 0.450
V 683.05 120 31.355 0.461
V 684.01 120 33.350 0.735
V 684.01 120 33.474 0.473
V 684.03 120 34.666 0.920
V 684.03 120 32.681 0.919
V 684.04 120 34.507 0.997
V 684.04 120 32.561 0.915
V 684.06 120 32.651 0.816
V 684.06 120 31.996 0.874
V 689.01 120 31.849 0.507
V 689.01 120 32.233 0.486
V 689.02 120 31.996 0.470
V 689.03 120 32.352 0.476
V 690.06 120 36.434 0.536
V 690.07 120 36.872 0.555
V 690.07 120 35.769 0.526
V 690.07 120 36.266 0.533
V 690.08 120 35.473 0.549
V 690.09 120 36.000 1.070
V 690.1 120 35.670 0.891
V 690.1 120 35.375 0.911
V 691.05 120 37.351 0.578
V 691.05 120 36.974 0.557
V 691.07 120 37.145 0.560
V 691.07 120 36.838 0.542
V 692.01 120 32.233 0.486
V 692.01 120 33.014 0.526
V 692.03 120 33.412 0.481
V 692.03 120 33.412 0.481
V 692.04 120 33.908 0.556
V 692.05 120 32.412 0.466
V 692.05 120 32.471 0.467
V 692.06 120 34.570 0.508
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 43
V 692.07 120 34.634 0.498
V 692.07 120 33.566 0.483
V 692.08 120 34.285 0.493
V 692.09 120 34.570 0.508
V 692.13 120 31.879 0.846
V 692.13 120 31.557 0.837
V 693.01 120 34.411 0.602
V 693.03 120 34.826 0.695
V 693.03 120 33.628 0.484
V 693.04 120 34.002 0.541
V 693.05 120 33.939 0.488
V 693.06 120 33.443 0.481
V 693.06 120 33.628 0.484
V 693.06 120 33.136 0.477
V 693.08 120 33.535 0.505
V 693.08 120 32.953 0.484
V 693.09 120 32.832 0.593
V 693.1 120 33.075 0.498
V 693.11 120 33.228 0.600
V 693.11 120 32.712 0.894
V 693.12 120 33.197 0.488
V 693.13 120 33.535 0.493
V 694.04 120 34.890 0.513
V 694.04 120 34.762 0.511
V 694.06 120 35.278 0.546
V 694.06 120 34.666 0.510
V 694.07 120 35.343 0.520
V 694.07 120 35.703 0.525
V 694.08 120 35.083 0.516
V 694.08 120 34.987 0.514
V 694.1 120 34.954 0.982
V 694.1 120 35.703 0.525
V 694.11 120 34.222 0.515
V 694.12 120 34.285 0.504
V 694.12 120 34.159 0.515
V 694.13 120 34.443 0.506
V 694.13 120 31.732 0.448
V 695.04 120 34.285 0.504
V 695.04 120 34.507 0.507
V 695.05 120 34.033 0.500
V 695.06 120 34.064 0.501
V 695.07 120 33.939 0.511
V 695.07 120 34.096 0.527
V 695.08 120 33.721 0.496
V 695.09 120 33.721 0.496
V 696.04 120 34.602 0.509
V 696.04 120 34.762 0.511
V 696.05 120 34.826 0.512
V 696.05 120 34.316 0.505
V 696.07 120 34.507 0.520
V 696.07 120 34.666 0.715
V 696.08 120 35.019 0.515
V 696.09 120 35.703 0.689
V 699.02 120 35.245 0.518
V 699.02 120 35.506 0.914
V 699.03 120 35.310 0.519
V 699.03 120 34.411 0.506
V 699.05 120 34.348 0.505
44 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
V 699.05 120 34.538 0.508
V 699.06 120 35.083 0.516
V 699.06 120 34.666 0.510
V 699.07 120 33.814 0.497
V 699.07 120 35.148 0.517
V 699.08 120 34.602 0.509
V 699.09 120 35.148 0.517
V 699.1 120 35.604 0.523
V 699.1 120 35.441 0.521
V 700.03 120 35.868 0.527
V 700.03 120 35.441 0.521
V 700.04 120 35.525 0.530
V 700.04 120 34.922 0.513
V 700.06 120 34.634 0.522
V 700.06 120 35.019 0.527
V 700.07 120 34.380 0.505
V 700.07 120 34.634 0.669
V 700.08 120 34.253 0.504
V 700.09 120 34.890 0.610
V 700.1 120 34.858 0.845
V 700.1 120 33.908 0.511
V 701.02 120 32.203 0.513
V 701.02 120 32.501 0.490
V 701.03 120 32.292 0.486
V 701.04 120 31.791 0.479
V 701.05 120 32.501 0.490
V 701.05 120 32.712 0.972
V 701.06 120 31.326 0.585
V 701.08 120 32.115 0.852
V 701.08 120 32.893 0.484
V 702.03 120 35.051 0.515
V 702.03 120 35.834 0.527
V 702.04 120 35.769 0.526
V 702.04 120 35.148 0.517
V 702.06 120 35.736 0.525
V 702.06 120 35.901 0.716
V 702.07 120 35.571 0.809
V 702.07 120 35.245 0.531
V 703.03 120 31.211 0.459
V 703.04 120 31.703 0.916
V 703.05 120 30.613 0.740
V 703.05 120 31.470 0.739
V 703.06 120 30.924 0.541
V 703.07 120 31.879 0.595
V 703.07 120 31.791 0.747
V 703.07 120 31.067 0.468
V 704.03 120 31.239 0.459
V 704.03 120 31.067 0.457
V 704.05 120 31.239 0.459
V 704.05 120 31.239 0.666
V 704.06 120 31.441 0.474
V 704.06 120 31.470 0.445
V 704.07 120 31.616 0.590
V 704.07 120 31.268 0.498
V 710.06 120 29.669 0.447
V 710.07 120 29.154 0.601
V 711.07 120 31.586 0.765
V 711.07 120 31.674 0.941
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 45
V 715.03 120 31.703 0.592
V 715.03 120 32.442 0.990
V 715.04 120 31.820 0.771
V 715.04 120 31.967 0.638
V 721.05 120 29.806 0.678
V 721.05 120 30.248 0.710
V 722.05 120 32.591 0.695
V 722.05 120 32.681 0.590
V 723.05 120 32.115 0.754
V 723.05 120 31.820 0.724
Table A.1: Log of observations. Epoch of observations is reported in JD-
2453000.5 unit.
References
Bersanelli, M., Bouchet, P., Falomo, R, & Tanzi, E. G., 1992, AJ, 104, 28
Bertone, E., Tagliaferri, G., Ghisellini, G., et al. 2000, A&A, 356, 1
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Chincarini, G., Zerbi, F., Antonelli, A., et al. 2003, The Messenger, 113, 40
Covino, S., Stefanon, M., Fernandez-Soto, A., et al. 2004, SPIE, 5492, 1613
Chiappetti, L., Maraschi, L., Tavecchio, F., et al. 1999, ApJ, 521, 552
De Diego, J. A., Kidger, M. R., Gonzáles-Pérez, J. N., and Letho, H. J., 1997, A&A, 318, 331
Dolcini, A., Covino, S., Treves, A.,et al. 2005, A&A, 443, L33
Edelson, R., Krolik, J., Madejski, G., et al. 1995, ApJ, 438, 120
Falomo, R., Giraud, E., Maraschi, L., et al., ApJ, 1991, 380, L67
Falomo, R., Bersanelli, M., Bouchet, P., Tanzi, E. M., AJ, 1993, 106, 11
Fan, J. H. & Lin, R. G., A&A, 355, 880
Fuhrmann, L., Cucchiara, A., Marchili, N., et al. 2006, A&A, 445L, 1
Hamuy, M. & Maza, J. 1989, AJ, 97, 720
Katarzynski, K., Ghisellini, G., Tavecchio, F., et al. 2005, A&A, 433, 479
Katarzynsky, K., Ghisellini, G., Mastichiadis, A., et al. 2006, A&A, 453, 47
Katarzynski, K. & Ghisellini, G., 2006, A&A, in press [arXiv:astro-ph/0610801]
Kotilainen, J. K., Falomo, R., & Scarpa, R. 1998, A&A, 336, 479
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Mannucci, F., Basile, F., Poggianti, B. M., et al., 2001, MNRAS, 326, 745
Miller, H. R., McAlister, 1983, ApJ, 272, 26
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Pesce, J. E., Urry, C. M., Maraschi, L., et al. 1997, ApJ, 486, 770
Pian, E., Vacanti, G., Tagliaferri, G., et al. 1998, ApJ, 492, L17
Pian, E., Urry, C. M., Maraschi, L., et al. 1999, ApJ, 521, 112-120
Pian, E., Falomo, R., Hartman, R.C., et al. 2002, ApJ, 392, 407-415
Pian, E., Romano, P., Treves, A., et al. 2006, in preparation
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Sembay, S., Edelson, R., Markowitz, A., et al. 2002, ApJ, 574, 634
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46 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
Figure 13. SED of PKS 2155-304 in two states, adapted from Chiappetti et al. (1999) (see the paper for details). Data from
this work are also plotted. Filled triangles correspond to epoch 1 (13/5/2005 data), while filled hexagons belong to epoch 3 data
(20/11/2005). Optical, UV and REM data are dereddened using E(B-V)=0.026 and parameters given by Cardelli et al. (1989).
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	Introduction
	REM, Photometric procedure, data analysis
	Observations and data analysis
	Results
	Long term variability
	Short time-scale variability
	The NIR-Optical spectral energy distribution
	Discussion
	Table of observations

  Spectral variability is the main tool for constraining emission models of BL
  Lac objects. By means of systematic observations of the BL Lac prototype PKS
2155-304 in the infrared-optical band, we explore variability on the scales of
months, days and hours. We made our observations with the robotic 60 cm
telescope REM located at La Silla, Chile. VRIJHK filters were used. PKS
2155-304 was observed from May to December 2005. The wavelength interval
explored, the total number of photometric points and the short integration time
render our photometry substantially superior to previous ones for this source.
On the basis of the intensity and colour we distinguish three different states
of the source, each of duration of months, which include all those described in
the literature. In particular, we report the highest state ever detected in the
H band. The source varied by a factor of 4 in this band, much more than in the
V band (a factor ~2). The source softened with increasing intensity, contrary
to the general pattern observed in the UV-X-ray bands. On five nights of
November we had nearly continuous monitoring for 2-3 hours. A variability
episode with a time scale of ~24 h is well documented, a much more rapid flare
with t=1-2 h, is also apparent, but is supported by relatively few points.

Introduction
PKS 2155-304 (z=0.116, Falomo et al. 1991) is a prototype of high frequency peaked BL Lac objects. It has been observed in
the entire electromagnetic spectrum, from radio to TeV gamma-rays. It was the target of several multifrequency campaigns, the
main scope of which was to study the variability of the spectral energy distribution (SED), in order to constrain emission models.
In particular we refer to the 1991 and 1994 campaigns involving IUE, ROSAT, ASCA, EUVE and ground based telescopes
(see Edelson et al. 1995, Urry et al. 1997, and references therein). There were noticeable differences in source behaviour between
these two epochs. While in 1991 the multiwavelength variability was almost achromatic, and the X-ray variation led that in the
UV by a couple of hours, in 1994 the variability was more pronounced in X-rays than in UV-optical, with a lag of the latter
⋆ This paper is the corrected version astroph 0704.0265 published in A&A 469 503. It contains the material in the ”Errata Corrrige”, in press
in A&A.
http://arxiv.org/abs/0704.0265v2
2 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
Period of observation Nights of observation Number of photometric points Total exposure time
May 6 129 14520 s
September 8 159 18080 s
October 3 102 11590 s
November 21 1581 173540 s
December 6 64 7030 s
Table 1. Outline of observations accomplished in 2005.
by two days. The general pattern was that of a hardening of the spectrum with increasing intensity. More recently Zhang et al.
(2006b) studied a large set of data covering the period 2000-2005 obtained with the XMM-Newton satellite, which allowed a
direct comparison of the X-ray and UV-optical band, the latter deriving from the Optical Monitor on board the satellite. The
complexity of the variability pattern is confirmed. Some episodes of achromatic variation were detected, but a general tendency
of increasing variability amplitude with increasing frequency, and spectral hardening with increasing intensity was found.
Optical photometry has been performed by several groups in several occasions (see e.g. Miller et al. (1983), Smith et al.
(1992), Xie et al. (1996), Paltani et al. (1997), Pesce et al. (1997), Fan & Lin (2000), Tommasi et al. (2001) and references
therein). All this material is rather fragmented, consisting of few hours of observations during few nights. The difficulty of a
systematic observing campaign covering many nights is partly overcome by the possibility of observing using remotely guided
or robotic telescopes.
The REM telescope, originally designed for a prompt detection of gamma ray bursts (see Molinari et al. (2006)), is particularly
apt for photometric studies of BL Lacs (see also the previous results for PKS 0537-441 by Dolcini et al. 2005, and for 3C 454.3
by Fuhrmann et al. 2006) and, being located at La Silla (Chile), it is ideally fit to study PKS 2155-304.
We report on extensive and intensive photometric campaign performed in 2005 in the V, R, I, J, H, K bands. For the total
number of photometric points, for the time resolution (minutes) and spectral range this campaign seems to supersede all the
IR-optical photometric material presented thus far.
2. REM, Photometric procedure, data analysis
2.1. REM
The Rapid Eye Mount (REM) Telescope is a 60 cm fully robotic instrument. It has two cameras fed at the same time by a dichroic
filter that allows the telescope to observe in the NIR (z’, J, H, K) as well as optical (I, R, V). Further information on the REM
project may be found in Zerbi et al. (2001), Chincarini et al. (2003) and Covino et al. (2004).
2.2. Observations and data analysis
REM observed the PKS 2155-304 field during May, September, October, November and December 2005 in VRIH bands. Only
during three nights in September the telescope observed also in J and K filters. To allow intranight and short time-scale variability
monitoring, very intensive observations (2-3 h, quasi-continuously) were made during five of the nights in November. An outline
of the observations is reported in Table 1, while the complete log is only available in Table A.1 (see Appendix A): we report for
each photometric point the band, the epoch, the integration time, the intensity and its uncertainty. Typical integration times are
≤100 s and statistical uncertainties are always ≤ 10% and ≤ 3% in the highest state (November 2005, see following).
Reduction of the REM NIR and optical frames followed standard procedures. Photometric analysis of the frames was done
using the GAIA1 and DAOPHOT packages (Stetson 1986). Relative calibration was obtained by calculating magnitude shifts
relative to three bright isolated stars in the field, indicated by A, B, C in Fig. 1 (image taken from ESO Digitized Sky Survey2).
The NIR frames were calibrated using the magnitudes of the A, B and C stars as reported in the 2MASS catalogue3. For the
optical, we exposed on 2006 June 29 the standard field G156-31 (Landolt, 1992), and immediately after this the PKS 2155-304
field. We calculated the zero points which were then used to calibrate all of our data. The observed magnitudes in the REM filters
for the reference objects A, B, and C are reported in Table 2. We have monitored the relative intensities of the A, B, C reference
stars during the entire observation period, and we have detected no indication of variability within 0.1 mag (error on the average
≤0.01 mag).
1 http://star-www.dur.ac.uk/ pdraper/gaia/gaia.html
2 http://archive.eso.org/dss/dss
3 http://irsa.ipac.caltech.edu
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 3
Figure 1. PKS2155-304 field (DSS-1 survey). Letters indicate stars used for calibration.
A B C
RA 21:58:46.505 21:58:43.807 21:58:42.337
DEC -30:17:51.29 -30:17:15.71 -30:10:27.41
K 11.171±0.024 12.475±0.030 12.648±0.024
H 11.182±0.027 12.556±0.026 12.769±0.027
J 11.510±0.027 12.838±0.026 13.091±0.029
I 12.184±0.005 13.421±0.009 13.216±0.006
R 12.981±0.004 13.434±0.006 13.671±0.010
V 13.179±0.005 13.822±0.009 13.899±0.013
Table 2. Coordinates, IR and optical magnitudes for the reference stars.
Note that we found significant deviations from the optical calibrations provided by the finding charts for AGN of the
Heidelberg University4 (Hamuy & Maza, 1989). In particular the star C is also used as a calibrator by these authors and our
optical zeropoint differs by about 0.3 mag from theirs.
Relative and absolute calibration errors have been added in quadrature to the photometric error derived from the procedure.
3. Results
3.1. Long term variability
In this section we report the results of the long term photometric analysis. The light curves in the H, R, I, V filters are given in
Fig. 2.
The intensity is normalized with respect to the average over the entire observation period. These averages are given in Table
3. It is immediately apparent that the total variability range is very different in the various filters, being a factor ≈ 4 in H and a
factor ≈ 2 in V (see Table 3) . The shapes of the light curves are similar in the various filters. A flare-like structure is apparent
in all filters at t ≈ 680 (first days of November). The ratio between the V- and H-band fluxes, designated as V/H, is reported in
Fig. 3. In order not to introduce spurious effects due to small time scale variability, the V/H ratio has been computed for pairs of
V and H measurements spaced apart in time by no more than 10 minutes.
It seems that there are two main colour states: the source softens rather abruptly, in response to the November flare. On
the basis of the light curve and the colour curve we divide the observations in three epochs: 1 500-525, 2 640-660, 3 670-725,
expressed in MJD5.
4 http://www.lsw.uni-heidelberg.de/projects/extragalactic/charts/2155-304.html
5 For the Modified Julian Date we use the convention MJD=JD-2,453,000.5
4 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
500 550 600 650 700
500 550 600 650 700
500 550 600 650 700
H filter
I filter
R filter
V filter
500 550 600 650 700
Figure 2. Normalized light curves of PKS 2155-304. Flux is reported in arbitrary unit (a. u.). In each boxes a typical error bar is
plotted.
Filter H I R V
Average 114.9±3.3 34.45±6.5 30.89±5.13 30.70±5.05
Max value 156.5 46.4 38.3 37.4
Min value 36.5 19.1 16.2 16.2
Average ep.1 39.3±1.4 21.4±1.5 18.7±1.3 18.1±0.7
Average ep.2 65.9±5.2 28.4±3.3 27.2±2.5 20.3±3.4
Average ep.3 122.9±6.1 38.8±1.9 34.1±1.5 33.5±1.7
Table 3. Average intensities for all epochs and all filters. All data are in mJy units. Epoch 1 corresponds to May 2005 observa-
tions, epoch 2 to September-October 2005 observations and epoch 3 to November-December 2005 observations.
3.2. Short time-scale variability
We report in Fig. 4 the light curves for five nights in November 2005, when the observations were more intensive. All the nights
belong to epoch 3, corresponding to the high state of the source.
The mean intensity and the 1-sigma values for each night are given in Table 4.
A χ2 analysis indicates that in each night the significance of variability is very high, but for the nights of Nov 4 and Nov 18
for the H band and Nov 19 for the V band. In the box of Nov 4 - V band we also report the photometry of a comparison star
which illustrates directly the significance of the source variability. Though the shapes of intensity curves are different (see Fig.
4), there is a rather regular colour-intensity dependence (see Fig. 5) indicating harder states for higher intensities.
We adopt the usual definition of time scale variability τ = 11+z
d f/dt . Following Montagni et al. (2006), a variability time scale
is taken as reliable if the light curve can be approximated with a linear dependence, and it contains at least 10 points. In particular
this gives a time scale of ≈ 24 h for the November 4 night (Fig. 4, V band - Nov 4 box). The simultaneous H light curve does
not show any regular variability. We note that on November 8 in the H curve there is a flare-like event. If one connects 4 points
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 5
Time (MJD)
500 525 550 575 600 625 650 675 700 725
Figure 3. V/H flux ratio evolution during 2005. Error bars are comparable with symbol size.
Figure 4. Light curves in the H and V filters for five nigths in November 2005, when the observations were more intensive. Dates
of observations are reported in each box. The solid line in V band - 4 Nov box results from a linear regression analysis. The solid
line in H band - 8 Nov box connects the four points of the flare-like structure. In each box it is given a typical error bar. In V
band - 4 Nov box the light curve of one comparison star is also plotted, with a fixed enhancement of 9 mJy.
6 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
Figure 5. V/H flux ratio versus intensity for the five more intensively observed nights of epoch 3. In each box a typical error bar
is plotted.
Night 4/11 8/11 18/11 19/11 20/11
Average H 119.3±1.7 119.3±3.0 120.4±2.1 124.5±2.8 130.8±3.0
Average I 39.1±0.6 36.4±0.5 38.7±0.6 38.7±0.6 38.3±0.7
Average R 38.5±0.8 36.40±.8 37.3±0.5 38.0±1.6 37.1±0.5
Average V 33.2±1.1 33.0±1.1 33.4±1.1 33.5±1.1 34.7±0.1
Table 4. Average intensities and 1-sigma values for all filters for all five nights with more intensive observations in November
2005. All values are in mJy units.
as suggested in Fig. 4 H band - Nov 8 box, the time scale variability is as short as 1.5 h. Unfortunately the V light curve is too
sparse to confirm the presence of the flare also in this band.
3.3. The NIR-Optical spectral energy distribution
We had six filter coverage (K,H,J,I,R,V) during three nights of Sept. 2005 (epoch 2) and representative SEDs for these nights are
reported in Fig. 6.
The delays between exposures in the different filters are less than 20 minutes. Reddening corrections are less than 6% in V
and have been neglected. A fit with a single power law yields α ≈0.9 and it is clearly not good. The main deviation derives from
the J filter, exceeding substantially our photometric precision of about 10%. An improvement in the fit is obtained by using a
broken power law with spectral indices α ≈0.4 for the IR data and α ≈0.9 for the optical data.
For comparison, we report in Fig. 7 the SED of June 29, 2006, exposure used for calibration purpose: its profile is rather
similar to that of Sept. 2005.
At the other epochs the SED consists of 4 points (H, I, R, V), and in Figs. 8 and 10 we give representative examples of SEDs
acquired on epoch 1 and 3. The time differences between observations at various filters are less than 20 minutes.
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 7
Frequency (Hz)
19/9 data
21/9 data
26/9 data
Average data
Figure 6. September 2005 spectra for observations including the K and J filters. The spectral fit on average data with a single
power law yields a spectral index α=0.91±0.07.
Frequency (Hz)
Figure 7. 29 June 2006 spectrum. The spectral fit with a single power law yields a spectral index α=0.90±0.16.
In Fig. 8, which refers to a low state, we report also the estimated contribution of the host galaxy, which was calculated
adopting the H magnitude of the galaxy measured by Kotilainen et al. (1998) and the Mannucci at al. (2001) template spectrum
for giant ellipticals. It is apparent that the contribution of the galaxy never exceeds 20% of the BL Lac signal. At the other epochs
the contribution from galaxy is negligible and it is not relevant for explaining the excess in J with respect a single power law
noted above. The epoch 2 photometry (Fig. 9) is compared with spectrophotometry obtained with the ESO 3.6m telescope by R.
Falomo6 on July 25, 2001 (Sbarufatti et al. (2006)). The source was found in a similar, but somewhat lower brightness state and
some deviations from a power law are apparent. The HRIV points at epoch 3 (Fig. 10) are roughly fitted by a single power law
of α ≈1.3. In any case the comparison of the SEDs at the three epochs clearly indicate a softening with increasing intensity.
6 spectrum available at the ZBLLAC online library, http://www.oapd.inaf.it/zbllac
http://www.oapd.inaf.it/zbllac
8 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
Figure 8. 13 May 2005 spectrum - epoch 1. We report also the spectrum of the host galaxy (see text). The spectral fit with a
single power law yields a spectral index α=0.77±0.16.
Figure 9. 19 September 2005 spectrum - epoch 2. For comparison we report the ESO 3.6m telescope spectrophotometry which
correspond to a slightly lower state of the source. The spectral fit with a single power law yields a spectral index α=0.88±0.05.
4. Discussion
A collection of near-IR/optical SEDs of PKS2155-304 obtained by various authors at different epochs is presented in Fig. 11 and
in Table 5. Our data encompass all those reported in the literature.
In the historical observations of PKS2155-304 the delays between exposures at different filters are typically of the order of
hours, instead of about 10 minutes as in our data set. Comparing literature data with our data it is apparent that the maximum
we observed on 20 November 2005 in the H filter light curve is the highest state ever reported in this band. Note that the V state
was comparable with states reported in the literature, likely because the coverage of the source in the optical band is less sparse
than that in the NIR. A most noticeable result of our photometry is the discovery of long term H-band variability, the amplitude
of which is much larger than that in the optical.
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 9
Frequency (Hz)
Figure 10. 4 November 2005 spectrum - epoch 3. The spectral fit with a single power law yields a spectral index α=1.32±0.25.
Error bars are comparable with symbols size.
Data set α V (mJy)
This work (13/5/2005) 0.77±0.16 16.485±0.263
This work (19/9/2005) 0.88±0.05 24.370±0.238
This work (4/11/2005) 1.32±0.24 35.278±0.498
Bertone at al. (2000) 0.42±0.26 26.20±0.58
Pesce et al. (1997) 0.62±0.30 24.50±0.67
Zhang & Xie (1996) 0.62±0.16 22.90±0.63
Bersanelli et al. (1992) 0.61±0.38 51.88±1.56 (J band)
Treves et al. (1989) (1/12/1983) 0.51±0.31 19.80±0.36
Treves et al. (1989) (11/11/1984) 0.51±0.41 26.20±0.48
Miller & McAlister (1983) 0.62±0.56 17.8
Table 5. Spectral index values and V values for all spectra plotted in Fig. 11. α vs V plot is reported in Fig. 12.
In Fig. 12 we plot the spectral index vs the V magnitude, as reported in table 5. There is no apparent correlation. It is
noticeable however that the highest state in all bands (our observation of Nov 2005) corresponds to a rather soft spectral shape.
This contrasts with the usual source behaviour of hardening with increasing intensity, as found in the UV-X-ray band (see
Introduction). It contrasts also with the short time scale variability, as reported in section 3.2.
There is a general consensus that the blazar SED can be explained by the superposition of a synchrotron component, and
an inverse Compton one due either to scattering off the synchrotron photons (synchrotron-self Compton, SSC), or to external
photons like those of the broad line region or of a thermal disk (e.g. Tavecchio et al. 1998, Katarzynski et al. 2005). This results
in a typical two-maxima shape of the blazar SED. In Fig. 13 we report examples of the SED modeling proposed for PKS 2155-
304, on the basis of data taken in 1997. The models are detailed in Chiappetti et al. (1999). The object is a typical HBL, with the
synchrotron peak in the soft X-rays.
A well known critical point of this model, is that the source size is essentially constrained by variability, and variability itself
requires that the SED is constructed using simultaneous observations in all bands. A further step of the modelling consists in
identifying the physical origin of the relativistic jet and of its variability, see e.g. Katarzynski & Ghisellini (2006). With this
premise it is obvious that the optical-IR photometric study, non simultaneous with that in other regions of the SED, has only a
limited relevance in clarifying the overall picture. However we would like to make some remarks. If the SSC models reported in
Fig. 13 truly represent the behaviour of the SED in 1997, as suggested by the good match with the X-ray and TeV energy data,
and if our 2005 optical-IR spectra are also due to the SSC mechanism, then the latter represent a different condition in the jet
and point to different critical parameters within the SSC scenario. While the IR-optical spectrum in May 2005 (triangles) has
the same shape as predicted in 1997, but different normalization, the November 2005 IR-optical spectrum is different in both
10 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
This work (13/5/2005)
This work (19/9/2005)
This work (4/11/2005)
Bertone et al. 2000 (24/5/1996)
Pesce et al. 1997 (19/5/1994)
Zhang and Xie 1996 (5/7/1994)
Bersanelli et al. 1992 (17/1/1987)
Treves et al. 1989 (1/12/1983)
Treves et al. 1989 (11/11/1984)
Miller and McAlister 1983 (19/11/1981)
Frequency (Hz)
Figure 11. Different spectra of PKS2155-304 from observations at other epochs reported in the literature. Symbols correspond
to following works: filled circles: this work (13/5/2005 data), filled squares: this work (19/9/2005 data), filled up triangles: this
work (4/11/2005 data), open diamonds: Bertone et al. (2000; 24/5/1996 data), open circles: Pesce et al. (1997; 19/5/1994 data,
the Hamuy & Maza (1989) calibration is used), open up triangles: Zhang and Xie (1996; 5/7/1994 data), open squares: Bersanelli
et al. (1992; 17/1/1987 data), open crosses: Treves et al. (1989; 1/12/1983 data), open stars: Treves et al. (1989; 11/11/1984 data),
asterisks: Miller and McAlister (1983; 19/11/1981 data). Spectral index values and V magnitudes for all data sets are reported in
Table 5.
shape and normalization. The May 2005 observation suggests that the synchrotron peak may be located at a frequency similar to
the one observed in 1997 (approximately between extreme UV and soft X-rays), the total energy being somewhat higher (about
a factor 2, see Figure 13) than observed in 1997. The slope of the November 2005 spectrum suggests instead a much lower
synchrotron peak energy, around the IR-optical domain or even redward, i.e. about 2-3 orders of magnitude lower than observed
in 1997 and inferred in May 2005. While a variation of the synchrotron peak energy of this amplitude and on this time scale
(the September 2005 slope is intermediate between those of May and November 2005, suggesting a monotonic change) it is not
unprecedented in blazars (Mkn501 exhibited a similar variation in a much more rapid time scale, Pian et al. 1998), this would be
the first observation of this kind in PKS 2155-304. Therefore, our interpretation is only tentative, although supported by the large
observed IR variability.
Alternatively, in order to explain the optical-IR flux excess we observe in 2005 with respect to the SSC prediction based on
the earlier multiwavelength data (Fig. 13), one could invoke a thermal component, possibly from hot dust associated with the
“dusty torus” surrounding the central region of the active nucleus, as suggested in the cases of other blazars with excess in the
optical-infrared band (De Diego et al. 1997, for blazar 3C 66A; Pian et al. 1999 for 3C 279; Pian et al. 2002, 2006, for blazar
PKS 0537-441). However, this seems somewhat less likely, because high emission states, as observed by us, are expected to be
dominated by non-thermal beamed relativistic radiation.
The continuation of this and other similar optical-IR studies, which have been proven to be promising but do not provide
enough information for a physical interpretation of the data, requires that the observations are extended to other wavelengths.
Simultaneous observations over a large wavelength range is the only tool to provide the necessary information for a physical
interpretationof the observed variability of blazars. REM monitorings of the kind reported here could be an effective trigger to
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 11
V (mJy)
15 17.5 20 22.5 25 27.5 30 32.5 35
Figure 12. α vs V plot for data reported in Fig. 11. Symbols are the same as used in Fig. 11.
X-ray satellites, and programs along these lines are foreseen with SWIFT. Cross correlation procedures, which up to now have
been limited mainly to the X-ray band (Zhang et al. 2005, 2006a, 2006b, Sembay et al. 2002, Edelson et al. 1995), would be
extended to a much larger portion of the SED.
Appendix A: Table of observations
Filter Epoch (MJD) Integr time s Intensity mJy Sigma
K 633.4872 120 73.993 3.640
K 633.4966 120 73.345 3.640
K 633.5012 120 73.382 2.938
K 633.5094 120 76.417 1.043
K 633.5254 120 72.309 2.698
K 635.4835 120 70.598 2.579
K 635.6612 120 66.373 2.810
K 635.6670 120 67.794 2.548
K 635.6736 120 67.857 2.096
K 635.6794 120 69.182 2.758
K 635.6832 120 66.987 2.263
K 639.8339 120 67.982 0.689
K 639.8355 120 67.345 0.702
H 503.7708 120 38.943 3.048
H 503.7723 120 39.412 2.977
H 503.7741 120 38.907 2.903
H 503.8028 120 40.628 3.180
H 503.8043 120 43.135 7.497
H 507.7738 120 38.373 0.314
H 507.7753 120 38.302 0.314
H 507.7839 120 38.692 0.317
H 507.7854 120 38.586 0.316
12 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 507.7873 120 38.835 0.601
H 507.7881 120 38.871 0.318
H 508.7487 120 37.881 1.999
H 508.7501 120 37.224 2.168
H 508.7516 120 37.771 2.127
H 508.7531 120 38.444 1.924
H 508.7549 120 37.847 1.146
H 508.7565 120 37.396 1.786
H 510.6465 120 39.339 2.005
H 510.7174 120 39.850 1.559
H 510.7192 120 39.557 1.584
H 510.7208 120 39.594 1.513
H 510.7229 120 40.274 1.466
H 510.7244 120 40.071 1.240
H 510.7379 120 39.484 1.258
H 510.7394 120 39.740 1.555
H 510.7413 120 39.960 1.382
H 510.7427 120 39.412 1.399
H 510.7448 120 40.219 2.635
H 510.7463 120 40.256 1.246
H 514.7073 120 38.799 1.271
H 514.7089 120 38.056 1.247
H 514.7107 120 38.515 1.297
H 514.7122 120 38.267 1.741
H 514.7143 120 37.881 1.379
H 514.7156 120 38.887 1.415
H 514.7068 120 37.881 2.448
H 514.7710 120 37.812 1.342
H 514.7734 120 37.259 1.288
H 514.7749 120 36.478 1.162
H 515.6989 120 40.929 2.272
H 515.7003 120 40.108 2.117
H 515.7022 120 40.966 2.833
H 515.7037 120 41.155 2.210
H 515.7085 120 40.703 3.926
H 515.7086 120 41.422 2.149
H 515.7091 120 41.042 2.316
H 515.7106 120 41.117 2.320
H 515.7124 120 41.498 2.266
H 515.7139 120 40.816 2.117
H 635.3400 120 61.436 2.148
H 635.3489 120 63.801 0.405
H 635.3552 120 63.566 0.794
H 635.3648 120 62.349 0.855
H 637.5426 120 57.494 0.952
H 637.5481 120 57.334 1.721
H 637.5502 120 57.230 1.591
H 637.5619 120 55.928 1.162
H 637.5779 120 55.671 1.427
H 642.6039 120 59.597 1.427
H 642.6054 120 59.597 1.394
H 643.4546 120 61.267 0.902
H 643.4561 120 61.948 0.509
H 643.4581 120 62.119 1.031
H 643.4596 120 62.925 1.627
H 643.4607 120 61.663 0.741
H 643.4631 120 62.607 0.992
H 645.5581 120 64.095 1.014
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 13
H 645.5622 120 65.528 1.049
H 645.5641 120 64.036 1.104
H 645.5655 120 63.860 2.105
H 646.4435 120 60.873 2.048
H 646.4464 120 60.817 2.036
H 646.4490 120 60.482 2.044
H 646.4510 120 60.705 3.685
H 646.4521 120 62.291 2.194
H 646.4536 120 61.834 3.389
H 650.5509 120 64.213 2.708
H 650.5524 120 66.134 2.500
H 650.5537 120 64.036 3.012
H 650.5552 120 62.810 5.245
H 650.5571 120 65.047 3.372
H 650.5586 120 64.629 2.247
H 650.5606 120 63.449 2.176
H 650.5621 120 65.770 2.425
H 650.5641 120 66.256 2.454
H 650.5709 120 64.808 4.160
H 650.5743 120 64.692 2.418
H 655.3672 120 73.253 2.759
H 655.3688 120 72.048 1.800
H 655.3708 120 71.322 1.508
H 655.3716 120 71.916 1.493
H 655.3741 120 71.718 1.505
H 655.3756 120 73.312 1.762
H 655.3772 120 71.454 1.996
H 655.3787 120 71.257 1.886
H 655.5449 120 71.652 1.500
H 655.5464 120 71.652 1.695
H 655.5481 120 70.474 1.475
H 655.5496 120 70.799 1.482
H 655.5515 120 71.191 1.490
H 655.5530 120 71.718 1.501
H 655.5548 120 72.115 1.641
H 655.5563 120 71.718 1.566
H 655.5581 120 72.381 2.305
H 655.5596 120 72.448 1.516
H 655.5615 120 71.536 1.562
H 655.5630 120 71.060 1.552
H 655.5648 120 71.652 1.565
H 655.5663 120 71.454 1.561
H 655.5681 120 71.119 1.620
H 655.5696 120 70.799 2.577
H 665.3660 120 118.912 3.138
H 678.3451 120 121.458 1.503
H 678.3466 120 116.957 1.524
H 678.3480 120 117.173 1.628
H 678.3501 120 121.458 1.687
H 678.3516 120 120.455 1.491
H 678.3531 120 121.570 1.689
H 678.3551 120 117.497 1.821
H 678.3566 120 120.123 3.080
H 678.3581 120 119.902 1.562
H 678.3604 120 121.123 2.447
H 678.3619 120 117.822 1.971
H 678.3634 120 119.131 1.601
H 678.3656 120 120.012 1.932
14 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 678.3671 120 119.571 1.661
H 678.3685 120 119.022 2.584
H 678.3707 120 119.681 1.927
H 678.3723 120 117.065 1.885
H 678.3738 120 117.931 1.460
H 678.3759 120 118.366 1.500
H 678.3774 120 118.584 1.593
H 678.3788 120 118.366 1.767
H 678.3811 120 118.803 1.506
H 678.3826 120 118.803 1.470
H 678.3840 120 118.803 1.470
H 678.3862 120 117.822 1.493
H 678.3877 120 118.693 2.064
H 678.3892 120 117.931 1.760
H 678.3911 120 117.931 1.638
H 678.3926 120 119.022 1.653
H 678.3942 120 119.902 1.790
H 678.3963 120 118.475 1.466
H 678.3978 120 118.039 1.461
H 678.3993 120 118.257 1.765
H 678.4014 120 118.039 1.461
H 678.4028 120 117.605 1.968
H 678.4043 120 118.912 1.472
H 678.4064 120 120.123 1.728
H 678.4078 120 121.123 1.499
H 678.4093 120 119.792 2.164
H 678.4114 120 118.584 2.225
H 678.4128 120 117.281 1.528
H 678.4143 120 117.281 2.457
H 678.4164 120 117.497 1.754
H 678.4178 120 115.140 1.500
H 678.4193 120 119.022 1.776
H 678.4214 120 117.822 1.535
H 678.4218 120 118.257 1.643
H 678.4244 120 115.352 1.503
H 678.4265 120 118.912 1.711
H 678.4280 120 116.098 1.437
H 678.4294 120 120.900 1.496
H 678.4346 120 119.131 1.601
H 678.4362 120 120.677 2.019
H 678.4376 120 120.677 1.494
H 678.4398 120 120.789 1.495
H 678.4412 120 120.566 3.387
H 678.4427 120 121.123 2.359
H 678.4447 120 122.019 1.891
H 678.4462 120 120.789 1.495
H 678.4476 120 120.344 2.092
H 678.4497 120 120.900 2.811
H 678.4512 120 121.794 2.372
H 678.4526 120 121.794 2.372
H 678.4546 120 120.012 2.605
H 678.4562 120 120.566 3.189
H 678.4576 120 121.906 1.693
H 678.4597 120 121.458 1.882
H 678.4612 120 122.582 2.214
H 678.4626 120 121.794 1.887
H 682.3480 120 118.693 1.260
H 682.3495 120 117.497 1.152
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 15
H 682.3510 120 116.634 3.660
H 682.3532 120 119.681 1.270
H 682.3547 120 119.681 1.270
H 682.3562 120 119.131 3.121
H 682.3583 120 119.351 1.170
H 682.3597 120 117.822 1.155
H 682.3618 120 118.693 1.163
H 682.3633 120 118.257 1.851
H 682.3647 120 118.257 1.159
H 682.3669 120 118.366 2.313
H 682.3684 120 117.173 1.192
H 682.3700 120 116.420 1.575
H 682.3721 120 116.420 1.184
H 682.3735 120 118.803 1.689
H 682.3771 120 116.527 3.454
H 682.3771 120 117.389 1.246
H 682.3785 120 117.389 1.246
H 682.3801 120 117.497 1.928
H 682.3821 120 119.681 1.329
H 682.3836 120 120.900 1.556
H 682.3735 120 120.677 1.183
H 682.3872 120 118.148 1.254
H 682.3887 120 119.902 1.175
H 682.3903 120 117.713 1.757
H 682.3917 120 118.693 1.260
H 682.3938 120 117.065 1.747
H 682.3953 120 119.131 2.328
H 682.3968 120 118.148 2.121
H 682.3989 120 116.849 2.006
H 682.4005 120 116.634 2.662
H 682.4019 120 119.131 1.693
H 682.4041 120 121.011 1.284
H 682.4055 120 118.257 2.216
H 682.4070 120 119.351 3.641
H 682.4156 120 120.234 1.547
H 682.4171 120 122.695 2.299
H 682.4186 120 125.900 3.406
H 682.4222 120 132.198 2.373
H 682.4257 120 119.571 3.235
H 682.4271 120 118.693 5.296
H 682.4305 120 120.677 4.421
H 682.4324 120 119.571 3.235
H 682.4338 120 121.011 1.284
H 682.4359 120 117.931 1.310
H 682.4374 120 118.803 1.860
H 682.4388 120 121.682 1.418
H 682.4398 120 123.488 5.620
H 682.4412 120 123.148 1.666
H 682.4427 120 120.012 4.503
H 682.4449 120 119.571 1.464
H 682.4464 120 113.143 1.319
H 682.4479 120 114.189 2.702
H 682.4500 120 120.344 1.549
H 682.4506 120 122.582 1.830
H 682.4543 120 118.039 2.596
H 682.4558 120 126.714 1.551
H 682.4573 120 123.375 7.051
H 683.3333 120 114.611 0.668
16 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 683.3348 120 112.312 1.052
H 683.3363 120 114.717 0.985
H 683.3385 120 112.002 0.653
H 683.3401 120 112.105 0.653
H 683.3415 120 113.560 0.662
H 683.3435 120 113.770 1.442
H 683.3451 120 113.665 0.662
H 683.3466 120 115.885 1.568
H 683.3486 120 113.770 0.809
H 683.3501 120 114.505 0.737
H 683.3516 120 113.665 0.808
H 683.3535 120 113.143 0.804
H 683.3551 120 117.605 0.685
H 683.3566 120 114.400 1.258
H 683.3585 120 115.140 0.671
H 683.3600 120 116.849 0.681
H 683.3616 120 117.065 1.005
H 683.3636 120 112.519 0.656
H 683.3651 120 115.246 0.819
H 683.3666 120 112.830 0.802
H 683.3687 120 115.034 0.818
H 683.3702 120 114.928 0.740
H 683.3717 120 113.979 1.739
H 683.3739 120 114.190 0.812
H 683.3754 120 112.934 0.727
H 683.3769 120 115.565 2.991
H 683.3795 120 112.519 1.054
H 683.3810 120 118.584 0.691
H 683.3826 120 114.400 0.736
H 683.3845 120 112.416 2.109
H 683.3860 120 115.459 0.991
H 683.3875 120 114.084 0.811
H 683.3889 120 115.034 0.740
H 683.3904 120 113.665 0.890
H 683.3920 120 116.527 0.750
H 684.3339 120 120.234 1.488
H 684.3353 120 119.681 1.662
H 684.3368 120 121.123 1.743
H 684.3389 120 119.571 1.558
H 684.3403 120 119.792 1.561
H 684.3441 120 119.681 1.662
H 684.3456 120 122.695 2.570
H 684.3470 120 123.148 1.983
H 684.3484 120 123.148 1.983
H 684.3505 120 119.792 1.929
H 684.3519 120 121.682 1.585
H 684.3541 120 120.900 1.624
H 684.3556 120 122.356 1.700
H 684.3571 120 122.356 1.514
H 684.3591 120 120.123 1.487
H 684.3606 120 120.900 1.532
H 684.3621 120 121.682 2.641
H 684.3644 120 120.789 1.945
H 684.3660 120 121.011 1.577
H 684.3674 120 121.682 3.418
H 684.3696 120 116.205 1.514
H 684.3711 120 122.244 1.698
H 684.3726 120 122.131 2.291
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 17
H 684.3748 120 122.356 1.514
H 684.3762 120 120.234 3.279
H 684.3777 120 123.034 1.653
H 684.3798 120 122.808 2.055
H 684.3813 120 123.034 1.523
H 684.3828 120 124.059 1.536
H 684.3848 120 122.808 1.767
H 684.3863 120 121.906 2.646
H 684.3878 120 124.516 2.896
H 684.3898 120 122.582 1.517
H 684.3912 120 122.019 1.639
H 684.3927 120 122.469 1.596
H 684.3948 120 124.861 1.627
H 684.3962 120 123.602 1.778
H 684.3977 120 121.123 1.808
H 685.3274 120 125.091 1.945
H 685.3289 120 121.346 1.851
H 685.3303 120 127.769 2.978
H 685.3324 120 120.123 1.803
H 685.3409 120 119.792 3.144
H 685.3424 120 116.957 2.644
H 685.3439 120 117.389 2.202
H 685.3459 120 113.770 2.201
H 685.3474 120 117.389 2.202
H 685.3489 120 114.084 2.500
H 685.3510 120 114.506 2.358
H 685.3525 120 118.803 1.888
H 685.3540 120 115.352 2.038
H 685.3561 120 115.992 1.741
H 685.3575 120 116.313 1.746
H 685.3590 120 114.295 1.715
H 685.3610 120 115.459 1.795
H 685.3625 120 117.605 2.206
H 685.3639 120 118.257 3.015
H 685.3660 120 116.527 1.778
H 685.3676 120 119.022 2.451
H 685.3690 120 115.885 2.386
H 685.3711 120 116.420 2.397
H 685.3726 120 115.671 1.838
H 685.3740 120 115.992 1.741
H 685.3761 120 116.527 1.947
H 685.3776 120 119.461 1.793
H 685.3790 120 115.246 1.979
H 685.3810 120 117.822 1.768
H 685.3825 120 114.928 2.223
H 685.3840 120 117.497 1.763
H 689.3300 120 121.682 1.856
H 689.3315 120 120.900 1.844
H 689.3330 120 119.792 1.827
H 689.3351 120 120.344 1.913
H 689.3365 120 116.205 1.995
H 689.3380 120 119.792 1.827
H 689.3401 120 118.039 1.972
H 689.3423 120 120.455 2.723
H 689.3438 120 119.461 1.858
H 689.3458 120 121.794 2.035
H 689.3473 120 119.902 2.003
H 689.3487 120 121.011 2.138
18 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 689.3508 120 119.681 1.861
H 689.3523 120 117.822 1.797
H 689.3537 120 117.931 1.799
H 689.3557 120 123.034 2.055
H 689.3572 120 118.912 4.965
H 689.3586 120 118.584 2.095
H 690.3843 120 135.402 1.676
H 690.3857 120 130.866 8.745
H 690.3892 120 156.468 6.088
H 690.3907 120 133.791 6.165
H 690.3922 120 132.442 1.543
H 690.3943 120 132.809 1.209
H 690.3958 120 131.712 1.072
H 690.3972 120 131.470 1.196
H 690.3994 120 134.408 1.094
H 690.4009 120 136.278 1.109
H 690.4023 120 133.668 3.077
H 690.4044 120 133.545 1.146
H 690.4059 120 136.530 1.111
H 690.4073 120 136.153 1.891
H 690.4094 120 136.781 1.499
H 690.4109 120 132.686 1.207
H 690.4124 120 133.422 1.145
H 690.4144 120 134.532 1.224
H 690.4158 120 135.278 1.393
H 690.4172 120 134.161 1.221
H 690.4193 120 135.902 2.436
H 690.4208 120 134.904 1.158
H 690.4222 120 137.666 2.020
H 690.4244 120 138.047 2.360
H 690.4259 120 133.791 1.217
H 690.4274 120 137.160 1.905
H 690.4297 120 136.404 1.171
H 690.4309 120 135.153 0.992
H 690.4324 120 138.812 1.521
H 691.3710 120 131.955 1.019
H 691.3724 120 123.148 2.555
H 691.3739 120 133.668 2.891
H 691.3760 120 135.777 2.111
H 691.3774 120 150.531 4.325
H 691.3789 120 134.285 1.639
H 691.3812 120 133.176 2.647
H 691.3827 120 135.527 1.334
H 691.3842 120 132.809 2.524
H 691.3864 120 142.176 1.193
H 691.3878 120 137.033 1.349
H 691.3893 120 134.408 1.751
H 691.3913 120 140.355 5.166
H 691.3928 120 135.527 1.766
H 691.3943 120 141.914 1.849
H 691.3964 120 135.153 1.761
H 691.3977 120 136.781 0.972
H 691.3999 120 126.948 0.980
H 692.3336 120 119.022 2.366
H 692.3351 120 118.366 2.780
H 692.3366 120 118.803 2.361
H 692.3387 120 122.469 3.639
H 692.3402 120 128.952 2.681
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 19
H 692.3417 120 118.257 2.777
H 692.3439 120 120.455 2.343
H 692.3453 120 118.584 3.864
H 692.3468 120 118.803 2.311
H 692.3489 120 120.012 2.641
H 692.3503 120 121.011 3.349
H 692.3518 120 118.693 2.726
H 692.3539 120 116.634 3.385
H 692.3553 120 119.792 2.751
H 692.3569 120 119.681 2.690
H 692.3590 120 117.714 3.835
H 692.3605 120 119.241 2.370
H 692.3619 120 118.584 2.916
H 692.3717 120 124.631 2.448
H 692.3729 120 121.346 3.439
H 692.3743 120 118.912 2.517
H 692.3759 120 119.131 2.400
H 692.3778 120 119.681 2.943
H 692.3793 120 119.681 3.392
H 692.3807 120 117.065 2.327
H 692.3828 120 120.566 2.507
H 692.3843 120 117.714 2.371
H 692.3857 120 119.022 2.366
H 692.3878 120 117.822 2.315
H 692.3907 120 120.234 2.459
H 692.3922 120 120.677 2.348
H 692.3937 120 120.900 2.839
H 692.3959 120 118.257 3.352
H 692.3973 120 121.235 2.847
H 692.3988 120 120.789 2.433
H 692.4003 120 122.582 2.595
H 692.4017 120 121.458 2.525
H 692.4032 120 119.131 2.340
H 692.4053 120 122.582 2.385
H 692.4067 120 120.900 2.403
H 692.4082 120 119.681 2.811
H 692.4103 120 122.356 2.432
H 692.4118 120 119.461 3.467
H 692.4133 120 121.235 2.668
H 692.4155 120 121.346 2.384
H 692.4169 120 123.716 2.407
H 692.4184 120 118.148 2.298
H 692.4500 120 118.803 2.790
H 692.4514 120 123.148 2.419
H 692.4551 120 120.789 2.715
H 692.4565 120 119.461 2.374
H 692.4580 120 116.527 2.423
H 692.4602 120 122.469 2.876
H 692.4616 120 121.011 2.377
H 693.3339 120 124.631 1.014
H 693.3353 120 124.516 1.364
H 693.3368 120 123.261 1.618
H 693.3389 120 123.602 1.440
H 693.3403 120 124.516 1.451
H 693.3417 120 121.794 1.692
H 693.3438 120 121.011 1.410
H 693.3453 120 120.123 1.093
H 693.3467 120 121.570 0.989
20 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 693.3489 120 124.173 1.130
H 693.3503 120 122.695 1.117
H 693.3519 120 121.123 1.102
H 693.3541 120 119.351 1.025
H 693.3556 120 122.131 1.111
H 693.3571 120 123.261 1.122
H 693.3593 120 121.458 1.503
H 693.3607 120 129.189 2.209
H 693.3622 120 122.695 1.263
H 693.3643 120 123.488 1.195
H 693.3658 120 122.244 1.112
H 693.3673 120 120.455 1.096
H 693.3694 120 122.131 1.792
H 693.3708 120 120.234 1.032
H 693.3723 120 122.131 0.994
H 693.3745 120 123.261 1.712
H 693.3760 120 121.570 1.176
H 693.3774 120 121.682 1.882
H 693.3795 120 121.906 1.984
H 693.3798 120 123.261 4.246
H 693.3813 120 121.458 2.901
H 693.3834 120 125.091 1.288
H 693.3849 120 120.566 1.035
H 693.3878 120 124.516 1.133
H 693.3892 120 125.784 2.151
H 693.3907 120 122.808 1.520
H 693.3927 120 125.322 1.373
H 693.3942 120 124.861 1.368
H 693.3959 120 125.206 1.139
H 693.3977 120 126.831 2.486
H 693.3992 120 126.132 1.220
H 693.4006 120 130.625 3.120
H 693.4022 120 127.182 3.482
H 693.4037 120 125.669 2.463
H 693.4052 120 124.746 1.071
H 693.4073 120 124.287 2.861
H 693.4088 120 125.553 1.143
H 693.4091 120 125.669 4.777
H 693.4126 120 125.437 3.655
H 693.4141 120 126.598 3.466
H 693.4155 120 127.652 1.873
H 693.4176 120 124.631 1.636
H 693.4191 120 126.016 1.654
H 693.4205 120 124.631 1.928
H 693.4226 120 125.322 2.040
H 693.4241 120 124.746 2.340
H 693.4256 120 125.322 4.429
H 693.4276 120 126.248 5.251
H 693.4291 120 128.714 4.663
H 693.4305 120 128.359 6.955
H 693.4327 120 127.887 7.968
H 693.4342 120 129.070 2.860
H 693.4357 120 132.077 6.561
H 693.4377 120 126.016 6.373
H 693.4392 120 129.786 6.214
H 693.4407 120 126.948 7.566
H 693.4421 120 126.714 6.067
H 693.4436 120 130.986 8.754
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 21
H 693.4451 120 129.427 5.964
H 693.4471 120 124.746 9.127
H 693.4487 120 122.582 1.115
H 693.4501 120 124.287 1.067
H 693.4522 120 121.458 1.782
H 693.4537 120 120.455 1.165
H 693.4551 120 123.148 1.616
H 694.3585 120 126.598 1.567
H 694.3599 120 130.866 1.659
H 694.3615 120 125.784 1.557
H 694.3604 120 123.944 1.921
H 694.3649 120 126.248 1.563
H 694.3665 120 127.299 1.900
H 694.3685 120 123.944 1.921
H 694.3700 120 128.714 1.677
H 694.3715 120 128.241 1.587
H 694.3735 120 127.417 1.902
H 694.3750 120 129.666 5.188
H 694.3765 120 128.241 1.845
H 694.3785 120 129.905 2.530
H 694.3800 120 130.505 2.183
H 694.3815 120 129.382 1.639
H 694.3834 120 130.025 3.869
H 694.3849 120 129.308 4.726
H 694.3864 120 129.905 3.331
H 694.3884 120 129.308 3.316
H 694.3899 120 128.477 2.888
H 694.3913 120 127.769 1.581
H 694.3934 120 127.534 1.579
H 694.3948 120 130.625 3.140
H 694.3964 120 130.145 2.925
H 694.3983 120 130.265 1.697
H 694.3998 120 130.025 2.439
H 694.4013 120 130.986 1.707
H 694.4034 120 129.308 4.726
H 694.4049 120 131.349 2.654
H 694.4064 120 131.228 1.663
H 694.4078 120 131.955 2.764
H 694.4093 120 130.866 1.659
H 694.4108 120 126.714 1.606
H 694.4129 120 131.470 2.286
H 694.4144 120 128.833 1.633
H 694.4159 120 128.714 1.677
H 694.4175 120 131.228 2.113
H 694.4189 120 130.625 1.656
H 694.4204 120 132.809 1.683
H 694.4219 120 131.834 1.671
H 694.4233 120 132.931 1.984
H 694.4248 120 136.781 1.734
H 694.4270 120 136.153 2.554
H 694.4291 120 138.174 4.931
H 694.4307 120 133.914 3.762
H 694.4321 120 131.349 1.626
H 694.4341 120 134.532 1.705
H 694.4355 120 130.745 2.187
H 694.4370 120 132.564 1.727
H 694.4385 120 132.320 2.130
H 694.4399 120 132.564 2.878
22 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 694.4414 120 130.625 1.879
H 694.4435 120 130.265 1.809
H 694.4450 120 132.931 1.685
H 694.4465 120 132.564 3.083
H 694.4479 120 132.320 3.393
H 694.4495 120 133.176 2.498
H 694.4509 120 137.286 1.789
H 694.4529 120 133.299 1.650
H 694.4544 120 137.920 2.686
H 694.4559 120 135.527 4.146
H 695.3516 120 126.481 0.737
H 695.3531 120 128.241 1.476
H 695.3546 120 128.005 0.939
H 695.3566 120 126.365 1.029
H 695.3580 120 126.481 0.737
H 695.3596 120 124.631 0.642
H 695.3616 120 124.631 2.313
H 695.3630 120 126.132 0.735
H 695.3645 120 127.887 1.694
H 695.3667 120 129.786 0.952
H 695.3682 120 125.553 0.824
H 695.3696 120 126.714 0.738
H 695.3711 120 124.746 0.819
H 695.3726 120 128.952 1.156
H 695.3740 120 130.265 1.277
H 695.3765 120 129.427 0.754
H 695.3779 120 126.714 1.242
H 695.3794 120 129.666 1.493
H 695.3815 120 124.631 0.642
H 695.3829 120 124.402 1.115
H 695.3844 120 125.669 1.775
H 695.3857 120 125.437 1.229
H 695.3879 120 132.564 1.990
H 695.3894 120 128.359 0.842
H 695.3915 120 128.596 1.817
H 695.3929 120 126.481 0.737
H 695.3944 120 123.602 0.811
H 695.3965 120 125.322 0.645
H 695.3979 120 129.189 1.939
H 695.3994 120 130.745 0.673
H 695.4015 120 124.746 0.915
H 695.4030 120 128.596 1.260
H 695.4044 120 128.005 1.696
H 695.4065 120 123.716 0.637
H 695.4080 120 129.905 1.835
H 695.4095 120 126.365 0.927
H 696.3481 120 129.070 1.375
H 696.3496 120 126.016 1.437
H 695.1936 120 129.547 1.477
H 696.3533 120 129.189 1.748
H 696.3547 120 131.955 1.505
H 696.3562 120 132.442 1.510
H 696.3583 120 128.833 1.417
H 696.3597 120 130.625 1.436
H 696.3612 120 132.564 1.877
H 696.3633 120 131.470 1.861
H 696.3647 120 133.791 1.587
H 696.3662 120 129.308 1.831
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 23
H 696.3677 120 128.596 1.820
H 696.3698 120 126.598 1.444
H 696.3713 120 127.652 1.404
H 696.3727 120 128.714 1.665
H 696.3749 120 131.470 1.499
H 696.3763 120 128.477 1.738
H 696.3778 120 130.745 1.438
H 696.3815 120 130.986 2.217
H 696.3829 120 130.745 1.691
H 696.3844 120 131.228 2.319
H 696.3865 120 129.905 2.013
H 696.3879 120 133.054 2.351
H 696.3894 120 130.986 1.554
H 696.3915 120 130.505 1.765
H 696.3930 120 130.265 1.612
H 696.3945 120 134.038 1.897
H 696.3966 120 132.199 2.142
H 696.3981 120 132.564 1.641
H 696.3995 120 131.107 1.556
H 696.4016 120 130.986 2.030
H 696.4031 120 130.986 3.365
H 696.4053 120 131.712 7.665
H 696.4073 120 131.712 1.502
H 696.4088 120 131.107 2.935
H 699.3295 120 124.976 1.120
H 699.3309 120 127.887 1.259
H 699.3325 120 124.402 1.225
H 699.3345 120 124.058 1.785
H 699.3360 120 121.011 1.256
H 699.3375 120 122.356 1.761
H 699.3396 120 123.716 1.159
H 699.3411 120 125.437 1.175
H 699.3426 120 123.944 2.071
H 699.3454 120 123.944 3.210
H 699.3469 120 123.944 1.358
H 699.3484 120 123.944 1.161
H 699.3505 120 120.123 2.904
H 699.3521 120 123.716 1.433
H 699.3535 120 123.148 1.426
H 699.3555 120 122.131 1.850
H 699.3569 120 122.244 1.145
H 699.3584 120 123.944 2.474
H 699.3605 120 124.631 3.879
H 699.3619 120 125.091 1.707
H 699.3634 120 125.437 1.536
H 699.3654 120 122.921 1.862
H 699.3669 120 123.148 2.872
H 699.3683 120 121.458 1.089
H 699.4052 120 126.831 1.137
H 699.3718 120 121.123 1.192
H 699.3734 120 123.602 1.217
H 699.3754 120 127.299 1.474
H 699.3768 120 127.652 2.654
H 699.3784 120 130.265 1.282
H 699.3821 120 126.481 1.465
H 699.3835 120 128.833 1.207
H 699.3850 120 126.948 3.288
H 699.3871 120 126.831 1.248
24 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 699.3885 120 129.666 3.247
H 699.3900 120 130.866 3.389
H 699.3922 120 126.831 3.176
H 699.3936 120 125.437 1.997
H 699.3950 120 125.091 1.371
H 699.3971 120 123.716 1.356
H 699.3986 120 122.356 1.146
H 699.4000 120 123.830 1.110
H 699.4023 120 126.948 1.250
H 699.4038 120 122.469 1.147
H 699.4052 120 124.402 1.225
H 699.4073 120 126.481 5.734
H 699.4088 120 124.287 1.978
H 699.4103 120 125.322 1.534
H 699.4123 120 124.402 1.441
H 699.4138 120 122.921 1.769
H 699.4153 120 125.784 1.378
H 699.4173 120 125.437 2.196
H 699.4188 120 124.516 1.524
H 699.4202 120 123.034 1.425
H 699.4224 120 123.944 1.220
H 699.4238 120 122.808 1.274
H 699.4253 120 121.906 1.492
H 700.3828 120 124.059 1.010
H 700.3843 120 123.944 1.128
H 700.3857 120 125.553 1.215
H 700.3879 120 124.402 1.068
H 700.3893 120 122.131 1.111
H 700.3908 120 129.427 1.053
H 700.3929 120 126.715 1.088
H 700.3943 120 126.831 1.306
H 700.3958 120 122.356 1.113
H 700.3978 120 127.534 1.579
H 700.3994 120 127.065 1.156
H 700.4009 120 125.206 1.643
H 700.4030 120 125.553 1.376
H 700.4044 120 128.952 1.413
H 700.4059 120 124.516 1.926
H 700.4079 120 125.669 1.144
H 700.4091 120 126.365 1.385
H 700.4108 120 125.553 1.078
H 700.4129 120 126.249 1.221
H 700.4143 120 125.206 1.019
H 700.4158 120 124.976 1.287
H 700.4178 120 124.631 1.206
H 700.4193 120 126.365 2.371
H 700.4208 120 124.402 1.633
H 700.4244 120 127.652 1.096
H 700.4259 120 127.065 1.392
H 700.4274 120 126.132 1.027
H 700.4288 120 126.249 1.149
H 700.4291 120 125.206 2.141
H 700.4305 120 130.745 2.344
H 700.4326 120 127.417 3.488
H 700.4341 120 126.831 2.273
H 700.4355 120 123.944 1.627
H 700.4376 120 124.861 3.200
H 700.4391 120 124.516 1.827
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 25
H 700.4406 120 127.887 1.401
H 700.4420 120 126.715 1.859
H 700.4435 120 123.602 1.530
H 700.4449 120 127.769 1.489
H 700.4464 120 124.173 1.130
H 700.4479 120 123.602 1.354
H 700.4499 120 122.695 1.430
H 700.4514 120 123.375 1.059
H 700.4529 120 125.553 1.744
H 700.4549 120 124.516 1.069
H 700.4448 120 123.830 1.357
H 700.4463 120 123.375 1.352
H 700.4598 120 123.716 1.062
H 700.4614 120 126.948 1.228
H 700.4628 120 120.012 1.236
H 700.4642 120 122.469 1.261
H 701.3506 120 117.281 1.487
H 701.3521 120 117.389 1.752
H 701.3535 120 120.012 1.521
H 701.3558 120 122.244 2.293
H 701.3572 120 117.497 1.632
H 701.3588 120 116.312 1.674
H 701.3608 120 117.605 1.692
H 701.3622 120 118.912 1.652
H 701.3637 120 116.098 1.733
H 701.3658 120 113.143 1.434
H 701.3672 120 113.770 1.978
H 701.3688 120 114.611 1.917
H 701.3708 120 113.247 1.823
H 701.3724 120 112.209 1.422
H 701.3738 120 110.364 1.777
H 701.3759 120 112.002 1.874
H 701.3774 120 116.420 1.476
H 701.3789 120 115.671 1.664
H 701.3810 120 116.205 1.734
H 701.3824 120 117.065 1.747
H 701.3839 120 119.131 1.601
H 701.3862 120 118.475 1.768
H 701.3876 120 115.671 1.664
H 701.3890 120 111.078 1.931
H 701.3911 120 116.527 1.677
H 701.3926 120 117.281 1.687
H 701.3940 120 115.778 1.728
H 701.3962 120 115.671 1.507
H 701.3977 120 118.803 2.065
H 701.3996 120 117.931 1.697
H 701.4011 120 117.281 1.687
H 701.4026 120 118.693 1.546
H 701.4045 120 119.131 1.714
H 701.4060 120 117.497 1.579
H 701.4075 120 119.351 1.555
H 701.4095 120 118.693 1.772
H 701.4110 120 119.131 1.714
H 701.4125 120 116.742 1.445
H 701.4147 120 115.991 1.511
H 701.4162 120 116.957 2.033
H 701.4177 120 116.742 1.809
H 701.4199 120 116.420 1.517
26 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 701.4214 120 117.713 1.694
H 701.4229 120 114.189 1.447
H 702.3953 120 124.173 1.680
H 702.3967 120 123.602 1.814
H 702.3982 120 123.716 2.229
H 702.4003 120 125.784 1.743
H 702.4017 120 125.437 1.739
H 702.4032 120 121.235 1.640
H 702.4053 120 125.091 1.782
H 702.4067 120 124.746 2.679
H 702.4082 120 123.602 1.814
H 702.4103 120 122.695 1.701
H 702.4117 120 125.900 1.703
H 702.4132 120 125.437 2.181
H 702.4152 120 124.631 1.651
H 702.4174 120 122.356 1.621
H 702.4194 120 124.059 2.157
H 702.4214 120 122.582 1.799
H 702.4224 120 124.631 1.686
H 702.4244 120 124.976 1.732
H 702.4259 120 122.244 2.051
H 702.4274 120 125.437 1.662
H 702.4294 120 125.437 1.900
H 702.4309 120 123.148 1.928
H 702.4324 120 124.402 2.087
H 702.4344 120 123.716 1.674
H 702.4359 120 125.206 1.735
H 702.4374 120 124.631 1.888
H 702.4393 120 124.631 1.727
H 702.4408 120 123.944 1.819
H 702.4423 120 123.830 1.875
H 702.4443 120 123.375 1.669
H 702.4458 120 124.861 2.095
H 702.4473 120 123.148 2.066
H 702.4493 120 126.249 1.750
H 702.4508 120 123.602 1.672
H 702.4523 120 124.173 1.680
H 702.4537 120 122.808 1.802
H 703.4019 120 116.957 1.096
H 703.4033 120 114.295 1.478
H 703.4048 120 115.885 1.086
H 703.4062 120 113.979 1.068
H 703.4077 120 113.770 1.066
H 703.4092 120 118.039 1.106
H 703.4113 120 115.671 1.200
H 703.4128 120 112.727 1.056
H 703.4142 120 113.979 1.068
H 703.4163 120 112.416 1.166
H 703.4177 120 116.849 1.681
H 703.4192 120 118.257 1.448
H 703.4213 120 115.034 1.078
H 703.4228 120 112.209 1.104
H 703.4242 120 116.098 1.205
H 703.4263 120 117.497 1.288
H 703.4277 120 115.034 1.078
H 703.4298 120 116.312 1.145
H 703.4313 120 116.312 1.090
H 703.4340 120 113.874 1.067
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 27
H 703.4354 120 118.475 1.450
H 703.4370 120 115.992 2.706
H 703.4390 120 115.459 1.136
H 703.4405 120 118.257 1.370
H 703.4420 120 112.727 1.056
H 668.7222 120 114.190 1.070
H 703.4456 120 114.928 1.077
H 703.4470 120 116.527 1.427
H 703.4485 120 114.084 1.184
H 703.5240 120 114.822 1.852
H 703.5255 120 118.475 2.026
H 703.5270 120 116.205 2.329
H 703.5284 120 116.098 1.872
H 703.5300 120 117.173 2.051
H 703.5314 120 115.459 2.072
H 703.5334 120 118.475 1.910
H 703.5349 120 116.420 2.205
H 703.5364 120 115.459 1.862
H 703.5385 120 116.205 1.874
H 703.5399 120 115.991 1.870
H 703.5414 120 117.713 2.501
H 703.5428 120 114.611 1.960
H 703.5443 120 115.885 1.901
H 703.5458 120 118.366 2.072
H 703.5479 120 116.098 1.942
H 703.5493 120 114.822 2.010
H 703.5508 120 116.742 2.789
H 703.5529 120 116.849 1.884
H 703.5543 120 117.713 1.898
H 703.5558 120 118.584 1.984
H 703.5583 120 114.084 1.951
H 703.5598 120 116.849 2.097
H 703.5613 120 115.778 2.192
H 703.5634 120 113.979 2.158
H 703.5648 120 117.389 2.223
H 703.5663 120 117.605 2.167
H 703.5684 120 116.634 2.628
H 703.5698 120 116.312 1.989
H 703.5713 120 117.281 1.891
H 709.5557 120 114.505 2.709
H 709.5571 120 113.665 2.793
H 710.5570 120 118.148 0.925
H 710.5585 120 118.912 1.503
H 710.5613 120 118.366 1.315
H 710.5627 120 119.241 1.000
H 710.5643 120 118.039 1.876
H 710.5663 120 116.742 2.758
H 710.5673 120 117.930 1.973
H 710.5693 120 118.693 0.929
H 720.5547 120 118.584 2.774
H 720.5562 120 116.312 3.596
H 720.5577 120 120.344 3.037
H 720.5592 120 119.791 2.861
H 720.5607 120 123.716 3.172
H 720.5621 120 121.458 2.842
H 720.5636 120 121.794 4.078
H 720.5651 120 115.459 3.119
H 720.5666 120 119.791 3.423
28 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
H 721.5507 120 131.955 3.061
H 721.5521 120 125.206 3.027
H 721.5535 120 125.322 3.448
H 721.5557 120 131.591 3.109
H 721.5571 120 132.442 3.342
H 721.5585 120 130.385 3.655
H 721.5607 120 127.299 3.041
H 721.5621 120 128.005 2.970
H 721.5636 120 129.547 3.132
H 722.5481 120 123.261 8.973
H 722.5496 120 117.605 11.772
H 722.5510 120 127.065 9.366
J 633.4851 120 60.078 5.054
J 633.4935 120 59.637 5.078
J 633.5005 120 57.374 4.908
J 633.5074 120 61.026 5.165
J 633.5208 120 59.637 5.047
J 635.5070 120 57.163 1.229
J 635.6336 120 56.483 1.373
J 635.6411 120 56.691 0.912
J 635.6470 120 58.495 1.927
J 635.6531 120 56.223 0.904
J 635.6575 120 58.065 1.328
J 635.6643 120 56.743 1.339
J 635.6752 120 57.163 1.519
J 639.6642 120 55.657 1.692
J 639.6657 120 55.172 1.728
I 504.27 60 23.344 0.637
I 504.27 60 22.294 0.406
I 504.27 60 23.130 0.210
I 508.27 60 21.095 0.384
I 508.27 60 21.487 0.391
I 508.28 60 21.487 0.391
I 509.29 60 19.239 0.175
I 509.29 60 19.063 0.173
I 509.29 60 19.063 0.173
I 511.25 60 20.332 0.185
I 511.26 60 20.332 0.185
I 511.26 60 20.710 0.188
I 511.28 60 20.520 0.187
I 511.28 60 20.332 0.185
I 511.28 60 20.520 0.187
I 516.25 60 23.560 0.214
I 516.25 60 23.344 0.212
I 516.25 60 23.344 0.425
I 516.25 60 23.778 0.216
I 516.25 60 23.998 0.437
I 516.31 60 21.095 0.384
I 516.31 60 20.902 0.380
I 516.31 60 20.710 0.377
I 517.24 60 21.290 0.194
I 517.24 60 21.095 0.192
I 517.24 60 21.095 0.192
I 619.21 30 23.344 0.425
I 619.21 30 23.130 0.421
I 619.21 30 23.344 0.425
I 619.21 30 23.344 0.425
I 619.22 30 23.778 0.433
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 29
I 619.22 30 23.344 0.425
I 619.22 30 23.560 0.429
I 619.22 30 23.344 0.425
I 619.23 30 25.362 0.231
I 619.23 30 25.362 0.231
I 619.24 30 25.362 0.231
I 619.24 30 25.362 0.231
I 619.24 30 25.129 0.229
I 619.24 30 25.362 0.231
I 619.25 30 25.129 0.229
I 619.25 30 25.362 0.231
I 619.25 30 25.362 0.231
I 619.26 30 25.362 0.231
I 631.13 30 24.220 0.441
I 631.13 30 23.778 0.433
I 631.13 30 23.998 0.437
I 631.13 30 25.362 0.462
I 632.98 30 30.774 0.280
I 632.98 30 30.774 0.280
I 632.99 30 31.346 0.285
I 632.99 30 31.929 0.291
I 632.99 30 33.127 1.206
I 632.99 30 33.434 0.304
I 633 30 30.492 0.555
I 633 30 30.492 0.555
I 633 30 29.661 0.540
I 633 30 29.661 0.540
I 633.01 30 28.852 0.263
I 633.01 30 28.852 0.525
I 633.01 30 28.066 0.255
I 633.01 30 28.066 0.511
I 633.02 30 27.554 0.501
I 633.02 30 27.051 0.492
I 633.03 30 27.554 0.501
I 633.03 30 27.301 0.248
I 634.98 30 26.314 0.479
I 634.99 30 25.362 0.462
I 634.99 30 25.129 0.457
I 634.99 30 25.129 0.457
I 635.1 30 31.929 0.581
I 635.1 30 33.743 0.614
I 635.12 30 25.597 0.932
I 635.12 30 25.833 0.940
I 635.13 30 25.597 0.699
I 635.13 30 26.314 0.718
I 635.14 30 28.326 0.516
I 635.15 30 28.066 0.511
I 635.15 30 28.326 0.516
I 635.16 30 28.588 0.520
I 635.16 30 29.119 0.530
I 635.17 30 29.119 0.795
I 635.17 30 28.852 0.525
I 635.17 30 28.852 0.525
I 635.17 30 28.066 0.511
I 635.18 30 29.119 0.795
I 635.18 30 29.389 0.535
I 635.18 30 29.119 0.530
I 635.19 30 28.852 2.100
30 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
I 640.22 120 29.119 0.265
I 640.22 120 29.119 0.265
I 641.11 120 29.389 0.535
I 641.11 120 28.852 0.525
I 643.21 120 30.774 0.280
I 643.22 120 30.774 0.280
I 644.1 120 31.346 0.285
I 644.1 120 31.346 0.285
I 648.2 120 32.224 0.586
I 648.21 120 32.522 0.592
I 648.22 120 32.224 0.586
I 655.03 120 32.224 1.759
I 655.03 120 32.224 0.586
I 655.2 120 31.929 0.581
I 655.03 120 28.066 0.255
I 655.03 120 27.809 0.253
I 655.2 120 34.370 0.313
I 655.2 120 34.370 0.313
I 655.21 120 35.009 0.319
I 655.21 120 35.009 0.319
I 655.22 120 34.688 0.316
I 655.22 120 35.009 0.319
I 678.03 120 39.827 0.626
I 678.03 120 39.608 0.639
I 678.04 120 39.974 0.645
I 678.04 120 39.718 0.713
I 678.06 120 38.885 0.618
I 678.06 120 39.608 0.794
I 678.07 120 39.173 0.615
I 678.07 120 39.901 0.655
I 678.09 120 39.245 0.657
I 678.09 120 39.245 0.624
I 678.1 120 39.644 0.639
I 678.12 120 38.387 0.610
I 678.12 120 38.529 0.612
I 678.13 120 38.422 0.630
I 678.13 120 38.493 0.612
I 679.08 120 37.756 1.039
I 679.09 120 38.778 0.848
I 680.01 120 39.974 0.635
I 680.02 120 38.000 0.665
I 680.03 120 37.410 0.671
I 680.03 120 37.375 0.639
I 680.04 120 36.896 0.595
I 680.05 120 37.617 0.629
I 680.06 120 37.169 0.599
I 680.06 120 38.035 0.613
I 680.08 120 37.410 0.655
I 680.08 120 37.272 0.815
I 680.14 120 35.726 0.568
I 680.14 120 35.924 0.564
I 681.1 120 38.458 0.643
I 681.1 120 38.210 0.607
I 681.11 120 38.529 0.612
I 681.12 120 36.457 0.579
I 681.13 120 39.245 0.937
I 681.13 120 39.901 0.716
I 682.03 120 38.000 0.604
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 31
I 682.03 120 37.860 0.602
I 682.04 120 37.169 0.591
I 682.05 120 36.896 0.586
I 682.06 120 36.491 0.580
I 682.06 120 36.357 0.596
I 682.07 120 36.457 0.672
I 682.08 120 36.794 0.616
I 682.1 120 36.457 0.731
I 682.1 120 36.189 0.605
I 682.11 120 36.223 0.747
I 682.11 120 36.693 0.851
I 682.13 120 35.660 0.610
I 682.13 120 36.090 0.767
I 683.02 120 38.210 0.788
I 683.02 120 37.169 0.599
I 683.02 120 36.223 0.584
I 683.03 120 36.457 0.588
I 683.03 120 35.594 0.574
I 683.05 120 35.431 0.593
I 683.05 120 35.792 0.577
I 683.06 120 35.924 0.579
I 683.06 120 38.849 0.680
I 684.02 120 38.885 0.802
I 684.02 120 39.390 0.626
I 684.04 120 39.608 0.771
I 684.04 120 38.529 0.605
I 684.05 120 37.479 0.604
I 684.05 120 39.101 0.631
I 684.07 120 39.029 0.719
I 684.07 120 36.189 0.633
I 689.02 120 36.761 0.603
I 689.02 120 36.896 0.662
I 689.03 120 35.957 0.645
I 689.04 120 41.132 0.663
I 690.08 120 40.718 0.647
I 690.08 120 42.285 0.759
I 690.09 120 42.052 0.704
I 690.11 120 42.480 0.851
I 690.11 120 41.589 0.696
I 690.11 120 42.794 1.022
I 691.06 120 41.704 0.655
I 691.06 120 42.013 0.718
I 691.08 120 42.207 0.951
I 691.08 120 38.387 0.619
I 692.02 120 38.105 0.684
I 692.02 120 39.426 0.660
I 692.04 120 39.101 0.669
I 692.04 120 37.825 0.601
I 692.06 120 38.210 0.639
I 692.08 120 38.778 0.616
I 692.08 120 38.885 0.611
I 692.14 120 39.827 0.734
I 693.02 120 39.608 0.629
I 693.03 120 39.499 0.709
I 693.04 120 38.849 0.680
I 693.04 120 38.458 0.643
I 693.05 120 38.316 0.609
I 693.06 120 39.426 0.747
32 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
I 693.07 120 39.029 0.700
I 693.08 120 38.635 0.634
I 693.09 120 37.548 0.775
I 693.09 120 37.965 0.603
I 693.1 120 37.686 0.592
I 693.11 120 37.756 0.600
I 693.12 120 37.930 0.596
I 693.12 120 38.387 0.610
I 693.14 120 37.513 0.596
I 694.05 120 38.210 0.600
I 694.05 120 38.493 0.612
I 694.08 120 38.493 0.612
I 694.08 120 39.462 0.627
I 694.09 120 39.974 0.635
I 694.1 120 40.011 0.636
I 694.11 120 39.499 0.769
I 694.11 120 40.868 0.649
I 694.11 120 40.568 0.679
I 694.13 120 39.499 0.675
I 694.13 120 39.390 0.689
I 694.14 120 39.353 0.635
I 694.14 120 39.101 0.614
I 695.05 120 40.680 0.639
I 695.05 120 39.938 0.635
I 695.06 120 38.921 0.628
I 695.07 120 38.671 1.275
I 695.08 120 38.635 0.614
I 695.08 120 38.458 0.611
I 695.09 120 39.137 0.685
I 695.1 120 38.422 0.604
I 696.05 120 39.101 0.621
I 696.05 120 39.245 0.704
I 696.06 120 40.531 0.693
I 696.06 120 40.196 0.639
I 696.08 120 40.643 0.646
I 696.08 120 40.755 0.794
I 696.09 120 40.943 0.660
I 699.03 120 41.475 0.785
I 699.03 120 41.436 0.651
I 699.04 120 40.906 0.650
I 699.04 120 41.436 0.693
I 699.04 120 41.551 0.787
I 699.06 120 42.052 0.796
I 699.06 120 41.132 0.675
I 699.08 120 41.360 0.667
I 699.08 120 41.666 0.729
I 699.09 120 40.755 0.648
I 699.1 120 41.589 0.653
I 699.11 120 40.943 0.651
I 699.11 120 41.936 0.666
I 700.04 120 41.284 0.723
I 700.04 120 41.170 0.849
I 700.05 120 46.388 0.107
I 700.05 120 40.793 0.714
I 700.05 120 40.793 0.641
I 700.08 120 41.246 0.648
I 700.08 120 40.943 0.651
I 700.09 120 40.755 0.713
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 33
I 700.1 120 40.270 0.742
I 700.11 120 40.755 0.713
I 700.11 120 40.680 0.647
I 701.03 120 40.943 0.735
I 701.03 120 37.895 0.648
I 701.04 120 37.721 0.695
I 701.05 120 38.387 0.610
I 701.06 120 38.387 0.619
I 701.06 120 38.778 0.874
I 701.07 120 39.137 0.702
I 701.07 120 37.479 0.615
I 701.07 120 37.895 0.648
I 701.09 120 37.101 0.590
I 701.09 120 37.238 0.592
I 702.04 120 39.499 0.691
I 702.04 120 40.307 0.763
I 702.05 120 40.382 0.634
I 702.05 120 40.270 0.633
I 702.07 120 41.094 0.653
I 702.07 120 40.568 0.645
I 702.08 120 41.132 0.654
I 702.08 120 41.513 0.669
I 703.05 120 36.592 0.657
I 703.06 120 37.341 0.593
I 703.06 120 37.375 0.613
I 703.08 120 36.964 0.647
I 703.08 120 37.341 0.638
I 704.04 120 36.390 0.622
I 704.04 120 36.056 0.581
I 704.06 120 36.998 0.597
I 704.06 120 36.625 0.575
I 704.08 120 36.896 0.586
I 704.08 120 37.721 0.599
I 711.07 120 36.524 0.574
I 711.08 120 36.090 0.592
I 715.04 120 37.032 0.633
I 715.04 120 36.794 0.616
I 715.05 120 36.964 0.596
I 715.05 120 36.727 0.643
I 721.06 120 34.212 0.585
I 721.06 120 35.236 0.560
I 722.06 120 37.965 0.783
I 722.06 120 38.281 0.705
R 504.27 60 20.601 0.375
R 504.28 60 19.856 0.361
R 504.28 60 20.791 0.757
R 508.28 60 17.942 0.163
R 508.28 60 17.778 0.162
R 508.29 60 17.778 0.162
R 509.29 60 17.778 0.162
R 509.29 60 17.615 0.160
R 509.29 60 17.778 0.162
R 510.3 60 16.214 0.295
R 510.3 60 16.364 0.149
R 510.3 60 16.364 0.149
R 511.26 60 18.962 0.173
R 511.26 60 18.788 0.171
R 511.26 60 19.137 0.174
34 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
R 511.28 60 18.962 0.173
R 511.28 60 18.788 0.171
R 511.28 60 18.788 0.171
R 516.25 60 21.178 0.193
R 516.25 60 18.445 0.168
R 516.25 60 18.616 0.169
R 517.24 60 19.674 0.179
R 517.24 60 19.314 0.176
R 517.24 60 19.493 0.177
R 517.25 60 19.493 0.177
R 517.25 60 19.493 0.177
R 517.25 60 19.493 0.177
R 619.2 30 26.175 0.476
R 619.21 30 26.175 0.476
R 619.21 30 26.175 0.476
R 619.21 30 26.175 0.476
R 619.22 30 23.653 0.215
R 619.22 30 23.653 0.215
R 619.23 30 23.872 0.217
R 619.23 30 23.872 0.217
R 619.24 30 23.653 0.215
R 619.24 30 23.872 0.217
R 619.24 30 23.653 0.215
R 619.24 30 23.872 0.217
R 619.25 30 24.093 0.219
R 619.25 30 24.093 0.219
R 619.25 30 24.093 0.219
R 619.25 30 24.093 0.219
R 631.13 30 26.661 0.485
R 631.13 30 26.908 0.490
R 632.98 30 28.700 0.261
R 632.98 30 28.700 0.261
R 632.99 30 28.966 0.264
R 632.99 30 28.700 0.261
R 632.99 30 28.966 0.264
R 632.99 30 28.966 0.264
R 632.99 30 29.234 0.266
R 632.99 30 29.234 0.266
R 633 30 28.700 0.261
R 633 30 28.700 0.261
R 633.01 30 27.918 0.254
R 633.01 30 28.176 0.256
R 633.01 30 27.662 0.252
R 633.01 30 27.408 0.249
R 633.02 30 26.661 0.243
R 633.02 30 26.661 0.243
R 633.02 30 26.417 0.240
R 633.02 30 26.417 0.240
R 634.98 30 23.653 0.215
R 634.98 30 23.008 0.209
R 634.98 30 23.872 0.217
R 634.98 30 23.872 0.217
R 635.1 30 27.408 0.249
R 635.1 30 27.408 0.249
R 635.13 30 28.176 0.769
R 635.13 30 28.966 0.527
R 635.13 30 28.437 1.035
R 635.13 30 28.437 0.776
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 35
R 635.14 30 29.777 0.813
R 635.14 30 28.700 0.784
R 635.15 30 28.176 0.769
R 635.15 30 28.700 0.784
R 635.15 30 26.175 0.238
R 635.15 30 25.697 0.468
R 635.16 30 25.935 0.236
R 635.16 30 25.935 0.236
R 635.17 30 24.093 0.658
R 635.17 30 25.935 0.236
R 635.17 30 25.935 0.236
R 635.18 30 26.417 0.240
R 635.18 30 26.661 0.485
R 635.18 30 25.697 0.468
R 635.18 30 24.997 0.455
R 635.19 30 25.935 0.472
R 635.19 30 26.417 0.481
R 640.22 120 28.966 0.264
R 640.22 120 27.408 0.249
R 641.11 120 31.760 0.578
R 641.11 120 31.760 0.578
R 644.1 120 27.408 0.499
R 644.1 120 27.662 0.503
R 648.21 120 28.437 0.259
R 648.21 120 28.966 0.264
R 648.22 120 28.437 0.518
R 648.22 120 30.053 1.641
R 652.05 120 31.760 0.289
R 655.02 120 26.417 0.240
R 655.02 120 26.417 0.240
R 655.03 120 25.461 0.232
R 655.03 120 25.461 0.232
R 655.2 120 32.351 0.294
R 655.2 120 32.351 0.294
R 655.21 120 32.351 0.294
R 655.21 120 32.351 0.294
R 665.04 30 31.469 0.573
R 665.04 30 32.054 0.583
R 678.02 30 34.824 0.634
R 678.02 120 35.480 0.915
R 678.02 120 35.980 0.927
R 678.04 120 35.980 0.957
R 678.04 120 35.409 0.914
R 678.05 120 35.303 0.925
R 678.05 120 35.409 0.922
R 678.07 120 35.303 0.919
R 678.07 120 35.551 0.920
R 678.08 120 34.846 0.989
R 678.08 120 34.846 0.908
R 678.1 120 34.846 0.904
R 678.1 120 34.637 0.909
R 678.11 120 34.222 0.893
R 678.11 120 34.119 0.891
R 678.13 120 33.406 0.869
R 678.13 120 33.676 0.876
R 679.08 120 34.187 0.958
R 679.08 120 33.880 0.891
R 680.01 120 33.507 1.134
36 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
R 680.01 120 33.507 1.248
R 680.02 120 33.138 1.062
R 680.03 120 32.707 0.857
R 680.04 120 32.972 0.869
R 680.04 120 33.238 0.933
R 680.05 120 33.005 1.185
R 680.06 120 33.005 0.970
R 680.07 120 32.707 1.318
R 680.07 120 32.905 1.159
R 680.13 120 32.707 0.896
R 680.13 120 31.731 0.862
R 681.09 120 31.699 0.845
R 681.1 120 34.360 0.892
R 681.11 120 34.498 0.900
R 681.11 120 34.291 0.960
R 681.12 120 34.429 0.929
R 681.13 120 34.671 0.917
R 682.02 120 35.021 0.934
R 682.03 120 34.846 0.939
R 682.04 120 34.846 1.176
R 682.04 120 33.744 1.023
R 682.05 120 33.272 1.046
R 682.06 120 32.806 1.156
R 682.07 120 32.905 0.874
R 682.07 120 33.812 0.889
R 682.09 120 33.744 1.120
R 682.09 120 31.539 0.997
R 682.11 120 31.476 0.847
R 682.11 120 32.021 0.890
R 682.12 120 31.317 0.862
R 682.12 120 31.190 0.832
R 683.01 120 31.444 0.832
R 683.01 120 31.190 0.858
R 683.03 120 31.635 0.831
R 683.03 120 31.476 0.828
R 683.04 120 31.731 0.853
R 683.04 120 32.086 0.842
R 683.06 120 31.731 0.834
R 683.06 120 30.782 0.816
R 684.01 120 31.001 0.821
R 684.01 120 33.339 0.936
R 684.02 120 33.305 0.884
R 684.02 120 34.085 0.896
R 684.03 120 33.541 0.877
R 684.03 120 34.050 0.919
R 684.05 120 34.602 0.997
R 684.05 120 34.256 0.915
R 684.06 120 34.050 0.919
R 684.06 120 33.812 0.879
R 689.01 120 33.744 0.882
R 689.02 120 31.892 0.837
R 689.03 120 32.183 0.844
R 689.03 120 32.054 0.870
R 690.07 120 32.444 0.851
R 690.08 120 36.161 0.953
R 690.09 120 35.056 0.935
R 690.09 120 35.909 0.934
R 690.1 120 36.125 0.934
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 37
R 690.11 120 36.269 0.998
R 691.06 120 36.415 0.946
R 691.06 120 36.891 1.216
R 691.07 120 38.277 1.190
R 691.07 120 37.410 1.027
R 692.02 120 37.112 1.137
R 692.02 120 33.914 0.886
R 692.03 120 34.256 0.915
R 692.03 120 33.272 0.883
R 692.05 120 33.406 1.032
R 692.06 120 33.138 0.867
R 692.07 120 33.272 0.871
R 692.08 120 33.071 0.866
R 692.09 120 33.948 0.887
R 692.09 120 33.575 0.878
R 692.13 120 33.507 0.916
R 692.13 120 33.914 0.927
R 693.02 120 34.567 0.902
R 693.02 120 34.222 0.893
R 693.03 120 33.710 0.881
R 693.04 120 33.238 0.870
R 693.05 120 33.812 0.883
R 693.05 120 33.642 0.879
R 693.06 120 33.105 0.867
R 693.07 120 33.205 0.869
R 693.07 120 33.205 0.869
R 693.07 120 32.905 0.862
R 693.08 120 33.005 0.864
R 693.09 120 32.608 0.855
R 693.1 120 32.938 0.863
R 693.1 120 32.872 0.861
R 693.11 120 32.839 0.860
R 693.12 120 32.740 0.858
R 694.05 120 35.729 0.929
R 694.05 120 35.409 0.922
R 694.06 120 35.587 0.926
R 694.06 120 35.622 0.927
R 694.07 120 34.916 0.910
R 694.07 120 34.811 0.907
R 694.09 120 35.232 0.917
R 694.09 120 35.551 0.931
R 694.1 120 35.515 0.924
R 695.04 120 34.637 0.903
R 695.05 120 34.741 0.906
R 695.06 120 33.880 0.881
R 695.06 120 34.085 0.890
R 695.07 120 33.744 0.888
R 695.08 120 33.778 0.883
R 695.09 120 34.187 0.892
R 695.09 120 33.914 0.886
R 696.04 120 35.338 0.974
R 696.04 120 34.986 0.907
R 696.06 120 34.532 0.901
R 696.06 120 34.567 0.902
R 696.07 120 35.056 0.913
R 696.08 120 35.126 0.915
R 696.09 120 36.016 0.931
R 696.09 120 36.089 1.021
38 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
R 699.02 120 37.186 1.180
R 699.02 120 36.927 1.217
R 699.04 120 35.444 1.217
R 699.04 120 36.744 1.146
R 699.05 120 36.089 0.933
R 699.05 120 36.488 0.991
R 699.07 120 35.837 0.932
R 699.08 120 35.658 0.923
R 699.09 120 36.233 0.941
R 699.09 120 35.622 1.040
R 699.1 120 36.089 0.933
R 699.11 120 36.415 0.989
R 700.03 120 36.161 0.940
R 700.03 120 35.837 0.932
R 700.05 120 35.409 0.922
R 700.05 120 35.480 0.923
R 700.06 120 35.338 0.920
R 700.06 120 35.303 0.919
R 700.07 120 34.846 0.908
R 700.08 120 35.021 0.912
R 700.09 120 34.222 0.893
R 700.09 120 35.091 0.914
R 700.1 120 35.056 0.909
R 700.11 120 35.303 0.919
R 701.02 120 33.440 0.875
R 701.03 120 33.473 0.871
R 701.04 120 34.085 0.890
R 701.04 120 34.016 0.997
R 701.05 120 33.676 0.932
R 701.06 120 33.812 1.008
R 701.07 120 33.778 1.024
R 701.07 120 32.972 0.914
R 701.08 120 33.473 0.871
R 701.08 120 33.105 1.143
R 702.03 120 36.306 1.076
R 702.04 120 36.488 0.947
R 702.05 120 35.622 0.927
R 702.05 120 35.694 0.928
R 702.06 120 36.016 0.936
R 702.06 120 36.125 0.934
R 702.08 120 36.634 0.965
R 702.08 120 36.670 0.958
R 703.04 120 32.313 0.910
R 703.04 120 32.411 0.855
R 703.05 120 32.608 0.917
R 703.06 120 32.641 0.895
R 703.07 120 32.510 0.852
R 703.08 120 32.575 0.854
R 704.04 120 32.021 0.879
R 704.04 120 32.248 0.846
R 704.05 120 31.795 0.831
R 704.05 120 32.313 0.886
R 704.07 120 32.740 0.878
R 704.07 120 32.248 0.866
R 711.07 120 32.641 0.976
R 711.07 120 32.248 1.138
R 715.04 120 32.806 1.178
R 715.03 120 32.608 0.959
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 39
R 715.05 120 32.674 1.048
R 715.05 120 32.707 1.030
R 721.06 120 31.412 0.943
R 721.06 120 31.763 1.513
R 722.05 120 33.071 1.682
R 722.07 120 34.986 0.912
R 723.05 120 35.021 1.626
V 504.29 60 18.243 0.332
V 504.29 60 18.928 0.172
V 504.29 60 18.076 0.164
V 504.3 60 18.243 0.166
V 504.3 60 18.243 0.166
V 504.3 60 18.076 0.164
V 508.29 60 17.910 0.163
V 508.29 60 17.910 0.163
V 508.29 60 17.910 0.163
V 509.29 60 17.583 0.160
V 509.29 60 17.422 0.159
V 509.29 60 17.583 0.160
V 510.3 60 16.185 0.295
V 510.3 60 16.185 0.147
V 510.3 60 16.185 0.147
V 511.26 60 18.412 0.168
V 511.26 60 18.412 0.168
V 511.26 60 18.412 0.168
V 511.28 60 18.412 0.168
V 511.28 60 18.582 0.169
V 511.28 60 18.412 0.168
V 516.31 60 18.412 0.168
V 516.31 60 18.754 0.171
V 516.31 60 18.076 0.164
V 517.24 60 18.582 0.169
V 517.24 60 18.582 0.169
V 517.24 60 18.582 0.169
V 517.25 60 18.412 0.168
V 517.25 60 18.412 0.168
V 517.25 60 18.412 0.168
V 619.2 30 25.183 0.458
V 619.2 30 24.952 0.454
V 619.21 30 25.651 0.467
V 619.21 30 24.952 0.454
V 619.22 30 23.179 0.211
V 619.22 30 23.179 0.211
V 619.22 30 23.394 0.213
V 619.22 30 23.179 0.211
V 619.23 30 23.179 0.211
V 619.23 30 23.394 0.213
V 619.23 30 23.394 0.213
V 619.23 30 23.394 0.213
V 619.24 30 23.610 0.215
V 619.24 30 23.394 0.213
V 619.25 30 23.610 0.215
V 619.25 30 23.610 0.215
V 619.26 30 23.610 0.215
V 619.26 30 23.610 0.215
V 632.98 30 28.386 0.258
V 632.98 30 28.648 0.261
V 632.99 30 29.724 0.270
40 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
V 632.99 30 28.648 0.261
V 633 30 28.386 0.258
V 633 30 28.386 0.258
V 633.01 30 27.359 0.249
V 633.01 30 27.108 0.247
V 633.01 30 26.860 0.244
V 633.01 30 26.613 0.242
V 633.01 30 26.128 0.238
V 633.02 30 26.128 0.238
V 634.98 30 22.341 0.203
V 634.98 30 22.136 0.201
V 635.1 30 26.128 0.476
V 635.1 30 25.651 0.467
V 635.12 30 28.386 0.775
V 635.13 30 29.181 0.797
V 635.13 30 28.648 1.043
V 635.13 30 28.386 1.808
V 635.14 30 29.181 0.797
V 635.14 30 26.613 0.242
V 635.14 30 26.860 0.244
V 635.14 30 27.108 0.247
V 635.15 30 26.860 0.489
V 635.15 30 26.860 0.489
V 635.16 30 26.860 0.489
V 635.16 30 26.369 0.480
V 635.16 30 26.369 0.480
V 635.16 30 26.128 0.476
V 635.17 30 25.651 0.467
V 635.17 30 26.369 0.480
V 635.18 30 26.128 0.238
V 635.18 30 26.369 0.480
V 635.19 30 26.860 0.733
V 635.19 30 26.369 0.720
V 640.21 120 27.868 0.254
V 640.21 120 27.612 0.251
V 641.1 120 32.292 0.294
V 641.11 120 31.996 0.291
V 643.21 120 28.386 0.258
V 643.21 120 28.386 0.258
V 644.1 120 29.181 0.266
V 644.1 120 28.648 0.261
V 648.2 120 28.386 0.258
V 648.2 120 28.914 0.263
V 648.21 120 28.126 0.256
V 648.21 120 28.126 0.256
V 648.22 120 30.839 1.123
V 648.22 120 29.724 0.541
V 651.08 120 33.504 0.915
V 651.08 120 32.591 0.890
V 651.2 120 32.591 0.297
V 651.2 120 33.814 0.308
V 651.21 120 32.591 0.297
V 651.22 120 32.591 0.297
V 651.23 120 32.591 0.297
V 651.23 120 32.591 0.297
V 651.24 120 32.591 0.297
V 651.24 120 32.591 0.297
V 652.07 120 34.762 0.316
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 41
V 652.08 120 34.443 0.313
V 652.2 120 31.124 0.283
V 652.2 120 30.839 0.281
V 652.21 120 31.412 0.286
V 652.21 120 31.124 0.283
V 652.23 120 31.412 0.286
V 652.23 120 31.412 0.286
V 652.24 120 31.124 0.283
V 652.24 120 31.124 0.283
V 655.02 120 25.183 0.229
V 655.02 120 25.183 0.229
V 655.2 120 32.591 0.297
V 655.2 120 32.591 0.297
V 655.21 120 32.292 0.294
V 655.21 120 32.591 0.297
V 655.22 120 32.591 0.297
V 655.22 120 32.591 0.297
V 664.2 30 34.127 0.621
V 664.2 30 34.443 0.627
V 664.21 30 35.083 0.639
V 664.21 30 27.359 0.249
V 678.02 120 35.278 0.498
V 678.02 120 35.083 0.505
V 678.03 120 34.096 0.482
V 678.03 120 34.443 0.506
V 678.05 120 33.783 0.477
V 678.05 120 33.320 0.643
V 678.06 120 33.258 0.757
V 678.06 120 33.258 0.733
V 678.08 120 32.712 0.697
V 678.08 120 32.832 0.846
V 678.09 120 33.106 0.487
V 678.09 120 31.996 1.190
V 678.11 120 32.442 1.289
V 678.11 120 32.174 1.444
V 678.12 120 31.820 0.724
V 678.12 120 31.762 1.101
V 679.07 120 33.075 0.486
V 679.08 120 33.106 0.777
V 679.09 120 30.109 0.944
V 679.1 120 29.316 0.755
V 679.13 120 32.893 0.847
V 679.13 120 31.441 0.568
V 679.14 120 31.239 1.869
V 679.15 120 31.412 0.627
V 680 120 33.075 0.486
V 680.01 120 32.501 0.490
V 680.02 120 32.382 0.625
V 680.02 120 32.772 0.482
V 680.03 120 32.144 0.803
V 680.04 120 32.382 0.646
V 680.05 120 32.263 0.856
V 680.05 120 32.742 0.537
V 680.07 120 32.115 0.472
V 680.07 120 30.726 1.273
V 680.13 120 33.014 0.485
V 680.13 120 32.832 0.483
V 681.09 120 36.805 0.785
42 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
V 681.09 120 37.282 0.821
V 681.1 120 36.300 0.852
V 681.11 120 35.967 0.650
V 681.12 120 37.111 0.985
V 681.12 120 36.635 0.807
V 682.02 120 33.474 0.518
V 682.02 120 34.096 0.491
V 682.03 120 32.292 0.456
V 682.04 120 32.292 0.475
V 682.05 120 31.908 0.451
V 682.05 120 31.732 0.491
V 682.06 120 32.471 0.861
V 682.07 120 31.908 0.494
V 682.09 120 33.474 1.049
V 682.09 120 35.408 1.139
V 682.1 120 33.846 0.770
V 682.1 120 34.127 0.728
V 682.12 120 32.412 0.810
V 682.12 120 32.681 1.051
V 683.01 120 32.352 0.784
V 683.01 120 32.115 0.497
V 683.02 120 31.762 0.723
V 683.04 120 31.499 0.860
V 683.04 120 31.211 0.564
V 683.05 120 30.641 0.450
V 683.05 120 31.355 0.461
V 684.01 120 33.350 0.735
V 684.01 120 33.474 0.473
V 684.03 120 34.666 0.920
V 684.03 120 32.681 0.919
V 684.04 120 34.507 0.997
V 684.04 120 32.561 0.915
V 684.06 120 32.651 0.816
V 684.06 120 31.996 0.874
V 689.01 120 31.849 0.507
V 689.01 120 32.233 0.486
V 689.02 120 31.996 0.470
V 689.03 120 32.352 0.476
V 690.06 120 36.434 0.536
V 690.07 120 36.872 0.555
V 690.07 120 35.769 0.526
V 690.07 120 36.266 0.533
V 690.08 120 35.473 0.549
V 690.09 120 36.000 1.070
V 690.1 120 35.670 0.891
V 690.1 120 35.375 0.911
V 691.05 120 37.351 0.578
V 691.05 120 36.974 0.557
V 691.07 120 37.145 0.560
V 691.07 120 36.838 0.542
V 692.01 120 32.233 0.486
V 692.01 120 33.014 0.526
V 692.03 120 33.412 0.481
V 692.03 120 33.412 0.481
V 692.04 120 33.908 0.556
V 692.05 120 32.412 0.466
V 692.05 120 32.471 0.467
V 692.06 120 34.570 0.508
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 43
V 692.07 120 34.634 0.498
V 692.07 120 33.566 0.483
V 692.08 120 34.285 0.493
V 692.09 120 34.570 0.508
V 692.13 120 31.879 0.846
V 692.13 120 31.557 0.837
V 693.01 120 34.411 0.602
V 693.03 120 34.826 0.695
V 693.03 120 33.628 0.484
V 693.04 120 34.002 0.541
V 693.05 120 33.939 0.488
V 693.06 120 33.443 0.481
V 693.06 120 33.628 0.484
V 693.06 120 33.136 0.477
V 693.08 120 33.535 0.505
V 693.08 120 32.953 0.484
V 693.09 120 32.832 0.593
V 693.1 120 33.075 0.498
V 693.11 120 33.228 0.600
V 693.11 120 32.712 0.894
V 693.12 120 33.197 0.488
V 693.13 120 33.535 0.493
V 694.04 120 34.890 0.513
V 694.04 120 34.762 0.511
V 694.06 120 35.278 0.546
V 694.06 120 34.666 0.510
V 694.07 120 35.343 0.520
V 694.07 120 35.703 0.525
V 694.08 120 35.083 0.516
V 694.08 120 34.987 0.514
V 694.1 120 34.954 0.982
V 694.1 120 35.703 0.525
V 694.11 120 34.222 0.515
V 694.12 120 34.285 0.504
V 694.12 120 34.159 0.515
V 694.13 120 34.443 0.506
V 694.13 120 31.732 0.448
V 695.04 120 34.285 0.504
V 695.04 120 34.507 0.507
V 695.05 120 34.033 0.500
V 695.06 120 34.064 0.501
V 695.07 120 33.939 0.511
V 695.07 120 34.096 0.527
V 695.08 120 33.721 0.496
V 695.09 120 33.721 0.496
V 696.04 120 34.602 0.509
V 696.04 120 34.762 0.511
V 696.05 120 34.826 0.512
V 696.05 120 34.316 0.505
V 696.07 120 34.507 0.520
V 696.07 120 34.666 0.715
V 696.08 120 35.019 0.515
V 696.09 120 35.703 0.689
V 699.02 120 35.245 0.518
V 699.02 120 35.506 0.914
V 699.03 120 35.310 0.519
V 699.03 120 34.411 0.506
V 699.05 120 34.348 0.505
44 A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005
V 699.05 120 34.538 0.508
V 699.06 120 35.083 0.516
V 699.06 120 34.666 0.510
V 699.07 120 33.814 0.497
V 699.07 120 35.148 0.517
V 699.08 120 34.602 0.509
V 699.09 120 35.148 0.517
V 699.1 120 35.604 0.523
V 699.1 120 35.441 0.521
V 700.03 120 35.868 0.527
V 700.03 120 35.441 0.521
V 700.04 120 35.525 0.530
V 700.04 120 34.922 0.513
V 700.06 120 34.634 0.522
V 700.06 120 35.019 0.527
V 700.07 120 34.380 0.505
V 700.07 120 34.634 0.669
V 700.08 120 34.253 0.504
V 700.09 120 34.890 0.610
V 700.1 120 34.858 0.845
V 700.1 120 33.908 0.511
V 701.02 120 32.203 0.513
V 701.02 120 32.501 0.490
V 701.03 120 32.292 0.486
V 701.04 120 31.791 0.479
V 701.05 120 32.501 0.490
V 701.05 120 32.712 0.972
V 701.06 120 31.326 0.585
V 701.08 120 32.115 0.852
V 701.08 120 32.893 0.484
V 702.03 120 35.051 0.515
V 702.03 120 35.834 0.527
V 702.04 120 35.769 0.526
V 702.04 120 35.148 0.517
V 702.06 120 35.736 0.525
V 702.06 120 35.901 0.716
V 702.07 120 35.571 0.809
V 702.07 120 35.245 0.531
V 703.03 120 31.211 0.459
V 703.04 120 31.703 0.916
V 703.05 120 30.613 0.740
V 703.05 120 31.470 0.739
V 703.06 120 30.924 0.541
V 703.07 120 31.879 0.595
V 703.07 120 31.791 0.747
V 703.07 120 31.067 0.468
V 704.03 120 31.239 0.459
V 704.03 120 31.067 0.457
V 704.05 120 31.239 0.459
V 704.05 120 31.239 0.666
V 704.06 120 31.441 0.474
V 704.06 120 31.470 0.445
V 704.07 120 31.616 0.590
V 704.07 120 31.268 0.498
V 710.06 120 29.669 0.447
V 710.07 120 29.154 0.601
V 711.07 120 31.586 0.765
V 711.07 120 31.674 0.941
A. Dolcini et al.: REM monitoring of PKS2155-304 during 2005 45
V 715.03 120 31.703 0.592
V 715.03 120 32.442 0.990
V 715.04 120 31.820 0.771
V 715.04 120 31.967 0.638
V 721.05 120 29.806 0.678
V 721.05 120 30.248 0.710
V 722.05 120 32.591 0.695
V 722.05 120 32.681 0.590
V 723.05 120 32.115 0.754
V 723.05 120 31.820 0.724
Table A.1: Log of observations. Epoch of observations is reported in JD-
2453000.5 unit.
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	Introduction
	REM, Photometric procedure, data analysis
	Observations and data analysis
	Results
	Long term variability
	Short time-scale variability
	The NIR-Optical spectral energy distribution
	Discussion
	Table of observations
