bluuebunny/crossref_metadata_2025 huggingface dataset:
Observational Constraints on Mode Excitation in δ-Scuti Stars In Open Clusters
Authors: Frandsen S. , Kjeldsen H.
Published: July 2016

The special opportunities offered by δ-Scuti stars are the following:

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They regularly oscillate in several modes, and with high precision observations one has measured of the order 5 modes (Michel and Baglin 1991

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The excitation is a very delicate and therefore a very sensitive measure of the internal structure.

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They are found in open clusters which constitute a very rich scenario for tests of the theory of stellar structure and evolution. This makes it feasible to observe several stars simultaneously and gain more results than for single stars.

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The brightness is moderately high and still they live long enough to be present in a variety of clusters and in the field as well.
Absolute Magnitude Determination of Be Stars: The Inadequacy of the 2200 Å Bump
Authors: Doazan V. , De La Fuente A. , Barylak M. , Cramer N.
Published: July 2016

We present fax UV observations of Pleione made with the IUE satellite at two epochs: in 1979, when the star exhibited a strong shell spectrum and, in 1991, when it showed a Be-type spectrum. Between these two epochs, the 2200 Å bump changed dramatically, thus, rendering it inadequate for interstellar extinction/distance determination.
The Nobeyama Millimeter Array
Authors: Morita Koh-Ichiro
Published: July 2016

The present status and the upgrading projects for the Nobeyama Millimeter Array are described. The array is currently being upgraded to produce higher sensitivity and new spectral windows. The major items have been a new 10-m antenna, new receivers, and a new correlator. There follows a brief summary of the astronomical research is presented.
The CSO-JCMT Submillimeter Interferometer
Authors: Carlstrom J. E. , Hills R. E. , Lay O. P. , Force B. , Hall C.G. , Phillips T. G. , Schinckel A. E.
Published: July 2016

A linked submillimeter-wave interferometer using the CSO 10.4 m and the JCMT 15 m telescopes located on Mauna Kea at an elevation of 4200 m, has been built and tested successfully. The capabilities of the instrument and an outline of the type of observations that can be made with a single, fixed-baseline interferometer are given. In particular, an experiment to detect gas infalling onto low-mass protostellar sources is proposed. The design of the instrument is described briefly and the successful results of the first tests are summarized.
The 6m mm-VLBI telescope at Kagoshima, Japan
Authors: Omodaka Toshihiro , Morimoto Masaki , Kawaguchi Noriyuki , Kitamura Yoshimi , Tanaka Minoru , Kuji Seisuke , Miyazawa Keisuke , Miyaji Takeshi , Mikoshiba Hiroshi , Hayashi Risao , Kitagawa Takahiro , Maneki Jyunya , Suzuyama Tomoya , Inoue Makoto , Fujishita Mitsumi , Sasao Tetsuo , Furuya Ley , Miyasato Kazuhide , Jike Takaaki
Published: July 2016

VLBI observations of millimeter wavelengths can probe the broad line emission and jet forming regions of quasars, and the scale of an accretion disk around massive black holes in nearby active galaxies, which are self-absorbed at longer wavelengths. Therefore, the extension of the mm-VLBI network is timely and urgent problem. We are now planning to move Nobeyama 6 m mm VLBI telescope to Kagoshima. The telescope will be placed at Kinkohwan park in Kagoshima City in late 1992 and will be operated in 1993. The frequencies for VLBI observations will range from 22 GHz to 100 GHz.

To date, there are two mm-VLBI facilities in Japan: Nobeyama 45 m and Kashima 34 m, However, the longest baseline is only about 200km EW which provides a fringe separation of 17 mas. This is not sufficient for high resolution mapping. A 10 m telescope which is under construction at Mizusawa, 400 km north from Kashima which will be usable up to 43 GHz and will add a north-south baseline, which is very important for astrometrie measurement.
Mosaicing: Current Status
Authors: Cornwell T.J.
Published: July 2016

Over the past several years, there has been substantial progress both in algorithms for mosaicing and in our understanding of the effects of errors on mosaiced image. I describe the current state of knowledge in both these areas and also indicate where future improvements are likely to lie.
IF Fiber Optics and Digital Correlating Spectrometer on the JCMT-CSO Interferometer
Authors: Lay O.P. , Hills R.E. , Carlstrom J.
Published: July 2016

This paper describes the delay lines designed and built for the JCMT-CSO submillimeter interferometer located on the summit of Mauna Kea, Hawaii and described in the paper by Carlstrom et al. in these proceedings.

One of the major features of the project is the use of fiber optics instead of coaxial cable to bring the IF signals (l-2GHz) from the receivers to the spectral line correlator via a set of fiber optic delay lines. Optical fiber now has many advantages over coax including very large bandwidth, low loss, economical cost and size and immunity to electrical interference.

Soares et al. (these proceedings) describe a delay line system that can be used with a broadband continuum correlator requiring very fine delay steps The JCMT-CSO interferometer was intended to be used primarily with a digital correlating spectrometer that has a range of built-in delays, greatly easing the demand on delay line resolution.
The Massive Cloud Core Sgr B2(M): Starburst Triggered by a Cloud Collision
Authors: Miyawaki Ryosuke , Hasegawa Tetsuo , Sato Fumio , Whiteoak John B. , Kobayashi Hideyuki
Published: July 2016

We have observed Sgr B2 with NMA.Blue- and redshifted features revel the structure of massive core. Massive core was formed by a cloud collision and massive star formation took place by means of collapse of massive core.
An Accretion Disk Model for the Innermost 200PC of the Galaxy
Authors: Duschl W.J. , Linden S.v. , Biermann P.L.
Published: July 2016

We demonstrate that it is possible to understand observed radial velocities of molecular clouds close to the Galactic Center as being due to motion of this material in an accretion disk. Our models indicate a stationary disk with a radial mass flow rate of 10-1.8 Mʘ/yr with a viscosity of 1.9 · 103 pc km/s at 100 pc from the Galactic Center and a radial dependence of it, that goes approximately like the square root of the radius from the Galactic Center.
Massive Star Formation
Authors: Vogel Stuart N.
Published: July 2016

Several topics in massive star formation are discussed. These include chemical markers of the evolutionary state of massive protostellar cores, kinematic evidence for gravitational collapse, and studies of massive star formation in different environments.
Molecular Outflows in B335 and B1
Authors: Hirano N. , Kameya O. , Kasuga T. , Mikami H. , Saito S. , Umemoto T. , Yamamoto S.
Published: July 2016

We present the aperture synthesis observations of the CO molecular outflows associated with the low-mass young stellar objects embedded in B335 and Bl. We used the Nobeyama Millimeter Array and obtained the angular resolutions of 8.1” × 5.0” for B335 and 6.5” × 4.4” for B1.
Aperture Synthesis Maps of NH2D and CH3OD Lines Toward Orion-KL: The Origin of NH3 and CH3OH
Authors: Saito S. , Mikami H. , Yamamoto S. , Murata Y. , Kawabe R.
Published: July 2016

The 111−-101+ transition of NH2D and the 21−20 E transition of CH3OD were mapped toward Orion-KL with the Nobeyama Millimeter Array. The synthesized beamwidth is 4″ to 5″. NH2D and CH3OD are mainly distributed over the peak-intensity regions of NH3 and CH3OH in Orion A, respectively. These results suggest that “most” of the gas-phase ammonia and methanol in the region of Orion-KL originate from dust grains.
A Flattened Cloud Core in NGC 2024
Authors: Ho P. T. P. , Peng Y-L. , Torrelles J. M. , Gómez J. F. , Rodríguez L. F. , Cantó J.
Published: July 2016

With the VLA in the D configuration we have mapped the (J,K) = (1,1) and (2,2) NH3 lines toward a molecular cloud core in NGC 2024. This region, which contains one of the most highly collimated molecular outflows (Richer et al. 1992), has been studied extensively using a variety of techniques, including dust continuum in the far-infrared (FIR) wavelengths (Mezger et al. 1988, 1992), and molecular lines (see Barnes & Crutcher 1992 and references therein). We find that the molecular condensations associated with FIR 5, 6, and 7 (Mezger et al. 1988, 1992) have kinetic temperatures TK ≃ 40 K. We also find a perturbation of the molecular gas near FIR 6 and FIR 7 in terms of broadening of the ammonia lines. These results suggest that these condensations may not be protostars heated by gravitational energy released during collapse, but that they have an internal heating source. A flattened structure of ammonia emission is found extending parallel to the unipolar CO outflow structure, but displaced systematically to the east. The location of the high velocity outflow along the surface of the NH3 structure suggests that a wind is sweeping material from the surface of this elongated cloud core. Figure 1 is an overlay of the VLA ammonia emission (dotted area) on top of the C18O emission (thick contours) and the CO outflow (thin contours).
Snapshot Observations of Circumstellar Material Around Young Stellar Objects
Authors: Despois D. , Masset F. , André P. , Baudry A. , Montmerle T. , Cabrit S.
Published: July 2016

We have undertaken 3mm continuum and 13CO line observations of 10 Young Stellar Objects with the Plateau de Bure Interferometer (PdBI) in a snapshot mode. We discuss here mainly the continuum dust emission (opacity index β and source extent).
The Clouds of M 82
Authors: Schilke P. , Brouillet N. , Baudry A.
Published: July 2016

All the existing molecular maps of M82 made up to now have revealed a double-lobed stucture interpreted as a uniform torus (Nakai et al. 1987). We have observed the central part of M 82 in the HCN (J=1−0) line with the Plateau de Bure IRAM interferometer (spatial resolution = 2.5″). The HCN molecule, due to its high dipole moment, traces clumps with a density of about 105 cm−3. For technical reasons we have divided our study in two fields. We present here the results obtained in the south-west field, covering one lobe of the “molecular ring” and the center of the galaxy in the velocity range 0-260 km s−1.
The Starburst in the Nucleus of NGC 6764: The Near-IR/Radio/Optical Connection
Authors: Cameron Murray , Eckart Andreas , Genzel Reinhard , Nakai Naomasa , Wagner Stefan
Published: July 2016

Knowledge of the distribution and excitation of gas close to the nuclei of starburst galaxies is an essential element in the construction of models dealing with intense, but short-lived, star forming events. Building a comprehensive picture of the concentrations of various gaseous components in such regions calls for a multi-wavelength approach: the principal cooling lines of cold (T≤200K) molecular gas fall in the millimetre waveband, those of hot (T~1−3×103K) excited molecular material in the near-IR, and those pinpointing starburst activity in the optical. In many cases the extents of the emitting regions are on the order of only a few arcseconds.

As part of such a study into the relationship between various near- and circum- nuclear gaseous components in starburst galaxies, we have obtained data on NGC 6764, a barred spiral classified as a LINER, at resolutions of 1″−4″ across the optical, near-infrared and millimetre wavelength regimes. In a previous paper (Eckart et al. 1991) we discussed extensive single dish millimetre and JHK near-IR measurements of the nucleus and disk of NGC 6764. Here we present new near-IR observations obtained with the MPE FAST instrument (Rotaciuc et al. 1991) at the William Herschel Telescope, along with 2″ resolution 12CO J=1-0 (115 GHz) interferometry measured with the Nobeyama millimeter array and 1″ optical spectroscopy from the 3.5m Calar Alto telescope.
Detection of Interarm Molecular Clouds in M51: MSC OR GMC?
Authors: Tosaki T. , Taniguchi Y. , Kawabe R.
Published: July 2016

In our Galaxy, molecular gas forms clouds with masses of ~ 105M© and with sizes of several 10 pc, which are called Giant Molecular Clouds (Sanders 1985; hereafter GMCs). Such GMCs are also observed in nearby spiral galaxies M31 and M33 (Lada et al. 1988; Wilson & Scoville 1990). On the other hand, one of the well-studied spiral galaxy M51 has more massive and larger molecular clouds. Since their typical mass and size are 107-8MQ and several 100 pc, respectively, they are called Molecular Superclouds (Rand & Kulkarni 1990; Tosaki et al. 1992; hereafter, MSCs). A question arises as what causes the difference in structural properties of molecular gas among the spiral galaxies. In order to answer this question, we should make higher resolution studies both spatially and spectroscopically. In this paper, we present the results of high spectral-resolution study of the MSCs in M51 based on the 12CO (J = 1 − 0) mapping made with the Nobeyama Millimeter Array (Tosaki et al. 1992). The spatial resolution is 5.”3×4.”9 corresponding to 240 × 230 pc at distance of 9.6 Mpc. The spectral resolution is 3.25 km s−1. The analysis is made for the 1’ region whose center is offset 42” south and 7” east from the nucleus, because a very intense molecular arm is present in this region. Our Main results and conclusions are as follows.
SOFIA: Stratospheric Observatory for Infrared Astronomy
Authors: Davidson J. A. , Erickson E. F.
Published: July 2016

SOFIA will be a 2.5 meter telescope installed in a Boeing 747 aircraft. It will replace NASA’s smaller Kuiper Airborne Observatory (KAO), which for the past 18 years has provided the only routine access to most of the vital infrared spectrum (1 - 1000 µm). The aircraft platform opens a valuable window to the universe by enabling measurements of infrared radiation from celestial sources which the Earth’s atmosphere absorbs at lower altitudes. SOFIA will have 10 times the sensitivity and 3 times the angular resolution of the KAO throughout most of the infrared spectrum.

SOFIA will be operated during its 20 year lifetime as an international facility for astronomy. It would fly 160 astronomy missions per year for about 50 science teams, selected by annual peer review. Nearly a third of these teams will furnish the observatory with specialized instrumentation, including array cameras, polarimeters, and several types of spectrometers. The frequent flight opportunities with state-of-the-art instruments guarantee extensive community participation and hands-on training of young scientists.
Hg-Mn Stars Versus Normal Stars
Authors: Dworetsky M.M.
Published: July 2016

The literature concerning spectroscopic studies, abundances, photometry and systematics of Hg-Mn stars is reviewed since the last international meeting on chemically peculiar stars in the Crimea in 1985, and is intended to be complete to the end of 1991.
Exploring Abundance and Isotope Anomalies in CP Stars with the HST/GHRS: High Resolution UV Spectroscopy of χ Lupi
Authors: Leckrone David S. , Wahlgren Glenn M. , Johansson Sveneric G. , Adelman Saul J.
Published: July 2016

We are using the HST/GHRS in a long-term program to obtain UV spectra of unprecedented resolution and precision for bright, ultra-sharp-lined Bp (HgMn) stars and comparable normal stars. To date we have doubled the number of heavy elements for which abundances may be estimated in χ Lupi, and have obtained the first observations of Hg III lines with which to test diffusion scenarios for its extreme Hg isotope anomaly.
Similarities and Differences between Magnetic and Non-Magnetic CP Stars
Authors: Lanz Thierry
Published: July 2016

This brief review discusses the similarities between CP stars, focusing on magnetic fields and chemical abundances. New evidence for the presence of a magnetic field with a complex structure in some CP1 stars is presented. Small-scale structures on the surface of these stars may be connected with such a field, and the resulting effects on the curve-of-growth have been investigated. Finally, the changes during evolutionary time-scales on surface abundances are advocated as one possible reason of the large observed scatter in the chemical anomalies inside given groups of CP Stars.
How Normal are the Peculiar a Stars
Authors: Babu G.S.D. , Shylaja B.S.
Published: July 2016

A comparison of various physical parameters of the normal A stars with those obtained by using the peculiarity-free zones of Ap stars indicate that the peculiar A stars may be treated as normal stars as far as their effective temperatures, radii, bolometric corrections and the mass range are concerned.
The Impact of Reddening on the Observed Fluxes of a Stars
Authors: Bonifacio Piercarlo , Castelli Fiorella
Published: July 2016

We compare observed ultraviolet and visible flux distributions, for a sample of A-type stars, with computed fluxes obtained with version 9 of the ATLAS code (Kurucz, 1970) in order to asses the impact of reddening. We also make a comparison between determinations of reddening from UV colour indices and visible wide band (Johnson) and intermediate band (Strömgren) colour indices. We discuss the implications on the study of slightly reddened high galactic latitude stars.
The Colors of Am Stars
Authors: Shylaja B.S. , Babu G.S.D.
Published: July 2016

The energy distribution of the Am stars are affected by the line blanketing, which appears as a deviation in the behaviour of color indices with reference to the normal stars. In this paper we study the various color indices along with the data from IRAS and try to identify a realistic representative of the effective temperature. An excess in the IR also becomes apparent in some cases.
The Effective Temperature of Am Stars
Authors: Megessier C. , van’t Veer C.
Published: July 2016

The values of the effective temperature derived for Am stars by the infra-red flux method and from the Balmer line profiles are in very good agreement. They are hotter by more than 300K than the Teff given by Lane and Lester (1984) and cooler by about 200K than those obtained by Dworetsky et al (1986).
Elemental Abundances of Sharp-Lined Metallic-Lined and Comparable Normal Stars
Authors: Koçer Dursun , Adelman Saul J. , Bolcal Çetin , Hill Graham
Published: July 2016

We are performing elemental abundances of sharp-lined metallic-lined stars and normal late A through middle F stars using 2.4 Å mm−1 photographic region spectrograms taken with the coudé spectrograph of the 1.4-m telescope of the Dominion Astrophysical Observatory. Our initial studies of the Am stars 15 Vul and 32 Aqr and the normal stars θ Cyg (F4 V) and ɩ Psc (F7 V) showed that the elemental abundances of the normal stars were close to solar while 15 Vul shows smaller abundance anomalies than does 32 Aqr. These analyses are being done consistently with SJA’s studies of the HgMn and hotter normal stars.
Stellar Spots-Heating and Cooling Diamagnetically
Authors: Steinitz Raphael , Goldstein Ulzan
Published: July 2016

Diamagnetic effects as heating and cooling mechanisms at stellar surfaces have been ignored in the past. This is due to the misconseption that the effect, when averaged over a velocity distribution, vanishes. We explore here the relevance of the effect to the observed luminosity and color modulations observed in CP stars.
A New Model for Stellar Magnetism
Authors: Browne P.F.
Published: July 2016

Different drift velocities of electrons and ions in response to viscous forces exerted by neutral atoms generate current density j and magnetic field B, where B is proportional to vorticity ω of the fluid. Magnetic vortex tubes (MVTs) form arrays on a hierarchy of scales. MVTs are basic to the magnetism of all astrophysical systems, conferring a structure of aligned filaments. In the Sun a torsional oscillation generates oscillatory vorticity, and hence an oscillatory magnetic field. The same mechanism is proposed for the Ap stars, but with “pole-on” viewing. Resonance-line radiation pressure segregates elements within MVTs of Ap stars, where the anomalous concentrations are preserved. However, variation of the 30 MG magnetic fields of AM Her white dwarfs may be due to precession of an MVT. There is reason to attribute common magnetic flux to the Sun, Ap stars, white dwarfs and neutron stars
Have Non-Magnetic Stars a Complex Geometry?
Authors: Catalano Francesco A.
Published: July 2016

The existence of non-magnetic CP stars among the ones in the CP2 and CP4 groups is discussed. Assuming to be non-magnetic a star in which the magnetic field has been measured but no value in excess of the 3σlevel has been detected, the implications of the spectrum and/or light variability observed in some such stars are discussed. Since the overall properties ofnon-magneticstars do not differ significantly from those of the magnetic ones and a similar variability phenomenology has been observed in several such stars, the probable presence of a weak large scale organized magnetic field is argued.
Parameters Teff and L/L⊙ for a Group of λ Bootis Candidate Stars and their Evolutionary Status
Authors: Gerbaldi M. , Zorec J. , Castelli F. , Faraggiana R.
Published: July 2016

The Teff value, according to the definition of this parameter, is computed with the procedure described; the observations are then compared with the flux distribution from Kurucz’ LTE blanketed models for various values of the metallicity parameter [Z/H].

Then we derive the bolometric luminosity L/L⊙ by combining the stellar bolometric flux with the values of the trigonometric parallaxes and of the colour excess found in the literature. These luminosities are then plotted on evolutionary sequences; from the position of some λ Boo stars (ρ Vir and π1 Ori), we argue that their evolutionary stage, if interpreted as that of stars having left the main sequence, is too late to keep the λ Boo abundance anomalies.

These same λ Boo stars, plotted on pre-main sequence evolutionary tracks, would indicate increasing λ Boo character when the stars are approaching the main sequence showing the strongest character in λ Boo and 29 Cyg, the two stars nearest the ZAMS.
Steady State Diffusion Processes Under Turbulent Conditions. Gallium and Aluminium Cases
Authors: Budaj Ján , Zboril Milan , Zverko Juraj , Žižňovský Jozef , Klačka Jozef
Published: July 2016

The stationary state of the element stratification under appropriate turbulence is investigated. Equation of the stationary state is derived and solved under several simplifications. Cases of Ga and Al are studied. Al is predicted to be underabundant, but the abundance is rising with decreasing effective temperatures of the stars. Different results obtained using two methods of finding the stationary Ga stratification are indicated.
Spectral Diagnoses of Chromospheres and Winds in A-Type Stars
Authors: Lanz Thierry , Hubeny Ivan
Published: July 2016

So far, neither chromospheres nor stellar winds have been directly detected in main-sequence A stars. While radiative diffusion requires extremely weak stellar winds to reproduce chemical anomalies (10−15 to 10−12M⊙yr−1), two independent direct searches for mass loss set up upper limits to 10−10 M⊙yr−1, which is still several orders of magnitude higher. We discuss some new recent possibilities to detect chromospheres which arise thanks to new NLTE model atmospheres. In the near future, some progress is also expected from new observations of Lyman α with HST and from the increased sensitivity of ROSAT in the X-ray domain.
Periodic Radio Emission from the Helium Rich Stars HD 37017 and σ Ori E
Authors: Leone Francesco , Umana Grazia
Published: July 2016

Drake et al. (1987) detected, for the first time, radio emission from magnetic Chemically Peculiar stars. They suggested that radio emission is consistent with gyrosynchrotron emission from continuously injected, mildly, relativistic particles trapped in a magnetic equatorial belt.

Leone (1991) showed that it is possible considering that the radio emission comes from magnetic poles and is due to the electron component of the wind flowing along the open field lines. As a consequence Leone (1991) put forward the hypothesis that such emission could be periodically variable.

In order to verify the surmise of a periodic radio emission, the magnetic Chemically Peculiar stars HD 37017 and σ Ori E have been monitored with the VLA at 6 cm.

By combining our data with those obtained by Drake et al. (1987) and Philips & Lestrade (1988), we show that the radio emission from HD 37017 and σ Ori E varies with the rotational period.
Opacity Problems in Cool Low Mass Stars
Authors: Scholz Michael , Wehrse Rainer
Published: July 2016

In this contribution we want to discuss M star atmospheres and their dependence on molecular opacities. A star belongs to the spectral class M if its optical and infrared spectrum shows strong bands of TiO and numerous strong metal lines so that for wavelengths < 4000 Å there is “hardly any flux left” (Jaschek & Jaschek 1987). M stars cover a very large range in luminosity: M dwarfs are the intrinsically faintest stars, whereas M giants and supergiants reach luminosities that are among the highest known. General properties of these objects are given in Table 1 (after Schmidt-Kaler 1982).
White Dwarfs
Authors: Thejll Peter
Published: July 2016

It is the intention of this review to explain what white dwarfs are and why it is interesting to study them, and why the H+2molecule is of special interest.

The evolution, from start to finish, of a star of mass less than about 2 solar masses (M⊙), can roughly be summarized as follows:

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A cloud of gas contracts from the interstellar medium until hydrogen ignites at the center and amain sequence(MS) star forms. H is transformed to He and the MS phase continues until H is exhausted in the stellar core.

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H continues burning in a shell outside the He core while the core contracts. He “ashes” are added to the core, and ared giantstar is formed as the envelope expands. The star evolves up the Red Giant Branch (RGB) (i.e. it becomes more and more luminous and the surface cools).

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Towards the end of the RGB phase, mass-loss from the upper layers increases until helium to carbon burning in the core ignites suddenly under degenerate conditions – this is called theHelium Flash(HF). The HF terminates the RGB evolution, and therefore also the mass-loss and the growth of the stellar core.

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The star readjusts its structure and the He-core burns steadily on thehorizontal branch(HB) (a phase of nearly-constant luminosity) until fuel is exhausted in the He-core.

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Then the C/O core contracts anew and the expansion of the envelope, and the growth of the core, during He-shell burning, mimics RGB evolution but relatively little mass is added to the core this time.

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The second ascent of the giant branch (the so-called Asymptotic Giant Branch, or AGB) continues with increased mass loss towards the end

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Rapid detachment of a considerable fraction of the remaining envelope and the hot core takes place, sometimes observable as thePlanetary Nebulae(PN) phase.

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The PN is dispersed as the core contracts to a white dwarf (WD).

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The WD cools for a long time, as internal kinetic energy and latent heat is released.
Opacity Problems in Protostellar Objects
Authors: Yorke Harold W. , Henning Thomas
Published: July 2016

Opacity influences the transfer of radiation and is thus of decisive importance for (a) the interpretation of astronomical observations, (b) determining the thermal structure, (c) critically influencing molecular, atomic and thermonuclear processes and (d) affecting the overall dynamic evolution during the star formation process. Questions pertaining to the onset of instability of gas clouds, their subsequent fragmentation into smaller clumps, the formation of multiple systems, the initial mass function (IMF), the upper and lower mass limits, star formation efficiency and the fate of material not collected into stars cannot be considered without intimate knowledge of the opacity in this environment.
Molecules in the Sun and Molecular Data
Authors: Grevesse Nicolas , Sauval A. Jacques
Published: July 2016

Molecules play a unique role in solar spectroscopy in allowing to derive, with high accuracy, the temperature structure of the photospheric layers from where the solar spectrum in the near ultraviolet, visible and infrared emerges. They also allow to observe the heterogeneous structure of the outer layers as well as the subtle convective motions in the layers just above the solar convection zone. Molecules play also a unique role in defining the solar chemical composition, at least as far as the very important elements like carbon, nitrogen and oxygen are concerned. They also offer the unique opportunity to derive meaningful isotopic ratios for C and O. Although we shall not deal with sunspots in the present review, it has to be recalled that molecules are the only tracers to derive the solar abundances of CI and F from the rotation-vibration lines of HC1 and HF present in the infrared sunspot spectra (Hall & Noyes 1972; Hall & Noyes 1969).

On the other hand, the Sun itself offers a unique opportunity to produce molecular transitions, in local thermodynamic equilibrium (LTE), at rather high temperatures (T ∼ 5000 K), higher in any case than in the laboratory, often in non LTE (see review by Johnson in this volume). Therefore, new lines and new transitions of higher excitation appear in the solar spectrum allowing to use the Sun as a “permanent laboratory source” in order to refine the molecular constants. Furthermore, the solar photosphere, where we believe the physical conditions and physical processes are better known than in any other stars, offers a unique possiblity to test basic molecular data like dissociation energies and transition probabilities.
Effects of Non-Local Thermodynamic Equilibrium (NLTE) on Molecular Opacities
Authors: Johnson Hollis R.
Published: July 2016

Molecules increase in importance in stellar atmospheres as the temperature falls along the spectral sequence for all luminosity classes. Among their many roles molecular features provide the basis for spectral classification (temperature and chemical composition) in M, S, and C stars; they constitute important opacity sources across the spectrum from the ultraviolet to the infrared; they influence the energy budget and hence the kinetic temperature in the outer photospheric layers; they may contribute significantly to the radiative levitation of the atmosphere; they form masers; they may cause or facilitate mass loss; and they are indicative of physical conditions and processes from the photosphere to the outer circumstellar envelope.
The Berkeley Program on Molecules of Astrophysical Interest
Authors: Davis Sumner P.
Published: July 2016

A systematic program of laboratory analyses of selected molecular spectra of astrophysical interest started in 1958 and continues to the present time. The program includes production of spectral atlases, tabulations of spectral lines, analyses, calculations of excitation energies and molecular parameters, measurements of radiative lifetimes, and determinations of transition strengths. Work has been completed or is in progress on the spectra of ArH+, C2, carbon clusters, CN, CS, CaCl, CaH, CaS, FeD, FeH, HgH, HgD, InI, LaO, LaS, OD, OH, SH, Si2, SiC2, TiCl, TiO, TiO+, VO, YS, ZrCl, ZrO, and ZrS. The basic needs for astronomically useful data have not changed, but laboratory and analysis methods have become more sophisticated in order to cope with ever greater demands for consistency, accuracy, and breadth of information. The Fourier transform spectrometer and computer codes for analyses have enhanced our ability to satisfy some of these demands.
A Search for M32-like Galaxies in the Fornax Cluster using Flair
Authors: Holman Brett , Drinkwater Michael , Gregg Michael
Published: July 2016

Results of a spectroscopic search for M32-like compact elliptical galaxies in the Fornax cluster are presented. None were found, which suggests that these objects represent the low luminosity end of the giant elliptical luminosity function, rather than being formed by tidal stripping. The sample is used to investigate the large-scale distribution of bright ellipticals.
A Magnitude Limited Redshift Survey near the SGP
Authors: Parker Quentin A.
Published: July 2016

A description of a magnitude limited redshift survey covering 9 adjacent UKST fields is presented together with some initial results. The survey is currently ∼ 90% complete to bj ≤ 17.1. The compilation of ∼ 1700 redshifts will form one of the largest, independent, contiguous, well sampled and most homogeneous redshift catalogues currently available. The special features of this catalogue are its coverage (∼ 330deg2), mean sampling depth (∼ 125h–1 Mpc) and field to field photometric accuracy (bj ± 0.05). Morphological classifications have also been determined for all galaxies in the survey fields down to bj ≤ 17.1 and COSMOS image parameters are also available. This extensive catalogue should prove a valuable database for many projects but particularly in delineating the detailed structure in the large scale galaxy distribution.
Schmidt Telescope Plate Archives
Authors: Tsvetkov Milcho , Stavrev Konstantin , Tsvetkova Katya , Mutafov Asen , Michailov Michail-Ernesto
Published: July 2016

The contemporary state of the Schmidt/Maksutov telescope plate archives and their unification in an Index Plate Catalogue as part of the Wide Field Plate Database is presented.
A Southern Digital Sky Survey Using the UK Schmidt Telescope
Authors: Peterson Bruce A.
Published: July 2016

Two CCD detector systems for the U. K. Schmidt Telescope that would allow a southern digital sky sulvey of faint objects to be carried out are described.
Searching for Near-Earth Asteroids with the UK Schmidt Telescope at the AAO
Authors: Steel D. I. , McNaught R. H. , Garradd G. J. , Russell K. S. , Asher D. J.
Published: July 2016

Since 1990 we have operated a program in which all plates and films exposed at the 1.2 m U.K. Schmidt Telescope (UKST) are searched for suspicious trails that may represent fast-moving (Earth-approaching) objects. When a possible near-Earth asteroid is discovered, we obtain follow-up astrometric positions using photography on either the UKST (if the object is faint) or the 0.5 m Uppsala Southern Schmidt at the same site. Further astrometric positions, once a reasonable ephemeris is available, are obtained with a large-format CCD on the 40 inch telescope of the Siding Spring Observatory (SSO).

In the near term we plan to extend our use of the UKST making use of time near bright-of-moon when the telescope is currently underused. We will conduct photographic searching by taking dedicated films in pairs of 5-10 minutes exposure, with 30-60 minutes gaps between. These will then be inspected using electronically blinked video cameras to scan the films and look for objects that have moved between the exposures. We believe that we can better than triple our current discovery rate (which is about 8-10 near-Earth asteroids per year) in this way.

In the longer term clearly the installation of a mosaic of CCDs covering some reasonable fraction of the UKST focal surface is a desideratum, and this is under consideration.
An attempt to Derive the Proper Motion for Blanco Cluster 1
Authors: Hidayat Bambang , Wiyanto Paulus
Published: July 2016

In order to establish the probability of physical membership of open clusters by means of astrometrical methods, two criteria are used: the position distribution of stars in the sky and their proper motions. Proper motion methods have shown validity from a practical point of view; but are difficult to apply where there is a high ratio of cluster-to-field stars, and in crowded fields of the Milky Way.

As a test we have selected the nearby (170–190 pc) Blanco Cluster 1 (1 = 16°, b = −73°) in order to avoid complications arising from crowded fields. Photometric data however, suggests that the diameter of the cluster is rather extended (~ 120 arcsec). This will require a large-field solution, rather than a small-field solution which can be obtained with greater accuracy using Schmidt astrometry (Fresneau 1978; Nakamura & Sekiguchi 1993).
Astrometric Programmes of the Abastumani Observatory
Authors: Chanturiya Soso M. , Inasaridze Raguli I. , Kiladze Rolan I. , Kurtanidze Omar M.
Published: July 2016

Astrometric investigations undertaken with the 70 cm meniscus and 40 cm double astrograph telescopes are considered. We describe the determination of accurate positions for minor planets, giant-planet satellites, late-type stars, extragalactic radio-sources, optically discovered quasars and compact extragalactic objects in the Second Byurakan Survey.
The Tautenburg Schmidt Telescope and Galactic Proper Motion Studies
Authors: Schilbach E. , Scholz R.-D. , Hirte S.
Published: July 2016

The combination of Tautenburg plates and automatic measuring machines provides a powerful tool to obtain photometry and proper motions of a great number of stars for statistical investigations of our Galaxy. Photographic photometry with an accuracy of about 0.07 mag can be obtained provided two plates of the same colour and a sufficient number of photometric standards are available. With two plate pairs and a 20 years baseline, a proper motion accuracy better than 4 mas/year can be achieved for stars over a wide range of magnitudes. Outside the Galactic plane proper motions are determined with respect to hundreds of background galaxies.
The Edinburgh-Cape Blue Object Survey
Authors: Stobie R. S. , Kilkenny D. , O’Donoghue D. , Chen A.
Published: July 2016

The Edinburgh-Cape Blue Object Survey is a major survey to discover blue stellar objects brighter than B ∼ 18 in the southern sky. It covers an area of sky of 10,000 square degrees with |b| > 30° and δ < 0°. The blue stellar objects are selected by automatic techniques from U and B pairs of UK Schmidt Telescope plates scanned with the COSMOS measuring machine. Follow-up photometry and spectroscopy are being obtained with the SAAO telescopes to classify objects brighter than B = 16.5. This paper describes the survey, the techniques used to extract the blue stellar objects, the photometric accuracy, and the completeness of the survey.
Aitoff Projection Plots and Other Statistical Results for Stars in Volumes 1–4 of the Michigan Catalogue of MK Types for the HD Stars
Authors: Houk N. , Sowell J. , Austin S.
Published: July 2016

The approximately 130,000 HD stars between declinations −90° and −12° have been classified on the MK system. This large, consistently classified database has been used to examine the distribution of the stars in galactic coordinates by using Aitoff equal area plots. Both normal stars, grouped by similar temperature and luminosity types, and peculiar stars of various types, will be displayed. The plots will be published in the Astronomical Journal, rather than in these Colloquium Proceedings.
A Near–IR Survey of the Southern Galactic Plane
Authors: MacConnell D. Jack , Wing Robert F. , Edgardo Costa H.
Published: July 2016

We describe a long term project to find faint, heavily-reddened, cool supergiants and carbon stars and to classify IRAS Point Sources within 6° of the southern galactic plane. Many new supergiants and carbon stars have been found, and thousands of IRAS Point Sources have had their spectral types determined.
A Large Number of Herbig-Haro Candidates Found by the Contrast Enhancement and Unsharp Masking Technique
Authors: Ogura Katsuo
Published: July 2016

About 1300, 60 and 70 Herbig-Haro candidates have been picked up in the Ori A/L1641, Ori B/L1630 and NGC 2264/Mon OBI regions, respectively, on deep Schmidt plates. The contrast enhancement and unsharp masking technique has been applied simultaneously. Unsharp masking applied to an objective-prism Schmidt plate for the Carina Nebula region has yielded the detection of 38 Hα emission stars, of which 13 are new findings.
Measurement of Rose Indices on a Kiso 4-Degree Objective Prism Plate
Authors: Lee S.-G.
Published: July 2016

In order to check the utilisation of 4-degree objective prism spectra for the deep spectroscopic galactic structure study, Rose’s (1984) seven indices between 3500 Å and 4400 Å for 19 Hyades stars were measured on a Kiso Schmidt prism plate, L3496. By comparison with those of Rose (1984), it is found that his spectral indices, Hδ/FeI, Hγ/P(4325), and P(3912)/P(CN) measured on these low dispersion spectra, are still usable. This result gives good prospects for a deep spectroscopic galactic structure program with the 4-degree objective prism and narrow band interference filters.
A Deep Spectral Survey of Peculiar A-Type Stars
Authors: Kurtanidze Omar M. , Nikolashvili Miriam G.
Published: July 2016

We are conducting a long-term deep spectral survey to investigate the distribution of Ap and Am stars in selected fields of the Milky Way and in open star clusters of different ages. The spectral survey is based on objective prism spectra obtained with an eight degree prism attached to the 70/98 cm meniscus telescope (f/3, 135 Å mm−1at Hδ) at the Abastumani Observatory. Kodak IIIa-J emulsions hypersensitized by baking in nitrogen gas are used in combination with a 500 Å FWHM filter centered on Hδ. A limiting magnitude ofmB= 14 was reached in an exposure time of 120 m. Study of the objective prism plates is still in a very early stage. Observations of the central part of the same field taken with a CCD resulted in a limiting magnitudemB= 16. On the basis of spectral material obtained, a wide range of spectra may be classified in the MK system.
Studies of Extended Southern Galactic Clusters and Loose Star Groupings using the Bosscha Schmidt Telescope
Authors: Wiramihardja S. D. , Hidayat B. , Tejawijaya I. , Hakim  , Malasan L.
Published: July 2016

One of the programs conducted with the Bosscha Schmidt telescope is the study of loose star groupings and extended galactic clusters in the southern hemisphere (The 1963; Hidayat & Wiramihardja 1978; Hidayat et al. 1994). The aims of the study are, in short, to:

1.

investigate or to confirm the physical reality of the loose groupings.

2.

study the relationship between extended clusters or loose groupings with their environment.

3.

derive their physical parameters which ultimately can be used to construct the luminosity functions of the objects.

The purpose of the present paper is to present one of our results for the extended cluster OCL 1104-584 (NGC 3532). The results of studies of loosegrouping objects taken from the list of Loden (1979) will be presented elsewhere.
The Stellar Structure of the Orion Spiral ARM in Selected Directions. I. The Galactic Anticenter
Authors: Kvernadze Teimuraz M.
Published: July 2016

To investigate the spatial distribution of various stellar groups in the Hertzsprung-Russell diagram, it is necessary to have homogeneous observational data of MK spectral classification and photometry. This enables us to perform some statistical analyses with sufficient accuracy.

This paper reports BV photographic photometry of about 700 stars complete to mV = 12, in the direction of galactic anticenter with (l,b) = (169°, −12.4°), (178°, −2.4°), (184°, 8.9°). For the MK spectral data we used the catalogue by Bartaya and Kharadze (1992), which contains spectral and luminosity classes of 6042 stars in Kapteyn Areas Nos. 44–67. The observational data for this catalogue were obtained using the Abastumani Astrophysical Observatory 70 cm meniscus telescope and an 8°objective prism with dispersion 166 Åmm−1 near Hγ. The errors in classification are equal to ± 0.6 spectral subclasses and ± 0.5 luminosity classes, with a limiting magnitude of mV = 12.5.
Surveys for Hα Emission-Line Stars using the Bosscha Schmidt Telescope
Authors: Hidayat Bambang , Ogura Katsuo , Shinohara Masao
Published: July 2016

According to McCarthy (1984) the objects detected in objective prism surveys for Hα emission line are a ”most unnatural“ group. Of course they consist of many natural groupings whose identities or other peculiarities could become apparent after observing them with higher dispersion and resolution spectroscopy. In some cases, however, their galactic locations and associations with other known populations, can provide a clue to their population types.

The aims of the objective prism surveys using the Bosscha Schmidt telescope can be broadly categorised as follows:

1.

Searches for galactic planetary nebulae in the region 240° < l < 360 °; |b| ≤ 10°, initiated by The (1968).

2.

Searches for T-Tauri stars in some southern dark clouds (Shinohara, Ogura & Hidayat 1989).

3.

Searches for variations in Hα intensities and luminous emission stars in some selected galactic regions, such as in the Puppis and Carina regions.
The Study of Stellar Populations and Dynamics in the Small Magellanic Cloud using the UKST
Authors: Hatzidimitriou D.
Published: July 2016

The combination of the wide field of Schmidt telescope photographic plates with fast measuring machines such as COSMOS and APM, had a major impact on the study of the global properties of the Magellanic Clouds. Results (based on UKST data) regarding the stellar populations and dynamics of the Small Magellanic Cloud are described here in some detail. The stellar content and kinematics of the intercloud region are also outlined, with particular emphasis on the importance of this region in understanding the interaction between the Magellanic Clouds.
The UKST Survey of Planetary Nebulae in the Small Magellanic Cloud
Authors: Morgan D. H.
Published: July 2016

This paper describes the results of searches for planetary nebulae on seven objective prism plates which were taken with the UK 1.2m Schmidt Telescope and cover the entire Small Magellanic Cloud. A total of 62 objects were detected; their spatial distribution is discussed.
Multi-Wavelength Imaging of Galaxies – using Kiso Schmidt CCD Photometry
Authors: van Driel Wim
Published: July 2016

Equipping the 105 cm Kiso Observatory Schmidt telescope with large CCD cameras has initiated a new phase for galaxy photometry studies performed with the telescope. As part of multi-wavelength studies deep multi-colour CCD images were obtained of various types of individual galaxies, as well as pairs and groups of galaxies.
Conference Summary
Authors: Cannon Russell D.
Published: July 2016

At the conclusion of the meeting, Karel van der Hucht and Martin McCarthy S J shared the task of giving a comprehensive summary of all the papers presented. I thank them for making their extensive notes available to me. There were also a number of lively discussions on specific topics during the course of the week. Here I will attempt to set out the main conclusions that can be drawn from the papers and discussions, and to see the way forward for Schmidt telescope astronomy. Much of the following is based on the results of a questionnaire which was circulated by the Scientific Organising Committee towards the end of the meeting, with 28 responses received.
The Scanning Fabry-Perot Spectrometer
Authors: Atherton P D
Published: July 2016

In this review the development of the Scanning Fabry-Perot for use in Astronomy, from its invention to the present day is described. The limitation of angle scanning and pressure scanning led to the development of piezo scanned etalons incorporating capacitance micrometers to form a servo-controlled system.
Rotation Curves of 38 Galaxies in Clusters from Scanning Fabry-Perot observations
Authors: Amram P. , Marcelin M. , Balkowski C. , Boulesteix J. , Coarer E. le , Cayatte V. , Sullivan W.
Published: July 2016

A major astrophysical problem is related to the fact that rotation curves (RCs)) of galaxies are flat. The presence of a dark halo is most often invoked to explain that. Some controversies exist concerning the existence of a dark halo for galaxies in very hostile environments like in center of clusters. Using a scanning Fabry-Perot interferometer, we have observed Hα velocity fields of a sample of 38 galaxies located in 7 different clusters of galaxies. From this sample, our conclusion is that spirals located in the central part of clusters do not have decreasing RCs within the optical radius.