adsabs/AstroCLIMB huggingface dataset:
Paper: Can Supernovae from Runaway Stars Mimic the Signs of Absorbing “Supervirial” Gas?
Authors: Mukesh Singh Bisht, Projjwal Banerjee, Biman B. Nath, Yuri Shchekinov
Figure caption: Column density of ions as a function of time for three lines of sight. The top (a), middle (b), and bottom (c) panels show the column density toward Mrk 421 (S. Das et al. 2021), IES 1553+13 (S. Das et al. 2019b), and NGC 3783 (R. L. McClain et al. 2024) respectively. The magenta, green, and blue bands show the column density range of O VIII, Ne X, and Si XIV, respectively, calculated from our model. The dashed lines in the same color show the upper and lower limit of the observed column density of respective ions.
Paper: Can Supernovae from Runaway Stars Mimic the Signs of Absorbing “Supervirial” Gas?
Authors: Mukesh Singh Bisht, Projjwal Banerjee, Biman B. Nath, Yuri Shchekinov
Figure caption: The final position of 1000 runaway massive stars where they explode as core-collapse supernovae: (a) latitude b vs. distance d from the Sun, (b) Height z from the Galactic plane vs. d, and (c) z vs. b.
Paper: Can Supernovae from Runaway Stars Mimic the Signs of Absorbing “Supervirial” Gas?
Authors: Mukesh Singh Bisht, Projjwal Banerjee, Biman B. Nath, Yuri Shchekinov
Figure caption: Ionization of an oxygen gas at T = 5 keV with an initial O I abundance of 0.001 cm−3 and initial n  e  = 10−5 cm−3.
Paper: An Image-based Search for Pulsar Candidates in the MeerKAT Bulge Survey
Authors: Dale A. Frail, Emil Polisensky, Scott D. Hyman, William D. Cotton, Namir E. Kassim, Michele L. Silverstein, Rahul Sengar, David L. Kaplan, Francesca Calore, Joanna Berteaud, Maïca Clavel, Marisa Geyer, Samuel Legodi, Vasaant Krishnan, Sarah Buchner, Fernando Camilo
Figure caption: Polarized sources (red) and known pulsars (blue). The left panel plots the absolute value of the circular polarization fraction vs. Stokes I flux density, while the right panel plots the linear polarization vs. Stokes I flux density. The size of the circle for each point is proportional to the spectral index, with larger circles indicating steeper negative spectral indices. Gray points are polarization and flux density values taken from the compilation of S. Johnston & M. Kerr (2018).
Paper: An Image-based Search for Pulsar Candidates in the MeerKAT Bulge Survey
Authors: Dale A. Frail, Emil Polisensky, Scott D. Hyman, William D. Cotton, Namir E. Kassim, Michele L. Silverstein, Rahul Sengar, David L. Kaplan, Francesca Calore, Joanna Berteaud, Maïca Clavel, Marisa Geyer, Samuel Legodi, Vasaant Krishnan, Sarah Buchner, Fernando Camilo
Figure caption: Polarized flux fraction distribution for 353 circularly polarized sources. Filled stars indicate known pulsars. Open circles are identified as image artifacts in Section 5.2 and not included in the upper histogram plot.
Paper: An Image-based Search for Pulsar Candidates in the MeerKAT Bulge Survey
Authors: Dale A. Frail, Emil Polisensky, Scott D. Hyman, William D. Cotton, Namir E. Kassim, Michele L. Silverstein, Rahul Sengar, David L. Kaplan, Francesca Calore, Joanna Berteaud, Maïca Clavel, Marisa Geyer, Samuel Legodi, Vasaant Krishnan, Sarah Buchner, Fernando Camilo
Figure caption: The difference in source spectral index derived using the two half-band-averaged images and the individual 12 subband images for 85,273 compact, single-component sources. Sources are colored according to their S/N in the full-band image.
Paper: An Image-based Search for Pulsar Candidates in the MeerKAT Bulge Survey
Authors: Dale A. Frail, Emil Polisensky, Scott D. Hyman, William D. Cotton, Namir E. Kassim, Michele L. Silverstein, Rahul Sengar, David L. Kaplan, Francesca Calore, Joanna Berteaud, Maïca Clavel, Marisa Geyer, Samuel Legodi, Vasaant Krishnan, Sarah Buchner, Fernando Camilo
Figure caption: Angular offsets in R.A. and decl. for 6766 unresolved sources detected in both this survey and the RACS-mid, after applying astrometric corrections. See Section 4.1 for details.
Paper: An Image-based Search for Pulsar Candidates in the MeerKAT Bulge Survey
Authors: Dale A. Frail, Emil Polisensky, Scott D. Hyman, William D. Cotton, Namir E. Kassim, Michele L. Silverstein, Rahul Sengar, David L. Kaplan, Francesca Calore, Joanna Berteaud, Maïca Clavel, Marisa Geyer, Samuel Legodi, Vasaant Krishnan, Sarah Buchner, Fernando Camilo
Figure caption: A typical 3.°125 × 3.°125 mosaic field for one of the 20 pointings. These are Stokes I (left) and Stokes V (right) images for the G0.0+5.5 mosaic field. There are approximately 25,000 radio continuum sources. After eliminating image artifacts and other false positives (see Section 5), we identify four known pulsars and seven circularly polarized sources but no linearly polarized sources in this mosaic field.
Paper: An Image-based Search for Pulsar Candidates in the MeerKAT Bulge Survey
Authors: Dale A. Frail, Emil Polisensky, Scott D. Hyman, William D. Cotton, Namir E. Kassim, Michele L. Silverstein, Rahul Sengar, David L. Kaplan, Francesca Calore, Joanna Berteaud, Maïca Clavel, Marisa Geyer, Samuel Legodi, Vasaant Krishnan, Sarah Buchner, Fernando Camilo
Figure caption: Galactic distribution of the 20 mosaic pointings used in this survey. Each square is 3.°125 × 3.°125 in size. The full survey is symmetric about the GC and covers a vertical strip ±20° in latitude and at least ±1.°5 in longitude, but it widens to ±4.°5 at lower latitudes. The positions of the known pulsars that lie within the survey area are indicated by filled circles.
Paper: A Two-zone Accretion Disk in the Changing-look Active Galactic Nucleus 1ES 1927+654: Physical Implications for Tidal Disruption Events and Super-Eddington Accretion
Authors: Ruancun Li, Luis C. Ho, Claudio Ricci, Benny Trakhtenbrot
Figure caption: The ﹩\dot{m}-{\rm{\Sigma }}﹩                      S-curve (left) and flux reduction factor (right) with different values of the viscosity parameter (α). The black error bars indicate the ﹩\dot{m}﹩ and Σ derived from our fiducial choice α = 0.1 (Table 2), and the black dashed line represents the slim disk branch ﹩\dot{m}\propto {\rm{\Sigma }}﹩, while the black dotted line represents the radiation-pressure-dominated thin disk branch ﹩\dot{m}\propto {{\rm{\Sigma }}}^{-1}﹩. The colored points of ﹩\dot{m}﹩ and Σ are calculated from the same equation set in Section 2.1 but with different values of α: 0.01 (red), 0.03 (blue), and 0.06 (green). The two branches in the left panel are also shifted accordingly. The right panel shows the flux reduction factor (χ), defined in Section 3.3, as a function of radius, the same as in Figure 6 with i = 0°. Solid lines assume the ﹩\bar{\rho }﹩ and T profile for a radiatively cooled accretion flow (thin disk), while dotted lines pertain to an optically thick ADAF (slim disk). Colors represent different α: 0.01 (red), 0.03 (blue), 0.06 (green), and 0.1 (black).
Paper: A Closer Look at Dwarf Galaxies Exhibiting Mid-infrared Variability: Active Galactic Nuclei Confirmation and Comparison With Nonvariable Dwarf Galaxies
Authors: Archana Aravindan, Gabriela Canalizo, Nathan Secrest, Shobita Satyapal, Thomas Bohn
Figure caption: Optical BPT and VO diagrams showing the positions of the variable targets observed with NIRES (blue) and the variable galaxies not observed with NIRES (cyan). The emission-line ratios were derived from fluxes obtained from the SDSS MPA-JHU catalog. Most of the observed variable targets lie primarily in the SF regions, and there is no indicator of AGN activity based on these diagnostic diagrams.
Paper: A Closer Look at Dwarf Galaxies Exhibiting Mid-infrared Variability: Active Galactic Nuclei Confirmation and Comparison With Nonvariable Dwarf Galaxies
Authors: Archana Aravindan, Gabriela Canalizo, Nathan Secrest, Shobita Satyapal, Thomas Bohn
Figure caption: WISE light curves of J1205, one of the variable dwarf galaxies identified in this work, in different WISE bands W1 (3.4 μm), W2 (4.6 μm), and the change in color is depicted by W1–W2. The single-epoch photometry of the light curve is given by the gray points, while the blue points and the error bars represent the weighted mean and the standard error per 10 days observing period. The subtle redder-when-brighter behavior, consistent with the brightening being due to increasing AGN dominance over the host galaxy, and the gradual nature of the light curves indicate that the variability is likely due to AGN.
Paper: A Closer Look at Dwarf Galaxies Exhibiting Mid-infrared Variability: Active Galactic Nuclei Confirmation and Comparison With Nonvariable Dwarf Galaxies
Authors: Archana Aravindan, Gabriela Canalizo, Nathan Secrest, Shobita Satyapal, Thomas Bohn
Figure caption: Plot of [Si VI] vs. W2 flux for the [Si VI] nondetections in our sample. The solid line indicating the correlation is from J. M. Cann et al. (2021), which was derived from observations from F. Müller-Sánchez et al. (2018), and the shaded region indicates the scatter in the data. The targets are marked as J0847 (1), J0928 (2), J1032 (3), J1144 (4), J1205 (5), J1320 (6), J1358 (7), J1428 (8), J1612 (9). Targets whose upper limits are above the relation would require deeper observations in order to detect the [Si VI] line, while for the targets with upper limits below the relation, it is likely that the [Si VI] line is not present. For more details regarding the upper limits, refer to the Appendix.
Paper: A Two-zone Accretion Disk in the Changing-look Active Galactic Nucleus 1ES 1927+654: Physical Implications for Tidal Disruption Events and Super-Eddington Accretion
Authors: Ruancun Li, Luis C. Ho, Claudio Ricci, Benny Trakhtenbrot
Figure caption: Cartoon to illustrate the characteristic scales of the accretion disk discussed in Section 5.6 and their relation to BH mass (M BH) and dimensionless mass accretion rate (﹩\dot{m}﹩). The black circle depicts the BH, exterior to which is an outer thin truncated disk (red), an inner puffed-up overheated disk (green when Compton cooling is dominant but otherwise orange for low M BH and high ﹩\dot{m}﹩), and an X-ray corona (blue). As M BH increases, the truncation radius (R tr) decreases but the radius of the corona (R cor) remains constant (Equation (31)). By contrast, for 1ES 1927+654 and normal type 1 AGNs such as Mrk 335 and I Zwicky 1, R tr increases while R cor generally decreases with increasing ﹩\dot{m}﹩.
Paper: A Closer Look at Dwarf Galaxies Exhibiting Mid-infrared Variability: Active Galactic Nuclei Confirmation and Comparison With Nonvariable Dwarf Galaxies
Authors: Archana Aravindan, Gabriela Canalizo, Nathan Secrest, Shobita Satyapal, Thomas Bohn
Figure caption: (a) NIR spectrum of J1205 in order 5 of NIRES, shifted to rest-frame wavelength. The blue-dashed line indicates the coronal line [S IX] detected at a 5σ level. The gray-shaded area represents the region of significant telluric absorption. (b) The zoomed-in spectrum with spectral fits to the [S IX] (1.252 μm) line and the [Fe II] (1.257 μm) line. The lower panel depicts the residuals to the fit, with the 1σ error in the spectrum shaded in gray around the dashed line indicating 0. The σ residuals indicates the standard deviation of the residuals determined by subtracting the fit to the spectrum from the data.
Paper: A Closer Look at Dwarf Galaxies Exhibiting Mid-infrared Variability: Active Galactic Nuclei Confirmation and Comparison With Nonvariable Dwarf Galaxies
Authors: Archana Aravindan, Gabriela Canalizo, Nathan Secrest, Shobita Satyapal, Thomas Bohn
Figure caption: Broad-line fits to the Paα line in two variable targets, J0928 (a) and J1144 (b), which could indicate a broad component from the BLR of the galaxies. There was an unidentified line next to He I line at 1.869 μm, which was fit but left unmarked. The lower panels in both figures depict the residuals to the fit, with the 1σ error from the noise in the spectrum shaded in gray around the dashed line indicating 0.
Paper: A Closer Look at Dwarf Galaxies Exhibiting Mid-infrared Variability: Active Galactic Nuclei Confirmation and Comparison With Nonvariable Dwarf Galaxies
Authors: Archana Aravindan, Gabriela Canalizo, Nathan Secrest, Shobita Satyapal, Thomas Bohn
Figure caption: Keck/NIRES spectrum of J1205 in the wavelength region around [Si VI]. The small emission feature found at the wavelength of [Si VI] (indicated by the dashed blue line) has a flux compatible with the expected flux for [Si VI], however, it is below the 3σ detection limit and may not be real.
Paper: On the Origin of the 107 K Hot Emitting Gas in the Circumgalactic Medium of the Milky Way
Authors: Mukesh Singh Bisht, Biman B. Nath, Smita Mathur
Figure caption: This figure shows the results of the MCMC analysis. The left and right panel shows the corner plot of parameters for virial and SV phases respectively. The three vertical dashed black lines in the 1D histogram mark the 16th, 50th, and 84th percentiles of the samples. The three contour levels plotted with black solid lines contain 32%, 64%, and 96% of the samples, respectively. The blue line shows the initial guess value and is visible only in the case of z v, as the guess values for other parameters are out of the plot ranges. The values on the top of each 1D histogram show the 50th percentile value (median) and the error shown corresponds to 16th and 84th percentiles, which is equal to a 1σ error if the resulting 1D histogram is Gaussian, which is the case for most of the parameters. We performed the analysis using 32 walkers and 50,000 steps with Gaussian priors for all the parameters. We ensured the convergence of samples as the total number of steps are larger than 50 times the autocorrelation time. Note that the width in the Gaussian prior (see Table 1) is sufficiently larger than the width in the resulting histogram of the respective parameters. This shows that the resulting values are well constrained.
Paper: On the Origin of the 107 K Hot Emitting Gas in the Circumgalactic Medium of the Milky Way
Authors: Mukesh Singh Bisht, Biman B. Nath, Smita Mathur
Figure caption: The correlation between the EM of the virial temperature gas and the EM of the SV temperature gas based on our models overplotted on observed EM. The black open circles show the EM correlation for the virial halo profile and SV gas in the extraplanar region. The blue circles show the EM correlation with the extraplanar virial and SV gas. The circles in cyan correspond to the virial gas in the halo + the virial gas and the SV gas in the extraplanar regions around the Galactic disk. The EM values from our model are plotted for the observed lines of sight. The observational data points from various authors are shown in other colors with error bars. All the observed EM values are rescaled to the metallicity of 0.3 solar for virial gas and solar for SV gas. The narrow range in the black points compared to cyan points along the X-axis shows the importance of having a “disk-shaped” virial phase profile.
Paper: On the Origin of the 107 K Hot Emitting Gas in the Circumgalactic Medium of the Milky Way
Authors: Mukesh Singh Bisht, Biman B. Nath, Smita Mathur
Figure caption: The EM data from various authors (A. Gupta et al. 2021; J. Bluem et al. 2022; G. Ponti et al. 2023; J. Bhattacharyya et al. 2023 and A. Gupta et al. 2023) is plotted as a function of sin (b), where b is the Galactic latitude. The figure contains two sets of data. The top set of points, with EM ≈ 10−3−10−1 cm−6 pc, corresponds to the virial phase, while lower data points with EM ≈ 10−5−10−3 cm−6 pc correspond to the SV phase. The solid black lines show the mean EM calculated in a bin size of ﹩{\rm{\Delta }}\sin (b)=0.1﹩ for both the virial and SV data sets. Note the anticorrelation between EM and sin (b) for both the virial and SV phases, as can be seen by the trend in the black solid lines.
Paper: On the Origin of the 107 K Hot Emitting Gas in the Circumgalactic Medium of the Milky Way
Authors: Mukesh Singh Bisht, Biman B. Nath, Smita Mathur
Figure caption: The initial temperature, density, and pressure maps. There are temperature and density gradients in both the R- and z-directions, as a result of the hydrostatic equilibrium in which the gravitational force is balanced by gas pressure combined with the rotation of the gas.
Paper: On the Origin of the 107 K Hot Emitting Gas in the Circumgalactic Medium of the Milky Way
Authors: Mukesh Singh Bisht, Biman B. Nath, Smita Mathur
Figure caption: Temperature maps at three epochs, at 5, 10, and 15 Myr, from left to right. As the energy is injected into the disk, the hot SV temperature gas is pushed up, generating an extraplanar region (shown in blue). Above this region, a virial temperature extraplanar region is formed (shown in yellow-green). Shock heating of the halo gas leads to another hot region at higher z (shown in light green).
Paper: On the Origin of the 107 K Hot Emitting Gas in the Circumgalactic Medium of the Milky Way
Authors: Mukesh Singh Bisht, Biman B. Nath, Smita Mathur
Figure caption: This figure shows the simulation results at 15 Myr. The top-left and right panels show the temperature and particle number density maps, respectively. The bottom-left and right panels show the pressure and metallicity maps, respectively.
Paper: On the Origin of the 107 K Hot Emitting Gas in the Circumgalactic Medium of the Milky Way
Authors: Mukesh Singh Bisht, Biman B. Nath, Smita Mathur
Figure caption: The cartoon representation of the structure of the gaseous components of the MW. The blue region in the center shows the ISM. The magenta and the yellow regions show the extent of the SV and virial temperature-emitting disks, respectively. The extended region in green shows the Galactic-virialized halo. Note that the size of different regions is not to scale; it simply represents the overall structure of the extraplanar gas around the MW.
Paper: An Image-based Search for Pulsar Candidates in the MeerKAT Bulge Survey
Authors: Dale A. Frail, Emil Polisensky, Scott D. Hyman, William D. Cotton, Namir E. Kassim, Michele L. Silverstein, Rahul Sengar, David L. Kaplan, Francesca Calore, Joanna Berteaud, Maïca Clavel, Marisa Geyer, Samuel Legodi, Vasaant Krishnan, Sarah Buchner, Fernando Camilo
Figure caption: Left: circular polarization and spectral properties of known pulsars (blue circles) and stars (green squares) identified in Tables 2 and 3. Gray points are taken from the compilation of circular polarization and spectral index values of S. Johnston & M. Kerr (2018) and F. Jankowski et al. (2018). Right: polarization (circular and linear) vs. spectral Index for pulsar candidates (red) identified in Table 6. Filled (open) circles represent candidates that lie inside (outside) the known pulsar distribution. The light-gray points are the same as the adjacent plot.
Paper: An Image-based Search for Pulsar Candidates in the MeerKAT Bulge Survey
Authors: Dale A. Frail, Emil Polisensky, Scott D. Hyman, William D. Cotton, Namir E. Kassim, Michele L. Silverstein, Rahul Sengar, David L. Kaplan, Francesca Calore, Joanna Berteaud, Maïca Clavel, Marisa Geyer, Samuel Legodi, Vasaant Krishnan, Sarah Buchner, Fernando Camilo
Figure caption: Top: spectrum of pulsar J1804−2858. Purple stars plot peak intensities from the TGSS (150 MHz, H. T. Intema et al. 2017), VLITE (340 MHz, T. E. Clarke et al. 2016), RACS-low (888 MHz, C. L. Hale et al. 2021), and RACS-mid (1368 MHz, S. W. Duchesne et al. 2023) catalogs. Blue circles, red triangles, and green squares show flux measurements from the MeerKAT half-band, quarter-band, and subband images. The corresponding in-band spectral fits (dashed lines) show excellent agreement both in-band and with the other radio catalogs. Bottom: spectrum of the polarized source J181521.88−325302.1 exhibiting variability. Catalog values are from RACS-low, RACS-mid, NVSS (1.4 GHz, J. J. Condon et al. 1998), and the first two VLASS epochs (3 GHz, M. Lacy et al. 2020).
Paper: Variable Ionized Disk Winds in MAXI J1803−298 Revealed by NICER
Authors: Zuobin Zhang, Cosimo Bambi, Honghui Liu, Jiachen Jiang, Fangzheng Shi, Yuexin Zhang, Andrew J. Young, John A. Tomsick, Benjamin M. Coughenour, Menglei Zhou
Figure caption: HID for the 2021 outburst of MAXI J1803−298 as seen by NICER (gray pentagons). The hardness is defined as the ratio between count rates in the 6–10 and 2–6 keV bands. We use colorful points to mark the spectroscopic epochs analyzed in this draft. Ten epochs cover the transition process from the hard state to the soft state. Epoch 1 is identified as hard state, Epochs 2–4 as intermediate state, and Epochs 5–10 as soft state.
Paper: An Image-based Search for Pulsar Candidates in the MeerKAT Bulge Survey
Authors: Dale A. Frail, Emil Polisensky, Scott D. Hyman, William D. Cotton, Namir E. Kassim, Michele L. Silverstein, Rahul Sengar, David L. Kaplan, Francesca Calore, Joanna Berteaud, Maïca Clavel, Marisa Geyer, Samuel Legodi, Vasaant Krishnan, Sarah Buchner, Fernando Camilo
Figure caption: Stokes I (left) and Stokes V (right) cutout images centered on our circularly polarized source J175306.50−285126.2 (red circle). We show the error circles for the Fermi source 4FGL J1753.2−2848 and the known pulsar PSR J1753−28. A possible association is suggested but not proven between our polarized radio source, the known pulsar, and the gamma-ray source.
Paper: An Image-based Search for Pulsar Candidates in the MeerKAT Bulge Survey
Authors: Dale A. Frail, Emil Polisensky, Scott D. Hyman, William D. Cotton, Namir E. Kassim, Michele L. Silverstein, Rahul Sengar, David L. Kaplan, Francesca Calore, Joanna Berteaud, Maïca Clavel, Marisa Geyer, Samuel Legodi, Vasaant Krishnan, Sarah Buchner, Fernando Camilo
Figure caption: Galactic distribution of the known pulsars in the mosaic fields (light-gray circles) vs. our final 30 pulsar candidates (red circles).
Paper: Variable Ionized Disk Winds in MAXI J1803−298 Revealed by NICER
Authors: Zuobin Zhang, Cosimo Bambi, Honghui Liu, Jiachen Jiang, Fangzheng Shi, Yuexin Zhang, Andrew J. Young, John A. Tomsick, Benjamin M. Coughenour, Menglei Zhou
Figure caption: Residuals to the model: Tbabs × (diskbb + nthcomp + Gauss) with three additional emission Gaussian lines for the calibration issues in the 2.0–3.0 keV band. Data are rebinned for visual clarity. The two vertical gray lines mark the positions of absorption by Fe XXV Lyα and Fe XXVI Lyα in the rest frame.
Paper: Variable Ionized Disk Winds in MAXI J1803−298 Revealed by NICER
Authors: Zuobin Zhang, Cosimo Bambi, Honghui Liu, Jiachen Jiang, Fangzheng Shi, Yuexin Zhang, Andrew J. Young, John A. Tomsick, Benjamin M. Coughenour, Menglei Zhou
Figure caption:                       ﹩\mathrm{log}\xi ﹩ vs. unabsorbed luminosity in the 1.0–10.0 keV band. The parameters are obtained from the XSTAR fit for Epochs 2–10. A slow change of physical properties of the X-ray wind is suggested during intermediate to soft state transitions.
Paper: Variable Ionized Disk Winds in MAXI J1803−298 Revealed by NICER
Authors: Zuobin Zhang, Cosimo Bambi, Honghui Liu, Jiachen Jiang, Fangzheng Shi, Yuexin Zhang, Andrew J. Young, John A. Tomsick, Benjamin M. Coughenour, Menglei Zhou
Figure caption: The unfolded spectra of Epochs 1–10. It is clearly shown that the disk wind features evolve with the continuum spectrum profile and flux. Data are rebinned for visual clarity.
Paper: Can Supernovae from Runaway Stars Mimic the Signs of Absorbing “Supervirial” Gas?
Authors: Mukesh Singh Bisht, Projjwal Banerjee, Biman B. Nath, Yuri Shchekinov
Figure caption: This figure shows the ratio of ”minimum” radiative cooling, recombination, and ionization timescale to the dynamical time as a function of time. The ”minimum” timescale corresponds to the mass shell, which has minimum radiative cooling/ionization/recombination time within M/M ej ≤ 0.2 and T ≥ 4 × 106 K. The green line shows the ratio of radiative cooling to dynamical time calculated using the cooling function for core composition with CLOUDY (G. J. Ferland et al. 2017). The magenta and cyan lines show the ratio of the recombination timescale (D. A. Verner & G. J. Ferland 1996) to the dynamical timescale for O VII and O VIII, respectively. The purple and red lines show the ratio of the ionization timescale (G. S. Voronov 1997) to the dynamical time for O VI and O VII, respectively. The above timescales are plotted for E = 1051 erg, M ej = 10 M ⊙, n 0 = 0.1cm−3 and β = 0.3.