- ID:
- ivo://CDS.VizieR/J/ApJS/239/3
- Title:
- Spectroscopic accuracy for B-like ions with Z=24-30
- Short Name:
- J/ApJS/239/3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report calculations of spectroscopic accuracy for 513 states in the B-like ions with Z=24-30. The energy levels and transition rates are calculated using the second-order many-body perturbation theory, while multiconfiguration Dirac-Hartree-Fock calculations are performed to support the former results. The present two sets of results agree excellently with each other, and can be used as benchmarks in the future. The electron-impact excitation (EIE) collision strengths are calculated based on independent processes and isolated resonances approximation using the distorted wave method. Based on the present atomic data, the spectral lines of these ions are simulated using a collisional radiative model. The amount of energy, transition data, and EIE collision strengths of high accuracy are significantly increased for several B-like ions of astrophysical interest, where experimental data are still very scarce. The results can be used in line identification, plasma modeling, and diagnostics of astrophysical plasmas.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/159/43
- Title:
- Spectroscopically identified CVs from LAMOST survey. I.
- Short Name:
- J/AJ/159/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A sample of cataclysmic variables (CVs) is presented including spectroscopically identified 380 spectra of 245 objects, of which 58 CV candidates are new discoveries. The BaggingTopPush and the Random Forest algorithms are applied to the Fifth Data Release (DR5) of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) to retrieve CVs with strong emission lines and with broad absorption lines respectively. Based on spectroscopic classification, 134 dwarf novae, 41 nova-like variables, and 19 magnetic CVs are identified from the sample. In addition, 89 high-inclination systems and 33 CVs showing companion stars are recognized and discussed for their distinct spectral characteristics. Comparisons between CVs from LAMOST and from published catalogs are made in spatial and magnitude distribution, and the difference of their locus in the Gaia color-absolute magnitude diagram (CaMD) are also investigated. More interestingly, for two dwarf novae observed through LAMOST and SDSS in different epochs, their spectra both in quiescence phase and during outburst are exhibited.
- ID:
- ivo://CDS.VizieR/III/137
- Title:
- Spectroscopically Identified Hot Subdwarf Stars
- Short Name:
- III/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog contains data for 1225 spectroscopically classified hot subdwarf stars. It excludes central stars of planetary nebulae but includes stars in binary systems. The data assembled include, where available, alternative designations, accurate coordinates, UBV and uvby photometry, spectral types and determinations of effective temperature and surface gravity.
- ID:
- ivo://CDS.VizieR/B/wd
- Title:
- Spectroscopically identified white dwarfs
- Short Name:
- B/wd
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is an update of the Villanova catalog published in the ApJS paper, corresponding to the Web version of the catalog in Apr 2014 (see http://www.astronomy.villanova.edu/WDCatalog/index.html). The introduction to the 1999 catalog is in the file "preface.tex". This updated version lists 14294 unique white dwarfs for a total of 27975 rows (multiple observations).
- ID:
- ivo://CDS.VizieR/III/210
- Title:
- Spectroscopically Identified White Dwarfs
- Short Name:
- III/210
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A catalog of 2249 white dwarfs which have been identified spectroscopically is presented complete through 1996 April. This compilation is the fourth edition of the Villanova Catalog of Spectroscopically Identified White Dwarfs. For each degenerate star, the following data entries with references are provided: (1) catalog coordinate designation or WD number, in order of right ascension; (2) the right ascension and declination for epoch 1950.0; (3) the spectral type based upon the new system; (4) a catalog symbol denoting binary membership; (5) a list of most names known to exist for a given star; (6) proper motion and position angle; (7) broad-band UBV Photometry, V, B-V, U-B; (8) multichannel spectrophotometry, V(MC), g-r; (9) Stroemgren narrow-band photometry y, b-y, u-b; (10) an absolute visual magnitude based upon the best available color-magnitude calibration or trigonometric parallax; (11) the observed radial velocity uncorrected for gravitational redshift or solar motion; and (12) the trigonometric parallax with mean error when available. A Notes section for unusual or peculiar stars and a coded Reference Key alphabetized by the first author's last name are presented, as well as an expanded table cross-referencing all names to catalog WD number. An introduction and full descriptions of the entries are provided in the text.
- ID:
- ivo://CDS.VizieR/III/235B
- Title:
- Spectroscopically Identified White Dwarfs
- Short Name:
- III/235B
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is an update of the Villanova catalog published in the ApJS paper, corresponding to the Web version of the catalog in August 2006 (see http://www.astronomy.villanova.edu/WDCatalog/index.html). The introduction to the 1999 catalog is in the file "preface.tex". This version includes many additions and corrections to the original 4th edition: additional entries (555 newly discovered white dwarfs), additional data for previously known white dwarfs (marked in the catalog); new SDSS photometry has also been added. The total number of white dwarfs in this version is 5557.
- ID:
- ivo://CDS.VizieR/III/129
- Title:
- Spectroscopically Identified White Dwarfs
- Short Name:
- III/129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This compilation is an expanded and updated version to the second edition of the catalogue (Mc Cook and Sion 1984); it includes 1282 stars. Please refer to the introduction by the authors (file "intro.txt"), to the documentation of the computer-readable version by W.H. Warren (file "adc.txt" or "adc.tex"), and to the original paper for an extensive description.
- ID:
- ivo://CDS.VizieR/V/65
- Title:
- Spectroscopically Selected Halo K Giants
- Short Name:
- V/65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog results from a survey for distant Field K giants in the Galactic halo made for purposes of locating a chemically and kinematically unbiased sample out to about 25 kpc from the Sun. The motivation for the study and sample selection are outlined by Ratnatunga & Freeman (1985ApJ...291..260R), while details and analysis of the results will be found in Ratnatunga & Freeman (1989). Three high-galactic latitude fields each of 20 square degrees, designated by their Selected-Area identifications, include the following: SA 141 (l=240,b=-85); SA 189 (277, -50); and SA 127 (272, +38), and have the apparent magnitude range 13 < V < 16 and color range (B-V) > 0.9. Stars were selected from PDS photographic photometry of Schmidt plates (see Ratnatunga 1983, catalog II/121). K-giant selection used the Mgb+MgH feature at 5100A from digital image analysis of PDS scans of ESO 1-m Schmidt telescope objective-prism spectra with 450 A/mm at H-gamma resolution on IIIa-J plates exposed through a Schott GG475 filter. Luminosity confirmation, line-of-sight velocities, and metallicity were determined from 2-A resolution slit spectra taken with the 4-m Anglo- Australian and 1.9-m Mount Stromlo telescopes. Cross identifications exist for some stars in the SA 141 SGP field only.
- ID:
- ivo://CDS.VizieR/J/ApJ/850/181
- Title:
- Spectroscopic analysis of EDisCS clusters
- Short Name:
- J/ApJ/850/181
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A major question in galaxy formation is how the gas supply that fuels activity in galaxies is modulated by their environment. We use spectroscopy of a set of well-characterized clusters and groups at 0.4<z<0.8 from the ESO Distant Cluster Survey and compare it to identically selected field galaxies. Our spectroscopy allows us to isolate galaxies that are dominated by old stellar populations. Here we study a stellar-mass-limited sample (log(M*/M_{sun}_)>10.4) of these old galaxies with weak [OII] emission. We use line ratios and compare to studies of local early-type galaxies to conclude that this gas is likely excited by post-AGB stars and hence represents a diffuse gas component in the galaxies. For cluster and group galaxies the fraction with EW([OII])>5{AA} is f[OII]=0.08_-0.02_^+0.03^ and f[OII]=0.06_-0.04_^+0.07^, respectively. For field galaxies we find f[OII]=0.27_-0.06_^+0.07^, representing a 2.8{sigma} difference between the [OII] fractions for old galaxies between the different environments. We conclude that a population of old galaxies in all environments has ionized gas that likely stems from stellar mass loss. In the field galaxies also experience gas accretion from the cosmic web, and in groups and clusters these galaxies have had their gas accretion shut off by their environment. Additionally, galaxies with emission preferentially avoid the virialized region of the cluster in position-velocity space. We discuss the implications of our results, among which is that gas accretion shutoff is likely effective at group halo masses (logM/M_{sun}_>12.8) and that there are likely multiple gas removal processes happening in dense environments.
- ID:
- ivo://CDS.VizieR/J/A+A/547/A91
- Title:
- Spectroscopic analysis of 348 red giants
- Short Name:
- J/A+A/547/A91
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present basic atmospheric parameters (Teff, logg, vt, and [Fe/H]) as well as luminosities, masses, radii, and absolute radial velocities for 348 stars, presumably giants, from the ~1000 star sample observed within the Penn State-Torun Centre for Astronomy Planet Search (PTPS) with the High Resolution Spectrograph of the 9.2m Hobby-Eberly Telescope. The stellar parameters (luminosities, masses, radii) are key to properly interpreting newly discovered low-mass companions, while a systematic study of the complete sample will create a basis for future statistical considerations concerning the appearance of low-mass companions around evolved low- and intermediate-mass stars.