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2521. Spectroscopically identified CVs from LAMOST survey. I.
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.
2522. Spectroscopic analysis of EDisCS clusters
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.
2523. Spectroscopic analysis of 348 red giants
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.
2524. Spectroscopic analysis of RJHA 49 and SS73 21
ID:
ivo://CDS.VizieR/J/A+A/477/877
Title:
Spectroscopic analysis of RJHA 49 and SS73 21
Short Name:
J/A+A/477/877
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the spectra and the evolutionary stages of two peculiar emission-line stars: RJHA 49 and SS73 21. We used low and high resolution optical data. Line identifications and measurements were performed for several features in their spectra.
2525. Spectroscopic analysis of the CKS sample. I.
ID:
ivo://CDS.VizieR/J/ApJ/875/29
Title:
Spectroscopic analysis of the CKS sample. I.
Short Name:
J/ApJ/875/29
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from a quantitative spectroscopic analysis conducted on archival Keck/HIRES high-resolution spectra from the California-Kepler Survey (CKS) sample of transiting planetary host stars identified from the Kepler mission. The spectroscopic analysis was based on a carefully selected set of FeI and FeII lines, resulting in precise values for the stellar parameters of effective temperature (Teff) and surface gravity (logg). Combining the stellar parameters with Gaia DR2 parallaxes and precise distances, we derived both stellar and planetary radii for our sample, with a median internal uncertainty of 2.8% in the stellar radii and 3.7% in the planetary radii. An investigation into the distribution of planetary radii confirmed the bimodal nature of this distribution for the small-radius planets found in previous studies, with peaks at ~1.47+/-0.05 and ~2.72+/-0.10R_{Earth}_ with a gap at ~1.9R_{Earth}_. Previous studies that modeled planetary formation that is dominated by photoevaporation predicted this bimodal radii distribution and the presence of a radius gap, or photoevaporation valley. Our results are in overall agreement with these models, as well as core powered mass-loss models. The high internal precision achieved here in the derived planetary radii clearly reveal the presence of a slope in the photoevaporation valley for the CKS sample, indicating that the position of the radius gap decreases with orbital period; this decrease was fit by a power law of the form R_pl_{propto}P^-0.11^, which is consistent with both photoevaporation and core powered mass-loss models of planet formation, with Earth-like core compositions.
2526. Spectroscopic analysis of Tuc III stream
ID:
ivo://CDS.VizieR/J/ApJ/866/22
Title:
Spectroscopic analysis of Tuc III stream
Short Name:
J/ApJ/866/22
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a spectroscopic study of the tidal tails and core of the Milky Way satellite Tucana III, collectively referred to as the Tucana III stream, using the 2dF+AAOmega spectrograph on the Anglo-Australian Telescope and the IMACS spectrograph on the Magellan Baade Telescope. In addition to recovering the brightest nine previously known member stars in the Tucana III core, we identify 22 members in the tidal tails. We observe strong evidence for a velocity gradient of 8.0+/-0.4km/s/deg over at least 3{deg} on the sky. Based on the continuity in velocity, we confirm that the Tucana III tails are real tidal extensions of Tucana III. The large velocity gradient of the stream implies that Tucana III is likely on a radial orbit. We successfully obtain metallicities for four members in the core and 12 members in the tails. We find that members close to the ends of the stream tend to be more metal-poor than members in the core, indicating a possible metallicity gradient between the center of the progenitor halo and its edge. The spread in metallicity suggests that the progenitor of the Tucana III stream is likely a dwarf galaxy rather than a star cluster. Furthermore, we find that with the precise photometry of the Dark Energy Survey data, there is a discernible color offset between metal-rich disk stars and metal-poor stream members. This metallicity-dependent color offers a more efficient method to recognize metal-poor targets and will increase the selection efficiency of stream members for future spectroscopic follow-up programs on stellar streams.
2527. Spectroscopic and photometric properties of Tombaugh 1
ID:
ivo://CDS.VizieR/J/AJ/151/6
Title:
Spectroscopic and photometric properties of Tombaugh 1
Short Name:
J/AJ/151/6
Date:
21 Oct 2021
Publisher:
CDS
Description:
Open clusters can be the key to deepening our knowledge on various issues involving the structure and evolution of the Galactic disk and details of stellar evolution because a cluster's properties are applicable to all its members. However, the number of open clusters with detailed analysis from high-resolution spectroscopy or precision photometry imposes severe limitations on studies of these objects. To expand the number of open clusters with well-defined chemical abundances and fundamental parameters, we investigate the poorly studied, anticenter open cluster Tombaugh 1. Using precision uvbyCaH{beta} photometry and high-resolution spectroscopy, we derive the cluster's reddening, obtain photometric metallicity estimates, and, for the first time, present a detailed abundance analysis of 10 potential cluster stars (nine clump stars and one Cepheid). Using the radial position from the cluster center and multiple color indices, we have isolated a sample of unevolved, probable single-star members of Tombaugh 1. From 51 stars, the cluster reddening is found to be E(b-y)=0.221+/-0.006 or E(B-V)=0.303+/-0.008, where the errors refer to the internal standard errors of the mean. The weighted photometric metallicity from m_1_ and hk is [Fe/H]=-0.10+/-0.02, while a match to the Victoria-Regina Stromgren isochrones leads to an age of 0.95+/-0.10 Gyr and an apparent modulus of (m-M)=13.10+/-0.10. Radial velocities identify six giants as probable cluster members, and the elemental abundances of Fe, Na, Mg, Al, Si, Ca, Ti, Cr, Ni, Y, Ba, Ce, and Nd have been derived for both the cluster and the field stars. Tombaugh 1 appears to be a typical inner thin disk, intermediate-age open cluster of slightly subsolar metallicity, located just beyond the solar circle, with solar elemental abundance ratios except for the heavy s-process elements, which are a factor of two above solar. Its metallicity is consistent with a steep metallicity gradient in the galactocentric region between 9.5 and 12 kpc. Our study also shows that Cepheid XZ CMa is not a member of Tombaugh 1 and reveals that this Cepheid presents signs of barium enrichment, making it a probable binary star.
2528. Spectroscopic atlas of Deneb 3826-5212{AA}
ID:
ivo://CDS.VizieR/J/A+A/400/1043
Title:
Spectroscopic atlas of Deneb 3826-5212{AA}
Short Name:
J/A+A/400/1043
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a spectroscopic atlas of Deneb (A2 Iae) obtained with the long camera of the 1.22-m telescope of the Dominion Astrophysical Observatory using Reticon and CCD detectors. For {lambda}{lambda}3826-5212 the inverse dispersion is 2.4{AA}/mm with a resolution 0.072{AA}. At the continuum the mean signal-to-noise ratio is 1030. The wavelengths in the laboratory frame, the equivalent widths, and the identifications of the various spectral features are given. This atlas should provide useful guidance for studies of other stars with similar spectral types. The stellar and synthetic spectra with their corresponding line identifications can be examined at http://www.brandonu.ca/physics/gulliver/atlases.html .
2529. Spectroscopic atlas of o Per 3826-4882{AA}
ID:
ivo://CDS.VizieR/J/A+A/413/285
Title:
Spectroscopic atlas of o Per 3826-4882{AA}
Short Name:
J/A+A/413/285
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a spectroscopic atlas of the sharp-lined, hot metallic-line star o Pegasi (A1 IV) based on spectrograms obtained with the long camera of the 1.22-m telescope of the Dominion Astrophysical Observatory using a Reticon detector. For 3826-4882 the inverse dispersion is 2.4{AA}/mm with a resolution of 0.072{AA}. At the continuum the mean signal-to-noise ratio is 800. The wavelengths in the laboratory frame, the equivalent widths, and the identifications of the various spectral features are given. The stellar and synthetic spectra with their corresponding line identifications can be examined at http://www.brandonu.ca/physics/gulliver/atlases.html .
2530. Spectroscopic catalog in 24 clusters
ID:
ivo://CDS.VizieR/J/ApJS/188/280
Title:
Spectroscopic catalog in 24 clusters
Short Name:
J/ApJS/188/280
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a spectroscopic catalog of (mostly) red galaxies in 24 galaxy clusters in the redshift range 0.17<z<0.92 obtained with the LRIS instrument on the Keck I telescope. Here we describe the observations and the galaxy spectra, including the discovery of three cD galaxies with LINER emission spectra, and the spectroscopic discovery of four new galaxy-galaxy lenses in cluster environments. All but two of the galaxy clusters observed as part of this experiment were previously known.

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