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14181. Spectroscopy of Cepheids. l=30-250{deg}
ID:
ivo://CDS.VizieR/J/AJ/142/136
Title:
Spectroscopy of Cepheids. l=30-250{deg}
Short Name:
J/AJ/142/136
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper reports on the spectroscopic investigation of 238 Cepheids in the northern sky. Of these stars, about 150 are new to the study of the galactic abundance gradient. These new Cepheids bring the total number of Cepheids involved in abundance distribution studies to over 400. In this work, we also consider systematics between various studies and also those which result from the choice of models.
14182. Spectroscopy of classical Be stars
ID:
ivo://CDS.VizieR/J/other/BASI/39.517
Title:
Spectroscopy of classical Be stars
Short Name:
J/other/BASI/39.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a spectroscopic study of 150 Classical Be stars in 39 open clusters using medium resolution spectra in the wavelength range 3800-9000{AA}. One-third of the sample (48 stars in 18 clusters) has been studied for the first time. All these candidates were identified from an extensive survey of emission stars in young open clusters using slitless spectroscopy (Mathew et al., 2008MNRAS.388.1879M). This large data set covers CBe stars of various spectral types and ages found in different cluster environments in largely northern open clusters, and is used to study the spectral characteristics of CBe stars in cluster environments.
14183. Spectroscopy of Coma early-type galaxies
ID:
ivo://CDS.VizieR/J/ApJS/175/462
Title:
Spectroscopy of Coma early-type galaxies
Short Name:
J/ApJS/175/462
Date:
21 Oct 2021
Publisher:
CDS
Description:
The long-slit spectra obtained along the minor axis, offset major axis, and diagonal axis are presented for 12 E and S0 galaxies of the Coma Cluster drawn from a magnitude-limited sample studied before. The rotation curves, velocity dispersion profiles, and the H_3_ and H_4_ coefficients of the Hermite decomposition of the line-of-sight velocity distribution are derived. The radial profiles of the H{beta}, Mg, and Fe line strength indices are measured too. In addition, the surface photometry of the central regions of a subsample of four galaxies recently obtained with the Hubble Space Telescope is presented. The data will be used to construct dynamical models of the galaxies and study their stellar populations.
14184. Spectroscopy of Coma early-type galaxies. II.
ID:
ivo://CDS.VizieR/J/A+A/395/753
Title:
Spectroscopy of Coma early-type galaxies. II.
Short Name:
J/A+A/395/753
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present minor axis, offset major axis and one diagonal long slit spectra for 10 E and S0 galaxies of the Coma cluster drawn from a magnitude-limited sample studied before. We derive rotation curves, velocity dispersion profiles and the H_3_ and H_4_ coefficients of the Hermite decomposition of the line of sight velocity distribution. Moreover, we derive the line index profiles of Mg, Fe and Hbeta line indices and assess their errors. The data will be used to construct dynamical models of the galaxies and study their stellar populations.
14185. Spectroscopy of Damped Ly{alpha} (DLA) systems
ID:
ivo://CDS.VizieR/J/ApJ/769/54
Title:
Spectroscopy of Damped Ly{alpha} (DLA) systems
Short Name:
J/ApJ/769/54
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using a sample of 100 H I-selected damped Ly{alpha} (DLA) systems, observed with the High Resolution Echelle Spectrometer on the Keck I telescope, we present evidence that the scatter in the well-studied correlation between the redshift and metallicity of a DLA is largely due to the existence of a mass-metallicity relationship at each redshift. To describe the fundamental relations that exist between redshift, metallicity, and mass, we use a fundamental plane description, which is described by the following equation: [M/H]=(-1.9+/-0.5)+(0.74+/-0.21)*log{Delta}v_90_-(0.32+/-0.06)*z. Here, we assert that the velocity width, {Delta}v_90_, which is defined as the velocity interval containing 90% of the integrated optical depth, traces the mass of the underlying dark matter halo. This description provides two significant improvements over the individual descriptions of the mass-metallicity correlation and metallicity-redshift correlation. Firstly, the fundamental equation reduces the scatter around both relationships by about 20%, providing a more stringent constraint on numerical simulations modeling DLAs. Secondly, it confirms that the dark matter halos that host DLAs satisfy a mass-metallicity relationship at each redshift between redshifts 2 through 5.
14186. Spectroscopy of DA WD from the SDSS-DR4
ID:
ivo://CDS.VizieR/J/ApJ/730/128
Title:
Spectroscopy of DA WD from the SDSS-DR4
Short Name:
J/ApJ/730/128
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an improved spectroscopic and photometric analysis of hydrogen-line DA white dwarfs from the Sloan Digital Sky Survey Data Release 4 (SDSS DR4) based on model atmospheres that include improved Stark broadening profiles with non-ideal gas effects. We also perform a careful visual inspection of all spectroscopic fits with high signal-to-noise ratios (S/Ns>12) and present improved atmospheric parameters (T_eff_ and logg) for each white dwarf. Through a comparison of spectroscopic and photometric temperatures, we report the discovery of 35 DA+DB/DC double degenerate candidates and two helium-rich DA stars. We also determine that a cutoff at S/N=15 optimizes the size and quality of the sample for computing the mean mass of DA white dwarfs, for which we report a value of 0.613M_{sun}_. We compare our results to previous analyses of the SDSS DR4 and find a good agreement if we account for the shift produced by the improved Stark profiles. Finally, the properties of DA white dwarfs in the SDSS are weighed against those of the Villanova White Dwarf Catalog sample of Gianninas et al. (2009JPhCS.172a2021G).
14187. Spectroscopy of dwarf stars
ID:
ivo://CDS.VizieR/J/A+A/628/A49
Title:
Spectroscopy of dwarf stars
Short Name:
J/A+A/628/A49
Date:
21 Oct 2021
Publisher:
CDS
Description:
New space missions, such as NASA TESS or ESA PLATO, will focus on bright stars, which have been largely ignored by modern large surveys, especially in the northern sky. Spectroscopic information is of paramount importance in characterising the stars and analysing planets possibly orbiting them, and in studying the Galactic disc evolution. The aim of this work was to analyse all bright (V<8mag) F, G, and K dwarf stars using high-resolution spectra in the selected sky fields near the northern celestial pole. The observations were carried out with the 1.65m diameter telescope at the Molttai Astronomical Observatory and a fibre-fed high-resolution spectrograph covering a full visible wavelength range (4000-8500{AA}). The atmospheric parameters were derived using the classical equivalent width approach while the individual chemical element abundances were determined from spectral synthesis. For both tasks the one-dimensional plane-parallel LTE MARCS stellar model atmospheres were applied. Results. We determined the main atmospheric parameters, kinematic properties, orbital parameters, and stellar ages for 109 newly observed stars and chemical abundances of 23 chemical species for 249 F, G, and K dwarf stars observed in the present study and in our previous study. The [MgI/FeI] ratio was adopted to define the thin-disc ({alpha}-poor) and thick-disc ({alpha}-rich) stars in our sample. We explored the behaviour of 21 chemical species in the [El/FeI] versus [FeI/H] and [El/FeI] versus age planes, and compared the results with the latest Galactic chemical evolution models. We also explored [El/FeI] gradients according to the mean Galactocentric distances and maximum height above the Galactic plane.
14188. Spectroscopy of E and S0 galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/276/1341
Title:
Spectroscopy of E and S0 galaxies
Short Name:
J/MNRAS/276/1341
Date:
21 Oct 2021
Publisher:
CDS
Description:
Central velocity dispersions, Mg_2_ line indices, and radial velocities for 220 E and S0 galaxies are derived on basis of intermediate resolution spectroscopy. Galaxies in the following clusters have been observed: Abell 194, Abell 539, Abell 3381, Abell 3574, S639, S753, Doradus, HydraI (Abell 1060), and Grm15. The spectra cover 50 or 100nm centered on the magnesium triplet at 517.7nm. In this catalog we give the mean values of the parameters. The central velocity dispersion and the Mg_2_ line indices have been aperture corrected to a circular aperture with a diameter of 1.19h^-1^kpc, equivalent to 3.4arcsec at the distance of the Coma cluster. Values are also given for a circular aperture with radius equal to the effective radius of the galaxy (cf. Jorgensen et al. 1995, Cat. J/MNRAS/273/1097). The Mg_2_ indices are consistent with the Lick system. The typical uncertainty of the central velocity dispersion is 0.036 in log({sigma}), the typical uncertainty of Mg_2_ is 0.013. Further, literature data (velocity dispersions and Mg_2_ indices) for the clusters A194, DC2345-28 and Coma (A1656) have been brought on a homogeneous system and aperture corrected to the aperture sizes given above. The literature data are from Davies et al. (1987ApJS...64..581D), Dressler (1987ApJ...317....1D), Dressler & Shectman 1988 (J/AJ/95/284), Lucey & Carter (1988MNRAS.235.1177L), Lucey et al. (1991MNRAS.253..584L), and Guzman et al. (1992MNRAS.257..187G).
14189. Spectroscopy of 6 early-type galaxies
ID:
ivo://CDS.VizieR/J/AJ/146/45
Title:
Spectroscopy of 6 early-type galaxies
Short Name:
J/AJ/146/45
Date:
21 Oct 2021
Publisher:
CDS
Description:
Adaptive optics assisted SINFONI observations of the central regions of 10 early-type galaxies are presented. Based primarily on the SINFONI kinematics, 10 black hole (BH) masses occupying the high-mass regime of the M_BH_-{sigma} relation are derived using three-integral Schwarzschild models. The effect of dark matter (DM) inclusion on the BH mass is explored. The omission of a DM halo in the model results in a higher stellar mass-to-light ratio, especially when extensive kinematic data are used in the model. However, when the diameter of the sphere of influence--computed using the BH mass derived without a dark halo--is at least 10 times the point-spread function FWHM during the observations, it is safe to exclude a DM component in the dynamical modeling, i.e., the change in BH mass is negligible. When the spatial resolution is marginal, restricting the mass-to-light ratio to the right value returns the correct M_BH_ although a dark halo is not present in the model. Compared to the M_BH_-{sigma} and M_BH_-L relations of McConnell et al., the 10 BHs are all more massive than expected from the luminosities and 7 BH masses are higher than expected from the stellar velocity dispersions of the host bulges. Using new fitted relations, which include the 10 galaxies, we find that the space density of the most massive BHs (M_BH_>~10^9^M_{sun}_) estimated from the M_BH_-L relation is higher than the estimate based on the M_BH_-{sigma} relation and the latter is higher than model predictions based on quasar counts, each by about an order of magnitude.
14190. Spectroscopy of early-type galaxies
ID:
ivo://CDS.VizieR/J/AJ/116/2738
Title:
Spectroscopy of early-type galaxies
Short Name:
J/AJ/116/2738
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present central velocity dispersion measurements for 325 early-type galaxies in eight clusters and groups of galaxies, including new observations for 212 galaxies. The clusters and groups are the A262, A1367, Coma (A1656), A2634, Cancer, and Pegasus Clusters and the NGC 383 and NGC 507 Groups. The new measurements were derived from medium-dispersion spectra that cover 600{AA} centered on the Mg I b triplet at {lambda}~5175{AA}. Velocity dispersions were measured using the Tonry & Davis (1979AJ.....84.1511T) cross-correlation method, with a typical accuracy of 6%. A detailed comparison with other data sources is made.

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