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531. COSMOS AGN spectroscopic survey. I.
ID:
ivo://CDS.VizieR/J/ApJ/696/1195
Title:
COSMOS AGN spectroscopic survey. I.
Short Name:
J/ApJ/696/1195
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present optical spectroscopy for an X-ray and optical flux-limited sample of 677 XMM-Newton selected targets covering the 2deg^2^ Cosmic Evolution Survey field, with a yield of 485 high-confidence redshifts. The majority of the spectra were obtained over three seasons (2005-2007) with the Inamori Magellan Areal Camera and Spectrograph instrument on the Magellan (Baade) telescope. We also include in the sample previously published Sloan Digital Sky Survey spectra and supplemental observations with MMT/Hectospec. We detail the observations and classification analyses. The survey is 90% complete to flux limits of f_0.5-10keV_>8x10^-16-^erg/cm^2^/s and i^+^_AB_<22, where over 90% of targets have high-confidence redshifts. Making simple corrections for incompleteness due to redshift and spectral type allows for a description of the complete population to i^+^_AB_<23. The corrected sample includes a 57% broad emission line (Type 1, unobscured) active galactic nucleus (AGN) at 0.13<z<4.26, 25% narrow emission line (Type 2, obscured) AGN at 0.07<z<1.29, and 18% absorption line (host-dominated, obscured) AGN at 0<z<1.22 (excluding the stars that made up 4% of the X-ray targets). We show that the survey's limits in X-ray and optical fluxes include nearly all X-ray AGNs (defined by L_0.5-10keV_>3x10^42^erg/s) to z<1, of both optically obscured and unobscured types.
532. CO spectra of 55 LIRGs and ULIRGs
ID:
ivo://CDS.VizieR/J/A+A/628/A71
Title:
CO spectra of 55 LIRGs and ULIRGs
Short Name:
J/A+A/628/A71
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present IRAM-30m Telescope ^12^CO and ^13^CO observations of a sample of 55 luminous and ultraluminous infrared galaxies (LIRGs and ULIRGs) in the local universe. This sample is a subset of the Great Observatory All-Sky LIRG Survey (GOALS), for which we use ancillary multi-wavelength data to better understand their interstellar medium and star formation properties. Fifty-three (96%) of the galaxies are detected in ^12^CO, and 29 (52%) are also detected in ^13^CO above a 3{sigma} level. The median full width at zero intensity (FWZI) velocity of the CO line emission is 661km/s, and 54% of the galaxies show a multi-peak CO profile. Herschel photometric data is used to construct the far-IR spectral energy distribution of each galaxy, which are fit with a modified blackbody model that allows us to derive dust temperatures and masses, and infrared luminosities. We make the assumption that the gas-to-dust mass ratio of (U)LIRGs is comparable to local spiral galaxies with a similar stellar mass (i.e., gas/dust of mergers is comparable to their progenitors) to derive a CO-to-H_2_ conversion factor of <{alpha}>=1.8^+1.3^_0.8_M_{sun}_/(K.km/s/pc^2^); such a value is comparable to that derived for (U)LIRGs based on dynamical mass arguments. We derive gas depletion times of 400-600Myr for the (U)LIRGs, compared to the 1.3Gyr for local spiral galaxies. Finally, we re-examine the relationship between the ^12^CO/^13^CO ratio and dust temperature, confirming a transition to elevated ratios in warmer systems.
533. CO spectra of Virgo cluster galaxies
ID:
ivo://CDS.VizieR/J/A+A/590/A27
Title:
CO spectra of Virgo cluster galaxies
Short Name:
J/A+A/590/A27
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present ^12^CO(1-0) and ^12^CO(2-1) observations of a sample of 20 star-forming dwarfs selected from the Herschel Virgo Cluster Survey, with oxygen abundances ranging from 12+log(O/H)~8.1 to 8.8. CO emission is observed in ten galaxies and marginally detected in another one. CO fluxes correlate with the FIR 250um emission, and the dwarfs follow the same linear relation that holds for more massive spiral galaxies extended to a wider dynamical range. We compare different methods to estimate H_2_ molecular masses, namely a metallicity-dependent CO-to-H_2_ conversion factor and one dependent on H-band luminosity. The molecular-to-stellar mass ratio remains nearly constant at stellar masses <=10^9^M_{sun}_, contrary to the atomic hydrogen fraction, M_HI_/M*, which increases inversely with M*. The flattening of the M_H2_/M* ratio at low stellar masses does not seem to be related to the effects of the cluster environment because it occurs for both HI-deficient and HI-normal dwarfs. The molecular-to-atomic ratio is more tightly correlated with stellar surface density than metallicity, confirming that the interstellar gas pressure plays a key role in determining the balance between the two gaseous components of the interstellar medium. Virgo dwarfs follow the same linear trend between molecular gas mass and star formation rate as more massive spirals, but gas depletion timescales, tau_dep, are not constant and range between 100Myr and 6Gyr. The interaction with the Virgo cluster environment is removing the atomic gas and dust components of the dwarfs, but the molecular gas appears to be less affected at the current stage of evolution within the cluster. However, the correlation between HI deficiency and the molecular gas depletion time suggests that the lack of gas replenishment from the outer regions of the disc is lowering the star formation activity.
534. CO Tully-Fisher relation for host galaxies of QSOs
ID:
ivo://CDS.VizieR/J/ApJ/669/821
Title:
CO Tully-Fisher relation for host galaxies of QSOs
Short Name:
J/ApJ/669/821
Date:
21 Oct 2021
Publisher:
CDS
Description:
The integrated line width derived from CO spectroscopy provides a powerful tool to study the internal kinematics of extragalactic objects, including quasars at high redshift, provided that the observed line width can be properly translated to more conventionally used kinematical parameters of galaxies. We show, through the construction of a Ks-band CO Tully-Fisher relation for nearby galaxies spanning a wide range in infrared luminosity, that the CO line width measured at 20% of the peak intensity, when corrected for inclination and other effects, successfully recovers the maximum rotation velocity of the disk. The line width at 50% of the peak intensity performs much more poorly, in large part because CO lines have a wide range of profiles, which are shown to vary systematically with infrared luminosity. We present a practical prescription for converting observed CO line widths into the stellar velocity dispersion of the bulge ({sigma}*) and then apply it to a sample of low-redshift (z<~0.2) and high-redshift (1.4<~z<~6.4) quasars to study their host galaxies.
535. Coupling factors of 5166 KIC
ID:
ivo://CDS.VizieR/J/A+A/600/A1
Title:
Coupling factors of 5166 KIC
Short Name:
J/A+A/600/A1
Date:
21 Oct 2021
Publisher:
CDS
Description:
The power of asteroseismology relies on the capability of global oscillations to infer the stellar structure. For evolved stars, we benefit from unique information directly carried out by mixed modes that probe their radiative cores. This third article of the series devoted to mixed modes in red giants focuses on their coupling factors, which have remained largely unexploited up to now. With the measurement of coupling factors, we intend to give physical constraints on the regions surrounding the radiative core and the hydrogen-burning shell of subgiants and red giants. A new method for measuring the coupling factor of mixed modes was implemented, which was derived from the method recently implemented for measuring period spacings. This new method was automated so that it could be applied to a large sample of stars. Coupling factors of mixed modes were measured for thousands of red giants. They show specific variation with mass and evolutionary stage. Weak coupling is observed for the most evolved stars on the red giant branch only; large coupling factors are measured at the transition between subgiants and red giants as well as in the red clump. The measurement of coupling factors in dipole mixed modes provides a new insight into the inner interior structure of evolved stars. While the large frequency separation and the asymptotic period spacings probe the envelope and core, respectively, the coupling factor is directly sensitive to the intermediate region in between and helps determine its extent. Observationally, the determination of the coupling factor is a prior to precise fits of the mixed-mode pattern and can now be used to address further properties of the mixed-mode pattern, such as the signature of buoyancy glitches and core rotation.
536. CP stars magnetic fields catalog (2009)
ID:
ivo://CDS.VizieR/J/other/AstBu/71.302
Title:
CP stars magnetic fields catalog (2009)
Short Name:
J/other/AstBu/71
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of measuring longitudinal magnetic fields (B_e), rotation velocities (v_e_sini), and radial velocities (V_r_) of 44 stars observed with the Main Stellar Spectrograph (MSS) of the 6-m BTA telescope of the Special Astrophysical Observatory in 2009. Observations of standard stars without magnetic fields confirm the absence of systematic errors capable of introducing distortions into the longitudinal-field measurement results. In this work we comment on the results for each of the stars.
537. CP stars magnetic fields catalog (2007)
ID:
ivo://CDS.VizieR/J/other/AstBu/69.427
Title:
CP stars magnetic fields catalog (2007)
Short Name:
J/other/AstBu/69
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog presents the results of magnetic field measurements for 39 chemically peculiar and 3 normal main sequence stars used as standard stars. Observations were carried out with the Main Stellar Spectrograph of the Russian 6-m telescope during 2007. The accuracy analysis for the longitudinal magnetic field measurements of the stars confirms that the systematic errors do not exceed 10-20G and are within the quoted limits. The absence of significant instrumental deviations follows from the measurements of theBD CP stars with well-known B_e_ variation curves.
538. CP stars magnetic fields catalog (2010)
ID:
ivo://CDS.VizieR/J/other/AstBu/72.391
Title:
CP stars magnetic fields catalog (2010)
Short Name:
J/other/AstBu/72
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of measuring longitudinal magnetic fields (B_e_), rotation velocities (v_esini_), and radial velocities (V_r_) of 92 stars observed with the Main Stellar Spectrograph (MSS) of the 6-m BTA telescope of the Special Astrophysical Observatory in 2010. Observations of standard stars without magnetic fields confirm the absence of systematic errors capable of introducing distortions into the longitudinal-field measurement results.
539. CP stars magnetic fields catalog (2008)
ID:
ivo://CDS.VizieR/J/other/AstBu/70.444
Title:
CP stars magnetic fields catalog (2008)
Short Name:
J/other/AstBu/70
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of the magnetic field measurements of 37 chemically peculiar and 4 normal main sequence stars using circularly polarized spectra obtained in 2008 with a Zeeman analyzer on the Main Stellar Spectrograph (MSS) of the Russian 6-m telescope (BTA). Four new magnetic stars have been discovered (HD25999, HD35100, HD96237, and HD279021), the presence of a field was suspected in two stars (HD2887 and BD-12 2366), 16 previously known CP stars were continued to be monitored to study their fields. The results of the longitudinal magnetic field B_e_ measurements show that in stars with narrow spectral lines, systematic errors in B_e_ determination do not exceed 10-20G, which is within the statistical error. Our study of stars with reliable phase curves of the longitudinal field B_e_ show that there are no instrumental effects which can distort the observations.
540. Cr, Co, and Ni abundances for metal-poor red giants
ID:
ivo://CDS.VizieR/J/ApJS/237/18
Title:
Cr, Co, and Ni abundances for metal-poor red giants
Short Name:
J/ApJS/237/18
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present measurements of the abundances of chromium, cobalt, and nickel in 4113 red giants, including 2277 stars in globular clusters (GCs), 1820 stars in the Milky Way's dwarf satellite galaxies, and 16 field stars. We measured the abundances from mostly archival Keck/DEIMOS medium-resolution spectroscopy with a resolving power of R~6500 and a wavelength range of approximately 6500-9000{AA}. The abundances were determined by fitting spectral regions that contain absorption lines of the elements under consideration. We used estimates of temperature, surface gravity, and metallicity that we previously determined from the same spectra. We estimated systematic error by examining the dispersion of abundances within mono- metallic GCs. The median uncertainties for [Cr/Fe], [Co/Fe], and [Ni/Fe] are 0.20, 0.20, and 0.13, respectively. Finally, we validated our estimations of uncertainty through duplicate measurements, and we evaluated the accuracy and precision of our measurements through comparison to high-resolution spectroscopic measurements of the same stars.

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