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2521. 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.
2522. Spectroscopic follow-up of the QUBRICS quasars
ID:
ivo://CDS.VizieR/J/ApJS/250/26
Title:
Spectroscopic follow-up of the QUBRICS quasars
Short Name:
J/ApJS/250/26
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of the spectroscopic follow-up of the QUasars as BRIght beacons for Cosmology in the Southern Hemisphere (QUBRICS; Calderone+ 2019, J/ApJ/887/268) survey. The selection method is based on a machine-learning approach applied to photometric catalogs, covering an area of ~12400deg^2^ in the Southern Hemisphere. The spectroscopic observations started in 2018 and identified 55 new, high-redshift (z>=2.5), bright (i<=18) quasi-stellar objects (QSOs), with the catalog published in late 2019. Here we report the current status of the survey, bringing the total number of bright QSOs at z>=2.5 identified by QUBRICS to 224. The success rate of the QUBRICS selection method, in its most recent training, is estimated to be 68%. The predominant contaminant turns out to be lower-z QSOs at z<2.5. This survey provides a unique sample of bright QSOs at high z available for a number of cosmological investigations. In particular, carrying out the redshift drift measurements (Sandage Test) in the Southern Hemisphere, using the High Resolution Spectrograph at the 39m Extremely Large Telescope appears to be possible with less than 2500hr of observations spread over 30 targets in 25yr.
2523. Spectroscopic HK' index for 3 globular clusters
ID:
ivo://CDS.VizieR/J/ApJS/216/19
Title:
Spectroscopic HK' index for 3 globular clusters
Short Name:
J/ApJS/216/19
Date:
21 Oct 2021
Publisher:
CDS
Description:
There is increasing evidence for the presence of multiple red giant branches (RGBs) in the color-magnitude diagrams of massive globular clusters (GCs). In order to investigate the origin of this split on the RGB, we have performed new narrow-band Ca photometry and low-resolution spectroscopy for M22, NGC 1851, and NGC 288. We find significant differences (more than 4{sigma}) in calcium abundance from the spectroscopic HK' index for M22 and NGC 1851. We also find more than 8{sigma} differences in CN-band strength between the Ca-strong and Ca-weak subpopulations for these GCs. For NGC 288, however, a large difference is detected only in the CN strength. The calcium abundances of RGB stars in this GC are identical to within the errors. This is consistent with the conclusion from our new Ca photometry where the RGB splits are confirmed in M22 and NGC 1851, but not in NGC 288. We also find interesting differences in the CN-CH correlations among these GCs. While CN and CH are anti-correlated in NGC 288, they show a positive correlation in M22. NGC 1851, however, shows no difference in CH between the two groups of stars with different CN strengths. We suggest that all of these systematic differences would be best explained by how strongly Type II supernovae enrichment has contributed to the chemical evolution of these GCs.
2524. Spectroscopic indexes of BCGs
ID:
ivo://CDS.VizieR/J/MNRAS/398/133
Title:
Spectroscopic indexes of BCGs
Short Name:
J/MNRAS/398/133
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper is part of a series devoted to the study of the stellar populations in brightest cluster galaxies (BCGs), aimed at setting constraints on the formation and evolution of these objects. We have obtained high signal-to-noise ratio, long-slit spectra of 49 BCGs in the nearby Universe. Here, we derive single stellar population (SSP)-equivalent ages, metallicities and alpha-abundance ratios in the centres of the galaxies using the Lick system of absorption line indices.
2525. Spectroscopic Indicators in SeisMic Archive (SISMA)
ID:
ivo://CDS.VizieR/J/AJ/152/207
Title:
Spectroscopic Indicators in SeisMic Archive (SISMA)
Short Name:
J/AJ/152/207
Date:
21 Oct 2021
Publisher:
CDS
Description:
We created a large database of physical parameters and variability indicators by fully reducing and analyzing the large number of spectra taken to complement the asteroseismic observations of the COnvection, ROtation and planetary Transits (CoRoT) satellite. 7103 spectra of 261 stars obtained with the ESO echelle spectrograph HARPS have been stored in the VO-compliant database Spectroscopic Indicators in a SeisMic Archive (SISMA), along with the CoRoT photometric data of the 72 CoRoT asteroseismic targets. The remaining stars belong to the same variable classes of the CoRoT targets and were observed to better characterize the properties of such classes. Several useful variability indicators (mean line profiles, indices of differential rotation, activity and emission lines) together with vsini and radial-velocity measurements have been extracted from the spectra. The atmospheric parameters T_eff_,logg, and [Fe/H] have been computed following a homogeneous procedure. As a result, we fully characterize a sample of new and known variable stars by computing several spectroscopic indicators, also providing some cases of simultaneous photometry and spectroscopy.
2526. Spectroscopic members of COSMOS X-ray systems
ID:
ivo://CDS.VizieR/J/ApJ/880/142
Title:
Spectroscopic members of COSMOS X-ray systems
Short Name:
J/ApJ/880/142
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate spectroscopic properties of galaxy systems identified based on deep X-ray observations in the Cosmic Evolution Survey (COSMOS) field. The COSMOS X-ray system catalog we use includes 180 X-ray systems to a limiting flux of 1.0x10^-15^erg/cm^2^/s, an order of magnitude deeper than the future e-ROSITA survey. We identify spectroscopic members of these X-ray systems based on the spectroscopic catalog constructed by compiling various spectroscopic surveys including 277 new measurements; 146 X-ray systems are spectroscopically identified groups with more than three spectroscopic members. We identify 2196 spectroscopic redshifts of member candidates in these X-ray systems. The X-ray luminosity (L_X_)-velocity dispersion ({sigma}_v_) scaling relation of the COSMOS X-ray systems is consistent with that of massive X-ray clusters. One of the distinctive features of the COSMOS survey is that it covers the X-ray luminosity range where poor groups overlap the range for extended emission associated with individual quiescent galaxies. We assess the challenges posed by the complex morphology of the distribution of systems with low X-ray luminosity, including groups and individual quiescent galaxies, in the L_x_-{sigma}_v_ plane.
2527. Spectroscopic members of Segue 2 galaxy
ID:
ivo://CDS.VizieR/J/ApJ/770/16
Title:
Spectroscopic members of Segue 2 galaxy
Short Name:
J/ApJ/770/16
Date:
21 Oct 2021
Publisher:
CDS
Description:
Segue 2, discovered by Belokurov et al. (2009, Cat. J/MNRAS/397/1748), is a galaxy with a luminosity of only 900L_{sun}_. We present Keck/DEIMOS spectroscopy of 25 members of Segue 2 - a threefold increase in spectroscopic sample size. The velocity dispersion is too small to be measured with our data. The upper limit with 90% (95%) confidence is {sigma}_v_<2.2(2.6)km/s, the most stringent limit for any galaxy. The corresponding limit on the mass within the three-dimensional half-light radius (46pc) is M_1/2_<1.5(2.1)x10^5^M_{sun}_. Segue 2 is the least massive galaxy known. We identify Segue 2 as a galaxy rather than a star cluster based on the wide dispersion in [Fe/H] (from -2.85 to -1.33) among the member stars. The stars' [{alpha}/Fe] ratios decline with increasing [Fe/H], indicating that Segue 2 retained Type Ia supernova ejecta despite its presently small mass and that star formation lasted for at least 100 Myr. The mean metallicity, <[Fe/H]>=-2.22+/-0.13 (about the same as the Ursa Minor galaxy, 330 times more luminous than Segue 2), is higher than expected from the luminosity-metallicity relation defined by more luminous dwarf galaxy satellites of the Milky Way. Segue 2 may be the barest remnant of a tidally stripped, Ursa Minor-sized galaxy. If so, it is the best example of an ultra-faint dwarf galaxy that came to be ultra-faint through tidal stripping. Alternatively, Segue 2 could have been born in a very low mass dark matter subhalo (v_max_<10km/s), below the atomic hydrogen cooling limit.
2528. Spectroscopic monitoring of blazar S5 0716+714
ID:
ivo://CDS.VizieR/J/ApJ/902/42
Title:
Spectroscopic monitoring of blazar S5 0716+714
Short Name:
J/ApJ/902/42
Date:
10 Mar 2022 15:02:00
Publisher:
CDS
Description:
In this paper, we report new results of spectroscopic observations of {gamma}-ray blazar S5 0716+714 from 2019 September to 2020 March with the 2.4m optical telescope at Lijiang Observatory of Yunnan Observatories. The median cadence of observations is ~1 day. During the second observation period (Epoch2), the observational data reveal an extremely bright state and a bluer-when-brighter (BWB) chromatism. The BWB trend of Epoch2 differs significantly from that of the first observation period (Epoch1). A significantly brightness-dependent BWB chromatism emerges in the total data of Epoch1 and Epoch2. The BWB trend becomes weaker toward the brighter states, and likely becomes saturated at the highest state. Based on a log-parabolic function, a power law of synchrotron peak flux and frequency {nu}p, and a power law of the curvature of synchrotron spectrum and its {nu}p, simulation well reproduces the brightness-dependent BWB trend of S5 0716+714. The BWB trend is seemingly controlled by the shift of {nu}p with respect to the observational window, and effectively may be dominated by the variations of electron average energy and magnetic field in the emitting region.
2529. Spectroscopic observations of globular clusters
ID:
ivo://CDS.VizieR/J/MNRAS/405/839
Title:
Spectroscopic observations of globular clusters
Short Name:
J/MNRAS/405/839
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of medium-resolution spectroscopy of 28 globular clusters (GCs) in six nearby galaxies of different luminosities and morphological types, situated in M33 (15 objects), M31 (three), IC10 (four), UGCA86 (four), Holmberg IX (one) and DDO71 (one) obtained at the Special Astrophysical Observatory 6-m telescope. Measurements of Lick absorption line indices and comparison with Simple Stellar Population models enabled us to obtain their spectroscopic ages, metallicities and {alpha}-element to Fe abundance ratios.
2530. Spectroscopic observations of V380 Ori
ID:
ivo://CDS.VizieR/J/AZh/71/572
Title:
Spectroscopic observations of V380 Ori
Short Name:
J/AZh/71/572
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results of spectral observations of the Ae/Be star V380 Ori in the optical and near-IR ranges for 1976 to 1991, are presented. The spectra were obtained on various telescopes and spectrographs including the Main Stellar Spectrograph of the BTA six-meter telescope. For 270 bright emission lines, the intensities, equivalent widths, half-widths, radial velocities, and variability amplitudes are given.

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