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2541. Spectroscopy of the Galactic bar. I.
ID:
ivo://CDS.VizieR/J/ApJ/691/1387
Title:
Spectroscopy of the Galactic bar. I.
Short Name:
J/ApJ/691/1387
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use Fabry-Perot absorption line imaging spectroscopy to measure radial velocities using the CaII line in 3360 stars toward three lines of sight in the Milky Way's bar: Baade's Window and offset position at (l,b)~(+/-5.0,-3.5{deg}). This sample includes 2488 bar red clump giants, 339 bar M/K-giants, and 318 disk main-sequence stars. We measure the first four moments of the stellar velocity distribution of the red clump giants, and find it to be symmetric and flat-topped. We also measure the line-of-sight average velocity and dispersion of the red clump giants as a function of distance in the bar.
2542. Spectroscopy of UltraStrong Emission Line galaxies
ID:
ivo://CDS.VizieR/J/ApJ/668/853
Title:
Spectroscopy of UltraStrong Emission Line galaxies
Short Name:
J/ApJ/668/853
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe the results of a narrowband search for ultrastrong emission line galaxies (USELs) with EW(H{beta})>=30{AA}. A total of 542 candidate galaxies are found in a one-half square degree survey using two ~120{AA} filters centered at 8150 and 9140{AA} with Subaru SuprimeCam. Follow-up spectroscopy for randomly selected objects in the candidate sample with Keck II DEIMOS shows that they consist of [OIII] {lambda}5007-, [OII] {lambda}3727-, and H{alpha}-selected strong emission line galaxies at intermediate redshift (z<1) and Ly{alpha}-emitting galaxies at high redshift (z>>5).
2543. Spectroscopy of X-ray sources in ECDF-S
ID:
ivo://CDS.VizieR/J/ApJ/693/1713
Title:
Spectroscopy of X-ray sources in ECDF-S
Short Name:
J/ApJ/693/1713
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first results of our optical spectroscopy program aimed to provide redshifts and identifications for the X-ray sources in the Extended Chandra Deep Field South. A total of 339 sources were targeted using the IMACS spectrograph at the Magellan telescopes and the VIMOS spectrograph at the VLT. We measured redshifts for 186 X-ray sources, including archival data and a literature search. We find that the active galactic nucleus (AGN) host galaxies have on average redder rest-frame optical colors than nonactive galaxies, and that they live mostly in the "green valley". The dependence of the fraction of AGNs that are obscured on both luminosity and redshift is confirmed at high significance and the observed AGN spatial density is compared with the expectations from existing luminosity functions. These AGNs show a significant difference in the mid-IR to X-ray flux ratio for obscured and unobscured AGNs, which can be explained by the effects of dust self-absorption on the former. This difference is larger for lower luminosity sources, which is consistent with the dust opening angle depending on AGN luminosity.
2544. SPHERE and NaCo images of HD 19467B
ID:
ivo://CDS.VizieR/J/A+A/639/A47
Title:
SPHERE and NaCo images of HD 19467B
Short Name:
J/A+A/639/A47
Date:
23 Mar 2022 16:31:06
Publisher:
CDS
Description:
HD 19467 observations were performed with the VLT exoplanet imager SPHERE and the VLT adaptive optics camera NaCo to further characterize the spectral and orbital properties of the known T-type brown dwarf companion.
2545. SPIDERS BCGs gri photometry
ID:
ivo://CDS.VizieR/J/MNRAS/478/4952
Title:
SPIDERS BCGs gri photometry
Short Name:
J/MNRAS/478/4952
Date:
10 Dec 2021 13:51:48
Publisher:
CDS
Description:
We present a sample of 329 low-to intermediate-redshift (0.05<z<0.3) brightest cluster galaxies (BCGs) in X-ray-selected clusters from the SPectroscopic IDentification of eRosita Sources survey, a spectroscopic survey within Sloan Digital Sky Survey-IV (SDSS-IV). We define our BCGs by simultaneous consideration of legacy X-ray data from ROSAT, maximum-likelihood outputs from an optical cluster-finder algorithm and visual inspection. Using SDSS imaging data, we fit Sersic profiles to our BCGs in three bands (g, r, i) with SIGMA a GALFIT-based software wrapper. We examine the reliability of our fits by running our pipeline on ~10^4^ point spread function-convolved model profiles injected into eight random cluster fields; we then use the results of this analysis to create a robust subsample of 198 BCGs. We outline three cluster properties of interest: overall cluster X-ray luminosity (L_X_), cluster richness as estimated by REDMAPPER ({lambda}),and cluster halo mass (M_200_), which is estimated via velocity dispersion. In general, there are significant correlations with BCG stellar mass between all three environmental properties, but no significant trends arise with either Sersic index or effective radius. There is no major environmental dependence on the strength of the relation between effective radius and BCG stellar mass. Stellar mass therefore arises as the most important factor governing BCG morphology. Our results indicate that our sample consists of a large number of relaxed, mature clusters containing broadly homogeneous BCGs up to z~0.3, suggesting that there is little evidence for much ongoing structural evolution for BCGs in these systems.
2546. Spin Parity of Spiral Galaxies. III.
ID:
ivo://CDS.VizieR/J/ApJ/907/123
Title:
Spin Parity of Spiral Galaxies. III.
Short Name:
J/ApJ/907/123
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is a revised catalog of spiral winding direction of SDSS spiral galaxies published by Shamir (2017PASA...34...11S). Whether the spiral pattern as projected on the sky is S-wise or Z-wise (Shamir called them counter clock wise and clockwise, respectively) can be an unambiguous tool to identify whether the galaxy spin vector is pointing toward or away from us as all the spirals are safely regarded as trailing spirals (Iye et al., 2019ApJ...886..113S). We used Shamir's catalog to analyze the dipole anisotropy in their large-scale structure and found that there exist rather massive duplicated entries and a few other minor errors in the original catalog. In this revised version those duplicated entries are cleaned keeping the judgment of the spiral winding direction due to Shamir (2017PASA...34...11S) except for a several obviously inconsistent cases. These corrections were necessary to make analysis of the large scale distribution of spin vectors of galaxies of the SDSS sample in our paper.
2547. Spiral and lenticular galaxy brightness profiles
ID:
ivo://CDS.VizieR/J/AJ/116/1626
Title:
Spiral and lenticular galaxy brightness profiles
Short Name:
J/AJ/116/1626
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present one of the largest homogeneous sets of spiral and lenticular galaxy brightness profile decompositions completed to date. The 659 galaxies in our sample have been fitted with a de Vaucouleurs law for the bulge component and an inner-truncated exponential for the disk component. Of the 659 galaxies in the sample, 620 were successfully fitted with the chosen fitting functions. The fits are generally well defined, with more than 90% having rms deviations from the observed profile of less than 0.35mag. We find no correlations of fitting quality, as measured by these rms residuals, with either morphological type or inclination. Similarly, the estimated errors of the fitted coefficients show no significant trends with type or inclination. These decompositions form a useful basis for the study of the light distributions of spiral and lenticular galaxies. The object base is sufficiently large that well-defined samples of galaxies can be selected from it.
2548. Spiral arms Gaia EDR3
ID:
ivo://CDS.VizieR/J/A+A/651/A104
Title:
Spiral arms Gaia EDR3
Short Name:
J/A+A/651/A104
Date:
22 Feb 2022
Publisher:
CDS
Description:
Using the astrometry and integrated photometry from the Gaia Early Data Release 3 (EDR3), we map the density variations in the distribution of young Upper Main Sequence (UMS) stars, open clusters and classical Cepheids in the Galactic disk within several kiloparsecs of the Sun. Maps of relative over/under-dense regions for UMS stars in the Galactic disk are derived, using both bivariate kernel density estimators and wavelet transformations. The resulting overdensity maps exhibit large-scale arches, that extend in a clumpy but coherent way over the entire sampled volume, indicating the location of the spiral arms segments in the vicinity of the Sun. Peaks in the UMS overdensity are well-matched by the distribution of young and intrinsically bright open clusters. By applying a wavelet transformation to a sample of classical Cepheids, we find that their overdensities possibly extend the spiral arm segments on a larger scale (~10kpc from the Sun). While the resulting map based on the UMS sample is generally consistent with previous models of the Sagittarius-Carina spiral arm, the geometry of the arms in the III quadrant (galactic longitudes 180{deg}<l<270{deg}) differs significantly from many previous models. In particular we find that our maps favour a larger pitch angle for the Perseus arm, and that the Local Arm extends into the III quadrant at least 4kpc past the Sun's position, giving it a total length of at least 8kpc.
2549. Spiral structure of the Milky Way
ID:
ivo://CDS.VizieR/J/other/RAA/18.146
Title:
Spiral structure of the Milky Way
Short Name:
J/other/RAA/18.1
Date:
21 Oct 2021
Publisher:
CDS
Description:
The morphology and kinematics of the spiral structure of the Milky Way are long-standing problems in astrophysics. In this review we firstly summarize various methods with different tracers used to solve this puzzle. The astrometry of Galactic sources is gradually alleviating this difficult situation caused mainly by large distance uncertainties, as we can currently obtain accurate parallaxes (a few {mu}as) and proper motions (~1km/s) by using Very Long Baseline Interferometry (VLBI). On the other hand, the Gaia mission is providing the largest, uniform sample of parallaxes for O-type stars in the entire Milky Way. Based upon the VLBI maser and Gaia O-star parallax measurements, nearby spiral structures of the Perseus, Local, Sagittarius and Scutum Arms are determined in unprecedented detail. Meanwhile, we estimate fundamental Galactic parameters of the distance to the Galactic center, R_0_, to be 8.35+/-0.18kpc, and circular rotation speed at the Sun, {THETA}_0_, to be 240+/-10km/s. We found kinematic differences between O stars and interstellar masers: the O stars, on average, rotate faster, >8km/s than maser-traced high-mass star forming regions.
2550. Spitzer h and {chi} Persei candidate members
ID:
ivo://CDS.VizieR/J/ApJ/796/127
Title:
Spitzer h and {chi} Persei candidate members
Short Name:
J/ApJ/796/127
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyze very deep Infrared Array Camera and Multiband Imaging Photometer for Spitzer (MIPS) photometry of ~12500 members of the 14 Myr old Double Cluster, h and {chi} Persei, building upon our earlier, shallower Spitzer Cycle 1 studies. Numerous likely members show infrared (IR) excesses at 8 {mu}m and 24 {mu}m, indicative of circumstellar dust. The frequency of stars with 8 {mu}m excess is at least 2% for our entire sample, slightly lower (higher) for B/A stars (later type, lower mass stars). Optical spectroscopy also identifies gas in about 2% of systems, but with no clear trend between the presence of dust and gas. Spectral energy distribution modeling of 18 sources with detections at optical wavelengths through MIPS 24 {mu}m reveals a diverse set of disk evolutionary states, including a high fraction of transitional disks, though similar data for all disk-bearing members would provide constraints. Using Monte Carlo simulations, we combine our results with those for other young clusters to study the global evolution of dust/gas disks. For nominal cluster ages, the e-folding times ({tau}_0_) for the frequency of warm dust and gas are 2.75 Myr and 1.75 Myr, respectively. Assuming a revised set of ages for some clusters, these timescales increase to 5.75 and 3.75 Myr, respectively, implying a significantly longer typical protoplanetary disk lifetime than previously thought. In both cases, the transitional disk duration, averaged over multiple evolutionary pathways, is ~1 Myr. Finally, 24 {mu}m excess frequencies for 4-6 M_{sun}_ stars appear lower than for 1-2.5 M_{sun}_ stars in other 10-30 Myr old clusters.