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331. Accretion rate of AGNs from COSMOS surveys
ID:
ivo://CDS.VizieR/J/ApJ/733/60
Title:
Accretion rate of AGNs from COSMOS surveys
Short Name:
J/ApJ/733/60
Date:
21 Oct 2021
Publisher:
CDS
Description:
We show how accretion rate governs the physical properties of a sample of unobscured broad-line, narrow-line, and lineless active galactic nuclei (AGNs). We avoid the systematic errors plaguing previous studies of AGN accretion rates by using accurate intrinsic accretion luminosities (Lint) from well-sampled multiwavelength spectral energy distributions from the Cosmic Evolution Survey, and accurate black hole masses derived from virial scaling relations (for broad-line AGNs) or host-AGN relations (for narrow-line and lineless AGNs).
332. Accretion-rotation connection in NGC 2264
ID:
ivo://CDS.VizieR/J/A+A/599/A23
Title:
Accretion-rotation connection in NGC 2264
Short Name:
J/A+A/599/A23
Date:
21 Oct 2021
Publisher:
CDS
Description:
The low spin rates measured for solar-type stars at an age of a few Myr (~10% of the break-up velocity) indicate that some mechanism of angular momentum regulation must be at play in the early pre-main sequence. This may be associated with magnetospheric accretion and star-disk interaction, as suggested by observations that disk-bearing objects (CTTS) are slower rotators than diskless sources (WTTS) in young star clusters. We characterize the rotation properties for members of the star-forming region NGC 2264 (~3Myr) as a function of mass, and investigate the accretion-rotation connection at an age where about 50% of the stars have already lost their disks. We examined a sample of 500 cluster members (40% with disks, 60% without disks), distributed in mass between ~0.15 and 2M_{sun}_, whose photometric variations were monitored in the optical for 38 consecutive days with the CoRoT space observatory. Light curves were analyzed for periodicity using three different techniques: the Lomb-Scargle periodogram, the autocorrelation function and the string-length method. Periods were searched in the range between 0.17-days (i.e., 4h, twice the data sampling adopted) and 19-days (half the total time span). Period detections were confirmed using a variety of statistical tools (false alarm probability, Q-statistics), as well as visual inspection of the direct and phase-folded light curves.
333. Accurate astrometry & RVs of 4 multiple systems
ID:
ivo://CDS.VizieR/J/ApJ/838/54
Title:
Accurate astrometry & RVs of 4 multiple systems
Short Name:
J/ApJ/838/54
Date:
21 Oct 2021
Publisher:
CDS
Description:
This work extends the still modest number of multiple stars with known relative orbit orientation. Accurate astrometry and radial velocities are used jointly to compute or update outer and inner orbits in three nearby triple systems, HIP 101955 (orbital periods 38.68 and 2.51yr), HIP 103987 (19.20 and 1.035yr), HIP 111805 (30.13 and 1.50yr), and in one quadruple system, HIP 2643 (periods 70.3, 4.85, and 0.276yr), all composed of solar-type stars. The masses are estimated from the absolute magnitudes and checked using the orbits. The ratios of outer to inner periods (from 14 to 20) and the eccentricities of the outer orbits are moderate. These systems are dynamically stable, but not very far from the stability limit. In three systems, all orbits are approximately coplanar and have small eccentricity, while in HIP101955 the inner orbit with e=0.6 is highly inclined.
334. Accurate coordinates of Planetary Nebulae
ID:
ivo://CDS.VizieR/J/AN/323/484
Title:
Accurate coordinates of Planetary Nebulae
Short Name:
J/AN/323/484
Date:
21 Oct 2021
Publisher:
CDS
Description:
Accurate optical coordinates of 734 PNe, measured on the charts of the Digitized Palomar Sky Survey (DSS-2), are presented. As a result of the discussion about the external accuracy the constants -0.8" in RA and +0.8" in DEC should be added to the coordinates measured by us. They were used but rounded off already in CGPN(2000).
335. Accurate masses and radii of normal stars
ID:
ivo://CDS.VizieR/J/other/A+ARV/18.67
Title:
Accurate masses and radii of normal stars
Short Name:
J/other/A+ARV/18
Date:
21 Oct 2021
Publisher:
CDS
Description:
This article presents and discusses a critical compilation of accurate, fundamental determinations of stellar masses and radii. We have identified 95 detached binary systems containing 190 stars (94 eclipsing systems, and alpha Centauri) that satisfy our criterion that the mass and radius of both stars be known within errors of +/-3% accuracy or better. All of them are non-interacting systems, and so the stars should have evolved as if they were single. This sample more than doubles that of the earlier similar review by Andersen (Astron. Astrophys. Rev. 3:91-126, 1991), extends the mass range at both ends and, for the first time, includes an extragalactic binary. In every case, we have examined the original data and recomputed the stellar parameters with a consistent set of assumptions and physical constants.
336. Accurate OH maser positions from SPLASH. III.
ID:
ivo://CDS.VizieR/J/ApJS/247/5
Title:
Accurate OH maser positions from SPLASH. III.
Short Name:
J/ApJS/247/5
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present high spatial resolution observations of ground-state OH masers achieved with the Australia Telescope Compact Array (ATCA). These observations targeted 253 pointing centers containing OH maser candidates at all four ground-state OH transitions identified in the Southern Parkes Large-Area Survey in Hydroxyl (SPLASH) across 96deg^2^ of the southern Galactic plane (332{deg}<l<334{deg} and -2{deg}<b<+2{deg}, 344{deg}<l<355{deg} and -2{deg}<b<+2{deg}, 358{deg}<l<4{deg} and +2{deg}<b<+6{deg}, 5{deg}<l<10{deg} and -2{deg}<b<+2{deg}). We detect maser emission toward 236 fields and suggest that 7 out of 17 nondetections are due to the slightly lower sensitivity of the ATCA observations, combined with some temporal variability. The superior resolution provided by the ATCA data has allowed us to identify 362 OH maser sites in the 236 target fields. Almost half (160 of 362) of these masers have been detected for the first time. Comparison between these 362 maser sites and information presented in the literature allowed us to categorize 238 sites as evolved star sites (66%), 63 as star formation (17%), 8 as supernova remnants, and 53 as unknown maser sites (15%). We present an analysis of the OH masers across the full SPLASH survey range (176deg^2^) and find that the detection rate of 1.7GHz radio continuum sources (18%) is lower than that previously found at 8.2 and 9.2GHz (38%). We also find that the velocity separations of evolved star sites with symmetric 1612MHz maser profiles are generally smaller than those with asymmetric profiles.
337. Accurate OH maser positions. II. The GC.
ID:
ivo://CDS.VizieR/J/ApJS/239/15
Title:
Accurate OH maser positions. II. The GC.
Short Name:
J/ApJS/239/15
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present high spatial resolution observations of ground-state OH masers achieved using the Australia Telescope Compact Array (ATCA). These observations were conducted toward 171 pointing centers where OH maser candidates were identified previously in the Southern Parkes Large-Area Survey in Hydroxyl (SPLASH) toward the Galactic center region between Galactic longitudes of 355* and 5* and Galactic latitudes of -2{deg} and +2{deg}. We detect maser emission toward 162 target fields and suggest that six out of nine nondetections are due to intrinsic variability. Due to the superior spatial resolution of the follow-up ATCA observations, we have identified 356 OH maser sites in the 162 target fields with maser detections. Almost half (161 of 356) of these maser sites have been detected for the first time in these observations. After comparing the positions of these 356 maser sites to the literature, we find that 269 (76%) sites are associated with evolved stars (two of which are PNe), 31 (9%) are associated with star formation, and four are associated with supernova remnants; we were unable to determine the origin of the remaining 52 (15%) sites. Unlike the pilot region, the infrared colors of evolved star sites with symmetric maser profiles in the 1612MHz transition do not show obvious differences compared with those of evolved star sites with asymmetric maser profiles.
338. Accurate positions for 17124 galaxies
ID:
ivo://CDS.VizieR/J/A+AS/144/475
Title:
Accurate positions for 17124 galaxies
Short Name:
J/A+AS/144/475
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper gives accurate coordinates and diameters for 3301 galaxies, companions of UGC galaxies. (about 2764 companions were not yet available in electronic form). In addition previously poor equatorial coordinates are re-measured for 13823 galaxies. These coordinates which have an accuracy of 5'' or better will be used for facilitating the cross-identification with forthcoming catalogues of millions of galaxies.
339. Accurate Positions for MCG Galaxies
ID:
ivo://CDS.VizieR/J/PASP/110/779
Title:
Accurate Positions for MCG Galaxies
Short Name:
J/PASP/110/779
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have measured accurate celestial coordinates for over 4000 extragalactic objects primarily drawn from a list of MCG galaxies with no recently published accurate positions. We used IPAC's Skyview program to display FITS images clipped from the Digitized Sky Survey, and to measure the coordinates. The standard deviations in the new positions depend slightly on the measurement command used, but are on the order of 1.0 arcsec to 1.2 arcsec (internal errors). The table of data includes all the duplicate measurements we made, as well as corrections and additions made after the PASP paper was submitted, so has 5120 entries.
340. Accurate positions of 2978 SBS objects
ID:
ivo://CDS.VizieR/J/A+AS/147/169
Title:
Accurate positions of 2978 SBS objects
Short Name:
J/A+AS/147/169
Date:
21 Oct 2021
Publisher:
CDS
Description:
Optical positions of 2978 objects listed in the Second Byurakan Survey (SBS) were obtained using the Digitized Sky Survey (DSS), and are given with an rms un certainty ~1 arcsec in each coordinate.

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