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16441. Updated radial velocities from Gaia DR2
ID:
ivo://CDS.VizieR/J/A+A/653/A160
Title:
Updated radial velocities from Gaia DR2
Short Name:
J/A+A/653/A160
Date:
08 Feb 2022 14:02:40
Publisher:
CDS
Description:
Gaia's Early Third Data Release (EDR3) does not contain new radial velocities because these will be published in Gaia's full third data release (DR3), expected in the first half of 2022. To maximise the usefulness of EDR3, Gaia's second data release (DR2) sources (with radial velocities) are matched to EDR3 sources to allow their DR2 radial velocities to also be included in EDR3. This presents two considerations: (i) a list of 70365 sources with potentially contaminated DR2 radial velocities has been published; and (ii) EDR3 is based on a new astrometric solution and a new source list, which means sources in DR2 may not be in EDR3. The two aims of this work are: (i) investigate the list in order to improve the DR2 radial velocities being included in EDR3 and to avoid false-positive hypervelocity candidates; and (ii) match the DR2 sources (with radial velocities) to EDR3 sources. Methods. Thetwo methods of this work are: (i) unpublished, preliminary DR3 radial velocities of sources on the list, and high-velocity stars not on the list, are compared with their DR2 radial velocities to identify and remove contaminated DR2 radial velocities from EDR3; and (ii) proper motions and epoch position propagation is used to attempt to match all sources with radial velocities in DR2 to EDR3 sources. The comparison of DR2 and DR3 radial velocities is used to resolve match ambiguities. EDR3 contains 7209831 sources with a DR2 radial velocity, which is 99.8% of sources with a radial velocity in DR2 (7224631). 14800 radial velocities from DR2 are not propagated to any EDR3 sources because (i) 3871 from the list are found to either not have a DR3 radial velocity or it differs significantly from its DR2 value, and five high-velocity stars not on the list are confirmed to have contaminated radial velocities, in one case because of contamination from the non-overlapping Radial Velocity Spectrometer windows of a nearby, bright star; and (ii) 10924 DR2 sources could not be satisfactorily matched to any EDR3 sources, so their DR2 radial velocities are also missing from EDR3. The reliability of radial velocities in EDR3 has improved compared to DR2 because the update removes a small fraction of erroneous radial velocities (0.05% of DR2 radial velocities and 5.5% of the list). Lessons learnt from EDR3 (e.g. bright star contamination) will improve the radial velocities in future Gaia data releases. The main reason for radial velocities from DR2 not propagating to EDR3 is not related to DR2 radial velocity quality. It is because the DR2 astrometry is based on one component of close binary pairs, while EDR3 astrometry is based on the other component, which prevents these sources from being unambiguously matched.
16442. Updated 3rd Cat Variable Stars in Globular Clusters
ID:
ivo://CDS.VizieR/V/97
Title:
Updated 3rd Cat Variable Stars in Globular Clusters
Short Name:
V/97
Date:
21 Oct 2021
Publisher:
CDS
Description:
This Catalogue is an update to Helen Sawyer Hogg's Third Catalogue on Variable Stars in Globular Clusters (1973, David Dunlap Observatory Publications, Volume 3, Number 6). This update is based mainly on reference cards prepared by Helen Sawyer Hogg from articles published in the literature in the period 1973 to 1988. There are also some references entered from more recent literature and we are attempting to bring the catalogue up to date. Not all known globular clusters have been included, as the literature search is not at this point complete.
16443. Updated Type II supernova Hubble diagram
ID:
ivo://CDS.VizieR/J/A+A/611/A25
Title:
Updated Type II supernova Hubble diagram
Short Name:
J/A+A/611/A25
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present photometry and spectroscopy of nine Type II-P/L supernovae (SNe) with redshifts in the 0.045~<z~<0.335 range, with a view to re-examining their utility as distance indicators. Specifically, we apply the expanding photosphere method (EPM) and the standardized candle method (SCM) to each target, and find that both methods yield distances that are in reasonable agreement with each other. The current record-holder for the highest-redshift spectroscopically confirmed SN II-P is PS1-13bni (z=0.335^+0.009^_-0.012_), and illustrates the promise of Type II SNe as cosmological tools. We updated existing EPM and SCM Hubble diagrams by adding our sample to those previously published. Within the context of Type II SN distance measuring techniques, we investigated two related questions. First, we explored the possibility of utilising spectral lines other than the traditionally used FeII {lambda}5169 to infer the photospheric velocity of SN ejecta. Using local well-observed objects, we derive an epoch-dependent relation between the strong Balmer lines H{alpha}, H{beta} and FeII {lambda}5169 velocities that is applicable 30 to 40 days post-explosion. Motivated in part by the continuum of key observables such as rise time and decline rates exhibited from II-P to II-L SNe, we assessed the possibility of using Hubble-flow Type II-L SNe as distance indicators. These yield similar distances as the Type II-P SNe. Although these initial results are encouraging, a significantly larger sample of SNe II-L would be required to draw definitive conclusions.
16444. Updated X-ray view of the Hyades cluster
ID:
ivo://CDS.VizieR/J/A+A/640/A66
Title:
Updated X-ray view of the Hyades cluster
Short Name:
J/A+A/640/A66
Date:
21 Oct 2021
Publisher:
CDS
Description:
We revisit the X-ray properties of the main sequence Hyades members and the relation between X-ray emission and stellar rotation. As an input catalog for Hyades members, we combined three recent membership lists derived from Gaia DR2 data that include the Hyades core and its tidal tails. We searched for X-ray detections of the main sequence Hyades members in the ROSAT all-sky survey (RASS), and pointings from ROSAT, the Chandra X-Ray Observatory, and XMM-Newton. Furtmermore, we adopted rotation periods derived from Kepler's K2 mission and other resources. We find an X-ray detection for 281 of 1066 bona fide main sequence Hyades members and provide statistical upper limits for the undetected sources. The majority of the X-ray detected stars are located in the Hyades core because of its generally smaller distance to the sun. F- and G-type stars have the highest detection fraction (72%), while K- and M-type dwarfs have lower detection rates (22 %). The X-ray luminosities of the detected members range from about 2x10^27^ for late M-type dwarfs to approximately 2x10^30^erg/s for active binaries. The X-ray luminosity distribution functions formally differ for the members in the core and tidal tails, which is likely caused by a larger fraction of field stars in our Hyades tails sample. Compared to previous studies, our sample is slightly fainter in X-rays due to differences in the Hyades membership list used; furthermore, we extend the X-ray luminosity distribution to fainter luminosities. The X-ray activity of F- and G-type stars is well defined at F_X_/F_bol_=10^-5^. The fractional X-ray luminosity and its spread increases to later spectral types reaching the saturation limit (F_X_/F_bol_=10^-3^) for members later than spectral type M3. Confirming previous results, the X-ray flux varies by less than a factor of three between epochs for the 104 Hyades members with multiple epoch data, significantly less than expected from solar-like actvity cycles. Rotation periods are found for 204 Hyades members, with about half of them being detected in X-rays. The activity-rotation relation derived for the coeval Hyades members has properties very similar to those obtained by other authors investigating stars of different ages.
16445. Updated Zwicky Catalog
ID:
ivo://nasa.heasarc/uzc
Title:
Updated Zwicky Catalog
Short Name:
UZC
Date:
08 Nov 2024
Publisher:
NASA/GSFC HEASARC
Description:
The Zwicky Catalog of Galaxies, with a magnitude limit m&lt;sub&gt;Zw&lt;/sub&gt; &lt;= 15.5, has been the basis for the Center for Astrophysics (CfA) redshift surveys. To date, analyses of the Zwicky Catalog and redshift surveys based on it have relied on heterogeneous sets of galaxy coordinates and redshifts. In this Updated Zwicky Catalog (UZC), some of the inadequacies of previous catalogs are corrected by providing (1) coordinates with ~&lt;2 arcsecond errors for all of the 19,369 catalog galaxies, (2) homogeneously estimated redshifts cz (radial velocities) for the majority (98%) of the data taken at the CfA (14,632 spectra), and (3) an estimate of the remaining &quot;blunder&quot; rate for both the CfA redshifts and for those compiled from the literature. For the reanalyzed CfA data a calibrated, uniformly determined error and an indication of the presence of emission lines in each spectrum are included. Redshifts (radial velocities) are provided for the 7257 galaxies in the CfA2 redshift survey that were not previously published; for another 5625 CfA redshifts (radial velocities), the remeasured or uniformly rereduced values are listed. Among the new measurements, 1807 are members of UZC &quot;multiplets&quot; associated with the original Zwicky catalog position in the coordinate range where the catalog is 98% complete. These multiplets provide new candidates for examination of tidal interaction among galaxies. All of the new redshifts (radial velocities) correspond to UZC galaxies with properties recorded in the CfA redshift compilation known as ZCAT. The redshift catalog included in the UZC is ~96% complete to m&lt;sub&gt;Zw&lt;/sub&gt; &lt;= 15.5 and ~98% complete (12,925 galaxies out of a total of 13,150) for the right ascension ranges 20 hr &gt;= RA(1950) &lt;= 4 hr and 8 hr &lt;= RA(1950) &lt;= 17 hr and the declination range -2.5 degrees &lt;= Dec(1950) &lt;= 50 degrees. This more complete region includes all of the CfA2 survey as analyzed to the date of the publication of the UZC (1999). This database was created by the HEASARC in October 2000 based on a machine-readable version obtained from the CDS (Catalog J/PASP/111/438). It was slightly revised in February 2001 (the &#39;redshift&#39; parameters were renamed as &#39;radial velocity&#39; parameters to conform with the usage in other similar HEASARC extragalactic catalogs). This is a service provided by NASA HEASARC .
16446. Updated Zwicky catalog (UZC)
ID:
ivo://CDS.VizieR/J/PASP/111/438
Title:
Updated Zwicky catalog (UZC)
Short Name:
J/PASP/111/438
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Zwicky Catalog of galaxies (ZC), with m_Zw_<=15.5, has been the basis for the Center for Astrophysics (CfA) redshift surveys. To date, analyses of the ZC and redshift surveys based on it have relied on heterogeneous sets of galaxy coordinates and redshifts. Here we correct some of the inadequacies of previous catalogs by providing (1) coordinates with ~<2" errors for all of the 19,369 catalog galaxies, (2) homogeneously estimated redshifts for the majority (98%) of the data taken at the CfA (14,632 spectra), and (3) an estimate of the remaining "blunder" rate for both the CfA redshifts and for those compiled from the literature. For the reanalyzed CfA data we include a calibrated, uniformly determined error and an indication of the presence of emission lines in each spectrum. We provide redshifts for 7257 galaxies in the CfA2 redshift survey not previously published; for another 5625 CfA redshifts we list the remeasured or uniformly rereduced value. Among our new measurements, 1807 are members of UZC "multiplets" associated with the original Zwicky catalog position in the coordinate range where the catalog is 98% complete.
16447. Update of INTEGRAL/IBIS AGN catalogue
ID:
ivo://CDS.VizieR/J/MNRAS/460/19
Title:
Update of INTEGRAL/IBIS AGN catalogue
Short Name:
J/MNRAS/460/19
Date:
21 Oct 2021
Publisher:
CDS
Description:
In the most recent IBIS survey based on observations performed during the first 1000 orbits of INTEGRAL, are listed 363 high-energy emitters firmly associated with AGN, 107 of which are reported here for the first time. We have used X-ray data to image the IBIS 90 per cent error circle of all the AGN in the sample of 107, in order to obtain the correct X-ray counterparts, locate them with arcsec accuracy and therefore pinpoint the correct optical counterparts. This procedure has led to the optical and spectral characterization of the entire sample. This new set consists of 34 broad line or type 1 AGN, 47 narrow line or type 2 AGN, 18 blazars and 8 sources of unknown class. These eight sources have been associated with AGN from their positional coincidence with 2MASX/Radio/X-ray sources. Seven high-energy emitters have been included since they are considered to be good AGN candidates. Spectral analysis has been already performed on 55 objects and the results from the most recent and/or best statistical measurements have been collected. For the remaining 52 sources, we report the spectral analysis for the first time in this work. We have been able to obtain the full X-ray coverage of the sample making use of data from Swift/XRT, XMM-Newtonand NuSTAR. In addition to the spectral characterization of the entire sample, this analysis has enabled us to identify peculiar sources and by comparing different data sets, highlight flux variability in the 2-10keV and 20-40keV bands.
16448. Upper Sco members rotational velocities
ID:
ivo://CDS.VizieR/J/ApJ/745/56
Title:
Upper Sco members rotational velocities
Short Name:
J/ApJ/745/56
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present projected rotational velocities for 20 early-type (B8-A9) and 74 late-type (F2-M8) members of the ~5 Myr old Upper Scorpius OB Association derived from high-dispersion optical spectra obtained with the High Resolution Echelle Spectrometer on Keck I and the Magellan Inamori Kyocera Echelle on the Magellan Clay telescope. The spectroscopic sample is composed of stars and brown dwarfs with infrared signatures of circumstellar disks, both primordial and debris, and non-excess sources of comparable spectral type. We merge projected rotational velocities, accretion diagnostics, and Spitzer Space Telescope Infrared Array Camera and Multiband Imaging Photometer for Spitzer 24 {mu}m photometry to examine the relationship between rotation and circumstellar disks. The rotational velocities are strongly correlated with spectral type, a proxy for mass, such that the median vsin i for B8-A9-type stars is: 195+/-70km/s, F2-K4: 37.8+/-7.4km/s, K5-K9: 13.8^+21.3^_-8.2_km/s, M0-M5: 16.52+/-5.3km/s, and M5.5-M8: 17.72+/-8.1km/s. We find with a probability of >=0.99 that M-type stars and brown dwarfs having infrared excess suggestive of circumstellar disks rotate more slowly than their non-excess counterparts. A similar correlation is present among F2-K9-type stars, but only at the ~97% confidence level. Among the early-type (B8-A9) members, rotational velocities of the debris-disk and non-disk populations are indistinguishable. Considering the late-type (F2-M8) stars and brown dwarfs, we find a low fraction of slowly rotating, non-excess sources relative to younger star-forming regions, suggesting that most have spun up following disk dissipation. The few late-type (F2-M5) debris disk sources, which may be representative of stars that have recently dispersed their inner disks, are evenly divided between slow and moderate rotators.
16449. Upper Sco OB association IRAC observations
ID:
ivo://CDS.VizieR/J/ApJ/651/L49
Title:
Upper Sco OB association IRAC observations
Short Name:
J/ApJ/651/L49
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present 4.5, 8 and 16um photometry from the Spitzer Space Telescope for 204 stars in the Upper Scorpius OB association. The data are used to investigate the frequency and properties of circumstellar disks around stars with masses between 0.1 and 20 at an age of 5Myr. We identify 35 stars that have emission at 8 or 16um in excess of the stellar photosphere.
16450. Upper Scorpius members
ID:
ivo://CDS.VizieR/J/other/NatAs/6.89
Title:
Upper Scorpius members
Short Name:
J/other/NatAs/6.
Date:
03 Mar 2022 16:55:14
Publisher:
CDS
Description:
The nature and origin of free-floating planets (FFPs) are still largely unconstrained because of a lack of large homogeneous samples to enable a statistical analysis of their properties. So far, most FFPs have been discovered using indirect methods; microlensing surveys have proved particularly successful to detect these objects down to a few Earth masses. However, the ephemeral nature of microlensing events prevents any follow-up observations and individual characterization. Several studies have identified FFPs in young stellar clusters and the Galactic field but their samples are small or heterogeneous in age and origin. Here we report the discovery of between 70 and 170 FFPs (depending on the assumed age) in the region encompassing Upper Scorpius and Ophiuchus, the closest young OB association to the Sun. We found an excess of FFPs by a factor of up to seven compared with core-collapse model predictions, demonstrating that other formation mechanisms may be at work. We estimate that ejection from planetary systems might have a contribution comparable to that of core collapse in the formation of FFPs. Therefore, ejections due to dynamical instabilities in giant exoplanet systems must be frequent within the first 10Myr of a system's life.

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