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1871. Survey of Surveys. I. Radial velocities
ID:
ivo://CDS.VizieR/J/A+A/659/A95
Title:
Survey of Surveys. I. Radial velocities
Short Name:
J/A+A/659/A95
Date:
11 Mar 2022 07:44:42
Publisher:
CDS
Description:
We present a comprehensive catalogue, the Survey of Surveys (SoS), built by homogeneously merging the radial velocity (RV) determinations of the largest ground-based spectroscopic surveys to date, such as APOGEE, GALAH, Gaia-ESO, RAVE, and LAMOST, using Gaia as reference. This pilot study serves to prove the concept and to test the methodology that we plan to apply in the future to the stellar parameters and abundance ratios as well. We have devised a multi-staged procedure that includes: i) the cross match between Gaia and the spectroscopic surveys using the official Gaia cross-match algorithm, ii) the normalization of uncertainties using repeated measurements or the three-cornered hat method, iii) the cross calibration of the RVs as a function of the main parameters they depend on (magnitude, effective temperature, surface gravity, metallicity, and signal-to-noise ratio) to remove trends and zero point offsets, and iv) the comparison with external high-resolution samples, such as the Gaia RV standards and the Geneva-Copenhagen survey, to validate the homogenization procedure and to calibrate the RV zero-point of the SoS catalogue. We provide the largest homogenized RV catalogue to date, containing almost 11 million stars, of which about half come exclusively from Gaia and half in combination with the ground-based surveys. We estimate the accuracy of the RV zero-point to be about 0.16-0.31km/s and the RV precision to be in the range 0.05-1.50km/s depending on the type of star and on its survey provenance. We validate the SoS RVs with open clusters from a high resolution homogeneous samples and provide the systemic velocity of 55 individual open clusters. Additionally, we provide median RVs for 532 clusters recently discovered by Gaia data.
1872. Surveys of asteroid rotation periods using iPTF
ID:
ivo://CDS.VizieR/J/ApJS/219/27
Title:
Surveys of asteroid rotation periods using iPTF
Short Name:
J/ApJS/219/27
Date:
21 Oct 2021
Publisher:
CDS
Description:
Two dedicated asteroid rotation-period surveys have been carried out in the R band with ~20 minute cadence using the intermediate Palomar Transient Factory (iPTF) during 2014 January 6-9 and February 20-23. The total survey area covered 174deg^2^ in the ecliptic plane. Reliable rotation periods for 1438 asteroids are obtained from a larger data set of 6551 mostly main-belt asteroids, each with >=10 detections. Analysis of 1751, PTF-based, reliable rotation periods clearly shows the spin barrier at ~2hr for rubble-pile asteroids. We found a new large super-fast rotator, 2005 UW163, and another five candidates as well. For asteroids of 3<D<15km, our spin-rate distribution shows a number decrease along with frequency after 5 rev/day, which is consistent with the results of the Asteroid Light Curve Database. The discrepancy between our work and that of Pravec et al. (update 2014 April 20) comes mainly from asteroids with {Delta}_m_<0.2mag, which could be the result of different survey strategies. For asteroids with D<3km, we see a significant number drop at f=6rev/day. The relatively short YORP effect timescale for small asteroids could have spun up those elongated objects to reach their spin-rate limit resulting in breakup to create such a number deficiency. We also see that the C-type asteroids show a smaller spin-rate limit than the S-type, which agrees with the general impression that C-type asteroids have a lower bulk density than S-type asteroids.
1873. SweetSpot DR1: 74 SNe Ia in 36 nights on WIYN+WHIRC
ID:
ivo://CDS.VizieR/J/AJ/155/201
Title:
SweetSpot DR1: 74 SNe Ia in 36 nights on WIYN+WHIRC
Short Name:
J/AJ/155/201
Date:
21 Oct 2021
Publisher:
CDS
Description:
SweetSpot is a 3 yr National Optical Astronomy Observatory (NOAO) survey program to observe Type Ia supernovae (SNe Ia) in the smooth Hubble flow with the WIYN High-resolution Infrared Camera (WHIRC) on the WIYN 3.5 m telescope. We present data from the first half of this survey, covering the 2011B-2013B NOAO semesters and consisting of 493 calibrated images of 74 SNe Ia observed in the rest-frame near-infrared (NIR) in the range 0.02<z<0.09. Because many observed supernovae require host-galaxy subtraction from templates taken in later semesters, this release contains only the 186 NIR (JHK_s_) data points for the 33 SNe Ia that do not require host-galaxy subtraction. The sample includes four objects with coverage beginning before the epoch of B-band maximum and 27 beginning within 20 days of B-band maximum. We also provide photometric calibration between the WIYN+WHIRC and Two Micron All-Sky Survey (2MASS) systems, along with light curves for 786 2MASS stars observed alongside the SNe Ia. This work is the first in a planned series of three SweetSpot Data Releases. Future releases will include the full set of images from all 3 yr of the survey, including host-galaxy reference images and updated data processing with host-galaxy reference subtraction. SweetSpot will provide a well-calibrated sample that will help improve our ability to standardize distance measurements to SNe Ia, examine the intrinsic optical-NIR colors of SNe Ia at different epochs, explore the nature of dust in other galaxies, and act as a stepping-stone for more distant, potentially space-based surveys.
1874. Swift AGN and Cluster Survey (SACS). I.
ID:
ivo://CDS.VizieR/J/ApJS/218/8
Title:
Swift AGN and Cluster Survey (SACS). I.
Short Name:
J/ApJS/218/8
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Swift active galactic nucleus (AGN) and Cluster Survey (SACS) uses 125deg^2^ of Swift X-ray Telescope serendipitous fields with variable depths surrounding {gamma}-ray bursts to provide a medium depth (4x10^-15^erg/cm2/s) and area survey filling the gap between deep, narrow Chandra/XMM-Newton surveys and wide, shallow ROSAT surveys. Here, we present a catalog of 22563 point sources and 442 extended sources and examine the number counts of the AGN and galaxy cluster populations. SACS provides excellent constraints on the AGN number counts at the bright end with negligible uncertainties due to cosmic variance, and these constraints are consistent with previous measurements. We use Wide-field Infrared Survey Explorer (WISE) mid-infrared (MIR) colors to classify the sources. For AGNs we can roughly separate the point sources into MIR-red and MIR-blue AGNs, finding roughly equal numbers of each type in the soft X-ray band (0.5-2keV), but fewer MIR-blue sources in the hard X-ray band (2-8keV). The cluster number counts, with 5% uncertainties from cosmic variance, are also consistent with previous surveys but span a much larger continuous flux range. Deep optical or IR follow-up observations of this cluster sample will significantly increase the number of higher-redshift (z>0.5) X-ray-selected clusters.
1875. Swift AGN and Cluster Survey (SWCL). II. SDSS
ID:
ivo://CDS.VizieR/J/ApJS/222/13
Title:
Swift AGN and Cluster Survey (SWCL). II. SDSS
Short Name:
J/ApJS/222/13
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study 203 (of 442) Swift AGN and Cluster Survey extended X-ray sources located in the SDSS DR8 footprint to search for galaxy over-densities in three-dimensional space using SDSS galaxy photometric redshifts and positions near the Swift cluster candidates. We find 104 Swift clusters with a >3{sigma} galaxy over-density. The remaining targets are potentially located at higher redshifts and require deeper optical follow-up observations for confirmation as galaxy clusters. We present a series of cluster properties including the redshift, brightest cluster galaxy (BCG) magnitude, BCG-to-X-ray center offset, optical richness, and X-ray luminosity. We also detect red sequences in ~85% of the 104 confirmed clusters. The X-ray luminosity and optical richness for the SDSS confirmed Swift clusters are correlated and follow previously established relations. The distribution of the separations between the X-ray centroids and the most likely BCG is also consistent with expectation. We compare the observed redshift distribution of the sample with a theoretical model, and find that our sample is complete for z<~0.3 and is still 80% complete up to z~0.4, consistent with the SDSS survey depth. These analysis results suggest that our Swift cluster selection algorithm has yielded a statistically well-defined cluster sample for further study of cluster evolution and cosmology. We also match our SDSS confirmed Swift clusters to existing cluster catalogs, and find 42, 23, and 1 matches in optical, X-ray, and Sunyaev-Zel'dovich catalogs, respectively, and so the majority of these clusters are new detections.
1876. SWIFT/BAT detections of AGN
ID:
ivo://CDS.VizieR/J/ApJ/633/L77
Title:
SWIFT/BAT detections of AGN
Short Name:
J/ApJ/633/L77
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present preliminary results from the first 3 months of the Swift Burst Alert Telescope (BAT) high Galactic latitude survey in the 14-195keV band. The survey reaches a flux of ~10^-11^erg/cm^2^/s and has ~2.7' (90% confidence) positional uncertainties for the faintest sources. This represents the most sensitive survey to date in this energy band. These data confirm the conjectures that a high-energy-selected active galactic nucleus (AGN) sample would have very different properties from those selected in other bands and that it represents a "true" sample of the AGN population. We have identified 86% of the 66 high-latitude sources. Twelve are Galactic-type sources, and 44 can be identified with previously known AGNs.
1877. Swift BAT 70 Month All-Sky Survey: 14\-20 keV: flux
ID:
ivo://nasa.heasarc/skyview/bat-flux-1
Title:
Swift BAT 70 Month All-Sky Survey: 14\-20 keV: flux
Short Name:
BAT-flux-1
Date:
25 Apr 2025
Publisher:
NASA/GSFC HEASARC
Description:
This BAT Hard X-ray Survey data is the 70-month survey product of the BAT instrument on the Swift observatory. Swift/BAT is a wide field-of-view (70x100 degrees) hard X-ray imager consisting of a coded mask and a large array of CdZnTe detectors (with an effective area of ~ 5000 cm<sup>2</sup>). <p> BAT is sensitive in the energy range 14-195 keV. The data are divided into 8 energy bands <table border> <tr><th>Band<th>Energy (keV)<th>Frequency (EHz) </tr> <tr><td>1<td> 14-20 <td> 3.38-4.84</tr> <tr><td>2<td> 20-24 <td> 4.84-5.80</tr> <tr><td>3<td> 24-35 <td> 5.80-8.46</tr> <tr><td>4<td> 35-50 <td> 8.46-12.1</tr> <tr><td>5<td> 50-75 <td> 12.1-18.1</tr> <tr><td>6<td> 75-100 <td> 18.1-24.2</tr> <tr><td>7<td> 100-150<td> 24.2-36.3</tr> <tr><td>8<td> 150-195<td> 36.3-47.2</tr> <tr><td>Sum (SNR only)<td>14-195<td> 3.38-47.2</tr> </table> Each band is represented as as two separate surveys, a signal-to-noise (SNR) map and a flux map. (e.g., BAT-snr-1 or BAT SNR 1 or BAT SNR 14-20, or BAT-Flux-1, ...). An additional summed survey, BAT-SNR-SUM or BAT SNR SUM or BAT SNR 14-195, is also available, but there is no summed flux survey. In our Web interface only the SNR surveys are shown in the Web form. Users can get flux maps corresponding to a given SNR image from the results pages. The batch interfaces may directly query any of the surveys since the user chooses the names explicitly rather than from a selection box. <p> The values displayed in the significance maps are the local signal to noise ratio in each pixel. The noise in these coded-mask images follows a Gaussian distribution with center at zero and a characteristic width (sigma) of 1.0. The noise is calculated locally for each pixel by measuring the RMS value of all pixel values in an annulus around each pixel and hence includs both statistical and systematic components. Known sources are excluded from the annuli. <p> The signal in each pixel is taken from the flux maps. <p> The flux values are in the native BAT survey units of counts/sec/detector. The detector is an individual piece of CZT in the BAT array with an area of 1.6 x 10<sup>-7</sup>m<sup>2</sub>. <p> While the Swift mission is primarily designed to follow gamma-ray bursts, the random distribution of bursts in the sky means that these survey's sky coverage is relatively uniform with the exposure at any point varying between about 6 to 16 megaseconds. The survey limits for source detection are about 10<sup>-11</sup> ergs/s/cm<sup>2</sup> over about half the sky and 1.3x10<sup>-11</sup> ergs/s/cm<sup>2</sup> over 90%. <p> These data replace the 9-month BAT datasets which we have retired. If you wish access to the older data please let us know. Note that for the 9-month data we provided access through the web page to the flux data and gave links to the signal-to-noise maps. Since the existence of sources is most easily seen in the SNR maps, we decided to invert that for this release. <p> For the 8 band data, the source data were provided by the BAT team as 6 FITS files. Each of these contained the 8 bands in separate image extensions for a region centered at l=0,b=+/-90 or l=0,90,180,270,b=0, the centers of 6 cubic facets. However these data are not the classical cube-faced projections, e.g., as used in COBE data. The data on the facets overlap, so that this is just a convenient way to tile the sky. <i>SkyView</i> separated each of the FITS image extensions into a separate file, but no other modifications were made to the data. The summed image was provided as six separate files. Provenance: NASA BAT Team. This is a service of NASA HEASARC.
1878. Swift BAT survey of AGNs
ID:
ivo://CDS.VizieR/J/ApJ/681/113
Title:
Swift BAT survey of AGNs
Short Name:
J/ApJ/681/113
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of the analysis of the first 9 months of data of the Swift BAT (Burst Alert Telescope) survey of AGNs in the 14-195keV band. Using archival X-ray data or follow-up Swift X-ray telescope (XRT) observations, we have identified 129 (103 AGNs) of 130 objects detected at |b|>15{deg} and with significance >4.8{sigma}. One source remains unidentified. These same X-ray data have allowed measurement of the X-ray properties of the objects.
1879. SwiftFT catalog
ID:
ivo://CDS.VizieR/J/A+A/528/A122
Title:
SwiftFT catalog
Short Name:
J/A+A/528/A122
Date:
21 Oct 2021
Publisher:
CDS
Description:
An accurate census of the active galactic nuclei (AGN) is a key step in investigating the nature of the correlation between the growth and evolution of super massive black holes and galaxy evolution. X-ray surveys provide one of the most efficient ways of selecting AGN.
1880. Swift-INTEGRAL X-ray (SIX) survey
ID:
ivo://CDS.VizieR/J/ApJS/201/34
Title:
Swift-INTEGRAL X-ray (SIX) survey
Short Name:
J/ApJS/201/34
Date:
21 Oct 2021
Publisher:
CDS
Description:
The supermassive black holes at the center of active galactic nuclei (AGNs) are surrounded by obscuring matter that can block nuclear radiation. Depending on the amount of blocked radiation, the flux from the AGN can be too faint to be detected by currently flying hard X-ray (above 15keV) missions. At these energies only ~1% of the intensity of the cosmic X-ray background (CXB) can be resolved into point-like sources that are AGNs. In this work, we address the question of undetected sources contributing to the CXB with a very sensitive and new hard X-ray survey: the Swift-INTEGRAL X-ray (SIX) survey, which is obtained with the new approach of combining the Swift/BAT and INTEGRAL/IBIS X-ray observations. We merge the observations of both missions, which enhances the exposure time and reduces systematic uncertainties. As a result, we obtain a new survey over a wide sky area of 6200deg^2^ that is more sensitive than the surveys of Swift/BAT or INTEGRAL/IBIS alone. Our sample comprises 113 sources: 86 AGNs (Seyfert-like and blazars), 5 galaxies, 2 clusters of galaxies, 3 Galactic sources, 3 previously detected unidentified X-ray sources, and 14 unidentified sources. The scientific outcome from the study of the sample has been properly addressed to study the evolution of AGNs at redshift below 0.4.

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