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15121. 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.
15122. SwiftAGN&ClusterSurvey(SACS)Hard-Band(2-10keV)PointSourceCatalog
ID:
ivo://nasa.heasarc/sacshpscat
Title:
SwiftAGN&ClusterSurvey(SACS)Hard-Band(2-10keV)PointSourceCatalog
Short Name:
SACSHPSCAT
Date:
25 Apr 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Swift Active galactic nucleus (AGN) and Cluster Survey (SACS) uses 125 deg&lt;sup&gt;2&lt;/sup&gt; of Swift X-ray Telescope (XRT) serendipitous fields with variable depths surrounding gamma-ray bursts to provide a medium depth (4 x 10&lt;sup&gt;-15&lt;/sup&gt; erg cm&lt;sup&gt;-2&lt;/sup&gt; s&lt;sup&gt;-1&lt;/sup&gt;) and medium area survey filling the gap between deep, narrow Chandra/XMM-Newton surveys and wide, shallow ROSAT surveys. In the reference paper, a catalog of 22,563 point sources and 442 extended sources, and the number counts of the AGN and galaxy cluster populations are presented. 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. The authors use Wide-field Infrared Survey Explorer (WISE) mid-infrared(MIR) colors to classify the sources. For AGNs, they 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 (0.5-2.0 keV), but fewer MIR-blue sources in the hard X-ray band (2-8 keV). 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 followup observations of this cluster sample will significantly increase the number of higher redshift (z &gt; 0.5) X-ray-selected clusters. This HEASARC table contains the list of 10,060 Swift XRT point sources which were detected in the hard X-ray band image (2-10 keV) using wavdetect with a false positive threshold of 10&lt;sup&gt;-6&lt;/sup&gt; (contained in Table 3 of the reference paper). The authors consider these sources to be AGN candidates. This table was created by the HEASARC in June 2015 based on an electronic version of Table 3 of the reference paper, the list of Swift XRT point sources detected in the hard X-ray (2-10 keV) band, which was obtained from the ApJS web site. This is a service provided by NASA HEASARC .
15123. SwiftAGN&ClusterSurvey(SACS)Soft-Band(0.5-2keV)ExtendedSourceCatalog
ID:
ivo://nasa.heasarc/sacssescat
Title:
SwiftAGN&ClusterSurvey(SACS)Soft-Band(0.5-2keV)ExtendedSourceCatalog
Short Name:
SACSSESCAT
Date:
25 Apr 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Swift Active galactic nucleus (AGN) and Cluster Survey (SACS) uses 125 deg&lt;sup&gt;2&lt;/sup&gt; of Swift X-ray Telescope (XRT) serendipitous fields with variable depths surrounding gamma-ray bursts to provide a medium depth (4 x 10&lt;sup&gt;-15&lt;/sup&gt; erg cm&lt;sup&gt;-2&lt;/sup&gt; s&lt;sup&gt;-1&lt;/sup&gt;) and medium area survey filling the gap between deep, narrow Chandra/XMM-Newton surveys and wide, shallow ROSAT surveys. In the reference paper, a catalog of 22,563 point sources and 442 extended sources, and the number counts of the AGN and galaxy cluster populations are presented. 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. The authors use Wide-field Infrared Survey Explorer (WISE) mid-infrared(MIR) colors to classify the sources. For AGNs, they 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 (0.5-2.0 keV), but fewer MIR-blue sources in the hard X-ray band (2-8 keV). 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 followup observations of this cluster sample will significantly increase the number of higher redshift (z &gt; 0.5) X-ray-selected clusters. This HEASARC table contains the list of 442 Swift XRT extended sources which were detected in the soft X-ray band image (0.5-2 keV) and contained in Table 4 of the reference paper. The authors defined the extended source catalog as those sources with S/N &gt;= 4 and a minimum net photon count of 20 that are more than 3 sigma from the mean size of point sources for both their off-axis angle and S/N. The authors consider these extended sources to be candidate clusters of galaxies. This table was created by the HEASARC in July 2015 based on an electronic version of Table 4 of the reference paper, the list of Swift XRT extended sources detected in the soft X-ray (0.5-2 keV) band, which was obtained from the ApJS web site. This is a service provided by NASA HEASARC .
15124. SwiftAGN&ClusterSurvey(SACS)Soft-Band(0.5-2keV)PointSourceCatalog
ID:
ivo://nasa.heasarc/sacsspscat
Title:
SwiftAGN&ClusterSurvey(SACS)Soft-Band(0.5-2keV)PointSourceCatalog
Short Name:
SACSSPSCAT
Date:
25 Apr 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Swift Active galactic nucleus (AGN) and Cluster Survey (SACS) uses 125 deg&lt;sup&gt;2&lt;/sup&gt; of Swift X-ray Telescope (XRT) serendipitous fields with variable depths surrounding gamma-ray bursts to provide a medium depth (4 x 10&lt;sup&gt;-15&lt;/sup&gt; erg cm&lt;sup&gt;-2&lt;/sup&gt; s&lt;sup&gt;-1&lt;/sup&gt;) and medium area survey filling the gap between deep, narrow Chandra/XMM-Newton surveys and wide, shallow ROSAT surveys. In the reference paper, a catalog of 22,563 point sources and 442 extended sources, and the number counts of the AGN and galaxy cluster populations are presented. 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. The authors use Wide-field Infrared Survey Explorer (WISE) mid-infrared(MIR) colors to classify the sources. For AGNs, they 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 (0.5-2.0 keV), but fewer MIR-blue sources in the hard X-ray band (2-8 keV). 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 followup observations of this cluster sample will significantly increase the number of higher redshift (z &gt; 0.5) X-ray-selected clusters. This HEASARC table contains the list of 17,748 Swift XRT point sources which were detected in the soft X-ray band image (0.5-2.0 keV) using wavdetect with a false positive threshold of 10&lt;sup&gt;-6&lt;/sup&gt; (contained in Table 2 of the reference paper). The authors consider these sources to be AGN candidates. This table was created by the HEASARC in June 2015 based on an electronic version of Table 2 of the reference paper, the list of Swift XRT point sources detected in the soft X-ray (0.5-2 keV) band, which was obtained from the ApJS web site. This is a service provided by NASA HEASARC .
15125. SwiftAGN&ClusterSurvey(SACS)Total-Band(0.2-10keV)PointSourceCatalog
ID:
ivo://nasa.heasarc/sacstpscat
Title:
SwiftAGN&ClusterSurvey(SACS)Total-Band(0.2-10keV)PointSourceCatalog
Short Name:
SACSTPSCAT
Date:
25 Apr 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Swift Active galactic nucleus (AGN) and Cluster Survey (SACS) uses 125 deg&lt;sup&gt;2&lt;/sup&gt; of Swift X-Ray Telescope (XRT) serendipitous fields with variable depths surrounding gamma-ray bursts to provide a medium depth (4 x 10&lt;sup&gt;-15&lt;/sup&gt; erg cm&lt;sup&gt;-2&lt;/sup&gt; s&lt;sup&gt;-1&lt;/sup&gt;) and medium area survey filling the gap between deep, narrow Chandra/XMM-Newton surveys and wide, shallow ROSAT surveys. In the reference paper, a catalog of 22,563 point sources and 442 extended sources, and the number counts of the AGN and galaxy cluster populations are presented. 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. The authors use Wide-field Infrared Survey Explorer (WISE) mid-infrared(MIR) colors to classify the sources. For AGNs, they 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 (0.5-2.0 keV), but fewer MIR-blue sources in the hard X-ray band (2-8 keV). 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 followup observations of this cluster sample will significantly increase the number of higher redshift (z &gt; 0.5) X-ray-selected clusters. This HEASARC table contains the list of 22,563 Swift XRT point sources which were detected in the total X-ray band image (0.2-10 keV) using wavdetect with a false positive threshold of 10&lt;sup&gt;-6&lt;/sup&gt; (contained in Table 1 of the reference paper). The authors consider these sources to be AGN candidates. This table was created by the HEASARC in June 2015 based on an electronic version of Table 1 of the reference paper, the list of Swift XRT point sources detected in the total X-ray (0.2-10 keV) band, which was obtained from the ApJS web site. This is a service provided by NASA HEASARC .
15126. Swift/BAT AGN Spectroscopic Survey. I.
ID:
ivo://CDS.VizieR/J/ApJ/850/74
Title:
Swift/BAT AGN Spectroscopic Survey. I.
Short Name:
J/ApJ/850/74
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first catalog and data release of the Swift-BAT AGN Spectroscopic Survey. We analyze optical spectra of the majority of the detected AGNs (77%, 642/836) based on their 14-195keV emission in the 70-month Swift-BAT all-sky catalog. This includes redshift determination, absorption and emission-line measurements, and black hole mass and accretion rate estimates for the majority of obscured and unobscured AGNs (74%, 473/642), with 340 measured for the first time. With ~90% of sources at z<0.2, the survey represents a significant advance in the census of hard X-ray-selected AGNs in the local universe. In this first catalog paper, we describe the spectroscopic observations and data sets, and our initial spectral analysis. The FWHMs of the emission lines show broad agreement with the X-ray obscuration (~94%), such that Sy 1-1.8 have N_H_<10^21.9^cm^-2^, and Seyfert 2 have N_H_>10^21.9^cm^-2^. Seyfert 1.9, however, show a range of column densities. Compared to narrow-line AGNs in the SDSS, the X-ray-selected AGNs have a larger fraction of dusty host galaxies (H{alpha}/H{beta}>5), suggesting that these types of AGN are missed in optical surveys. Using the [OIII]{lambda}5007/H{beta} and [NII]{lambda}6583/H{alpha} emission-line diagnostic, about half of the sources are classified as Seyferts; ~15% reside in dusty galaxies that lack an H{beta} detection, but for which the upper limits on line emission imply either a Seyfert or LINER, ~15% are in galaxies with weak or no emission lines despite high-quality spectra, and a few percent each are LINERS, composite galaxies, H II regions, or in known beamed AGNs.
15127. Swift/BAT AGN spectroscopic survey. V. X-ray data
ID:
ivo://CDS.VizieR/J/ApJS/233/17
Title:
Swift/BAT AGN spectroscopic survey. V. X-ray data
Short Name:
J/ApJS/233/17
Date:
21 Oct 2021
Publisher:
CDS
Description:
Hard X-ray (>=10keV) observations of active galactic nuclei (AGNs) can shed light on some of the most obscured episodes of accretion onto supermassive black holes. The 70-month Swift/BAT all-sky survey, which probes the 14-195keV energy range, has currently detected 838 AGNs. We report here on the broadband X-ray (0.3-150keV) characteristics of these AGNs, obtained by combining XMM-Newton, Swift/XRT, ASCA, Chandra, and Suzaku observations in the soft X-ray band (<=10keV) with 70-month averaged Swift/BAT data. The nonblazar AGNs of our sample are almost equally divided into unobscured (N_H_<10^22^cm^-2^) and obscured (N_H_>=10^22^cm^-2^) AGNs, and their Swift/BAT continuum is systematically steeper than the 0.3-10keV emission, which suggests that the presence of a high-energy cutoff is almost ubiquitous. We discuss the main X-ray spectral parameters obtained, such as the photon index, the reflection parameter, the energy of the cutoff, neutral and ionized absorbers, and the soft excess for both obscured and unobscured AGNs.
15128. 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.
15129. Swift BAT gamma-ray burst durations
ID:
ivo://CDS.VizieR/J/ApJ/896/L20
Title:
Swift BAT gamma-ray burst durations
Short Name:
J/ApJ/896/L20
Date:
21 Mar 2022 07:00:25
Publisher:
CDS
Description:
The duration of a gamma-ray burst (GRB) is a key indicator of its physical origin, with long bursts perhaps associated with the collapse of massive stars and short bursts with mergers of neutron stars. However, there is substantial overlap in the properties of both short and long GRBs and neither duration nor any other parameter so far considered completely separates the two groups. Here we unambiguously classify every GRB using a machine-learning dimensionality reduction algorithm, t-distributed stochastic neighborhood embedding, providing a catalog separating all Swift GRBs into two groups. Although the classification takes place only using prompt emission light curves, every burst with an associated supernova is found in the longer group and bursts with kilonovae in the short, suggesting along with the duration distributions that these two groups are truly long and short GRBs. Two bursts with a clear absence of a supernova belong to the longer class, indicating that these might have been direct-collapse black holes, a proposed phenomenon that may occur in the deaths of more massive stars.
15130. Swift BAT Instrument Log
ID:
ivo://nasa.heasarc/swiftbalog
Title:
Swift BAT Instrument Log
Short Name:
SwiftBAT
Date:
25 Apr 2025
Publisher:
NASA/GSFC HEASARC
Description:
The BAT can operate several configuration modes simultaneously. Each of the simultaneous modes is listed in separate records within this table. For a given time interval, there are several records (partially overlapping in time), each describing a single configuration/mode. The BAT modes collect data for the entire FOV but also have the capability to record rates (tag mask rate) for up to a few specific sky positions (typically 3) that correspond to a pre-assigned target ID. It is possible that at least two or more of these positions do not coincide with the BAT or NFI pointing position and therefore the target ID does necessarily coincide with Target_ID of the BAT or NFI pointing position. This table records for the position (RA and Dec) and Target_ID parameters the correct values associated to each of the mask tag data. This database table is generated at the Swift processing site. During operation, it is updated on daily basis. This is a service provided by NASA HEASARC .

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