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2MASS LMC/SMC Calibration Merged Point Source Information Table
Photometric calibration for 2MASS was performed using observations of calibration fields made at regular intervals during each night of survey operations. Measurements of standard stars in the fields were used to derive the photometric zero point offsets as a function of time during each night. Atmospheric extinction coefficients were derived from 2MASS observations made over long periods.2MASS calibration fields, or tiles, are 1° long in declination and approximately 8.5' wide in right ascension. There are 35 regular survey calibration fields distributed at approximately two hour intervals in right ascension near declinations of approximately -30°, 0° and +30°. An additional five calibration fields were defined in and around the Large and Small Magellanic Clouds to support the deep observation (6x) campaign towards the end of survey operations.Over the course of the survey, the regular calibration fields were scanned between 562 and 3692 times in nominally photometric conditions. Equatorial fields were observed from both observatories, so were observed more frequently than those near ±30° which were observed with only one telescope. The special Magellanic Cloud calibration fields were observed 108 to 468 times between November 2000 and February 2001.The following table contains brief descriptions of the entries in the Survey, 6x and Calibration Merged Point Source Information Tables. The merged source tables contain the mean positions magnitudes and uncertainties for sources detected multiple times in each of the 2MASS data sets. The merging was carried out using an autocorrelation of the respective databases to identify groups of extractions that are positionally associated with each other, all lying within a 1.5" radius circular region. A number of confirmation statistics are also provided in the tables that can be used to test for source motion and/or variability, and the general quality of the merge.
M 83 Chandra X-Ray Point Source Catalog
The authors of this table have obtained a series of deep X-ray images of the nearby (4.61 Mpc) galaxy M 83 using Chandra, with a total exposure of 729 ks. Combining the new data with earlier archival observations totaling 61 ks, they find 378 point sources within the D<sub>25</sub> contour of the galaxy. The authors find 80 more sources, mostly background active galactic nuclei (AGNs), outside of the D<sub>25</sub> contour. Of the X-ray sources, 47 have been detected in a new radio survey of M 83 obtained using the Australia Telescope Compact Array (ATCA). Of the X-ray sources, at least 87 seem likely to be supernova remnants (SNRs), based on a combination of their properties in X-rays and at other wavelengths. The authors attempt to classify the point source population of M 83 through a combination of spectral and temporal analysis. As part of this effort, in the reference paper they carry out an initial spectral analysis of the 29 brightest X-ray sources. The soft X-ray sources in the disk, many of which are SNRs, are associated with the spiral arms, while the harder X-ray sources, mostly X-ray binaries (XRBs), do not appear to be. After eliminating AGNs, foreground stars, and identified SNRs from the sample, the authors construct the cumulative luminosity function (CLF) of XRBs brighter than 8 x 10<sup>35</sup> erg s<sup>-1</sup>. Despite M 83's relatively high star formation rate, the CLF indicates that most of the XRBs in the disk are low mass X-ray binaries (XRBs). The X-ray observations of M 83 in this survey were all carried out with the ACIS-S in order to maximize the sensitivity to soft X-ray sources, such as SNRs, and to diffuse emission. The nucleus of M 83 was centered in the field of the back-illuminated S3 chip to provide reasonably uniform coverage of M 83. In addition to the S3 chip, data were also obtained from chips S1, S2, S4, I2, and I3. All of the observations were made in the "very faint" mode to optimize background subtraction. Observations were spaced over a period of one year from 2010 December to 2011 December, as indicated in Table 1 of the reference paper. The only difference among observations was the roll orientation of the spacecraft and the differing exposure times. All of the observations were nominal, and yielded a total of 729 ks of useful data. In order to maximize their sensitivity and more importantly to improve their ability to identify time variable sources, the authors included in their analysis earlier Chandra observations of M 83 in 2000 and 2001 totaling 61 ks which were obtained by G. Rieke (Prop ID. 1600489) and by A. Prestwich (Prop ID. 267005758). These data were obtained in a very similar manner to that of the present survey, and increased the total exposure to 790 ks. The authors used ACIS EXTRACT (AE) to derive net count rates from the sources in various energy bands: 0.35 - 8.0 keV (total or T), 0.35 - 1.1 keV (soft or S), 1.1 - 2.6 keV (medium or M), 2.6 - 8.0 keV (hard or H), 0.5 - 2.0 keV ("normal" soft band) and 2.0 - 8.0 keV ("normal" hard band). Their choice of these bands was based on a variety of overlapping goals. The broad 0.35 - 8.0 keV band samples the full energy range accessible to Chandra observations. The three bands S, M and H provide energy ranges intended to classify sources on the basis of their hardness ratios. The boundary at 1.1 keV, in particular, is just above the region containing strong features due to Ne and Fe seen in the spectra of most SNRs. The 0.5 - 2.0 keV and 2.0 - 8.0 keV bands are needed because number counts of active galactic nuclei (AGNs) and of X-ray binary populations are normally carried out in these bands and because the 0.5 - 2.0 keV band, encompassing the peak of the response curve, provides better statistics for some purposes than S+M. The AE count rates were used to establish which of the sources in the candidate list were statistically valid. The authors retained any source that had a probability-of-no-source < 5 x 10<sup>-6</sup> in any one of these bands in the total data set. For their final run of AE, their list of source candidates had 847 potential sources. Of those, they find a total of 458 valid point sources, whose properties are listed in this table. Of the 458 point sources, 378 are located within the area defined by the D<sub>25</sub> ellipse of the galaxy (which the authors take to have a major axis diameter of 12.9 arcminutes), and the remaining 80 are outside this region. There were 43 sources in the nuclear region (defined to be any source within a projected radius of 0.5 kpc from the optical nucleus). This table was created by the HEASARC in July 2014 based on electronic versions of Tables 3, 4 and 5 from the reference paper which were obtained from the ApJS website. This is a service provided by NASA HEASARC .
NIMS RADIANCE POINT SPECTRA OF GASPRA V1.0
This data volume contains radiometrically corrected point spectra of asteroid 951 as acquired by the Galileo spacecraft Near Infrared Mapping Spectrometer (NIMS) on October 29, 1991. They record the spectra collected as the Galileo spacecraft approached the target asteroid. These data are products of the calibration of the raw data number files gap015tn.qub, gap035tn.qub, gap036tn.qub, gap037tn.qub, and gap038tn.qub (DATA SET ID ='GO-A-NIMS-3 TUBE-V1.0') with calibration factors acquired during the first Earth/Moon encounter of the Galileo mission. These raw data .qub files are archived in the Imaging Node of the NASA Planetary Data System (PDS). The calibrated spectra consist of radiance measurements for wavelengths between 0.7 - 5.2 micrometers.
IC 1396N Chandra X-Ray Point Source Catalog
The IC 1396N cometary globule (CG) within the large nearby HII region IC 1396 has been observed with the Advanced CCD Imaging Spectrometer (ACIS) detector on board the Chandra X-Ray Observatory on 2004 October 16.93 to 17.30. 117 X-ray sources are detected, of which ~ 50-60 are likely members of the young open cluster Trumpler 37 dispersed throughout the HII region, and 25 are associated with young stars formed within the globule. Infrared photometry (2MASS and Spitzer) shows that the X-ray population is very young: 3 older Class III stars, 16 classical T Tauri stars, and 6 protostars including a Class 0/I system. The authors infer a total T Tauri population of ~ 30 stars in the globule, including the undetected population, with a star formation efficiency of 1%-4%. An elongated source spatial distribution with an age gradient oriented toward the exciting star is discovered in the X-ray population of IC 1396N, supporting similar findings in other cometary globules. The geometric and age distribution is consistent with the radiation-driven implosion (RDI) model for triggered star formation in CGs by H II region shocks. The authors include only results arising from the imaging array (ACIS-I) of four abutted 1024 x 1024 pixel front-side illuminated CCDs covering about 17' x 17' on the sky. The aim point of the array was R.A. = 21h40m42.4s, Dec. = +58d1609.7" (J2000.0) or (l,b) = (100.0, + 4.2), and the satellite roll angle (i.e., orientation of the CCD array relative to the north-south direction) was 245.9 degrees. The total net exposure time of the observation is 30 ks with no background flaring due to solar activity or data losses. This table was created by the HEASARC in February 2009 based on the electronic version of Tables 1 and 2 from the paper which were obtained from the CDS (their catalog J/ApJ/654/316 files table1.dat and table2.dat). This is a service provided by NASA HEASARC .
M 71 Chandra X-Ray Point Source and Optical/Infrared Counterparts Catalog
The authors observed the nearby, low-density globular cluster M71 (NGC 6838) with the Chandra X-Ray Observatory to study its faint X-ray populations. Five X-ray sources were found inside the cluster core radius, including the known eclipsing binary millisecond pulsar (MSP) PSR J1953+1846A. The X-ray light curve of the source coincident with this MSP shows marginal evidence for periodicity at the binary period of 4.2hr. Its hard X-ray spectrum and luminosity resemble those of other eclipsing binary MSPs in 47 Tuc, suggesting a similar shock origin of the X-ray emission. A further 24 X-ray sources were found within the half-mass radius r<sub>h</sub>, reaching to a limiting luminosity of 1.5 x 10<sup>30</sup> ergs/s (0.3-8 keV). From a radial distribution analysis, the authors find that 18 +/- 6 of these 29 sources are associated with M71, somewhat more than predicted, and that 11 +/- 6 are background sources, both Galactic and extragalactic. M71 appears to have more X-ray sources in the range L<sub>X</sub> = 10<sup>30</sup> - 10<sup>31</sup> ergs/s than expected by extrapolating from other studied clusters using either mass or collision frequency. In their paper, the authors explore the spectra and variability of these sources and describe the results of ground-based optical counterpart searches. The authors obtained a 52.4 ks Chandra observation (ObsID 5434) of M71 (nominal center of cluster at J2000.0 RA and Dec of 19 53 46.1 +18 46 42) on 2004 December 20-21 using the Advanced CCD Imaging Spectrometer (ACIS) in very faint (VF), timed-exposure mode with a 3.141s frame time. They searched for X-ray sources in the observed field by employing techniques described in Tennant (2006, AJ, 132, 1372) which use a circular Gaussian approximation to the point-spread function (PSF). Within twice the M71 half-mass radius (r<sub>h</sub> = 1.65 arcminutes), they set the signal-to-noise threshold (S/N) for detection to 2.0, but also required the number of source counts to be at least 5 times the statistical uncertainty in the local background estimate. The empirical relation derived by Tennant, C<sub>min</sub> = (S/N)<sup>2</sup>/0.81, then implies a point-source sensitivity limit of about 4.9 counts for r<sub>M71</sub> <= 2r<sub>h</sub> and in the energy band 0.3-8.0 keV. Because of the increase in PSF size with off-axis distance and the associated increase in background within a detection cell, for R<sub>M71</sub> > 2r<sub>h</sub> they set the S/N threshold for detection to 2.4 and again required the number of source counts to be at least 5 times the statistical uncertainty in the local background estimate. The point-source sensitivity limit thus rises to about seven counts. This table contains 63 X-ray sources and their optical/infrared counterpart information, if any, for those sources with r<sub>M71</sub> <= 2r_h which are listed in Table 1 of the reference paper: these sources have name prefixes of s01 to s63. It also contains 73 X-ray sources and their optical/infrared counterpart information, if any, for those sources with r<sub>M71</sub> > 2r_h which are listed in Table 2 of the reference paper: these sources have name prefixes of ss01 to ss59 and is01 to is14. Each entry in this table corresponds to an X-ray source if there is no counterpart information or only a single identified counterpart or to a particular X-ray source and counterpart match if there are multiple counterpart identifications. There are thus 165 entries in this HEASARC table corresponding to 136 X-ray sources. This table was created by the HEASARC in March 2011 based on the electronic version of Tables 1 and 2 of the reference paper which were obtained from the CDS (their catalog J/ApJ/687/1019 files table1.dat and table2.dat). Some of the values for the alt_name parameter in the HEASARC's implementation of this table were corrected in April 2018. This is a service provided by NASA HEASARC .
ELAIS N1 and N2 Fields Chandra X-Ray Point Source Catalog
This table contains the results of an analysis of two deep (75 ks) Chandra observations of the European Large Area Infrared Space Observatory (ISO) Survey (ELAIS) fields N1 and N2 as the first results from the ELAIS deep X-ray survey. This survey is being conducted in well-studied regions with extensive multiwavelength coverage. This table contains the Chandra source catalogs along with an analysis of source counts and hardness ratios. A total of 233 X-ray point sources were detected in addition to two soft extended sources (not included in this table of point sources), which are found to be associated with galaxy clusters. An overdensity of sources is found in N1 with 30 per cent more sources than N2, which the authors attribute to large-scale structure. A similar variance is seen between other deep Chandra surveys. The source count statistics reveal an increasing fraction of hard sources at fainter fluxes. The number of galaxy-like counterparts also increases dramatically towards fainter fluxes, consistent with the emergence of a large population of obscured sources. The ELAIS Deep X-ray Survey (EDXS) is being conducted in the northern ELAIS regions N1 and N2. The Chandra data consist of approximately 75 ks exposures in each field. Region N1 was observed on 2000 August 3-4 (Obs_ID 888) and N2 on 2000 August 2-3 (Obs_ID 887). The nominal aimpoints were 16:10:20.11 +54:33:22.3 for N1, and 16:36:46.99 +41:01:33.7 for N2 in J2000.0 coordinates. The ACIS-I chips were used with the addition of the ACIS-S2 and ACIS-S4 chips. This table was created by the HEASARC in February 2007 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/343/293">CDS catalog J/MNRAS/343/293</a> files table1.dat and table2.dat. This is a service provided by NASA HEASARC .
M 17 Chandra X-Ray Point Source Catalog
This table contains some of the results from a Chandra ACIS observation of the stellar populations in and around the M17 H II region. The field reveals 886 sources (listed in the present table) with observed X-ray luminosities (uncorrected for absorption) between ~ 29.3 erg s<sup>-1</sup> < log L<sub>X</sub> < 32.8 erg s<sup>-1</sup>, 771 of which have stellar counterparts in infrared images. Spectral analysis results for the 598 brightest X-ray sources which have photometric significance of 2.0 or greater) are also given herein. For 546 of the X-ray sources, the fits used the "wabs(apec)" thermal plasma model in XSPEC assuming scaled 0.3 times solar photospheric abundances, while for the other 52 X-ray sources for which either the thermal model poorly described the data or required nonphysical parameters and the X-ray source was not identified with a known stellar counterpart, the fits used the "wabs(powerlaw)" model in XSPEC. In addition to the comprehensive tabulation of X-ray source properties, several other results were presented in the reference paper: 1. The X-ray luminosity function is calibrated to that of the Orion Nebula Cluster population to infer a total population of roughly 8000-10,000 stars in M17, one-third lying in the central NGC 6618 cluster. 2. About 40% of the ACIS sources are heavily obscured with A<sub>V</sub> > 10 mag. Some are concentrated around well-studied star-forming regions -- IRS 5/UC1, the Kleinmann-Wright Object, and M17-North -- but most are distributed across the field. As previously shown, star formation appears to be widely distributed in the molecular clouds. X-ray emission is detected from 64 of the hundreds of Class I protostar candidates that can be identified by near- and mid-infrared colors. These constitute the most likely protostar candidates known in M17. 3. The spatial distribution of X-ray stars is complex: in addition to the central NGC 6618 cluster and well-known embedded groups, we find a new embedded cluster (designated M17-X), a 2 pc long arc of young stars along the southwest edge of the M17 H II region, and 0.1 pc substructure within various populations. These structures may indicate that the populations are dynamically young. 4. All (14/14) of the known O stars but only about half (19/34) of the known B0-B3 stars in the M17 field are detected. These stars exhibit the long-reported correlation between X-ray and bolometric luminosities of L<sub>X</sub> ~ 10<sup>-7</sup> L<sub>bol</sub>. While many O and early-B stars show the soft X-ray emission expected from microshocks in their winds or moderately hard emission that could be caused by magnetically channeled wind shocks, six of these stars exhibit very hard thermal plasma components (kT > 4 keV) that may be due to colliding wind binaries. More than 100 candidate new OB stars are found, including 28 X-ray detected intermediate- and high-mass protostar candidates with infrared excesses. 5. Only a small fraction (perhaps 10%) of X-ray selected high- and intermediate-mass stars exhibit K-band-emitting protoplanetary disks, providing further evidence that inner disks evolve very rapidly around more massive stars. This table was created by the HEASARC in December 2007 based on electronic versions of Tables 1, 2, 3, 4 and 5 of the reference paper which were obtained from the electronic ApJ web site. This is a service provided by NASA HEASARC .
South Pole Telescope Sunyaev-Zeldovich Survey Point Source Catalog (2020)
This database table presents the catalog of emissive point-sources detected in the South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) survey, which is a contiguous 2530 deg<sup>2</sup> area surveyed between 2008-2011 in three bands centered at 95, 150, and 220 GHz. The catalog contains 4845 sources measured at a significance of 4.5 sigma or greater in at least one band, corresponding to detections above approximately 9.8, 5.8, and 20.4 mJy in 95, 150, and 220 GHz, respectively. Spectral behavior in the SPT bands is used for source classification into two populations based on the underlying physical mechanisms of compact, emissive sources that are bright at millimeter wavelengths: synchrotron radiation from active galactic nuclei and thermal emission from dust. The latter population includes a component of high-redshift sources often referred to as submillimeter galaxies (SMGs). In the relatively bright flux ranges probed by the survey, these sources are expected to be magnified by strong gravitational lensing. The survey also contains sources consistent with protoclusters, groups of dusty galaxies at high redshift undergoing collapse. The authors cross-match the SPT-SZ catalog with external catalogs at radio, infrared, and X-ray wavelengths and identify available redshift information. The catalog splits into 3980 synchrotron-dominated and 865 dust-dominated sources and determines a list of 506 SMGs. 10 sources are identified as stars. The SPT is a 10-m telescope located at the Amundsen-Scott South Pole station in Antarctica. At 150 GHz (2 mm), the SPT has arcminute angular resolution and a 1 deg<sup>2</sup> diffraction-limited field of view. The SPT was designed for high-sensitivity millimeter/sub-millimeter observations of faint, low-contrast sources, such as CMB anisotropies. The first survey with the SPT, designated as the SPT-SZ survey, was completed in 2011 November and covers a ~2500 deg<sup>2</sup> region of the southern extragalactic sky in three frequency bands, 95, 150, and 220 GHz, corresponding to wavelengths of 3.2, 2.0, and 1.4 mm. The fields were surveyed to depths of approximately 40, 18, and 70 microK arcmin at 95, 150, and 220 GHz, respectively. This study uses data from 19 fields observed by the SPT between 2008 and 2011. The fields are referred to using the J2000 coordinates of their centers, Right Ascension in hours and Declination in degrees. Table 1 in the reference paper lists the positions and effective areas of these fields.The total effective area used for the catalog and analysis in this present work is 2530 deg<sup>2</sup>. The catalog is an extension of two previous works: Vieira et al. (2010, ApJ, 719, 763) and Mocanu et al. (2013, ApJ, 779, 61) and builds on the same analysis pipeline, adding 1759 deg<sup>2</sup> of newly analyzed data, and additional data for two fields which were re-observed in 2010 and 2011. This table was originally created by the HEASARC in January 2014. It was updated to the 2020 version of this catalog in July 2020, based on a machine-readable catalog which was obtained from the <a href="https://lambda.gsfc.nasa.gov/product/spt/spt_everett2020_ps_catalog_info.cfm">LAMBDA</a> website. This is a service provided by NASA HEASARC .
M 101 Chandra X-Ray Point Source Catalog
A deep (98.2ks) Chandra Cycle 1 observation has revealed a wealth of discrete X-ray sources as well as diffuse emission in the nearby face-on spiral galaxy M 101. From this rich data set, the authors have created a catalog of the 110 sources from the S3 chip which were detected with a significance of greater than 3-sigma. This detection threshold corresponds to a flux of ~ 10<sup>-16</sup> ergs/cm<sup>2</sup>/s and a luminosity of ~ 10<sup>36</sup> ergs/s for a distance to M 101 of 7.2 Mpc. The sources display a distinct correlation with the spiral arms of M101 and include a variety of X-ray binaries, supersoft sources, supernova remnants, and other objects of which only ~27 are likely to be background sources. The 29 brightest sources have enough flux (greater than 100 counts) to perform at least crude spectral modeling using the HEASARC XSPEC model fitting program. Most of the sources could be satisfactorily fitted with a simple absorbed power-law spectrum model; however, eight of the softest sources were better fitted by an absorbed blackbody model. This table was created by the HEASARC in July 2007 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/561/189">CDS Catalog J/ApJ/561/189</a> files table1.dat and table4.dat. This is a service provided by NASA HEASARC .
NGC 2547 XMM-Newton X-Ray Point Source Catalog
This table contains a list of point sources detected by XMM-Newton EPIC in a pointing towards the young open cluster NGC 2547, made in order to allow the authors to characterize coronal activity in solar-type stars, and stars of lower mass, at an age of 30 Myr. X-ray emission was seen from stars at all spectral types, peaking among G stars at luminosities (0.3 - 3 keV) of L<sub>x</sub> ~= 10<sup>30.5</sup> erg/s and declining to L<sub>x</sub> <= 10<sup>29</sup> erg/s among M stars with masses >=0.2 solar masses. Coronal spectra show evidence for multi-temperature differential emission measures and low coronal metal abundances of Z~= 0.3. Most of the solar-type stars in NGC 2547 exhibit saturated or even supersaturated X-ray activity levels. The median levels of L<sub>x</sub> and L<sub>x</sub>/L<sub>bol</sub> in the solar-type stars of NGC 2547 are very similar to those in T-Tauri stars of the Orion Nebula cluster (ONC), but an order of magnitude higher than in the older Pleiades. The spread in X-ray activity levels among solar-type stars in NGC 2547 is much smaller than in older or younger clusters. This table contains the properties of those X-ray sources which are correlated with optical cluster members (see Section 2.2 of the reference paper for details on the correlation procedure that was adopted), as well as the properties of those X-ray sources which are uncorrelated with any optical cluster members. The table lists the cross-identifications with optical catalogs for the candidate cluster sources along with their X-ray luminosities and X-ray to bolometric flux ratios, as well as the correlations between cluster members which were detected by XMM-Newton and those detected 7 years earlier by the ROSAT HRI instrument, along with the X-ray luminosities and flux ratios as determined by the HRI. This table was created by the HEASARC in February 2007 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/367/781">CDS Catalog J/MNRAS/367/781</a> files table1.dat, table2.dat, table3.dat and table7.dat. This is a service provided by NASA HEASARC .
Spitzer Extragalactic First Look Survey MIPS 24 micron Point Source Catalog
The Extragalactic First Look Survey is composed of 4 square degrees of imaging with MIPS and IRAC centered at J1718+5930, with extensive ancillary data from ground-based optical and radio telescopes. As one of the first observations made with Spitzer after the completion of Science Verification at the end of 2003 November, the aim of this 67 hr survey was to characterize the extragalactic source populations observed with Spitzer down to sub-millijansky levels in the mid-infrared.
Fornax Dwarf Galaxy XMM-Newton X-Ray Point Source Catalog
This table contains some of the results of a deep archive XMM-Newton observation of the Fornax spheroidal galaxy that the authors analyzed with the aim of fully characterizing the X-ray source population (in most of the cases likely to be background active galactic nuclei) detected towards the target. A cross-correlation with the available databases allowed them to find a source that may be associated with a variable star belonging to the galaxy. The authors also searched for X-ray sources in the vicinity of the Fornax globular clusters GC 3 and GC 4 and found two sources probably associated with the respective clusters. The deep X-ray observation was also suitable for the search for the intermediate-mass black hole (of mass ~ 10<sup>4</sup> solar masses) expected to be hosted in the center of the galaxy. In the case of Fornax, this search is extremely difficult since the galaxy centroid of gravity is poorly constrained because of the large asymmetry observed in the optical surface brightness. Since the authors cannot firmly establish the existence of an X-ray counterpart of the putative black hole, they put constraints only on the accretion parameters. In particular, they found that the corresponding upper limit on the accretion efficiency, with respect to the Eddington luminosity, is as low as a few 10<sup>-5</sup>. This table was created by the HEASARC in February 2013 based on an electronic version of Table 1 from the reference paper which was obtained from the A&A web site. This is a service provided by NASA HEASARC .
Chandra ACIS GSG Point-Like X-Ray Source Catalog
The Chandra archival data are a valuable resource for various studies on different X-ray astronomy topics. In this paper, the authors utilize this wealth of information and present a uniformly processed data set, which can be used to address a wide range of scientific questions. The data analysis procedures are applied to 10,029 Advanced CCD Imaging Spectrometer observations, which produces 363,530 source detections belonging to 217,828 distinct X-ray sources. This number is twice the size of the Chandra Source Catalog (Version 1.1). The catalogs in this paper provide abundant estimates of the detected X-ray source properties, including source positions, counts, colors, fluxes, luminosities, variability statistics, etc. Cross-correlation of these objects with galaxies shows that 17,828 sources are located within the D<sub>25</sub> isophotes of 1,110 galaxies, and 7,504 sources are located between the D<sub>25</sub> and 2*D<sub>25</sub> isophotes of 910 galaxies. Contamination analysis with the log N-log S relation indicates that 51.3% of objects within 2*D<sub>25</sub> isophotes are truly relevant to galaxies, and the "net" source fraction increases to 58.9%, 67.3%, and 69.1% for sources with luminosities above 10<sup>37</sup>, 10<sup>38</sup>, and 10<sup>39</sup> erg/s, respectively. Among the possible scientific uses of this catalog mentioned in this paper, the authors discuss the possibility of studying intra-observation variability, inter-observation variability, and supersoft sources (SSSs). About 17,092 detected sources above 10 counts are classified as variable in individual observation with the Kolmogorov-Smirnov (K-S) criterion (P<sub>K-S</sub> < 0.01). There are 99,647 sources observed more than once and 11,843 sources observed 10 times or more, offering a wealth of data with which to explore their long-term variability. There are 1,638 individual objects (~2,350 detections) classified as SSSs. As a quite interesting subclass, detailed studies on X-ray spectra and optical spectroscopic follow-up are needed to categorize these SSSs and pinpoint their properties. In addition, this survey can enable a wide range of statistical studies, such as X-ray activity in different types of stars, X-ray luminosity functions in different types of galaxies, and multi-wavelength identification and classification of different X-ray populations. The ACIS observations were downloaded from the Chandra Data Archive on 2014 December 4, yielding 10,047 ACIS observations. Eighteen observations with PI as "Calibration" or Exposure as zero were excluded. Finally, there are 10,029 ACIS observations containing 4,146 ACIS-I observations and 5,883 ACIS-S observations in our sample. The exposure times for the selected observations cover a range from 50 s to 190 ks, with a total of 221,851 ks. This HEASARC table comprises the list of 218,789 X-ray point sources detected in the Chandra ACIS Survey and listed in the machine-readable version of Table 5 from the reference paper. This number is somewhat larger than the number of independent sources (217,828) stated in the abstract and Section 5 of the reference paper because if a source lies within 2*R<sub>25</sub> of more than one galaxy it is listed multiple times, once for each galaxy with which it may be associated. All parameters are the same for such duplicate cases except for the entry_number, alt_name, adopted_distance, luminosity, src_nucleus_offset, norm_src_nucleus_offset and (in some cases) source_type. This table was created by the HEASARC in March 2017 primarily based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/224/40/">CDS Catalog J/ApJS/224/40/</a> file table5.dat, the catalog of X-ray point sources in the Chandra ACIS Survey. The positional information for these sources was taken from <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/224/40/">CDS Catalog J/ApJS/224/40/</a> file table3.dat, the list of separation detections for these X-ray sources, using the first listed detection in each case. This is a service provided by NASA HEASARC .
NGC 253 XMM-Newton X-Ray Point Source Catalog
This table contains the NGC 253 XMM-Newton X-Ray Point Source Catalog. NGC 253 is a local, starbursting spiral galaxy with strong X-ray emission from hot gas, as well as many point sources. The authors have conducted a spectral survey of the X-ray population of NGC 253 using a deep XMM-Newton observation. NGC 253 only accounts for ~20 per cent of the XMM-Newton EPIC field of view, allowing them to identify ~ 100 X-ray sources that are unlikely to be associated with NGC 253. Hence, they were able to make a direct estimate of contamination from, for example, foreground stars and background galaxies. X-ray luminosity functions (XLFs) of galaxy populations are often used to characterize their properties. There are several methods for estimating the luminosities of X-ray sources with few photons. The authors have obtained spectral fits for the brightest 140 sources in the 2003 XMM-Newton observation of NGC 253, and compare the best-fitting luminosities of those 69 non-nuclear sources associated with NGC 253 with luminosities derived using other methods. They find the luminosities obtained from these various methods to vary systematically by a factor of up to 3 for the same data; this is largely due to differences in absorption. The authors therefore conclude that assuming Galactic absorption is probably unwise; rather, one should measure the absorption for the population. In addition, they find that standard estimations of the background contribution to the X-ray sources in the field are insufficient, and that the background active galactic nuclei (AGN) may be systematically more luminous than previously expected. However, the excess in their measured AGN XLF with respect to the expected XLF may be due to an as yet unrecognized population associated with NGC253. XMM-Newton observations are susceptible to periods of high background levels, caused by increased flux of solar particles. The authors screened the data from each of the EPIC cameras (MOS1, MOS2 and pn), to remove flaring intervals. This process resulted in ~ 46 ks of good time for the pn and ~ 69 ks for the MOS cameras. The authors combined the cleaned MOS and pn data, and ran the source detection algorithm provided with the XMM-Newton data analysis suite SAS version 7.0. They accepted sources with maximum-likelihood detections > 10 (equivalent to 4 sigma). This table was created by the HEASARC in April 2009 based on the electronic version of Tables A1 and A2 from the paper which were obtained from the CDS (their catalog J/MNRAS/388/849 files tablea1.dat and tablea2.dat). This is a service provided by NASA HEASARC .
47 Tuc Globular Cluster Chandra X-Ray Point Source Catalog (2017 Version)
The authors combined Chandra ACIS observations of the globular cluster 47 Tucanae (47 Tuc) from 2000, 2002, and 2014-2015 to create a deeper X-ray source list and study some of the faint radio millisecond pulsars (MSPs) present in this cluster. This work combined 180 ks of new Chandra ACIS data on 47 Tuc with 370 ks of archival data and used improved algorithms to generate a new source catalog, finding 81 new sources for a total of 370 within the half-mass region (2.79 arcsec) of the cluster. The majority of the newly identified sources are in the crowded core region, indicating cluster membership. The authors associated five of the new X-ray sources with chromospherically active BY Dra or W UMa variables identified by Albrow et al. (2001, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/559/1060">CDS Cat. <J/ApJ/559/1060></a>). See also the related <a href="gc47tuccxo.html">2005 source catalog</a>. This table was created by the HEASARC in September 2020 based upon the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/472/3706">CDS Catalog J/MNRAS/472/3706</a> files table2.dat, table4.dat, and table5.dat. The optical names from Albrow et al. (2001) were subsequently corrected in October 2020 in order to use the recommendation from the CDS Dictionary of Nomenclature of Celestial Objects. This is a service provided by NASA HEASARC .
Chamaeleon I North Cloud Chandra X-Ray Point Source Catalog
This table contains the Chamaeleon (Cha) I North Cloud Chandra X-Ray point source catalog. Sensitive X-ray imaging surveys provide a new and effective tool to establish the census of pre-main-sequence (PMS) stars in nearby young stellar clusters. A deep Chandra X-Ray Observatory (CXO) observation of PMS stars in the Chamaeleon I North cloud achieved a limiting total-band X-ray luminosity of log L<sub>t</sub> ~ 10<sup>27</sup> ergs/s (0.5 - 8 keV band) in a 0.8 x 0.8 pc<sup>2</sup> region. Of the 107 X-ray sources, 37 are associated with Galactic stars, of which 27 are previously recognized cloud members. These include 3 PMS brown dwarfs: the protostellar brown dwarf ISO 192 has a particularly high level of magnetic activity. Follow-up optical photometry and spectroscopy establish that 9-10 of the Chandra sources are probably magnetically active background stars. No new X-ray-discovered stars were confidently found despite the high sensitivity of the Chandra observation. From these findings, the authors argue that the sample of 27 PMS cloud members in the Chandra field is uncontaminated and complete down to K = 12 or a stellar mass of about 0.1 solar masses. A 16'x 16' region of the Cha I North cloud was observed with the imaging array of the Advanced CCD Imaging Spectrometer (ACIS-I) detector on board the Chandra X-Ray Observatory. The observation took place on 2001 July 2.25-3.04 UT with the detector aimpoint set at 11 10 00.0, -76 35 00 (J2000.0 RA and Declination). The effective exposure was 66.3 ksec. The authors also obtained VI-band CCD images of most of the ACIS field with the 1m telescope and CCD detector at the South African Astronomical Observatory (SAAO) during 2002 February. This table was created by the HEASARC in February 2007 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/614/267">CDS catalog J/ApJ/614/267</a> files table1.dat, table2.dat and table3.dat. This is a service provided by NASA HEASARC .
Spitzer South Ecliptic Pole MIPS 70 micron Point Source Catalog
The Spitzer/MIPS 24 and 70 μm imaging of an 11.5 square degree region near the South Ecliptic Pole (SEP) has been carried out in order to complement sub-millimeter wavelength observations (250-500 μm) of the same region of sky taken with the Balloon-borne Large Aperture Sub-millimeter Telescope (BLAST), with the goal of better characterizing the nature of sub-millimeter selected galaxies and their role in galaxy evolution. This field has also been extensively mapped at other wavelengths, and will be imaged from 100-500 μm as part of the Herschel Multi-tiered Extragalactic Survey (HerMES). Source detection and photometry were performed using the APEX software within the MOPEX package. Source candidates with S/N > 6 and reduced chi-squared values less than or equal to three (93% of the sources) are considered reliable detections. The remaining source candidates were then inspected (see Scott et al. 2010 for details) and false positives were removed from the catalog.
DEEP2 Galaxy Redshift Survey Fields Chandra Point Source Catalog
This table contains the X-ray point-source catalog produced from the Chandra Advanced CCD Imaging Spectrometer (ACIS-I) observations of the combined ~3.2 deg<sup>2</sup> DEEP2 (XDEEP2) survey fields, which consist of four ~ 0.7 - 1.1 deg<sup>2</sup> fields. The combined total exposures across all four XDEEP2 fields range from ~ 10 ks to 1.1 Ms. The authors detect X-ray point sources in both the individual ACIS-I observations and the overlapping regions in the merged (stacked) images. They find a total of 2976 unique X-ray sources within the survey area with an expected false-source contamination of ~ 30 sources (<~ 1%). In their paper, the authors present the combined log N-log S distribution of sources detected across the XDEEP2 survey fields and find good agreement with the Extended Chandra Deep Field and Chandra-COSMOS fields to f_(X,0.5-2keV)_ ~ 2 x 10<sup>-16</sup> erg cm<sup>-1</sup> s<sup>-1</sup>. Given the large survey area of XDEEP2, they additionally place relatively strong constraints on the log N-log S distribution at high fluxes (f_(X,0.5-2keV) ~ 3 x 10<sup>-14</sup> erg cm<sup>-1</sup> s<sup>-1</sup>), and find a small systematic offset (a factor ~ 1.5) toward lower source numbers in this regime, when compared to smaller area surveys. The number counts observed in XDEEP2 are in close agreement with those predicted by X-ray background synthesis models. Additionally, the authors present a Bayesian-style method for associating the X-ray sources with optical photometric counterparts in the DEEP2 catalog (complete to R<sub>AB</sub> < 25.2) and find that 2126 (~ 71.4% +/- 2.8%) of the 2976 X-ray sources presented here have a secure optical counterpart with a <~ 6% contamination fraction. The present table provides the DEEP2 optical source properties (e.g., magnitude, redshift) as part of the X-ray-optical counterpart catalog. This table was created by the HEASARC in October 2012 based on electronic versions of Tables 5 and 7 from the reference paper which were obtained from the ApJS web site. This is a service provided by NASA HEASARC .
NGC 1291 Chandra X-Ray Point Source Catalog
This table contains some of the results from a study of the X-ray binary (XRB) populations in the bulge and ring regions of the ring galaxy NGC 1291. Utilizing the four available Chandra observations totaling an effective exposure of 179 ks, the authors detect 169 X-ray point sources in the galaxy in the full band (0.3 - 8.0 keV) with a false-positive probability threshold of 10<sup>-6</sup> (implying approximately 2 false detections given the size of the image). Of these sources, 75 are in the bulge and 71 are in the ring. The authors report photometric properties of these sources in a point-source catalog. There are ~ 40% of the bulge sources and ~ 25% of the ring sources showing > 3-sigma long-term variability in their X-ray count rate. The X-ray colors suggest that a significant fraction of the bulge (~ 75%) and ring (~ 65%) sources are likely low-mass X-ray binaries (LMXBs). The spectra of the nuclear source indicate that it is a low-luminosity active galactic nucleus (AGN) with moderate obscuration; spectral variability is observed between individual observations. The authors construct 0.3-8.0 keV X-ray luminosity functions (XLFs) for the bulge and ring XRB populations, taking into account the detection incompleteness and background AGN contamination. They reach 90% completeness limits of ~ 1.5 x 10<sup>37</sup> and ~ 2.2 x 10<sup>37</sup> erg s<sup>-1</sup> for the bulge and ring populations, respectively. Both XLFs can be fit with a broken power-law model, and the shapes are consistent with those expected for populations dominated by LMXBs. In the paper, the authors perform detailed population synthesis modeling of the XRB populations in NGC 1291, which suggests that the observed combined XLF is dominated by an old LMXB population. They compare the bulge and ring XRB populations, and argue that the ring XRBs are associated with a younger stellar population than the bulge sources, based on the relative overdensity of X-ray sources in the ring, the generally harder X-ray color of the ring sources, the overabundance of luminous sources in the combined XLF, and the flatter shape of the ring XLF. This table was created by the HEASARC in May 2012 based on an electronic version of Table 2 from the reference paper obtained from the ApJ website. This is a service provided by NASA HEASARC .
Lupus 3 SFR XMM-Newton X-Ray Point Source Catalog
This table contains the analysis results of an XMM-Newton observation of the Lupus 3 region that contains a high proportion of young low-mass (< 0.3 solar masses) T Tauri stars in the Lupus star-forming complex. The observation had a ~22-ks effective exposure in the pn and MOS cameras. The detection of X-ray sources in 0.5 - 4.5 keV images of the Lupus 3 core was performed using the standard source detection method in the XMM-Newton Science Analysis Software (SAS). 102 candidate X-ray sources were detected with a likelihood threshold of >= 12 (corresponding to 4.4 sigma in Gaussian statistics) in the 30-arcmin diameter field-of-view of the EPIC cameras, of which 25 have visible or near-IR counterparts within the adopted 4" correlation radius for each X-ray source that were known to be pre-main sequence stars. Their X-ray luminosities range from 3 x 10<sup>28</sup> to 3 x 10<sup>30</sup> erg/s. This table gives the list of X-ray sources detected in the core of the Lupus 3 region with the EPIC camera on-board XMM-Newton, except that the X-ray source associated with the star HR 6000 (the nominal target of the XMM-Newton observation of the original PI) has been excluded. Additional information on the optical and IR counterparts of 25 of the X-ray sources, and on the X-ray spectra, is available in the reference paper. This table was created by the HEASARC in Match 2007 based on CDS table J/A+A/454/595 file table6.dat. This is a service provided by NASA HEASARC .
ScienceDex guides
Understand access before you commit
These curated guides explain access requirements, typical timelines, costs, and reuse considerations for widely used research datasets.
Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.