- ID:
- ivo://nasa.heasarc/cargm31cxo
- Title:
- Carina Nebula Gum 31 Chandra X-Ray Point Source Catalog
- Short Name:
- CARGM31CXO
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Gum 31 is a prominent, but still rather poorly studied, HII region around the stellar cluster NGC 3324 at the northwestern periphery of the Carina nebula complex. The aim of the authors aim was to reveal and characterize the young stellar population in Gum 31. An X-ray survey is the only efficient way to identify young stars in this region, which has extremely high galactic field-star contamination, that can avoid the strong biases of infrared-excess-selected samples of disk-bearing young stars. The authors used the Chandra observatory to perform a deep (70 ks) X-ray observation of the Gum 31 region and detected 679 X-ray point sources. This extends and complements the X-ray survey of the central Carina nebula regions performed in the Chandra Carina Complex Project (CCCP, available in the HEASARC database system as the CARINACXO table). Using deep near-infrared images from their recent VISTA survey of the Carina nebula complex, their comprehensive Spitzer point-source catalog, and optical archive data, the authors identify counterparts for 75% of these X-ray sources. The aimpoint of the ACIS-I observation was set to be RA(J2000) = 10<sup>h</sup> 37<sup>m</sup> 36.6<sup>s</sup>, Dec(J2000) = -58<sup>o</sup> 41' 18". This position is close to the center of the H II region, and allows both the stellar cluster NGC 3324 and the cluster G286.38-0.26 to be in the inner parts of the field-of-view, where the point-spread function is still very good. The pointing roll angle (i.e., the orientation of the detector with respect to the celestial north direction) was 138.35<sup>o</sup>. The ACIS field-of-view is just wide enough to cover the full spatial extent of the optically bright Gum 31 H II region and some parts of the surrounding dust shell (see Fig. 1 of the reference paper). The ACIS-I field of view is 17' x 17', which corresponds to 11.3 p x 11.3 pc at the Gum 31 distance of 2.3 kpc). The total net exposure time of the observation was 68,909s (19.14 h). The details of the source detection procedures are described in Section 21. of the reference paper. The final X-ray catalog contains 679 individual point sources. The number of extracted counts ranges from 3 for the faintest sources, up to 920 for the strongest source, while the median value is 11 counts. This table contains the basic X-ray properties and near- and mid-infrared photometry of the X-ray sources detected in the Gum 31 field. The details of the IR matching to the X-ray sources are given in Sections 4.1, 4.2 and 4.3 of the reference paper. This table was created by the HEASARC in May 2014 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/564/A120">CDS Catalog J/A+A/564/A120</a> files table1.dat and table3.dat. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/cenacxo
- Title:
- Centaurus A Galaxy Chandra X-Ray Point Source Catalog
- Short Name:
- CENACXO
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the results from two Chandra X-ray Observatory observations of the X-ray point source population in the nearby radio galaxy Centaurus A (NGC 5128). Using a wavelet decomposition detection algorithm, 246 individual point sources are detected above a limiting luminosity of ~ 2 * 10<sup>36</sup> ergs/s, 82 of which are detected in both data sets where the fields of view overlap. Thirty-eight sources were detected in only one observation but were within the field of view of both pointings, implying considerable variability. Eight foreground stars were identified in these observations, and nine of the sources were identified with known globular clusters in Centaurus A. All previously observed ROSAT sources within our field of view were detected. The faintest source in this table has 5 counts, which corresponds to a limiting luminosity of ~2.2 x 10<sup>36</sup> erg/s at the center of the field of view. The two observations of Cen A were made with the ACIS-I array (observation IDs were 00316 and 00962) on 1999 December 5 and 2000 May 17, with 35.9 36.5 ks exposures, respectively. This table was created by the HEASARC in February 2007 based on CDS table J/ApJ/560/675 file table2.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cepbob3oid
- Title:
- Cep B/OB3 Star-Forming Region Chandra Point Source Optical/IR IDs Catalog
- Short Name:
- CEPBOB3OID
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Cepheus B (Cep B) molecular cloud and a portion of the nearby Cep OB3b OB association, one of the most active regions of star formation within 1 kpc, have been observed with the Infrared Array Camera (IRAC) detector on board the Spitzer Space Telescope. The goals were to study protoplanetary disk evolution and processes of sequential triggered star formation in the region. Out of ~400 pre-main-sequence (PMS) stars selected with an earlier Chandra X-ray Observatory observation, ~95% are identified with mid-infrared sources and most of these are classified as diskless or disk-bearing stars. The discovery of the additional >200 IR-excess low-mass members gives a combined Chandra+Spitzer PMS sample that is almost complete down to 0.5 * M<sub>sun</sub> outside of the cloud, and somewhat above 1 * M<sub>sun</sub> in the cloud. The X-ray observations of the Cep B/Cep OB3b region and their data analysis are described in detail by Getman et al. (2006, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/163/306">CDS Cat. J/ApJS/163/306</a>, HEASARC CEPBOB3CXO table). The 30 ks exposure was obtained on 2003 March 11.51-11.88 with the Advanced CCD Imaging Spectrometer (ACIS) detector on board the Chandra X-ray Observatory as part of the ACIS Instrument Team's Guaranteed Time Observations (ObsId No. 3502, P.I.: G. Garmire). The mid-IR observation of Cep B and Cep OB3b was obtained on 2007 February 18 with the IRAC detector on the Spitzer Space Telescope in the 3.6, 4.5, 5.8, and 8.0 micron channels. This was a General Observer project (program identification No. 30361; P.I.: J. Wang). This table contains the optical and infrared counterpart information on the 431 X-ray sources detected by Chandra. It does not contain the 224 IR-excess objects which were not detected as X-ray sources (listed in Table 3 of the reference paper) that are thought to be additional low-mass members of this complex. This table was created by the HEASARC in August 2011 primarily based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/699/1454">CDS catalog J/ApJ/699/1454</a> files table.dat and table 2.dat which list the optical and infrared counterpart information on the 431 X-ray sources detected by Chandra. The names and positions of these X-ray sources were taken from the Getman et al. (2006, ApJS, 163, 306) Catalog, which is available as the HEASARC Browse table CEPBOB3CXO. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cepbob3cxo
- Title:
- Cep B/OB3 Star-Forming Region Chandra X-Ray Point Source Catalog
- Short Name:
- CEPBOB3CXO
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the Cepheus B star formation region (the Cep B molecular cloud and the Cep OB3b OB association) Chandra X-Ray point source catalog. The Cepheus B (Cep B) molecular cloud and a portion of the nearby Cep OB3b OB association, one of the most active regions of star formation within 1 kpc, have been observed with the ACIS detector on board the Chandra X-Ray Observatory. 431 X-ray sources have been detected, of which 89% are confidently identified as clustered pre-main-sequence (PMS) stars. Two main results are obtained. First, the best census to date for the stellar population of the region has been made, with many members of two rich stellar clusters, the lightly obscured Cep OB3b association and the deeply embedded cluster in Cep B, whose existence was previously traced only by a handful of radio sources and T Tauri stars, being identified. Second, a discrepancy between the X-ray luminosity functions of the Cep OB3b and the Orion Nebula cluster has been found. This may be due to the different initial mass functions of the two regions (an excess of ~=0.3 M_solar stars) or different age distributions. Several other results are obtained. A diffuse X-ray component seen in the field is attributed to the integrated emission of unresolved low-mass PMS stars. The X-ray emission from HD 217086 (O7n), the principle ionizing source of the region, follows the standard model, involving many small shocks in an unmagnetized radiatively accelerated wind. X-ray source 294 joins a number of similar superflare PMS stars for which long magnetic structures may connect the protoplanetary disk to the stellar surface. The Chandra observation of Cep B and Cep OB3b was obtained on 2003 March 11.51-11.88 with the ACIS camera. Only results from the imaging array (ACIS-I) covering about 17' x 17' on the sky are considered here. The aim point of the array was 22 56 49.4 +62 39 55.6 (J2000.0 RA and Dec), and the satellite roll angle was 7.9 degrees. The total net exposure time was 30 ksec, with no background flaring or data losses. This table was created by the HEASARC in February 2007 based on the merger of electronic versions of tables 1, 2 and 3 from the above reference which were obtained from the ApJS website. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cg12cxo
- Title:
- CG 12 Chandra X-Ray Point Source Catalog
- Short Name:
- CG12CXO
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The mysterious high Galactic latitude cometary globule CG 12 has been observed with the ACIS detector on board the Chandra X-Ray Observatory. 128 X-ray sources are detected, of which half are likely young stars formed within the globule's head. This new population of >~ 50 T Tauri stars and one new embedded protostar is far larger than the previously reported few intermediate-mass and two protostellar members of the cloud. Most of the newly discovered stars have masses of 0.2-0.7 M<sub>solar</sub>, and 9% - 15% have K-band excesses from inner protoplanetary disks. X-ray properties provide an independent distance estimate consistent with the unusual location of CG 12 >~200 pc above the Galactic plane. The star formation efficiency in CG 12 appears to be 15% - 35%, far above that seen in other triggered molecular globules. The median photometric age found for the T Tauri population, assuming Siess et al. (2000, A&A, 358, 593) isochrones, is ~4 Myr with a large spread of <1 - 20 Myr and ongoing star formation in the molecular cores. The stellar age and spatial distributions are inconsistent with a simple radiation-driven implosion (RDI) model and suggest either that CG 12 is an atypically large shocked globule or that it has been subject to several distinct episodes of triggering and ablation. In their paper the authors report a previously unnoticed group of B-type stars northwest of CG 12 that may be the remnants of an OB association that produced multiple supernova explosions that could have shocked and ablated the cloud over a 15 - 30 Myr period. HD 120958 (B3e), the most luminous member of the group, may be currently driving an RDI shock into the CG 12 cloud. The current project combines four X-ray observations of the globule: <pre> Field ObsID Start Time Expo. R.A. Decl. Roll Angle (UT) (ks) (J2000.0) (deg) I.... 6423 2006 Apr 15 16:19:17 30.8 13 57 44.52 39 58 48.31 11.5 II... 6424 2006 Jun 02 07:25:09 3.1 13 57 42.87 39 43 01.76 285.0 III.. 6425 2006 Apr 13 08:44:08 3.1 13 56 19.40 39 42 47.94 14.7 IV... 6426 2006 Apr 15 12:54:20 3.1 13 56 19.40 39 58 48.09 11.1 </pre> where the units of right ascension are hours, minutes, and seconds, and the units of declination are degrees, arcminutes, and arcseconds, ObsID values are from the Chandra Observation Catalog, exposure times are the sum of Good Time Intervals (GTIs) for the CCD at the telescope aim point (CCD3) minus 1.3% to account for CCD readouts, and the aim points and roll angles are obtained from the satellite aspect solution before astrometric correction was applied. There is one primary field (I in Fig. 1 of the reference paper) with ~31 ks exposure directed at the globule's core and three secondary fields (II, III, and IV in Fig. 1) with ~3 ks exposures positioned contiguously to the north and west of the core. The primary pointing is intended to detect the population of pre-main sequence (PMS) stars forming in the molecular head of the globule. The secondary pointings are designed to locate an older population of stars expected if the present cloud is only the ablated remnant of a larger cloud that experienced sequential star formation triggering events, similar to the sequence of stars found in the authors' Chandra study of IC 1396N (Getman et al. 2007, ApJ, 654, 316, available in Browse as the IC1396NCXO table). Source searching was performed with data images and exposure maps constructed at three spatial resolutions (0.5", 1.0", and 1.4" pixel<sup>-1</sup>) using the CIAO wavdetect tool. The authors ran wavdetect with a low threshold P = 10<sup>-5</sup>, which is highly sensitive but permits false detections at this point in the analysis. This was followed by visual examination to locate other candidate sources, mainly close doubles and candidate sources near the detection threshold. Using ACIS Extract, photons were extracted within polygonal contours of ~90% encircled energy using position-dependent models of the PSF. The background was measured locally in source-free regions. Due to the very low, spatially invariant ACIS-I background in the Chandra observations of CG 12, there is a one-to-one correspondence between a source's significance and net counts. Following the procedure of Getman et al. (2007, ApJ, 654, 316), the list of candidate sources ws trimmed to omit sources with fewer than ~5 estimated source net counts, net full-band counts/PSF fraction <~ 4.5. In the case of the CG 12 observations, the above criterion is equivalent to accepting sources with a source significance of >~ 1.1. Thus, most of the statistically insignificant source candidates found during the wavdetect step were eliminated by the application of these source existence criteria. For Chandra sources with > 20 net counts, the authors performed spectral analysis with the XSPEC spectral fitting package version 12.2. The unbinned source and background spectra were fitted with one-temperature APEC plasma emission models using the maximum likelihood method. They assumed 0.3 times solar elemental abundances previously suggested as typical for young stellar objects (YSOs) in other star-forming regions. Solar abundances were taken from Anders & Grevesse (1989, Geochim. Cosmochim. Acta, 53, 197). X-ray absorption was modeled using the atomic cross sections of Morrison & McCammon (1983, ApJ, 270, 119). For absorbed thermal spectra characteristics of PMS stars, the absorption N<sub>H</sub> can be estimated to roughly a factor of 2 precision for 20 count sources. This table was created by the HEASARC in October 2010 based on the electronic versions of Tables 2, 3 and 4 from the paper which were obtained from the CDS (their catalog J/ApJ/673/331). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/chainthcxo
- Title:
- Chamaeleon I North Cloud Chandra X-Ray Point Source Catalog
- Short Name:
- CHAINTHCXO
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 .
- ID:
- ivo://nasa.heasarc/champhxagn
- Title:
- CHAMP (Chandra Multiwavelength Project) Hard X-Ray Emitting AGN
- Short Name:
- CHAMPHXAGN
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the results from an X-ray and optical analysis of 188 active galactic nuclei (AGN) identified from 497 hard X-ray (observed flux in the (2.0 - 8.0 keV) band > 2.7 x 10<sup>-15</sup> erg/cm<sup>2</sup>/s) sources in 20 Chandra fields (1.5 square degrees) forming part of the Chandra Multiwavelength Project (ChaMP). These medium-depth X-ray observations enable the detection of a representative subset of those sources responsible for the bulk of the 2 - 8 keV cosmic X-ray background. Brighter than the survey's optical spectroscopic limit, the authors achieve a reasonable degree of completeness (77% of X-ray sources with counterparts r' < 22.5 have been classified): broad emission-line AGNs (62%), narrow emission-line galaxies (24%), absorption-line galaxies (7%), stars (5%), or clusters (2%). To construct a pure AGN sample, the authors required the rest-frame 2.0-8.0 keV luminosity (uncorrected for intrinsic absorption) to exceed 10<sup>42</sup> erg s<sup>-1</sup>, thereby excluding any sources that may contain a significant stellar or hot ISM component. The most luminous known star-forming or elliptical galaxies attain at most L<sub>X</sub> = 10<sup>42</sup> erg s<sup>-1</sup>. Since many of the traditional optical AGN signatures are not present in obscured sources, high X-ray luminosity becomes the authors' single discriminant for supermassive black hole accretion. They believe that almost all of the NELGs and ALGs harbor accreting SMBHs based on their X-ray luminosity. They find that 90% of the identified ChaMP sources have luminosities above this threshold. These selection criteria yield a sample of 188 AGNs from 20 Chandra fields with f(2-8 keV) > 2.7 x 10<sup>-15</sup> erg cm<sup>-2</sup> s<sup>-1</sup>, r' < 22.5, and L<sub>X</sub> > 10<sup>42</sup> erg s<sup>-1</sup>. The authors removed five objects identified as clusters based on their extended X-ray emission. This table was created by the HEASARC in March 2007 based on the CDS table J/ApJ/618/123, file table4.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/chesscat
- Title:
- ChaMP Extended Stellar Survey (ChESS) X-Ray Catalog
- Short Name:
- CHESSCAT
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The ChaMP Extended Stellar Survey (ChESS) X-ray catalog contains 348 X-ray-emitting stars identified from correlating the Extended Chandra Multiwavelength Project (ChaMP), a wide-area serendipitous survey based on archival X-ray images, with the Sloan Digital Sky Survey (SDSS). The authors used morphological star/galaxy separation, matching to an SDSS quasar catalog, an optical color-magnitude cut, and X-ray data-quality tests to create this catalog, from a sample of 2121 matched ChaMP/SDSS sources. Their cuts retain 92% of the spectroscopically confirmed stars in the original sample while excluding 99.6% of the 684 spectroscopically confirmed extragalactic sources. Fewer than 3% of the sources in their final catalog are previously identified stellar X-ray emitters. For 42 catalog members, spectroscopic classifications are available in the literature. New spectral classifications and H-alpha measurements are presented for an additional 79 stars. The catalog is dominated by main-sequence stars; the authors estimate the fraction of giants in ChESS to be ~10%. They identify seven giant stars (including a possible Cepheid and an RR Lyrae star) as ChaMP sources, as well as three cataclysmic variables. They derive distances from ~10 to 2000 pc for the stars in the catalog using photometric parallax relations appropriate for dwarfs on the main sequence and calculate their X-ray and bolometric luminosities. These stars lie in a unique space in the L<sub>X</sub>-distance plane, filling the gap between the nearby stars identified as counterparts to sources in the ROSAT All Sky Survey and the more distant stars detected in deep Chandra and XMM-Newton surveys. For 36 newly identified X-ray-emitting M stars, the authors calculated L<sub>H-alpha</sub>/L<sub>bol</sub>. The quantities L<sub>H-alpha</sub>/L<sub>bol</sub> and L<sub>X</sub>/L<sub>bol</sub> are linearly related below L<sub>X</sub>/L<sub>bol</sub> ~ 3 x 10<sup>-4</sup>, while L<sub>H-alpha</sub>/L<sub>bol</sub> appears to turn over at larger L<sub>X</sub>/L<sub>bol</sub> values. Stars with reliable SDSS photometry have an ~0.1 mag blue excess in u-g, likely due to increased chromospheric continuum emission. Photometric metallicity estimates suggest that the sample is evenly split between the young and old disk populations of the Galaxy; the lowest activity sources belong to the old disk population, a clear signature of the decay of magnetic activity with age. This table was created by the HEASARC in January 2009 based on the electronic version of Tables 2 and 3 from the reference paper which were obtained from the ApJ web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/champlanex
- Title:
- ChaMPlane Galactic Bulge and Center X-Ray Source Catalog
- Short Name:
- CHAMPLANEX
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the Chandra Multiwavelength Plane (ChaMPlane) Survey catalog of X-ray point sources in the window and four Galactic bulge fields, specifically all source detections with net counts >= 1 in the 0.3-8 keV broad band. In the reference paper, the authors present the log N-log S and spatial distributions of X-ray point sources in seven Galactic bulge (GB) fields within 4 degrees of the Galactic center (GC). They compare the properties of 1159 X-ray point sources discovered in their deep (100 ks) Chandra observations of three low extinction Window fields near the GC with the X-ray sources in the other GB fields centered around Sgr B2, Sgr C, the Arches Cluster, and Sgr A* using Chandra archival data. To reduce the systematic errors induced by the uncertain X-ray spectra of the sources coupled with field-and-distance-dependent extinction, they classify the X-ray sources using quantile analysis and estimate their fluxes accordingly. The result indicates that the GB X-ray population is highly concentrated at the center, more heavily than the stellar distribution models. It extends out to more than 1.4 degrees from the GC, and the projected density follows an empirical radial relation inversely proportional to the offset from the GC. They also compare the total X-ray and infrared surface brightness using the Chandra and Spitzer observations of the regions. The radial distribution of the total infrared surface brightness from the 3.6-micron band images appears to resemble the radial distribution of the X-ray point sources better than that predicted by the stellar distribution models. Assuming a simple power-law model for the X-ray spectra, the closer to the GC, the intrinsically harder the X-ray spectra appear, but adding an iron emission line at 6.7 keV in the model allows the spectra of the GB X-ray sources to be largely consistent across the region. This implies that the majority of these GB X-ray sources can be of the same or similar type. Their X-ray luminosity and spectral properties support the idea that the most likely candidate is magnetic cataclysmic variables (CVs), primarily intermediate polars (IPs). Their observed number density is also consistent with the majority being IPs, provided the relative CV to star density in the GB is not smaller than the value in the local solar neighborhood. This table was created by the HEASARC in January 2010, based on the electronic version of Table 2 from the reference paper, which was obtained from the Astrophysical Journal web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cxogsgsrc
- Title:
- Chandra ACIS GSG Point-Like X-Ray Source Catalog
- Short Name:
- CXOGSGSRC
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 .
