- ID:
- ivo://nasa.heasarc/rcw38cxo
- Title:
- RCW 38 Chandra X-Ray Point Source Catalog
- Short Name:
- RCW38CXO
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the results of a 96.7-ks Chandra observation of one of the youngest, most embedded, and most massive young stellar clusters studied to this date in X-rays, namely the embedded young cluster, RCW 38. 460 X-ray sources were detected in the field, of which 360 are confirmed to be associated with the RCW 38 cluster. The cluster members range in luminosity from 10<sup>30</sup> to 10<sup>33.5</sup> erg/s. Over 10% of the cluster members with over 100 counts were found to exhibit flares, while about 15% of the cluster members with over 30 counts were variable. Of the sources identified as cluster members, 160 have near-infrared (NIR) counterparts either in the Two Micron All Sky Survey (2MASS) database or which were detected via Very Large Telescope observations. Of these, about 20% appear to have optically thick disks. An additional 353 cluster members were identified through NIR observations, of which at least 50% possess optically thick disks. Over 100 X-ray sources were fit as absorbed Raymond-Smith-type plasmas and the authors found that the column to the cluster members varies from 10<sup>21.5</sup> to 10<sup>23</sup> cm<sup>-2</sup>. Comparing the gas to dust absorption signatures in these stars they found N<sub>H</sub> = A<sub>V</sub> (2 x 10<sup>21</sup>) cm<sup>-2</sup>. They also found that the cluster contains 31 candidate OB stars and is centered about 10" (0.1 pc) west of the primary source of its ionization, the O5 star IRS 2. The cluster has a peak central density of about 400 X-ray sources pc<sup>-2</sup>. The authors estimate that the total cluster membership exceeds 2000 stars. The Chandra observation of RCW 38 took place on 2001 December 10-11 and lasted 96.7 ks. It used Advanced CCD Imaging Spectrometer (ACIS) chips 0, 1, 2, 3, 6 and 7 in very faint mode. The combined field of view (FOV) of the 4 chips in the imaging array (0-3, ACIS-I) is 16.9' x 16.9'. The aimpoint of the array was 8 59 19.20, -47 30 22.0 (J2000.0), and Chandra's roll angle was 51 degrees. The source detection algorithm PWDetect was run on the cleaned events list across the entire ACIS-I array, and found 460 sources, including 31 sources with more than 200 net counts, 49 sources with 100-200 net counts, 71 sources with 50-100 net counts, and 78 sources with 20-50 net counts. NIR matches were found for 349 of the 460 X-ray sources, including 294 of the 360 cluster members and 55 of the 100 nonmembers. This table was created by the HEASARC in February 2007 based on the merger of Tables 1, 10 and 11 from the reference paper which were obtained from the AJ website. It does not include the results from either the quartile analysis of the sources which were presented in Tables 2 and 3 or of the spectral analysis of some of the sources which were presented in Tables 5 through 9 of the reference paper. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/rcw108cxo
- Title:
- RCW 108 Star Formation Region Chandra X-Ray Point Source Catalog
- Short Name:
- RCW108CXO
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the results of an approximately 90 ks Chandra observation of a complex region that hosts multiple sites of recent and active star formation in ARA OB1a. The field is centered on the embedded cluster RCW 108-IR and includes a large portion of the open cluster NGC 6193. The authors detected over 420 X-ray sources in the field and combined these data with deep near-IR, Spitzer/IRAC and Midcourse Space Experiment (MSX) mid-IR data. They find that about 360 of the X-ray sources have near-IR counterparts. They divide the region into five parts based on the X-ray point source characteristics and extended 8 micron emission. The most clearly defined regions are the central region, identified by embedded sources with high luminosities in the both the near-IR and X-ray as well as high X-ray temperatures (~3 keV), and the eastern region, identified by low extinction and ~1 keV X-ray temperatures. Other regions, identified by their directional relationship to RCW 108-IR, are less uniform, representing combinations of the first two regions, independent star formation epochs, or both. The cluster members range in X-ray luminosity from 10<sup>29</sup> to 10<sup>33</sup> erg s<sup>-1</sup>. Over 18% of the cluster members with over 100 counts exhibit flares. All sources with over 350 counts are variable. Overall about 10% (16% in RCW 108-IR) appear to have optically thick disks as derived from their position in the (J - H), (H - K) diagram. The disk fraction becomes much higher when IRAC data are employed. The largest fraction of X-ray sources is best described as possessing some disk material via a more detailed extinction fitting. The authors fit the bulk of the X-ray spectra as absorbed Raymond-Smith-type plasmas, and find that the column to the RCW 108-IR members varies from 10<sup>21</sup> to 10<sup>23</sup> cm<sup>-2</sup>. They find that the field contains 41 candidate O or B stars, and estimate that the total number of pre-main-sequence stars in the field is about 1600 +/- 200. Approximately 800 are confined to the 3' (~1.1 pc) central region. The field was observed by Chandra on 2004 October 25 starting at 02:37 UT for 92.2 ks of total time and 88.8 ks of so-called "good-time" (ObsId 4503). The ACIS was used in the nominal imaging array (chips I0-I3) which provides a field of view of approximately 17' by 17' (~6.5 pc on a side). The aimpoint was at RA, Dec = 16:39:58.7, -48:51:54.4 (J2000.0). In addition, the S2 and S3 chips were on and located over IRAS 16379-4856. About 20 point sources were detected associated with this object; however, the analysis of these data is not presented here because they are far off-axis. This table was created by the HEASARC in June 2008 based on electronic versions of Tables 1, 2, 5, 7, 10 and 11 from the reference paper which were obtained from the Astronomical Journal web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rcw38yso
- Title:
- RCW 38 Young Stellar Objects Catalog
- Short Name:
- RCW38YSO
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the results from a study of the structure of the high-mass star-forming region RCW 38 and the spatial distribution of its young stellar population. Spitzer Infrared Array Camera (IRAC) photometry (3-8 micron) is combined with Two Micron All Sky Survey (2MASS) near-IR data to identify young stellar objects (YSOs) by IR-excess emission from their circumstellar material. Chandra X-ray data are used to identify class III pre-main-sequence stars lacking circumstellar material. The authors identify 624 YSOs: 23 class 0/I and 90 flat spectrum (FS) protostars, 437 class II stars, and 74 class III stars. They also identify 29 (27 new) O star candidates over the IRAC field. Seventy-two stars exhibit IR-variability, including 7 class 0/I and 12 flat spectrum YSOs. A further 177 tentative candidates are identified by their location in the IRAC [3.6] versus [3.6]-[5.8] color-magnitude diagram. The authors find strong evidence of subclustering in the region. Three subclusters were identified surrounding the central cluster, with massive and variable stars in each subcluster. The central region shows evidence of distinct spatial distributions of the protostars and pre-main-sequence stars. A previously detected IR cluster, DB2001_Obj36, has been established as a subcluster of RCW 38. This suggests that star formation in RCW 38 occurs over a more extended area than previously thought. The gas-to-dust ratio is examined using the X-ray derived hydrogen column density, NH and the K-band extinction, and found to be consistent with the diffuse interstellar medium, in contrast with Serpens and NGC 1333. The authors posit that the high photoionizing flux of massive stars in RCW 38 affects the agglomeration of the dust grains. This table contains the list of 624 young stellar objects (given in Tables 3 and 4 of the reference paper) found among the Spitzer sources in the field of RCW 38 using the two selection techniques described in Section 3 of the reference paper: (1) selection of stars with IR excesses in IR color-color diagrams, and (2) identification of X-ray luminous YSOs by comparing X-ray sources with IR detections. The latter technique was used to identify Type III YSOs lacking emission from a dusty disk. This table does NOT contain (i) the 177 candidate YSOs listed in Table 5 of the reference paper which were identified using the [3.6] versus [3.6] - [5.8] color-magnitude diagram, since contamination removal methods could not be utilized for these objects, (ii) the 24 candidate variable YSOs listed in Table 6 of the reference paper, nor (iii) 21 of the 29 candidate O-star cluster members which were listed in table 7 of the reference paper. This table was created by the HEASARC in January 2012 based on an electronic version of Tables 3 and 4 from the reference paper which were obtained from the ApJ web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ariel3a
- Title:
- 3rd Ariel-V SSI Catalog
- Short Name:
- ARIEL3A
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The 3rd Ariel-V SSI Catalog contains a list of X-ray sources detected by the University of Leicester's Sky Survey Instrument (SSI) on the Ariel-V satellite, and published (in 2 papers) as the Ariel-V (3A) Catalog: Warwick et al. 1981, MNRAS, 197, 865 (the low galactic latitude sources) and McHardy et al. 1981, MNRAS, 197, 893 (the high galactic latitude sources). The catalog is based on observations extending over a 5.5 year period from 1974 October until 1980 March. The SSI had a field of view of 0.75 by 10.6 degrees (FWHM) and had an energy range from 2 to 18 keV. A detailed description of the SSI is given by Villa et al. 1976, MNRAS, 176, 609. For a more detailed discussion of how the 3A Catalog was created, please refer to the Warwick et al. (1981) and McHardy et al. (1981) papers. This online catalog was created by the HEASARC in March 2003 based on the merger of two original tables originally obtained from the ADC website (<a href="https://heasarc.gsfc.nasa.gov/FTP/heasarc/dbase/misc_files/ariel3a/hilat.dat">https://heasarc.gsfc.nasa.gov/FTP/heasarc/dbase/misc_files/ariel3a/hilat.dat</a> and <a href="https://heasarc.gsfc.nasa.gov/FTP/heasarc/dbase/misc_files/ariel3a/lowlat.dat">https://heasarc.gsfc.nasa.gov/FTP/heasarc/dbase/misc_files/ariel3a/lowlat.dat</a>). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/revisedlhs
- Title:
- Revised Luyten Half-Second (LHS) Catalog
- Short Name:
- LuytenHS
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Revised Luyten Half-Second (LHS) Catalog contains refined coordinates and proper motion data for the high proper motion (HPM) stars listed in the Original Luyten Half-Second (LHS) catalog. The positional uncertainty in the Original LHS catalog is typically >10" and is often >30". The authors of the Revised LHS Catalog used the digital scans of the Palomar Observatory Sky Survey (POSS) I and POSS II plates to derive more accurate positions and proper motions for these objects. Out of the 4470 candidates in the LHS catalog, 4323 objects were manually re-identified in the POSS I and POSS II scans. A small fraction of the stars were not found due to the lack of finder charts and digitized POSS II scans. The uncertainties in the revised positions are typically ~2", but can be as high as ~8" in a few cases, which is a large improvement over the original data. Cross-correlation with the Tycho-2 and Hipparcos catalogs yielded 819 candidates (with red magnitude m_R <~12. For these brighter sources, the position and proper motion data were replaced with the more accurate Tycho/Hipparcos data. In total, there are revised proper motion measurements and coordinates for 4040 stars and revised coordinates for 4330 stars. This table was created by the HEASARC in October 2002 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/279">CDS Catalog I/279</a> (the 24-May-2002 version of the file catalog.dat). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rhessigrb
- Title:
- RHESSI Gamma-Ray Burst Catalog
- Short Name:
- RHESSIGRB
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors have studied statistically with respect to duration and hardness ratio a sample of 427 gamma-ray bursts (GRBs) measured by the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) satellite, a NASA Small Explorer satellite designed to study hard X-rays and gamma-rays from solar flares (Lin et al., 2002, Sol. Phys., 210, 3). Standard statistical tests were used, such as chi<sup>2</sup>, F-test, and the maximum likelihood ratio test, to compare the number of GRB groups in the RHESSI database with that of the BATSE database. The authors used the RHESSI GRB Catalog (Wigger et al., 2008, <a href="http://grb.web.psi.ch/">http://grb.web.psi.ch/</a>) and the Cosmic Burst List (Hurley, 2008, <a href="http://www.ssl.berkeley.edu/ipn3/masterli.html">http://www.ssl.berkeley.edu/ipn3/masterli.html</a>) to detect 487 GRBs in the RHESSI data over the time period between 2002 February 14 and 2008 April 25. For a deeper analysis, they chose a subset of 427 GRBs with data with a signal-to-noise ratio higher than 6. This table contains this subset. This HEASARC table was created in March, 2010, based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/498/399">CDS catalog J/A+A/498/399</a> file table7.dat. It was updated in September, 2019, with a minor change to the two GRB 051220 entries. Based on the literature, "A" and "B" suffixes were appended to make the names unique. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rhoophcxo
- Title:
- Rho Ophiuchi SFR Chandra X-Ray Point Source Catalog
- Short Name:
- RHOOPHCXO
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This catalog of X-ray sources represents some of the results of a systematic study of X-ray flares from low-mass young stellar objects, using two deep exposure Chandra observations of the main region of the rho Ophiuchi star-forming cloud. From 195 X-ray sources, including class I-III pre-main sequence sources and some young brown dwarfs, a total of 71 X-ray flares were detected. The Chandra X-ray Observatory (Weisskopf et al., 2002PASP..114....1W) observed the central region of rho Oph twice with a deep exposure of the ACIS-I array, consisting of four abutted X-ray CCDs. The first observation (here and after, obs. BF) covered the south-east 17.4' x 17.4' area, including cores B, C, E, and F, while the second observation (obs. A) covered the north-west area centered on core A (Loren et al., 1990ApJ...365..269L). This table contains data and the results of spectral and timing analyses on the 195 sources detected in the two rho Oph fields, 9 of which were detected in both fields and are therefore listed twice (A-61=BF-2, A-64=BF-4, A-65=BF-5, A-69=BF-7, A-75=BF-11, A-77=BF-15, A-78=BF-16, A-79=BF-17, and A-81 = BF-19). Sources which flared have multiple entries, with one entry (typically, but not always) listing the properties of the quiescent emission, and additional entries for individual flares which were analyzed separately. For the very faint sources for which the temperatures obtained from X-ray spectral analyses were not constrained, there are typically two entries in this table per source, one of which gives the results of a spectral analysis in which the temperature was fixed at 1 keV (11.6 MK) and the other in which the temperature was instead fixed at 5 keV (58 MK). Thus, there are more entries (306) in this HEASARC table than the number (195) of detected rho Oph X-ray sources. This table was created by the HEASARC in February 2007 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/PASJ/55/653">CDS Catalog J/PASJ/55/653</a> files table2.dat and table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ritterrbin
- Title:
- Ritter Binaries Related to CVs Catalog (7.21 Edition)
- Short Name:
- Ritter/Bin
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This HEASARC database table contains information on the so-called "Related Objects" only, as taken from the Catalog of Cataclysmic Binaries, Low-Mass X-ray Binaries, and Related Objects (7th Edition, Release 7.21, March 2014) of Ritter & Kolb. The complete catalog lists coordinates, apparent magnitudes, orbital parameters, stellar parameters of the components, and other characteristic properties of 1166 cataclysmic binaries, 105 low-mass X-ray binaries, and 500 related objects with known or suspected orbital periods. The HEASARC has for simplicity split this catalog into three Browse database tables, one for each class of objects: the present table (RITTERRBIN) containing the related binaries' data, a second one (<a href="/W3Browse/star-catalog/rittercv.html">RITTERCV</a>) containing cataclysmic binaries' data, and a third one (<a href="/W3Browse/star-catalog/ritterlmxb.html">RITTERLMXB</a>) containing the low-mass X-ray binaries' data. The literature published before 1 January 2014 has, as far as possible, been taken into account. Related objects are detached binaries consisting of either a white dwarf or a white dwarf precursor primary and of a low-mass secondary. The secondary may also be a highly evolved star. This table was last updated by the HEASARC in April 2014 based on the pcbdata.dat file from the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/B/cb">CDS Catalog B/cb</a>. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rittercv
- Title:
- Ritter Cataclysmic Binaries Catalog (7.21 Edition)
- Short Name:
- Ritter/CV
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This HEASARC database table contains information on cataclysmic binaries only, as taken from the Catalog of Cataclysmic Binaries, Low-Mass X-ray Binaries, and Related Objects (7th Edition, Release 7.21, March 2014) of Ritter & Kolb. The complete catalog lists coordinates, apparent magnitudes, orbital parameters, stellar parameters of the components, and other characteristic properties of 1166 cataclysmic binaries, 105 low-mass X-ray binaries, and 500 related objects with known or suspected orbital periods. The HEASARC has for simplicity split this catalog into three Browse database tables, one for each class of objects: the present table (RITTERCV) containing the cataclysmic binaries' data, a second one (<a href="/W3Browse/star-catalog/ritterlmxb.html">RITTERLMXB</a>) containing the low-mass X-ray binaries' data, and a third one (<a href="/W3Browse/star-catalog/ritterrbin.html">RITTERRBIN</a>) containing the related binaries' data. The literature published before 1 January 2014 has, as far as possible, been taken into account. Cataclysmic binaries are semi-detached binaries consisting of a white dwarf (or a white dwarf precursor) primary and a low-mass secondary which is filling its critical Roche lobe. The secondary is not necessarily unevolved, it may even be a highly evolved star, as, for example, in the case of the AM CVn-type stars. This table was last updated by the HEASARC in April 2014 based on the cbdata.dat file from the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/B/cb">CDS Catalog B/cb</a>. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ritterlmxb
- Title:
- Ritter Low-Mass X-Ray Binaries Catalog (7.21 Edition)
- Short Name:
- Ritter/LMXB
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This HEASARC database table contains information on low-mass X-ray binaries (LMXBs) only, as taken from the Catalog of Cataclysmic Binaries, Low-Mass X-ray Binaries, and Related Objects (7th Edition, Release 7.21, March 2014) of Ritter & Kolb. The complete catalog lists coordinates, apparent magnitudes, orbital parameters, stellar parameters of the components, and other characteristic properties of 1166 cataclysmic binaries, 105 low-mass X-ray binaries, and 500 related objects with known or suspected orbital periods. The HEASARC has for simplicity split this catalog into three Browse database tables, one for each class of objects: the present table (RITTERLMXB) containing the low-mass X-ray binaries' data, a second one (<a href="/W3Browse/star-catalog/rittercv.html">RITTERCV</a>) containing cataclysmic binaries' data, and a third one (<a href="/W3Browse/star-catalog/rittercv.html">RITTERRBIN</a>) containing the related binaries' data. The literature published before 1 January 2014 has, as far as possible, been taken into account. Low-mass X-ray binaries are semi-detached binaries consisting of either a neutron star or a black hole primary, and a low-mass secondary which is filling its critical Roche lobe. This table was last updated by the HEASARC in April 2014 based on the lmxbdata.dat file from the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/B/cb">CDS Catalog B/cb</a>. This is a service provided by NASA HEASARC .