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181. EUVE Right Angle Program, 3rd Catalog
ID:
ivo://nasa.heasarc/euverap3
Title:
EUVE Right Angle Program, 3rd Catalog
Short Name:
EUVERAP3
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Third Extreme Ultraviolet Explorer (EUVE) Right Angle Program (RAP) Catalog contains information on the detection of 76 extreme ultraviolet (EUV) sources, of which 63 are new detections, using the EUVE's RAP data. This catalog concentrates on observations made in the last years of the RAP, 1999 and 2000, with a sky coverage of 7% of the sky. The EUVE RAP used the all-sky survey telescopes (also known as "scanners"), which were mounted at right angles to the Deep Survey and Spectrometer instruments, to obtain photometric data in four wavelength bands centered at 100 Angstroms (Lexan/Boron or "Lexan"), 200 A (Al/Ti/C or "Al/C"), 400 A (Ti/Sb/Al or "Dagwood"), and 600 A (Sn/SiO or "Tin"). The EUVE RAP3 Catalog contains source count rates and probable source identifications from the available catalogs and literature. The source distribution is similar to previous EUV catalogs with 5 (8%) early-type stars, 23 (37%) late-type stars, 1 (2%) white dwarf, 1 (2%) cataclysmic variable, 4 (6%) extragalactic objects, 22 (35%) with no firm classification, and 7 (11%) with no optical identification. This final RAP Catalog, combined with the EUVE All-Sky Survey, the Lampton et al. (1997, ApJS, 108, 545) Faint EUV Source List, and previous RAP Catalogs, brings the total number of EUV sources to nearly 1200. This table was created by the HEASARC in September 2011 based on an ASCII version of Table 1 from the reference paper which was obtained from the AJ web site. This is a service provided by NASA HEASARC .
182. EUVE Right Angle Program, 1st Catalog
ID:
ivo://nasa.heasarc/euverap1
Title:
EUVE Right Angle Program, 1st Catalog
Short Name:
EUVERAP1
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This table contains the detections of 114 extreme-ultraviolet (EUV; 58 - 740 Angstrom) sources, of which 99 are new serendipitous sources, based on observations covering approximately 8% of the sky which were made with the imaging telescopes on board the Extreme Ultraviolet Explorer (EUVE) during the Right Angle Program (RAP). These data were obtained using the survey scanners and the Deep Survey instrument during the first year of the spectroscopic guest observer phase of the mission, from January 1993 to January 1994. The data set consists of 162 discrete pointings whose exposure times are typically two orders of magnitude longer than the average exposure times during the EUVE all-sky survey. Based on these results, the authors expect that EUVE will serendipitously detect approximately 100 new EUV sources per year, or about one new EUV source per 10 square degrees, during the guest observer phase of the EUVE mission. New EUVE sources of note include one B star and three extragalactic objects. The B star (HR 2875, EUVE J0729 - 38.7) is detected in both the Lexan/B (approximately 100 A) and Al/Ti/C (approximately 200 A) bandpasses, and the detection is shown not to be a result of UV leaks. The authors suggest that they are detecting EUV and/or soft x rays from a companion to the B star. Three sources, EUVE J2132+10.1, EUVE J2343-14.9, and EUVE J2359-30.6 are identified as the active galactic nuclei MKN 1513, MS2340.9-1511, and 1H2354-315, respectively. Some of the EUV sources have two or more alternative source identifications suggested for them in this catalog. Notice that, in such cases, the HEASARC has followed the structure of the original catalog as given in Table 2 of the reference paper, and lists separate entries for these alternative identifications. Thus, there are 152 entries in this database table, corresponding to 114 EUV sources. The characteristics of the 6 EUVE filters are listed in Table 1 of the reference paper (q.v.). This table was created by the HEASARC in February 2013 based on an electronic version of Table 2 from the reference paper which was supplied by Damian Christian (many thanks, Damian!) and extensively edited by the HEASARC, mostly to conform with the printed version. In 4 cases, the printed table was clearly incorrect, and a trailing 'B' from the alt_id_name was transposed to the type field. We have corrected these errors thus: <pre> Printed table As corrected in this table alt_id_name type alt_id_name type HD 22468 B ? HD 22468 B ? IDS 04199+1543 B ? IDS 04199+1543 B ? HD 29763 B ? HD 29763 B ? IDS 05264-0341 B ? IDS 05264-0341 B ? </pre> Because of the amount of hand-editing which was done, the user should treat the contents of this table with some caution and should cross-check its contents with the printed table. This is a service provided by NASA HEASARC .
183. EUVE Second Source Catalog
ID:
ivo://nasa.heasarc/euvecat2
Title:
EUVE Second Source Catalog
Short Name:
EUVE/2
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This is the 2nd Catalog of EUV objects detected by the Extreme Ultraviolet Explorer (EUVE) and published by Bowyer et al. in 1996 (ApJS, 102, 129). The data include (i) all-sky survey detections from the initial 6-months scanner survey phase, (ii) additional scanner detections made later during specially programmed observations designed to fill in low-exposure sky areas of the initial survey, (iii) sources detected with deep-survey telescope observations along the ecliptic plane, (iv) objects detected by the scanner telescopes during targeted spectroscopy observations, and (v) other observations. Plausible optical, X-ray, radio, and/or UV identifications are available for about 65% of the EUV sources. The EUVE all-sky survey detections (indicated by detect_mode = EASS in this catalog) comprise 514 detected EUV-emitting objects, the deep-survey detections (indicated by detect_mode = DS in this catalog) comprise 35 detected objects, and the sources detected during other phases of the mission (indicated by detect_mode = OTHER in this database) comprise 188 detected objects. Notice that 3 deep survey objects were also detected in the all-sky survey. Most of the sources detected in the other phases principally comprise those detected in deep exposures with the scanner telescopes as part of the Right Angle Program through December 24, 1994, or in long exposures with the deep survey instrument. Because these latter objects were observed with a variety of instruments and exposure strategies, the flux limits and detection thresholds vary over a wide range, and the Bowyer et al. reference should be consulted for more details. Some of the EUV sources have alternative cross-identifications at other wavelengths suggested for them. Notice that, in such cases, we have followed the original catalog and listed separate entries for each alternate identification. For example, the EUV-emitting object EUVE J1147+202 is listed twice, once with the suggested ID of DQ Leo, and a second time with the suggested ID of BD +21 2357. Thus, there are 801 entries in this database corresponding to 737 unique EUV sources. This is a service provided by NASA HEASARC .
184. EXOSAT/CMA High Galactic Latitude Survey
ID:
ivo://nasa.heasarc/exohgls
Title:
EXOSAT/CMA High Galactic Latitude Survey
Short Name:
EXOSAT/High
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
A survey of serendipitous source performed in the very soft X-ray band (0.05-2.0 keV) using the EXOSAT imaging telescopes is presented. The survey covers 783 square degrees of high galactic latitude sky and includes 210 serendipitous sources which define a complete (flux-limited) sample. An extensive program of optical and radio observatories together with cross-correlations with catalogs of known objects lead to the identification of 200 of the 210 detected sources. The 10 remaining objects have been preliminarily classified on the basis of their X-ray to optical flux ratios, thus making the sample essentially fully identified. Twenty-three additional serendipitous sources which did not satisfy the requirements for inclusion in the complete sample were also identified during the optical observations program. The complete sample has been used to study the logN-logS relation and the average spectral slope of AGN. It is found that the logN-logS slope is consistent with that of the Einstein Extended Medium Sensitivity Survey (EMSS) and with the "Euclidean" value of 1.5. The normalization of the logN-logS is a strong function of the assumed spectral slope of AGN. Consistency with the results of the EMSS implies that the average (energy) slope of extragalactic sources in the soft X-ray band is very steep (alpha ~ 1.5). An analysis of the association between AGN detection and Galactic NH also shows that alpha is steep and inconsistent with the canonical value of 0.7. The survey was particularly successful in detecting nearby Galactic soft X-ray emitters and includes a significantly higher percentage of stars than the Einstein EMSS, five White Dwarfs, and three previously unknown AM Her type systems. The sample of sources in this catalog has been selected from the CMA database, which it has been generated using a standard processing on the LE data. The source detection algorithm used a sliding cell method. The size of the search cell is such as to maximize the sensitivity across the field of view. For more information about the LE processing see the documentation in the CMA database. This is a service provided by NASA HEASARC .
185. EXOSAT/ME Galactic Plane Survey
ID:
ivo://nasa.heasarc/exogps
Title:
EXOSAT/ME Galactic Plane Survey
Short Name:
EXOSAT/Plane
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This catalog is based on information contained in Warwick et al (1988), MNRAS, 232, 551. The distribution of 2-6 keV x-ray emission in the galactic plane in the first and fourth galactic quadrants has been measured in a series of scanning observations with the medium-energy progportional counters on EXOSAT. The results are presented as contour maps and in the form of a catalogue of 70 discrete sources. Additional references can be found under the reference parameter. Additional information can be obtained upon request from the HEASARC. This is a service provided by NASA HEASARC .
186. EXOSAT ME Slew Catalog
ID:
ivo://nasa.heasarc/exms
Title:
EXOSAT ME Slew Catalog
Short Name:
EXOSAT/Slew
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This is the first online version of the EXMS catalog. It contains information on the 1210 sources detected by EXOSAT during slew manoevers between 1983 and 1986. Each detection was obtained by searching for excesses above the background level in the light curve, fitted with the expected triangular profile due to the source passing from one side of the collimator to the other. These light curves are available for inspection from the xray account at ESTEC/ESA (telnet :://xray@exosat.estec.esa.nl). The detection time, raw 1-8 keV count rate and position (based on the centroid of the uncertainty region) are given for all 1210 entries. 80% of entries have proposed single identifications, obtained by cross-correlation of the uncertainty region against other catalogs. For these sources, the count rates are also supplied after correction for collimator efficiency, normalised to counts/sec/half, where "half" refers to one half of the ME detector array. This ensures consistency with the entries in the ME database. Coordinates of the proposed counterpart are also given, together with object type. The remaining sources consist of cases where more than one plausible candidate lay within the uncertainty region or where no candidate could be found. For these cases, only raw count rates are supplied. This database is a modified copy of the exms databases available from ESTEC/ESA. It was re-built by the HEASARC in July 1999. This is a service provided by NASA HEASARC .
187. Extended Chandra Deep Field South 250-ks Improved Point Source Catalog
ID:
ivo://nasa.heasarc/ecdfsnew
Title:
Extended Chandra Deep Field South 250-ks Improved Point Source Catalog
Short Name:
ECDFSNEW
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This table contains the improved point-source catalog for the 250-ks Extended Chandra Deep Field-South (E-CDF-S) Survey, implementing a number of recent improvements in Chandra source-cataloguing methodology. For the E-CDF-S, the main catalog (entries from which are indicated with parameter values of source_sample = "Main" in this HEASARC representation) contains 1003 X-ray sources detected with wavdetect at a false-positive probability threshold of 10<sup>-5</sup> that also satisfy a binomial-probability source-selection criterion of P < 0.002. Such an approach maximizes the number of reliable sources detected: a total of 275 main-catalog sources are new compared to the Lehmer et al. (2005, ApJS, 161, 21) E-CDF-S main catalog. The authors also provide an E-CDF-S supplementary catalog that consists of 56 sources (entries from which are indicated with parameter values of source_sample = "Supp" in this HEASARC representation) detected at the same wavdetect threshold and having P of 0.002-0.1 and K<sub>s</sub> <= 22.3 mag counterparts. For all 1059 E-CDF-S sources, including the 318 newly detected ones (these being generally fainter and more obscured), the authors determine X-ray source positions utilizing centroid and matched-filter techniques; they also provide multi-wavelength identifications, apparent magnitudes of counterparts, spectroscopic and/or photometric redshifts, basic source classifications, and estimates of observed active galactic nucleus and galaxy source densities around respective field centers. Simulations show that the E-CDF-S main catalog is highly reliable and reasonably complete. Background and sensitivity analyses indicate that the on-axis mean flux limits reached represent a factor of ~1.5-2.0 improvement over the previous E-CDF-S limit. The 250-ks E-CDF-S is composed of four distinct and contiguous ~ 250-ks Chandra pointings that flank the CDF-S proper, consisting of a total of nine separate observations taken between 2004 February 29 and November 20 (see Lehmer et al., 2005, ApJS, 161, 21 for more details). This table was created by the HEASARC in August 2016 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/224/15">CDS Catalog J/ApJS/224/15</a> files table9.dat (the main source catalog) and table12.dat (the supplementary source catalog). This is a service provided by NASA HEASARC .
188. Extended Chandra Deep Field-South Optical and Near-IR Counterparts
ID:
ivo://nasa.heasarc/ecdfsoid2
Title:
Extended Chandra Deep Field-South Optical and Near-IR Counterparts
Short Name:
ECDFSOID2
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This table contains the results of a program to acquire high-quality optical spectra of X-ray sources detected in the Extended-Chandra Deep Field-South (E-CDF-S) and its central 2 Ms area. New spectroscopic redshifts, up to z = 4, are measured for 283 counterparts to Chandra sources with deep exposures (t ~ 2-9 hr per pointing) using multi-slit facilities on both VLT (VIMOS) and Keck (DEIMOS), thus bringing the total number of spectroscopically identified X-ray sources to over 500 in this survey field. Since their new spectroscopic identifications are mainly associated with X-ray sources in the shallower 250 ks coverage, the authors provide a comprehensive catalog of X-ray sources detected in the E-CDF-S including the optical and near-infrared counterparts, determined by a likelihood routine, and redshifts (both spectroscopic and photometric), that incorporate published spectroscopic catalogs, thus resulting in a final sample with a high fraction (80%) of X-ray sources having secure identifications. The authors demonstrate the remarkable coverage of the luminosity-redshift plane now accessible from their data while emphasizing the detection of active galactic nuclei (AGNs) that contribute to the faint end of the luminosity function (L<sub>0.5-8keV</sub> ~ 10<sup>43</sup> - 10<sup>44</sup> erg s<sup>-1</sup>) at 1.5 <~ z <~ 3, including those with and without broad emission lines. This redshift catalog includes 17 type-2 QSOs at 1 <~ z <~ 3.5 that significantly increases (doubles) such samples. Based on thei deepest (9 hr) VLT/VIMOS observation, the authors identify "elusive" optically faint galaxies (R<sub>mag</sub> ~ 25) at z ~ 2 - 3 based upon the detection of interstellar absorption lines (e.g., O II+Si IV, C II], C IV); in their paper, they highlight one such case, an absorption-line galaxy at z = 3.208 having no obvious signs of an AGN in its optical spectrum. In addition, they determine accurate distances to eight galaxy groups with extended X-ray emission detected both by Chandra and XMM-Newton. This online catalog was created by the HEASARC in November 2010 based on a machine-readable version of Table 4 from the paper which was obtained from the ApJ website. This is a service provided by NASA HEASARC .
189. Extended Chandra Deep Field-South Survey Optical Identifications Catalog
ID:
ivo://nasa.heasarc/ecdfsoid
Title:
Extended Chandra Deep Field-South Survey Optical Identifications Catalog
Short Name:
ECDFSOID
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
This table contains the first results of the authors' optical spectroscopy program aimed to provide redshifts and identifications for the X-ray sources in the Extended Chandra Deep Field South (ECDFS). A total of 339 sources (listed herein) were targeted using the IMACS spectrograph at the Magellan telescopes and the VIMOS spectrograph at the VLT. The authors have measured redshifts for 186 X-ray sources, including archival data and a literature search. They find that the active galactic nucleus (AGN) host galaxies have on average redder rest-frame optical colors than nonactive galaxies, and that they live mostly in the "green valley." The dependence of the fraction of AGNs that are obscured on both luminosity and redshift is confirmed at high significance and the observed AGN spatial density is compared with the expectations from existing luminosity functions. These AGNs show a significant difference in the mid-IR to X-ray flux ratio for obscured and unobscured AGNs, which can be explained by the effects of dust self-absorption on the former. This difference is larger for lower luminosity sources, which is consistent with the dust opening angle depending on AGN luminosity. This table was created by the HEASARC in April 2009 based on the electronic version of Table 2 from the Treister et al. (2009) paper obtained from the ApJ web site, except for the source positions which were taken from Virani et al. (2006). The full table from the latter paper is also available in Browse (the ECDFSCXO table). This is a service provided by NASA HEASARC .
190. Extended Chandra Deep Field-South X-Ray Point Source Catalog
ID:
ivo://nasa.heasarc/ecdfscxo
Title:
Extended Chandra Deep Field-South X-Ray Point Source Catalog
Short Name:
ECDFSCXO
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Extended Chandra Deep Field-South (ECDFS) survey consists of four Chandra X-Ray Observatory (CXO) ACIS-I pointings and covers ~1100 arcmin<sup>2</sup> (~0.3 deg<sup>2</sup>) centered on the original CDF-S field to a depth of approximately 228 ks. This is the largest Chandra survey ever conducted at such depth, and only one XMM-Newton survey reaches a lower flux limit in the hard 2.0-8.0 keV band. The authors detect 651 unique sources: 587 using a conservative source-detection threshold (identified by source_type = 'P' for primary source) and 64 (identified by source_type = 'S' for secondary source) using a lower source-detection threshold. These are combined in this HEASARC representation but were presented as two separate catalogs (Table 4 contained the primary sources, and Table 5 the secondary sources) in the original reference paper. Of the 651 total sources, 561 are detected in the full 0.5-8.0 keV band, 529 in the soft 0.5-2.0 keV band, and 335 in the hard 2.0-8.0 keV band. For point sources near the aim point, the limiting fluxes are approximately 1.7 x 10<sup>-16</sup> and 3.9 x 10<sup>-16</sup> ergs/cm<sup>2</sup>/s in the 0.5-2.0 and 2.0-8.0 keV bands, respectively. In their paper, the authors present the differential and cumulative flux distributions, which are in good agreement with the number counts from previous deep X-ray surveys and with the predictions from an active galactic nucleus (AGN) population synthesis model that can explain the X-ray background. In general, fainter sources have harder X-ray spectra, consistent with the hypothesis that these sources are mainly obscured AGNs. All nine observations of the ECDFS survey field were conducted with the Advanced CCD Imaging Spectrometer (ACIS) on board Chandra as part of the approved guest observer program in Cycle 5. Notice that Lehmer et al. (2005, ApJS, 161, 21) conducted a somewhat different analysis on these same data and obtained similar, but not identical results, e.g., Lehmer et al. found 809 total X-ray sources compared to 651 in the present table. This table was created by the HEASARC in April 2009 based on the electronic versions of Tables 4 and 5 from the paper which were obtained from the CDS (their catalog J/AJ/131/2373 files table4.dat and table5.dat). This is a service provided by NASA HEASARC .