| Archive | List of EUVE Catalogs |
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This database table contains a detailed list of verified bright EUVE sources detected during the survey phase of the EUVE mission (calibration targets are also included). Two distinct surveys, the all-sky and deep surveys, were conducted by the four EUVE telescopes during the first six months of the mission. Further documentation is available through the HEASARC.
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 catalog of the EUVE Science Archive has been constructed based on information provided by personnel of the Center for Extreme-Ultraviolet Astrophysics (CEA), and is made available in the current EUVEMASTER database table. Most of the information in the catalog is also in the headers of the FITS files. The HEASARC now has nearly all of the 1378 pointed EUVE Deep Survey/Spectrometer (DS/S) datasets that were processed by CEA until its closing in March 2001. There are a small number of observations that were made in the year 2000 for which the HEASARC does not currently have the corresponding datasets. Notice that this catalog does not contain entries corresponding to EUVE observations in scan mode or where the files received by the HEASARC were not of the normal image or events type.
The Second Extreme Ultraviolet Explorer (EUVE) Right Angle Program (RAP) Catalog contains information on the detection of 235 extreme ultraviolet (EUV) sources, of which 169 are new detections, using the EUVE's RAP data. This catalog included observations made since the first EUVE RAP catalog (1994 January) and covered 17% 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/B), 200 A (Al/Ti/C), 400 A (Ti/Sb/Al or Dagwood), and 550 A (Sn/SiO). The EUVE RAP2 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 2% early-type stars, 45% late-type stars, 8% white dwarfs, 6% extragalactic objects, 24% with no firm classification, and 15% with no optical identification.
The All-Sky Catalog of Faint Extreme-Ultraviolet (EUV) Sources is a list of 534 objects detected jointly in the Extreme Ultraviolet Explorer (EUVE) (100 Angstrom (AA) band) All-Sky Survey and in the ROSAT X-ray Telescope (XRT) (0.25 keV band) All-Sky Survey. The joint selection criterion within a 1.5 arcminute positional tolerance permitted the use of a low count rate threshold in each survey. This low threshold was roughly 60% of the threshold used in the previous EUVE all-sky surveys, and 166 of the objects listed in this table were new EUV sources, appearing neither in the Second EUVE Source Catalog nor in the ROSAT Wide Field Camera Second Catalog. Preliminary identifications are offered for 105 of the 166 sources not previously reported in any EUV catalog: by far the most numerous (81) of the identifications are late-type (F-M) stars, while 18 are other stellar types, only 5 are white dwarfs, and none are extragalactic. The paucity of WDs and extragalactic objects may be explained by a strong horizon effect wherein interstellar absorption strongly limits the effective new-source search volume, and, thereby, selectively favors low-luminosity nearby sources over more luminous but distant objects. Notice that, with the adopted 1.5 arcminute acceptance criterion, about 50 spurious detections are expected.
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