- ID:
- ivo://CDS.VizieR/J/ApJ/519/533
- Title:
- ROSAT observations of ACO clusters
- Short Name:
- J/ApJ/519/533
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled an X-ray catalog of optically selected rich clusters of galaxies observed by the Position Sensitive Proportional Counter (PSPC) during the pointed GO phase of the ROSAT mission. This paper contains a systematic X-ray analysis of 150 clusters with an optical richness classification of R>=2 from the Abell, Corwin, & Olowin (1989; ACO) catalog. All clusters were observed within 45' of the optical axis of the telescope during pointed PSPC observations. For each cluster, we calculate: the net 0.5-2.0keV PSPC count rate (or 4{sigma} upper limit) in a 1Mpc radius aperture, 0.5-2.0keV flux and luminosity, bolometric luminosity, and X-ray centroid. The cluster sample is then used to examine correlations between the X-ray and optical properties of clusters, derive the X-ray luminosity function of clusters with different optical classifications, and obtain a quantitative estimate of contamination (i.e., the fraction of clusters with an optical richness significantly overestimated due to interloping galaxies) in the ACO catalog.
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- ID:
- ivo://CDS.VizieR/J/A+A/311/384
- Title:
- ROSAT observations of BL Lacertae objects
- Short Name:
- J/A+A/311/384
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present soft X-ray spectra of 74 BL Lacertae objects observed with the PSPC detector on board of the ROSAT satellite. The sample contains all BL Lac objects detected during the pointed observation phase as a target or serendipitously. We have investigated the soft X-ray and broad band spectral properties and discuss the consequences for the X-ray emission processes. For the first time a clear dependence of the X-ray spectral steepness on the radio to X-ray spectral energy distribution is found: {alpha}_rx_ and {alpha}_x_ are correlated in the X-ray selected (XBL) subsample and anticorrelated in the radio selected (RBL) subsample. The objects with intermediate {alpha}_rx_ values thus do have the steepest soft X-ray spectra. Simulated PSPC spectra based on a set of simple two component multifrequency spectra are in good agreement with the measurements and suggest a broad range of synchrotron cutoff energies. We have calculated synchrotron self-Compton beaming factors for a subsample of radio bright objects and find a correlation of the beaming factors {delta}_IC_ with {alpha}_rx_ and {alpha}_x_. The most extreme RBL objects are very similar to flat spectrum radio quasars in all their broad band and X-ray properties.
- ID:
- ivo://CDS.VizieR/J/A+A/353/1044
- Title:
- ROSAT obs. of T Tauri stars in MBM 12
- Short Name:
- J/A+A/353/1044
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the ROSAT PSPC pointed and ROSAT All-Sky Survey (RASS, Cat. <IX/10>) observations and the results of our low and high spectral resolution optical follow-up observations of the T Tauri stars (TTS) and X-ray selected T Tauri star candidates in the region of the high galactic latitude dark cloud MBM 12 (L1453-L1454, L1457, L1458). Table 4 lists all of the X-ray detected sources in the direction of the molecular cloud MBM12 along with relevant X-ray and optical data.
- ID:
- ivo://nasa.heasarc/rosprspec
- Title:
- ROSAT Proposal Abstracts
- Short Name:
- ROSPRSPEC
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The ROSPRSPEC table contains the proposal titles and abstracts for all the accepted ROSAT proposals. Please refer to the ROSAO database table for other proposal information. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cmar1xray
- Title:
- ROSAT PSPC Catalog of Canis Major R1 X-Ray Sources
- Short Name:
- CMAR1XRAY
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The CMa R1 star-forming region contains several compact clusters as well as many young early-B stars. It is associated with a well-known bright rimmed nebula, the nature of which is unclear (fossil HII region or supernova remnant). To help elucidate the nature of the nebula, the authors' goal was to reconstruct the star-formation history of the CMa R1 region, including the previously unknown older, fainter low-mass stellar population, using X-rays. The authors analyzed images obtained with the ROSAT satellite, covering ~5 square degrees. Complementary VRI photometry was performed with the Gemini South telescope. Color-magnitude and color-color diagrams were used in conjunction with pre-main sequence evolutionary tracks to derive the masses and ages of the X-ray sources. The ROSAT images show two distinct clusters. One is associated with the known optical clusters near Z CMa, to which ~ 40 members are added. The other, which the authors name the "GU CMa" cluster, is new, and contains ~ 60 members. The ROSAT sources are young stars with masses down to M_star ~ 0.5 M_sun, and ages up to 10 Myr. The mass functions of the two clusters are similar, but the GU CMa cluster is older than the cluster around Z CMa by at least a few Myr. Also, the GU CMa cluster is away from any molecular cloud, implying that star formation must have ceased; on the contrary (as already known), star formation is very active in the Z CMa region. The two ROSAT observations that the authors analyzed are the following. By order of increasing RA, the first Field ('Field 1' hereafter), HEASARC ID RP201011 pointing axis RA(J2000} = 7<sup>h</sup> 00<sup>m</sup>, Dec(J2000) = -11<sup>o</sup> 30', has an exposure of 19.7 ks. 'Field 2', HEASARC ID RP201277, pointing axis RA(J2000) = 7<sup>h</sup> 04<sup>m</sup>, Dec(J2000) = -11<sup>o</sup> 33', has a much shorter exposure of 4.6 ks. This table contains the complete list of sources detected in CMa R1 by ROSAT. This online catalog was created by the HEASARC in April 2010 based on machine-readable tables obtained from the CDS (their catalog J/A+A/506/711, file tablea1.dat). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/lmcrosxray
- Title:
- ROSATPSPCCatalogofLMCX-RaySources(Haberl&Pietsch)
- Short Name:
- PSPC/LMC
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- More than 200 ROSAT PSPC observations performed between 1990 and 1994 in a 10 by 10 degree field centered on the Large Magellanic Cloud (LMC) have been analyzed on order to derive a catalogue of X-ray sources. The list contains 758 sources together with their X-ray properties. From cross-correlations of the PSPC catalogue with the SIMBAD data base and literature searches likely identifications are given in the paper from which this catalogue was derived (Haberl & Pietsch 1999, A&AS, 139, 277: Table 10) for 144 of these X-ray sources based on positional coincidence, but also taking into account X-ray properties like hardness ratios and source extent. Forty-six known sources are associated with supernova remnants and candidates in the LMC (SNRs: Haberl & Pietsch 1999, A&AS, 139, 277: Table 6), most of them already detected by previous X-ray missions. The number of known X-ray binaries in the LMC has increased to 17, and of supersoft sources to 9. The remaining ~50% of the identified sources comprise mainly foreground stars (up to 57) and background extragalactic objects (up to 15). This database was created at the HEASARC in June 2000 based on the ADC/<a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+AS/139/277">CDS Catalog J/A+AS/139/277</a>, and is derived from Table 1 of the reference. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/smcrosxry2
- Title:
- ROSAT PSPC Catalog of SMC X-Ray Sources (Haberl et al.)
- Short Name:
- PSPC/SMC2
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This is a catalogue of 517 discrete X-ray sources in a 6 degree by 6 degree field covering the Small Magellanic Cloud (SMC). The catalogue was derived from the pointed ROSAT PSPC observations performed between October 1991 and May 1994 and is complementary to the Large Magellanic Cloud (LMC) catalogue published by Haberl & Pietsch (1999, A&AS, 139, 277). The authors followed the same identification scheme and used, among other information, X-ray hardness ratios and spatial extent to classify unknown sources as candidates for active galactic nuclei (AGN), foreground stars, supernova remnants (SNRs), supersoft sources (SSSs) and X-ray binaries. In Table 7 of the paper from which this catalog is taken (Haberl et al. 2000, A&AS, 142, 41), for 158 of these 517 sources a likely source type is given, from which 46 sources are suggested as background AGN (including candidates resulting from a comparison of X-ray and radio images). Nearly all of the X-ray binaries known in the SMC were detected in the ROSAT PSPC observations; most of them with luminosities below 10<sup>36</sup> erg/s, suggesting that the fraction of high-luminosity X-ray binary systems in the Magellanic Clouds (MCs) is not significantly larger than in our galaxy. This database was created at the HEASARC in June 2000 based on the ADC/<a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+AS/142/41">CDS Catalog J/A+AS/142/41</a>, and is derived from Table 2 of the reference. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/galcenpspc
- Title:
- ROSAT PSPC Galactic Center Soft X-Ray Source Catalog
- Short Name:
- GALCENPSPC
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a catalog of 107 point-like X-ray sources derived from a systematic analysis of all the ROSAT PSPC observations of the Galactic Center region performed in 1992-1993. Besides Sgr A*, the massive black hole at the galactic center, 41 X-ray sources have been positionally associated with already classified objects. Twenty are identified with foreground stars and five with known Low Mass X-ray Binaries (LMXBs). The majority of the sources in this catalog still remains unidentified. They are hard and/or severely absorbed and probably represent a large population of X-ray binaries located in the galactic center region, accreting at low accretion rates, and still largely unknown. Analyses were performed in 4 different energy ranges: 0.1 - 2.4 keV (PSPC channels 8 - 240, the total energy band T), 0.1 - 0.4 keV (PSPC channels 8 - 40, the soft energy band S), 0.5 - 0.9 keV (PSPC channels 52 - 90, the medium energy band), and 0.9 - 2.4 keV (PSPC channels 91 - 240, the hard energy band H). A maximum likelihood method was applied to the merged photon lists in each band. Only a detection liklihood larger than 10 (corresponding to a probability of a chance detection smaller than e<sup>-10</sup>) was considered to be a true source. This table was created by the HEASARC in March 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/368/835">CDS Catalog J/A+A/368/835</a> file table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/m31rosxray
- Title:
- ROSAT PSPC M 31 Source Catalog
- Short Name:
- ROSAT/M31
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This catalog is the complete ROSAT PSPC Source List of X-ray sources found in two surveys of M 31 reported by Supper et al. (1997, 2001). These papers reported the results of the analysis of the two ROSAT PSPC surveys of M 31 performed in the summers of 1991 and 1992, respectively. summer 1992. Supper et al. (2001) compare and combine the results from the two surveys. In the first survey, 396 X-ray point sources were detected, and an identical number in the second survey, although this equality is coincidental, as the source lists are different and contain only 239 sources in common. Within the approximately 10.7 square degrees field of view of the second survey, 396 individual X-ray sources were detected, of which 164 sources were new detections. When combined with the first survey, this resulted in a total of 560 X-ray sources in the field of M 31. Their (0.1 keV-2.0 keV) fluxes range from 7 x 10<sup>-15</sup> to 7.6 x 10<sup>-12</sup> erg cm<sup>-2</sup> s<sup>-1</sup>, and of these 560 sources, 55 are tentatively identified with foreground stars, 33 with globular clusters, 16 with supernova remnants, and 10 with radio sources and galaxies (including M 32). A comparison with the results of the Einstein M 31 survey reveals 491 newly detected sources, 11 long-term variable sources, and 7 possible transient sources. Comparing the two ROSAT surveys, Supper et al. come up with 34 long-term variable sources and 8 transient candidates. For the M 31 sources, the observed X-ray luminosities range from 4 x 10<sup>35</sup> to 4 x 10<sup>38</sup> erg s<sup>-1</sup>. The total (0.1 keV-2.0 keV) luminosity of M 31 is (3.4 +/- 0.3) x 10<sup>39</sup> erg s<sup>-1</sup>, distributed approximately equally between the bulge and disk. Within the bulge region, the luminosity of a possible diffuse component combined with faint sources below the detection threshold is (2.0 +/- 0.5) x 10<sup>38</sup> erg s<sup>-1</sup>. An explanation in terms of hot gaseous emission leads to a maximum total gas mass of (1.0 +/- 0.3) x 10<sup>6</sup> solar masses. The conversion of PSPC count rates into X-ray fluxes depends on the assumed spectral shape. For M 31-sources, a power law with photon index of -2.0 and an intervening column density pf 9 x 10<sup>20</sup> H atoms cm<sup>-2</sup> may be used, leading to the conversion factor of 1 ct/ksec = 3.00 x 10<sup>-14</sup> erg cm<sup>-2</sup> s<sup>-1</sup> in the 0.1-2.0 keV broad band. For foreground stars, the application of this conversion factor leads to an over-estimate of the fluxes. This online catalog was created by the HEASARC in October 2001 based on machine-readable tables obtained from the ADC/CDS data centers (their catalog J/A+A/373/63, and table table6.dat). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ros400gcls
- Title:
- ROSAT PSPC 400 Square Degree Galaxy Cluster Catalog
- Short Name:
- ROS400GCLS
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This is a catalog of galaxy clusters detected in a new ROSAT PSPC survey. The survey is optimized to sample, at high redshifts, the mass range corresponding to T > 5 keV clusters at z = 0. Technically, our survey is the extension of the 160 square degree survey (160d, the HEASARC Browse table called ROSGALCLUS). The authors use the same detection algorithm, thus preserving the high quality of the resulting sample; the main difference is a significant increase in sky coverage. The new survey covers 397 square degrees and is based on 1610 high Galactic latitude ROSAT PSPC pointings, virtually all of the pointed ROSAT data that were suitable for the detection of distant clusters. The search volume for X-ray luminous clusters within z < 1 exceeds that of the entire local universe (z < 0.1). The authors detected 287 extended X-ray sources with fluxes f_x > 1.4 x 10^-13 erg s^-1 cm^-2 in the 0.5 - 2 keV energy band, of which 266 (93%) are optically confirmed as galaxy clusters, groups or individual elliptical galaxies. The paper from which this table is extracted provides a description of the input data, the statistical calibration of the survey via Monte Carlo simulations, and the catalog of detected clusters. The authors also therein compare the basic results with those from previous, smaller area surveys and find good agreement for the logN - log S distribution and the local X-ray luminosity function. This sample clearly shows a decrease in the number density for the most luminous clusters at z > 0.3. The comparison of these ROSAT-derived fluxes with the accurate Chandra measurements for a subset of high-redshift clusters demonstrates the validity of the 400 square degree survey's statistical calibration. This Browse table contains the main cluster catalog (Table 4 of the reference paper) which comprises 242 serendipitously detected clusters of galaxies. It does not include 24 clusters within a redshift of 0.01 of the redshift of the target of the ROSAT observation (given in Table 5 of the reference paper), as these latter are not entirely serendipitous, 5 noncluster extended sources (given in Table 6 of the reference paper), nor 16 likely false X-ray detections (given in Table 7 of the reference paper). This table was created by the HEASARC in December 2007 based on the machine-readable version of Table 4 (the 'Cluster Catalog') obtained from the electronic ApJ website. This is a service provided by NASA HEASARC .