- ID:
- ivo://CDS.VizieR/J/MNRAS/454/1525
- Title:
- XMM-Newton and Chandra monitoring of Sgr A*
- Short Name:
- J/MNRAS/454/1525
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a study of the X-ray flaring activity of Sgr A* during all the 150 XMM-Newton and Chandra observations pointed at the Milky Way centre over the last 15 years. This includes the latest XMM-Newton and Chandra campaigns devoted to monitoring the closest approach of the very red Br{gamma} emitting object called G2. The entire data set analysed extends from 1999 September through 2014 November. We employed a Bayesian block analysis to investigate any possible variations in the characteristics (frequency, energetics, peak intensity, duration) of the flaring events that Sgr A* has exhibited since their discovery in 2001. We observe that the total bright or very bright flare luminosity of Sgr A* increased between 2013 and 2014 by a factor of 2-3 (~3.5{sigma} significance). We also observe an increase (~99.9 percent significance) from 0.27+/-0.04 to 2.5+/-1.0/d of the bright or very bright flaring rate of Sgr A*, starting in late summer 2014, which happens to be about six months after G2's pericentre passage. This might indicate that clustering is a general property of bright flares and that it is associated with a stationary noise process producing flares not uniformly distributed in time (similar to what is observed in other quiescent black holes). If so, the variation in flaring properties would be revealed only now because of the increased monitoring frequency. Alternatively, this may be the first sign of an excess accretion activity induced by the close passage of G2. More observations are necessary to distinguish between these two hypotheses.
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- ID:
- ivo://CDS.VizieR/J/ApJ/819/40
- Title:
- XMM-Newton brightest serendipitous sources
- Short Name:
- J/ApJ/819/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyzed a deep XMM-Newton observation of the radio-quiet {gamma}-ray PSR J2055+2539. The spectrum of the X-ray counterpart is nonthermal, with a photon index of {Gamma}=2.36+/-0.14 (1{sigma} confidence). We detected X-ray pulsations with a pulsed fraction of 25%+/-3% and a sinusoidal shape. Taking into account considerations on the {gamma}-ray efficiency of the pulsar and on its X-ray spectrum, we can infer a pulsar distance ranging from 450 to 750 pc. We found two different nebular features associated with PSR J2055+2539 and protruding from it. The angle between the two nebular main axes is ~162.8{deg}+/-0.7{deg}. The main, brighter feature is 12' long and <20" thick, characterized by an asymmetry with respect to the main axis that evolves with the distance from the pulsar, possibly forming a helical pattern. The secondary feature is 250"x30". Both nebulae present an almost flat brightness profile with a sudden decrease at the end. The nebulae can be fitted by either a power-law model or a thermal bremsstrahlung model. A plausible interpretation of the brighter nebula is in terms of a collimated ballistic jet. The secondary nebula is most likely a classical synchrotron-emitting tail.
- ID:
- ivo://CDS.VizieR/J/A+A/428/383
- Title:
- XMM-Newton Bright Serendipitous Survey
- Short Name:
- J/A+A/428/383
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present here "The XMM-Newton Bright Serendipitous Survey", composed of two flux-limited samples: the XMM-Newton Bright Source Sample (BSS, hereafter) and the XMM-Newton "Hard" Bright Source Sample (HBSS, hereafter) having a flux limit of fX~7x10^-14^erg/cm^2^/s in the 0.5-4.5keV and 4.5-7.5keV energy band, respectively. After discussing the main goals of this project and the survey strategy, we present the basic data on a complete sample of 400 X-ray sources (389 of them belong to the BSS, 67 to the HBSS with 56 X-ray sources in common) derived from the analysis of 237 suitable XMM-Newton fields (211 for the HBSS). At the flux limit of the survey we cover a survey area of 28.10 (25.17 for the HBSS) sq. deg. The extragalactic number-flux relationships (in the 0.5-4.5keV and in the 4.5-7.5keV energy bands) are in good agreement with previous and new results making us confident about the correctness of data selection and analysis.
- ID:
- ivo://nasa.heasarc/xmmbss
- Title:
- XMM-Newton Bright Serendipitous Survey
- Short Name:
- XMMBSS
- Date:
- 14 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- We present here the XMM-Newton Bright Serendipitous Survey, composed of two flux-limited samples: the XMM-Newton Bright Source Sample (BSS, hereafter) and the XMM-Newton "Hard" Bright Source Sample (HBSS, hereafter). The selection criteria for these two sample, 0.5 - 4.5 keV count rate >= 0.01 ct/s (BSS) and 4.5 - 7.5 keV count rate >= 0.002 ct/s (HBSS), correspond to a flux limit of f<sub>X</sub> ~ 7 x 10<sup>-14</sup> erg/cm<sup>2</sup>/s in the 0.5 - 4.5 keV and 4.5 - 7.5 keV energy bands, respectively, for sources with power-law spectra with energy spectral indices between 0.7 and 0.8. This table contains the basic data on a complete sample of 400 X-ray sources (389 of them belong to the BSS, 67 to the HBSS, with 56 X-ray sources in common) derived from the analysis of 237 suitable XMM-Newton fields (211 for the HBSS). At the flux limit of the survey, it covers a survey area of 28.10 (25.17 for the HBSS) square degrees. The extragalactic number-flux relationships (in the 0.5 - 4.5 keV and in the 4.5 - 7.5 keV energy bands) are in good agreement with previous and new results making the authors confident in the correctness of the data selection and their analysis. This table was created by the HEASARC in October 2006 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/428/383">CDS Catalog J/A+A/428/383</a> (the merger of files table3.dat and table4.dat). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/xmmbssagn
- Title:
- XMM-Newton Bright Serendipitous Survey: AGN X-Ray Spectral Properties
- Short Name:
- XMMBSSAGN
- Date:
- 14 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- X-ray surveys are a key instrument in the study of active galactic nuclei (AGN). Thanks to their penetrating ability, X-rays are able to map the innermost regions close to the central super massive black hole (SMBH) as well as to detect and characterize its emission up to high redshift. This table contains results from a detailed X-ray spectral analysis of the AGN belonging to the XMM-Newton Bright Serendipitous Survey (XBS, the HEASARC Browse XMMBSS table, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/IX/41">CDS Cat. IX/41</a>). The XBS is composed of two flux-limited samples selected in the complementary 0.5 to 4.5 and 4.5 to 7.5 keV energy bands and comprising more than 300 AGN up to redshift ~2.4. The authors have performed an X-ray analysis following two different approaches: by analyzing individually each AGN X-ray spectrum and by constructing average spectra for different AGN types. From the individual analysis, the authors find that there seems to be an anticorrelation between the spectral index and the sources' hard X-ray luminosity, such that the average photon index for the higher luminosity sources (>10<sup>44</sup> erg s<sup>-1</sup>) is significantly (>2 sigma) flatter than the average for the lower luminosity sources. They also find that the intrinsic column density distribution agrees with AGN unified schemes, although a number of exceptions are found (3% of the whole sample), which are much more common among optically classified type 2 AGN. The authors also find that the so-called "soft-excess", apart from the intrinsic absorption, constitutes the principal deviation from a power-law shape in AGN X-ray spectra and it clearly displays different characteristics, and likely a different origin, for unabsorbed and absorbed AGN. Regarding the shape of the average spectra, they find that it is best reproduced by a combination of an unabsorbed (absorbed) power law, a narrow Fe K-alpha emission line and a small (large) amount of reflection for unabsorbed (absorbed) sources. This table was created by the HEASARC in November 2011 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/530/A42">CDS Catalog J/A+A/530/A42</a> files table2.dat and table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/xmmcfrsoid
- Title:
- XMM-Newton/Canada-France Redshift Survey Fields Optical Identifications
- Short Name:
- XMM/CFRSID
- Date:
- 14 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the proposed identifications for all the good optical ID candidates (true probability value P' that the object is not associated of < 0.15) corresponding to the X-ray sources from the XMM-Newton surveys of the 3 and 14 hours Right Ascension (hereafter 3-h and 14-h, respectively) fields from the Canada-France Redshift Survey. (These fields are also known as the Groth Strip). The X-ray sources cover the 0.5 - 10 keV flux range from ~2 x 10<sup>-15</sup> - 10<sup>-13</sup> erg/cm<sup>2</sup>/s. The authors have used a subset of the XMM-Newton sources, which have Chandra positions, to determine the best method of obtaining optical identifications of sources with only XMM-Newton positions. They found optical identifications for 79% of the XMM-Newton sources for which there were deep optical images. The sources without optical identifications are likely to be optically fainter and have higher redshifts than the sources with identifications. The authors have estimated 'photometric redshifts' for the identified sources, calibrating their method using ~200 galaxies in the fields with spectroscopic redshifts. They find that the redshift distribution has a strong peak at z ~ 0.7. This table was created by the HEASARC in July 2005 based on the combination of CDS table J/MNRAS/350/785/tablea34.dat (the merged Tables A3 and A4 from the published paper) and CDS table J/MNRAS/350/785/tablea56.dat (the merged Tables A5 and A6 from the published paper). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/xmmcfrscat
- Title:
- XMM-Newton/Canada-France Redshift Survey Fields X-Ray Sources
- Short Name:
- XMM/CFRS
- Date:
- 14 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the X-ray source catalogs for the XMM-Newton surveys of the 3 and 14 hours Right Ascension (hereafter 3-h and 14-h, respectively) fields from the Canada-France Redshift Survey. (These fields are also known as the Groth Strip). The X-ray sources cover the 0.5-10 keV flux range from ~2 x 10<sup>-15</sup> - 10<sup>-13</sup> erg/cm<sup>2</sup>/s. The authors have used a subset of the XMM-Newton sources, which have Chandra positions, to determine the best method of obtaining optical identifications of sources with only XMM-Newton positions. They have found optical identifications for 79% of the XMM-Newton sources for which there were deep optical images. The sources without optical identifications are likely to be optically fainter and have higher redshifts than the sources with identifications. The authors have estimated 'photometric redshifts' for the identified sources, calibrating their method using ~200 galaxies in the fields with spectroscopic redshifts. They find that the redshift distribution has a strong peak at z~0.7. This table was created by the HEASARC in July 2005 based on CDS table J/MNRAS/350/785/tablea12.dat (the merged Tables A1 and A2 from the published paper). This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/A+A/655/A48
- Title:
- XMM-Newton catalogue of BL Lacs
- Short Name:
- J/A+A/655/A48
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- We present the results of the XMM-Newton catalogue of BL Lacs. X-ray and optical UV properties is presented based on the cross-correlation with the 1151 BL Lacs listed in the 5th edition of the Roma-BZCAT. The X-ray counterparts to these objects are searched in the field of view of all pointed observations in the XMM-Newton archive over nearly 20 years of mission. The cross-correlation yields a total of 310 XMM-Newton fields which correspond to 103 different BL Lacs. Data from the three EPIC cameras (X-ray) and OM (optical/UV) are homogeneously analysed using the XMM-Newton SAS software. Images, light curves and spectral products are produced for those BL Lacs detected in any of the three EPIC cameras. Two different phenomenological models, log parabola and power law, with different variations of the absorbing column density, are tested and their parameters extracted. Time variability information is derived from the light curves following well established statistical methods, and we quantify variability through statistical indicators. OM magnitudes and fluxes are computed when available.
- ID:
- ivo://nasa.heasarc/cfhtlsgxmm
- Title:
- XMM-Newton CFHTLS W1 Field Galaxy Groups Catalog
- Short Name:
- CFHTLSGXMM
- Date:
- 14 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a catalog of 128 X-ray galaxy groups, covering a redshift (z) range 0.04 < z <1.23, selected in the ~ 3 deg<sup>2</sup> part of the CFHTLS W1 field overlapping XMM-Newton observations performed under the XMM-LSS project. The authors carry out a statistical study of the redshift evolution out to redshift 1 of the magnitude gap between the first and the second brightest cluster galaxies of a well defined mass-selected group sample. They find that the slope of the relation between the fraction of groups and the magnitude gap steepens with redshift, indicating a larger fraction of fossil groups at lower redshifts. They also find that 22.2% +/- 6% of their groups at z <= 0.6 are fossil groups. The authors compare their results with the predictions of three semi-analytic models based on the Millennium simulation. The intercept of the relation between the magnitude of the brightest galaxy and the value of magnitude gap becomes brighter with increasing redshift. This trend is steeper than the model predictions which the authors attribute to the younger stellar age of the observed brightest cluster galaxies. This trend argues in favor of stronger evolution of the feedback from active galactic nuclei at z < 1 compared to the models. The slope of the relation between the magnitude of the brightest cluster galaxy and the value of the gap does not evolve with redshift and is well reproduced by the models, indicating that the tidal galaxy stripping, put forward as an explanation of the occurrence of the magnitude gap, is both a dominant mechanism and sufficiently well modeled. In this study, the authors analyzed the XMM-Newton observations of the CFHTLS wide (W1) field as a part of the XMM-LSS survey (Pierre et al., 2007, MNRAS, 382, 279). The details of the observations and the data reduction are presented in Bielby et al. (2010, A&A, 523, A66). The authors concentrate on the low-z counterparts of the X-ray sources and use all XMM-Newton observations performed until 2009, covering an area of 2.276 x 2.276 square degrees. The CFHTLS wide observations were carried out in the period between 2003 and 2008, covering an effective survey area of ~ 154 square degrees. The optical images and data of the CFHTLS were obtained with the MegaPrime instrument mounted on the CFHT in the five filters u*, g', r', i' and z'. This table was created by the HEASARC in December 2014 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/566/A140">CDS catalog J/A+A/566/A140</a> file table1.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/xcs
- Title:
- XMM-Newton Cluster Survey Catalog, DR1 Version
- Short Name:
- XCS
- Date:
- 14 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The XMM Cluster Survey (XCS) is a serendipitous search for galaxy clusters using all publicly available data in the XMM-Newton Science Archive. Its main aims are to measure cosmological parameters and trace the evolution of X-ray scaling relations. In their paper, the authors present the first data release from the XMM Cluster Survey (XCS-DR1). This consists of 503 optically confirmed, serendipitously detected, X-ray clusters. Of these clusters, 256 are new to the literature and 357 are new X-ray discoveries. They present 463 clusters with a redshift estimate (0.06 < z < 1.46), including 261 clusters with spectroscopic redshifts. The remainder have photometric redshifts. In addition, the authors have measured X-ray temperatures (kT<sub>X</sub>) for 401 clusters (0.4 < kT<sub>X</sub> < 14.7 keV). This table was created by the HEASARC in May 2013 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/423/1024">CDS Catalog J/MNRAS/423/1024</a> file xcsdr1.dat. This is a service provided by NASA HEASARC .
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