- 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://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.
21585. XMM-Newton/2dF survey. II.
- ID:
- ivo://CDS.VizieR/J/MNRAS/349/135
- Title:
- XMM-Newton/2dF survey. II.
- Short Name:
- J/MNRAS/349/135
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we investigate the properties of low X-ray-to-optical flux ratio sources detected in a wide-area (2.5{deg}^2^) shallow [fX(0.5-8keV)~10^-14^erg/s/cm^2^] XMM-Newton survey. We find a total of 26 sources (5 per cent of the total X-ray-selected population) with log(fX)/f(opt)<-0.9 to the above flux limit. Optical spectroscopy is available for 20 of these low X-ray-to-optical flux ratio objects.
21586. XMM-Newton/2dF survey. IV.
- ID:
- ivo://CDS.VizieR/J/MNRAS/352/91
- Title:
- XMM-Newton/2dF survey. IV.
- Short Name:
- J/MNRAS/352/91
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of the X-ray spectral properties of 61 hard X-ray (2-8keV) selected sources from the bright XMM-Newton/2dF (f(2-8keV)>10^-14^erg/cm^2^/s) survey. This comprises nine XMMNewton pointings in the North Galactic Pole region (~1.6deg^2^) and overlaps with the SDSS, 2QZ and 2dFGRS surveys. Our sources contribute about 50 per cent of the 2-10keV X-ray background down to the flux limit of 10^-14^erg/cm^2^/s. The hardness ratio distribution of the sample suggests a deficit of heavily absorbed sources. Spectroscopic identifications exist for 34 sources.
- ID:
- ivo://CDS.VizieR/J/A+A/468/353
- Title:
- XMM-Newton Extended Survey of Taurus
- Short Name:
- J/A+A/468/353
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST) surveys the most populated ~5 square degrees of the Taurus Molecular Cloud, using the XMM-Newton X-ray observatory to study the thermal structure, variability, and long-term evolution of hot plasma, to investigate the magnetic dynamo, and to search for new potential members of the association. We present overall correlations with fundamental stellar parameters that were derived from the previous literature. The present overview paper introduces the project and provides the basic results from the X-ray analysis of all sources detected in the XEST survey. Comprehensive tables summarize the stellar properties of all targets surveyed. The survey goes deeper than previous X-ray surveys of Taurus by about an order of magnitude and for the first time systematically accesses very faint and strongly absorbed TMC objects. We find a detection rate of 85% and 98% for classical and weak-line T Tauri stars (CTTS resp. WTTS), and identify about half of the surveyed protostars and brown dwarfs. Overall, 136 out of 169 surveyed stellar systems are detected. We describe an X-ray luminosity vs. mass correlation, discuss the distribution of X-ray-to-bolometric luminosity ratios, and show evidence for lower X-ray luminosities in CTTS compared to WTTS.
- ID:
- ivo://CDS.VizieR/J/MNRAS/351/31
- Title:
- XMM-Newton Galactic Plane Survey (XGPS)
- Short Name:
- J/MNRAS/351/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results from the XMM-Newton Galactic Plane Survey (XGPS). In the first phase of the programme, 22 pointings were used to cover a region of approximately 3 deg^2^between 19{deg} and 22{deg} in Galactic longitude and +/-0.6{deg} in latitude. In total we have resolved over 400 point X-ray sources, at >=5{sigma} significance, down to a flux limit of ~2x10^-14^erg/s/cm^2^(2-10 keV).
- ID:
- ivo://CDS.VizieR/J/ApJ/794/48
- Title:
- XMM-Newton galaxy clusters X-ray properties
- Short Name:
- J/ApJ/794/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new X-ray temperatures and improved X-ray luminosity estimates for 15 new and archival XMM-Newton observations of galaxy clusters at intermediate redshift with mass and luminosities near the galaxy group/cluster division (M_2500_<2.4x10_70_^-1^M_{sun}_, L<2x10^44^erg/s, 0.3<z<0.6). These clusters have weak-lensing mass measurements based on Hubble Space Telescope observations of clusters representative of an X-ray-selected sample (the ROSAT 160SD survey). The angular resolution of XMM-Newton allows us to disentangle the emission of these galaxy clusters from nearby point sources, which significantly contaminated previous X-ray luminosity estimates for 6 of the 15 clusters. We extend cluster scaling relations between X-ray luminosity, temperature, and weak-lensing mass for low-mass, X-ray-selected clusters out to redshift ~0.45. These relations are important for cosmology and the astrophysics of feedback in galaxy groups and clusters. Our joint analysis with a sample of 50 clusters in a similar redshift range but with larger masses (M_500_<21.9x10^14^M_{sun}_, 0.15<=z<=0.55) from the Canadian Cluster Comparison Project finds that within r_2500_, M{prop.to}L^0.44+/-0.05^, T{prop.to}L^0.23+/-0.02^, and M{prop.to}T^1.9+/-0.2^. The estimated intrinsic scatter in the M-L relation for the combined sample is reduced to {sigma}_log(M|L)_=0.10, from {sigma}_log(M|L)_=0.26 with the original ROSAT measurements. We also find an intrinsic scatter for the T-L relation, {sigma}_log(T|L)_=0.07+/-0.01.
21590. XMM-Newton 13^H^ deep field
- ID:
- ivo://CDS.VizieR/J/MNRAS/362/1371
- Title:
- XMM-Newton 13^H^ deep field
- Short Name:
- J/MNRAS/362/1371
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a deep X-ray survey conducted with XMM-Newton, centred on the UK ROSAT 13^H^ deep field area. This region covers 0.18{deg}^2^, and is the first of the two areas covered with XMM-Newton as part of an extensive multi-wavelength survey designed to study the nature and evolution of the faint X-ray source population.
