- ID:
- ivo://CDS.VizieR/J/A+A/457/501
- Title:
- XMM-Newton survey of the ELAIS-S1 field
- Short Name:
- J/A+A/457/501
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The formation and evolution of cosmic structures can be probed by studying the evolution of the luminosity function of the Active Galactic Nuclei (AGNs), galaxies and clusters of galaxies and of the clustering of the X-ray active Universe, compared to the IR-UV active Universe. To this purpose, we have surveyed with XMM-Newton the central ~0.6{deg}^2^ region of the ELAIS-S1 field down to flux limits of ~5.5x10^-16^erg/cm^2^/s (0.5-2keV, soft band, S), ~2x10^-15^erg/cm^2^/s (2-10keV, hard band, H), and ~4x10^-15^erg/cm^2^/s (5-10keV, ultra hard band, HH). We present here the analysis of the XMM-Newton observations, the number counts in different energy bands and the clustering properties of the X-ray sources.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/488/417
- Title:
- XMM-Newton survey of the ELAIS-S1 field. II.
- Short Name:
- J/A+A/488/417
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the optical identifications and a multi-band catalogue of a sample of 478 X-ray sources detected in the XMM-Newton and Chandra surveys of the central 0.6deg^2^ of the ELAIS-S1 field. The most likely optical/infrared counterpart of each X-ray source was identified using the chance coincidence probability in the R and IRAC 3.6 micron bands.This method was complemented by the precise positions obtained through Chandra observations. We were able to associate a counterpart to each X-ray source in the catalogue. Approximately 94% of them are detected in the R band, while the remaining are blank fields in the optical down to R~24.5, but have a near-infrared counterpart detected by IRAC within 6 arcsec from the XMM-Newton centroid. The multi-band catalogue, produced using the positions of the identified optical counterparts, contains photometry in ten photometric bands, from B to the MIPS 24 micron band. The spectroscopic follow-up allowed us to determine the redshift and classification for 237 sources (~50% of the sample) brighter than R=24. The spectroscopic redshifts were complemented by reliable photometric redshifts for 68 sources. We classified 47% of the sources with spectroscopic redshift as broad-line active galactic nuclei (BL AGNs) with z=0.1-3.5, while sources without broad-lines (NOT BL AGNs) are about 46% of the spectroscopic sample and are found up to z=2.6. The remaining fraction is represented by extended X-ray sources and stars. We spectroscopically identified 11 type 2 QSOs among the sources with X/O>8, with redshift between 0.9 and 2.6, high 2-10keV luminosity (logLx>=43.8erg/s) and hard X-ray colors suggesting large absorbing columns at the rest frame (logN_H_ up to 23.6cm^-2^). BL AGNs show on average blue optical-to-near-infrared colors, softer X-ray colors and X-ray-to-optical colors typical of optically selected AGNs. Conversely, narrow-line sources show redder optical colors, harder X-ray flux ratio and span a wider range of X-ray-to-optical colors. On average the Spectral Energy Distributions (SEDs) of high-luminosity BL AGNs resemble the power-law typical of unobscured AGNs. The SEDs of NOT BLAGNs are dominated by the galaxy emission in the optical/near-infrared, and show a rise in the mid-infrared which suggests the presence of an obscured active nucleus. We study the infrared-to-optical colors and near-infrared SEDs to infer the properties of the AGN host galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/459/199
- Title:
- XMM-Newton survey of two Upper Scorpius regions
- Short Name:
- J/A+A/459/199
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We studied X-ray emission from young stars by analyzing the deep XMM-Newton observations of two regions of the Upper Scorpius association with an age of 5Myr. Based on near infrared and optical photometry we identified 22 Upper Scorpius photometric members among the 224 detected X-ray sources. We derived coronal properties of Upper Scorpius stars by performing X-ray spectral and timing analyses. The study of four strong and isolated stellar flares allowed us to derive the length of the flaring loops.
- ID:
- ivo://CDS.VizieR/J/A+A/557/A123
- Title:
- XMM-Newton Wide Angle Survey (XWAS)
- Short Name:
- J/A+A/557/A123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the XMM-Newton Wide Angle Survey (XWAS), a new catalogue of almost a thousand X-ray sources spectroscopically identified through optical observations. Sources lie in high-galactic latitude (|b|>20deg) XMM-Newton fields mainly in the southern hemisphere. A sample of X-ray sources detected in 68 XMM-Newton pointed observations was selected for optical multi-fibre spectroscopy. Optical counterparts and corresponding photometry of the X-ray sources were obtained from the SuperCOSMOS Sky Survey. Candidates for spectroscopy were initially selected with magnitudes down to R~21, with preference for X-ray sources having a flux F_0.5-4.5keV_>=10^-14^erg/s/cm2. Optical spectroscopic observations were made using the Two Degree Field of the Anglo Australian Telescope, and the resulting spectra were classified based on optical emission lines. We have identified through optical spectroscopy 940 X-ray sources over {Omega}~11.8deg^2^ of the sky. Source populations in our sample can be summarised as 65% broad line active galactic nuclei (BLAGN), 16% narrow emission line galaxies (NELGs), 6% absorption line galaxies (ALGs) and 13% stars. An active nucleus is also likely to be present in the large majority of the X-ray sources spectroscopically classified as NELGs or ALGs.
- ID:
- ivo://CDS.VizieR/J/A+A/497/635
- Title:
- XMM-Newton wide-field survey in COSMOS field
- Short Name:
- J/A+A/497/635
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The COSMOS survey is a multiwavelength survey aimed to study the evolution of galaxies, AGN and large scale structures. Within this survey XMM-COSMOS a powerful tool to detect AGN and galaxy clusters. The XMM-COSMOS is a deep X-ray survey over the full 2deg^2^ of the COSMOS area. It consists of 55 XMM-Newton pointings for a total exposure of ~1.5Ms with an average vignetting-corrected depth of 40ks across the field of view and a sky coverage of 2.13deg^2^. The analysis was performed using the XMM-SAS data analysis package in the 0.5-2keV, 2-10keV and 5-10keV energy bands. Source detection has been performed using a maximum likelihood technique especially designed for raster scan surveys. The completeness of the catalogue as well as logN-logS and source density maps have been calibrated using Monte Carlo simulations.
- ID:
- ivo://CDS.VizieR/J/ApJ/738/129
- Title:
- XMM-Newton X-ray sources in NGC 6553
- Short Name:
- J/ApJ/738/129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper reports the search for quiescent low-mass X-ray binaries (qLMXBs) in the globular cluster (GC) NGC 6553 using an XMM-Newton observation designed specifically for that purpose. We spectrally identify one candidate qLMXB in the core of the cluster, based on the consistency of the spectrum with a neutron star H-atmosphere model at the distance of NGC 6553. Specifically, the best-fit radius found using the three XMM European Photon Imaging Camera spectra is R_NS_=6.3^+2.3^_-0.8_ km (for M_NS_=1.4 M_{sun}_) and the best-fit temperature is kT_eff_=136^+21^_-34_ eV. Both physical parameters are in accordance with typical values of previously identified qLMXBs in GC and in the field, i.e., R_NS_~5-20 km and kT_eff_=50-150 eV. A power-law (PL) component with a photon index {Gamma}=2.1^+0.5^_-0.8_ is also required for the spectral fit and contributes ~33% of the total flux of the X-ray source. A detailed analysis supports the hypothesis that the PL component originates from nearby sources in the core, unresolved with XMM. The analysis of an archived Chandra observation provides marginal additional support to the stated hypothesis. Finally, a catalog of all the sources detected within the XMM field of view is presented here.
- ID:
- ivo://CDS.VizieR/J/A+A/620/A28
- Title:
- XMM northern disc of M31 sources
- Short Name:
- J/A+A/620/A28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We carried out new observations of two fields in the star-forming northern ring of M31 with XMM-Newton with two exposures of about 100 ks each. A previous XMM-Newton survey of the entire M31 galaxy revealed extended diffuse X-ray emission in these regions. We study the population of X-ray sources in the northern disc of M31 by compiling a complete list of X-ray sources down to a sensitivity limit of ~7x10^34^erg/s (0.5-2.0keV) and improve the identification of the X-ray sources. The major objective of the observing programme was the study of the hot phase of the interstellar medium (ISM) in M31. The analysis of the diffuse emission and the study of the ISM is presented in a separate paper. We analysed the spectral properties of all detected sources using hardness ratios and spectra if the statistics were high enough. We also checked for variability. In order to classify the sources detected in the new deep XMM-Newton observations, we cross-correlated the source list with the source catalogue of a new survey of the northern disc of M31 carried out with the Chandra X-ray Observatory and the Hubble Space Telescope (Panchromatic Hubble Andromeda Treasury, PHAT) as well as with other existing catalogues We detected a total of 389 sources in the two fields of the northern disc ofM31 observed with XMM-Newton.We identified 43 foreground stars and candidates and 50 background sources. Based on the comparison to the results of the Chandra/PHAT survey, we classify 24 hard X-ray sources as new candidates for X-ray binaries (XRBs). In total, we identified 34 X-ray binaries and candidates and 18 supernova remnants (SNRs) and candidates. We studied the spectral properties of the four brightest SNRs and confirmed five new X-ray SNRs. Three of the four SNRs, for which a spectral analysis was performed, show emission mainly below 2 keV, which is consistent with shocked ISM. The spectra of two of them also require an additional component with a higher temperature. The SNR [SPH11] 1535 has a harder spectrum and might suggest that there is a pulsar-wind nebula inside the SNR. For all SNRs in the observed fields, we measured the X-ray flux or calculated upper limits. We also carried out short-term and long-term variability studies of the X-ray sources and found five new sources showing clear variability. In addition, we studied the spectral properties of the transient source SWIFT J004420.1+413702, which shows significant variation in flux over a period of seven months (June 2015 to January 2016) and associated change in absorption. Based on the likely optical counterpart detected in the Chandra/PHAT survey, the source is classified as a low-mass X-ray binary.
- ID:
- ivo://CDS.VizieR/J/A+A/395/499
- Title:
- XMM observations in M8 and NGC6530
- Short Name:
- J/A+A/395/499
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of an XMM-Newton observation of the Lagoon Nebula (M 8). Our EPIC images of this region reveal a cluster of point sources, most of which have optical counterparts inside the very young open cluster NGC 6530. The bulk of these X-ray sources are probably associated with low and intermediate mass pre-main sequence stars.
- ID:
- ivo://CDS.VizieR/J/AJ/145/143
- Title:
- XMM observations of {alpha} Per
- Short Name:
- J/AJ/145/143
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the analysis of an archival observation of part of the {alpha} Persei cluster obtained with XMM-Newton. We detected 102 X-ray sources in the band 0.3-8.0 keV, of which 39 of them are associated with the cluster as evidenced by appropriate magnitudes and colors from Two Micron All Sky Survey photometry. We extend the X-ray luminosity distribution (XLD) for M dwarfs, to add to the XLD found for hotter dwarfs from spatially extensive surveys of the whole cluster by ROSAT. Some of the hotter stars are identified as a background, possible slightly older group of stars at a distance of approximately 500 pc.
- ID:
- ivo://CDS.VizieR/J/A+A/461/669
- Title:
- XMM observations of Cha I dark cloud
- Short Name:
- J/A+A/461/669
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Low-mass stars are known to exhibit strong X-ray emission during the early stages of evolution. Nearby star forming regions are ideal targets to study the X-ray properties of pre-main sequence stars. Aims. A deep XMM-Newton exposure is used to investigate X-ray properties of the pre-main sequence population of the Chamaeleon I star forming region. The northern-eastern fringe of the Chameleon I dark cloud was observed with XMM-Newton, revisiting a region observed with ROSAT 15 years ago. Centered on the extended X-ray source CHXR 49 we are able to resolve it into three major contributing components and to analyse their spectral properties. Furthermore, the deep exposure allows not only the detection of numerous, previously unknown X-ray sources, but also the investigation of variability and the study of the X-ray properties for the brighter targets in the field. We use EPIC spectra, to determine X-ray brightness, coronal temperatures and emission measures for these sources, compare the properties of classical and weak-line T Tauri stars and make a comparison with results from the ROSAT observation.
