The low-frequency radio survey of the XMM-Large Scale Structure (XMM-LSS) field aims to study the connection between the extragalactic radio source populations and their environment as traced by X-ray and optical emission. In this paper we present new radio observations of the XMM-LSS field carried out using the Giant Meterwave Radio Telescope at 240 and 610MHz. These observations complement the observations presented by Cohen at al. (2003, Cat. <J/ApJ/591/640>) and Tasse et al. (2006, Cat. <J/A+A/456/791>) at 74 and 325MHz with the Very Large Array. At 240 and 610MHz, we reach noise levels of ~2.5 and ~0.3mJy/beam, leading to the detection of 466 and 769 sources over 18.0 and 12.7 degree^2^ with resolutions of 14.7arcsec and 6.5arcsec respectively. Combining these data with the available source lists at 74, 325 (Tasse et al., 2006, Cat. <J/A+A/456/791>) and 1400MHz (NVSS), we build a multifrequency catalogue containing 1611 radio sources. We check for consistency of the astrometry and flux density estimates. We fit a simple synchrotron radiation model to the flux density measurements of the 318 radio sources being detected in at least 4 bands. While ~26% of them show signature of spectral ageing, ~6% show self absorption.
We provide the source list for the first 5.5 surveyed square degrees of the XMM-LSS, with a total of 3385 point-like or extended sources above a detection likelihood of 15 in either 0.5-2 or 2-10keV bands. The table at CDS contains the main parameters, while further parameters and data products (X-ray images and optical thumbnails) are available in the Milan XMM-LSS database site.
We present the final release of the multiwavelength XMM-Large Scale Structure (LSS) data set, covering the full survey area of 11.1deg^2^, with X-ray data processed with the latest XMM-LSS pipeline version. The present publication supersedes the catalogue from the first paper in this series, pertaining to the initial 5deg^2^. We provide X-ray source lists in the customary energy bands (0.5-2 and 2-10keV) for a total of 6721 objects in the deep full-exposure catalogue and 5572 in the catalogue limited to 10ks, above a detection likelihood of 15 in at least one band. We also provide a multiwavelength catalogue, cross-correlating our list with infrared, near-infrared, optical and ultraviolet catalogues. Customary data products, such as X-ray fits images and thumbnail images from the Canada-France-Hawaii Telescope Legacy Survey and the Spitzer Wide-Area Infrared Extragalactic Survey, are made available, together with our data base in Milan, which can be queried interactively.
The XMM Large Scale Structure survey (XMM-LSS) is an X-ray survey aimed at studying the large scale structure of the Universe. The XMM-LSS field is currently being followed up using observations across a wide range of wavelengths, and in this paper we present the observational results of a low frequency radio survey of the XMM-LSS field using the Very Large Array at 74 and 325MHz. This survey will map out the locations of the extragalactic radio sources relative to the large scale structure as traced by the X-ray emission. This is of particular interest because radio galaxies and radio loud AGN show strong and complex interactions with their small and larger scale environment, and different classes of radio galaxies are suggested to lie at different places with respect to the large scale structure.
We present an X-ray point-source catalogue from the XMM-Large Scale Structure (XMM-LSS) survey region, one of the XMM-Spitzer Extragalactic Representative Volume Survey (XMM-SERVS) fields. We target the XMM-LSS region with 1.3Ms of new XMM-Newton AO-15 observations, transforming the archival X-ray coverage in this region into a 5.3deg^2^ contiguous field with uniform X-ray coverage totaling 2.7Ms of flare-filtered exposure, with a 46ks median PN exposure time. We provide an X-ray catalogue of 5242 sources detected in the soft (0.5-2keV), hard (2-10keV), and/or full (0.5-10keV) bands with a 1 per cent expected spurious fraction determined from simulations. A total of 2381 new X-ray sources are detected compared to previous source catalogues in the same area. Our survey has flux limits of 1.7x10^-15^, 1.3x10^-14^, and 6.5x10^-15^erg/cm^2^/s over 90 per cent of its area in the soft, hard, and full bands, respectively, which is comparable to those of the XMM-COSMOS survey. We identify multiwavelength counterpart candidates for 99.9 per cent of the X-ray sources, of which 93 per cent are considered as reliable based on their matching likelihood ratios. The reliabilities of these high-likelihood-ratio counterparts are further confirmed to be ~=97 per cent reliable based on deep Chandra coverage over ~=5 per cent of the XMM-LSS region. Results of multiwavelength identifications are also included in the source catalogue, along with basic optical-to-infrared photometry and spectroscopic redshifts from publicly available surveys. We compute photometric redshifts for X-ray sources in 4.5 deg^2^ of our field where forced-aperture multiband photometry is available; >70 per cent of the X-ray sources in this subfield have either spectroscopic or high-quality photometric redshifts.
The XMM-Large Scale Structure survey field (XMM-LSS) is an extragalactic window surveyed in the X-ray with the XMM-Newton satellite. It has also been observed in the optical with the Canada-France Hawaii Telescope (CFHTLS survey), and in the infrared with the Spitzer Space Telescope (SWIRE survey). These surveys have been carried out to study the structure and evolution of both baryonic and dark matter on cosmological scales. In two previous papers, we presented deep low frequency radio surveys of the XMM-LSS field, with limiting flux density levels of ~4 and ~1.5mJy/beam at 325 and 610MHz respectively (5{sigma}). These radio surveys were motivated by the need to understand the various connections between the host galaxies of radio sources and their environments. In this paper, we identify optical counterparts to the low frequency radio sources, using the CFHTLS optical catalogue and images, that have an i-band limiting magnitude of i_AB_~25.
The XMM-Large Scale Structure survey (XMM-LSS), covering an area of 11.1 sq. deg., contains more than 6000 X-ray point-like sources detected with XMM-Newton to a flux of 3x10^-15^erg/s/cm^2^ in the [0.5-2]keV band. The vast majority of these sources have optical (CFHTLS), infrared (SWIRE IRAC and MIPS), near-infrared (UKIDSS) and/or ultraviolet (GALEX) counterparts. We wish to investigate the environmental properties of the different types of the XMM-LSS X-ray sources by defining their environment using the i'-band CFHTLS W1 catalog of optical galaxies to a magnitude limit of 23.5mag. We have classified 4435 X-ray selected sources on the basis of their spectra, SEDs, and X-ray luminosity, and estimated their photometric redshifts, which have a 4-11 band photometry with an accuracy of sigma_dz_/(1+z_sp_)=0.076 with 22.6% outliers for i'<26mag. We estimated the local overdensities of 777 X-ray sources that have spectro-z or photo-z calculated by using more than seven bands (accuracy of sigma_dz_/(1+z_sp_)=0.061 with 13.8% outliers) within the volume-limited region defined by 0.1<z<0.85 and -23.5<M_i'_<-20. Although X-ray sources may be found in variety of environments, a high fraction (~55-60%), as verified by comparing with the random expectations, reside in overdense regions. The galaxy overdensities within which X-ray sources reside show a positive recent redshift evolution (at least for the range studied; z<0.85). We also find that X-ray selected galaxies, when compared to AGN, inhabit significantly higher galaxy overdensities, although their spatial extent appear to be smaller than that of AGN. Hard AGN (HR>-0.2) are located in more overdense regions than soft AGN (HR<-0.2), which is clearly seen in both redshift ranges, although it appears to be stronger in the higher redshift range (0.55<z<0.85). Furthermore, the galaxy overdensities (with {delta}>1.5) within which soft AGN are embedded appear to evolve more rapidly compared to the corresponding overdensities around hard AGN.
The XMM Large-Scale Structure Survey (XMM-LSS) is a major project to map the large-scale structure of the universe out to cosmological distances. An 8x8 region will be surveyed by XMM with planned optical follow-up to produce a three-dimensional map of many hundreds of clusters out to a redshift of z=1. To explore the relation of the large-scale structure to the location and properties of extragalactic radio sources, the XMM-LSS project also includes a low-frequency radio survey of this region. This combination will provide unprecedented insight into how the radio source formation and evolution are affected by the local environment. Here we present preliminary results from our 325 and 74MHz surveys in this region. At 325MHz, we have a flux limit of 4mJy/beam, a resolution of 6.3", and a total of 256 source detections over 5.6deg^2^. At 74MHz, we have a flux limit of 275mJy/beam, a resolution of 30", and a total of 211 source detections over 110deg^2^. We describe these results and explore what they tell us about the population of extragalactic low-frequency radio sources. The 74MHz survey represents the first presentation of a deep, subarcminute resolution survey at such a low frequency. This was made possible by recent advances in both hardware and data reduction algorithms, which we describe in detail.
Our goal is to characterize AGN populations by comparing their X-ray and optical classifications within the framework of the standard orientation-based unified scheme. We present a sample of 99 spectroscopically identified (R<=22mag) X-ray selected point sources in the XMM-LSS survey which are significantly detected (>=3{sigma}) in the [2-10]keV band with fluxes between 8x10^-15^ and 8x10^-14^erg/s/cm^2^, and which have more than 80 counts. We have compared their X-ray and optical classifications. To this end, we performed an X-ray spectral analysis for all of these 99 X-ray sources in order to assess whether they are intrinsically absorbed or not. The X-ray classification is based on the measured intrinsic column density. The optical classification is based on the measured FWHM of the permitted emission lines, the absence of broad lines being due to obscuration within the framework of the standard AGN unified scheme.
This database table contains the current target list of the X-ray Multi-Mirror Newton (XMM-Newton) mission including those in (i) the routine calibration plan, (ii) the Guaranteed Time Observation (GTO) program, (iii) the triggered target candidates or ToOs accepted for the First through the Twentieth-Third Announcements of Opportunity (AO-1 through AO-23) programs, (iv) the AO-1 through AO-23 Guest Observer (GO) program targets with priority A or B, (v) the AO-1 through AO-19 GO program targets with priority C which have been observed, (vi) the AO-20 through AO-23 GO program targets with priority C, and (vii) the targets granted by agreement of the ESA Director of Science and the National Space Agency of Japan, following the loss of the original Astro-E spacecraft. For complete and authoritative information on the XMM-Newton mission, policies, and data archive, refer to the web pages of the European Space Agency's (ESA's) XMM-Newton Science Operations Center at <a href="http://xmm.esac.esa.int/">http://xmm.esac.esa.int/</a> and of NASA's XMM-Newton Guest Observer Facility at <a href="http://heasarc.gsfc.nasa.gov/docs/xmm/xmmgof.html">http://heasarc.gsfc.nasa.gov/docs/xmm/xmmgof.html</a> Notice that all priority C targets from AOs 1 through 19 which were never observed by XMM-Newton (and hence have expired) have been removed from this table. To check which targets have either already been observed by XMM-Newton or are on the short-term schedule to be observed in the next few weeks, users should examine the <a href="/db-perl/W3Browse/w3table.pl?tablehead=name%3Dxmmmaster&Action=More+Options">XMMMASTER</a> table which is also contained in Browse. To find out which targets are currently scheduled to be observed in the next three months, the user should check the XMM-Newton Advanced Plan at <a href="http://xmm.esac.esa.int/external/xmm_sched/advance_plan.shtml">http://xmm.esac.esa.int/external/xmm_sched/advance_plan.shtml</a> While abstracts are available for most proposals, there are a number of targets for which the HEASARC lacks the corresponding abstracts: e.g., the abstracts for AO-2 Guest Observer targets which have non-US PIs are not available. This database table was last updated by the HEASARC in December 2023, when AO-23's accepted targets were added. <p> AO-22's accepted targets were added in November 2022. <p> AO-21's accepted targets were added and AO-19's unobserved priority C targets were removed in December 2021. <p> AO-20's accepted targets were added and AO-18's unobserved priority C targets were removed in December 2020. <p> AO-19's accepted targets were added and AO-17's unobserved priority C targets were removed in April 2020. <p> In June 2019, many duplicate entries were removed. <p> AO-18's accepted targets were added and AO-16's unobserved priority C targets were removed in November 2018. <p> AO-17's accepted targets were added and AO-15's unobserved priority C targets were removed in November 2017. <p> AO-16's accepted targets were added and AO-14's unobserved priority C targets were removed in December 2016. <p> AO-15's accepted targets were added and AO-13's unobserved priority C targets were removed in December 2015. <p> In August 2015, proposal titles were added. <p> AO-14's accepted targets were added and AO-12's unobserved priority C targets were removed in December 2014. <p> AO-13's accepted targets were added and AO-11's unobserved priority C targets were removed in December 2013. <p> AO-12's accepted targets were added and AO-10's unobserved priority C targets were removed in December 2012. <p> AO-11's accepted targets were added and AO-9's unobserved priority C targets were removed in December 2011. <p> AO-10's accepted targets were added and AO-8's unobserved priority C targets were removed in December 2010. <p> AO-9's accepted targets were added and AO-7's unobserved priority C targets were removed in January 2010. <p> AO-8's accepted targets were added and AO-6's unobserved priority C targets were removed in December 2008. <p> AO-7's accepted targets were added and AO-5's unobserved priority C targets were removed in January 2008. <p> AO-6's accepted targets were added in January 2007, and, in November 2006, an effort was made to remove most of the unobserved priority C targets from previous AOs. This is a service provided by NASA HEASARC .