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Publisher: Les Ulis : EDP Sciences × Subject: surveys ×

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Now showing 1 - 3 of 3
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    The XMM-Newton serendipitous survey : IX. The fourth XMM-Newton serendipitous source catalogue
    (Les Ulis : EDP Sciences, 2020) Webb, N.A.; Coriat, M.; Traulsen, I.; Ballet, J.; Motch, C.; Carrera, F.J.; Koliopanos, F.; Authier, J.; de la Calle, I.; Ceballos, M.T.; Colomo, E.; Chuard, D.; Freyberg, M.; Garcia, T.; Kolehmainen, M.; Lamer, G.; Lin, D.; Maggi, P.; Michel, L.; Page, C.G.; Page, M.J.; Perea-Calderon, J.V.; Pineau, F.-X.; Rodriguez, P.; Rosen, S.R.; Santos Lleo, M.; Saxton, R.D.; Schwope, A.; Tomás, L.; Watson, M.G.; Zakardjian, A.
    Context. Sky surveys produce enormous quantities of data on extensive regions of the sky. The easiest way to access this information is through catalogues of standardised data products. XMM-Newton has been surveying the sky in the X-ray, ultra-violet, and optical bands for 20 years. Aims. The XMM-Newton Survey Science Centre has been producing standardised data products and catalogues to facilitate access to the serendipitous X-ray sky. Methods. Using improved calibration and enhanced software, we re-reduced all of the 14 041 XMM-Newton X-ray observations, of which 11 204 observations contained data with at least one detection and with these we created a new, high quality version of the XMM-Newton serendipitous source catalogue, 4XMM-DR9. Results. 4XMM-DR9 contains 810 795 detections down to a detection significance of 3σ, of which 550 124 are unique sources, which cover 1152 degrees2 (2.85%) of the sky. Filtering 4XMM-DR9 to retain only the cleanest sources with at least a 5σ detection significance leaves 433 612 detections. Of these detections, 99.6% have no pileup. Furthermore, 336 columns of information on each detection are provided, along with images. The quality of the source detection is shown to have improved significantly with respect to previous versions of the catalogues. Spectra and lightcurves are also made available for more than 288 000 of the brightest sources (36% of all detections).
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    The final SDSS-IV/SPIDERS X-ray point source spectroscopic catalogue
    (Les Ulis : EDP Sciences, 2020) Comparat, J.; Merloni, A.; Dwelly, T.; Salvato, M.; Schwope, A.; Coffey, D.; Wolf, J.; Arcodia, R.; Liu, T.; Buchner, J.; Nandra, K.; Georgakakis, A.; Clerc, N.; Brusa, M.; Brownstein, J.R.; Schneider, D.P.; Pan, K.; Bizyaev, D.
    Aims. We look to provide a detailed description of the SPectroscopic IDentification of ERosita Sources (SPIDERS) survey, an SDSS-IV programme aimed at obtaining spectroscopic classification and redshift measurements for complete samples of sufficiently bright X-ray sources. Methods. We describe the SPIDERS X-ray Point Source Spectroscopic Catalogue, considering its store of 11 092 observed spectra drawn from a parent sample of 14 759 ROSAT and XMM sources over an area of 5129 deg2 covered in SDSS-IV by the eBOSS survey. Results. This programme represents the largest systematic spectroscopic observation of an X-ray selected sample. A total of 10 970 (98.9%) of the observed objects are classified and 10 849 (97.8%) have secure redshifts. The majority of the spectra (10 070 objects) are active galactic nuclei (AGN), 522 are cluster galaxies, and 294 are stars. Conclusions. The observed AGN redshift distribution is in good agreement with simulations based on empirical models for AGN activation and duty cycle. Forming composite spectra of type 1 AGN as a function of the mass and accretion rate of their black holes reveals systematic differences in the H-beta emission line profiles. This study paves the way for systematic spectroscopic observations of sources that are potentially to be discovered in the upcoming eROSITA survey over a large section of the sky.
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    The eROSITA extragalactic CalPV serendipitous catalog
    (Les Ulis : EDP Sciences, 2022) Liu, Teng; Merloni, Andrea; Wolf, Julien; Salvato, Mara; Reiprich, Thomas H.; Comparat, Johan; Arcodia, Riccardo; Lamer, Georg; Georgakakis, Antonis; Dwelly, Tom; Sanders, Jeremy; Buchner, Johannes; Haberl, Frank; Ramos-Ceja, Miriam E.; Wilms, Jörn; Nandra, Kirpal; Brunner, Hermann; Brusa, Marcella; Schwope, Axel; Robrade, Jan; Freyberg, Michael; Boller, Thomas; Maitra, Chandreyee; Veronica, Angie; Malyali, Adam
    Context. The eROSITA X-ray telescope on board the Spectrum-Roentgen-Gamma (SRG) observatory performed calibration and performance verification (CalPV) observations between September 2019 and December 2019, ahead of the planned 4-yr all-sky surveys. Most of them were deep, pointing-mode observations. Aims. We present here the X-ray catalog detected from the set of extra-galactic CalPV observations released to the public by the German eROSITA consortium, and the multiband counterparts of these X-ray sources. Methods. We developed a source detection method optimized for point-like X-ray sources by including extended X-ray emission in the background measurement. The multiband counterparts were identified using a Bayesian method from the CatWISE catalog. Results. Combining 11 CalPV fields, we present a catalog containing 9515 X-ray sources, whose X-ray fluxes were measured through spectral fitting. CatWISE counterparts are presented for 77% of the sources. Significant variabilities are found in 99 of the sources, which are also presented with this paper. Most of these fields show similar number counts of point sources as typical extragalactic fields, and a few harbor particular stellar populations.