- ID:
- ivo://CDS.VizieR/J/ApJ/716/474
- Title:
- The Rosette star-forming complex. III.
- Short Name:
- J/ApJ/716/474
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present high spatial resolution Chandra X-ray images of the NGC 2237 young stellar cluster on the periphery of the Rosette Nebula. We detect 168 X-ray sources, 80% of which have stellar counterparts in USNO, Two Micron All Sky Survey, and deep FLAMINGOS images. These constitute the first census of the cluster members with 0.2<~M<~2M_{sun}_. Star locations in near-infrared color-magnitude diagrams indicate a cluster age around 2Myr with a visual extinction of 1<~A_V_<~3 at 1.4kpc, the distance of the Rosette Nebula's main cluster NGC 2244. We derive the K-band luminosity function and the X-ray luminosity function of the cluster, which indicate a population ~400-600 stars. The X-ray-selected sample shows a K-excess disk frequency of 13%. The young Class II counterparts are aligned in an arc ~3pc long suggestive of a triggered formation process induced by the O stars in NGC 2244. The diskless Class III sources are more dispersed. Several X-ray emitting stars are located inside the molecular cloud and around gaseous pillars projecting from the cloud. This X-ray view of young stars on the western side of the Rosette Nebula complements our earlier studies of the central cluster NGC 2244 and the embedded clusters on the eastern side of the Nebula. The large-scale distribution of the clusters and molecular material is consistent with a scenario in which the rich central NGC 2244 cluster formed first, and its expanding HII region triggered the formation of the now-unobscured satellite clusters Rosette Molecular Cloud (RMC) XA and NGC 2237. A large swept-up shell material around the HII region is now in a second phase of collect-and-collapse fragmentation, leading to the recent formation of subclusters.
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- ID:
- ivo://CDS.VizieR/J/ApJS/183/17
- Title:
- The SDSS DR5/XMM-Newton quasar survey
- Short Name:
- J/ApJS/183/17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 792 Fifth Data Release Sloan Digital Sky Survey quasars with optical spectra that have been observed serendipitously in the X-rays with the XMM-Newton. These quasars cover a redshift range of z=0.11-5.41 and a magnitude range of i=15.3-20.7. Substantial numbers of radio-loud (70) and broad absorption line (51) quasars exist within this sample. Significant X-ray detections at >=2{sigma} account for 87% of the sample (685 quasars), and 473 quasars are detected at >=6{sigma}, sufficient to allow X-ray spectral fits. For detected sources, ~60% have X-ray fluxes between F_2-10keV_=(1-10)x10^-14^erg/cm^2^/s. We fit a single power law, a fixed power law with intrinsic absorption left free to vary, and an absorbed power-law model to all quasars with X-ray signal-to-noise ratio >=6, resulting in a weighted mean photon index {Gamma}=1.91+/-0.08, with an intrinsic dispersion {sigma}_{Gamma}_=0.38.
- ID:
- ivo://CDS.VizieR/J/ApJS/187/64
- Title:
- The simultaneous optical-to-X-ray SED of AGNs
- Short Name:
- J/ApJS/187/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report Swift observations of a sample of 92 bright soft X-ray selected active galactic nuclei (AGNs). This sample represents the largest number of AGNs observed to study the spectral energy distribution (SED) of AGNs with simultaneous optical/UV and X-ray data. The principal motivation of this study is to understand the SEDs of AGNs in the optical/UV to X-ray regime and to provide bolometric corrections which are important in determining the Eddington ratio L/L_Edd_. In particular, we rigorously explore the dependence of the UV-EUV contribution to the bolometric correction on the assumed EUV spectral shape. We find strong correlations of the spectral slopes {alpha}_X_ and {alpha}_UV_ with L/L_Edd_.
- ID:
- ivo://CDS.VizieR/J/MNRAS/341/1093
- Title:
- The Southern SHARC catalogue
- Short Name:
- J/MNRAS/341/1093
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Southern Serendipitous High-redshift Archival Cluster (SHARC) catalogue is a X-ray selected catalogue of galaxy clusters detected in deep ROSAT observations. The survey area is 17.7deg^2^ and is selected from long (greater than 10ks) ROSAT exposures with a declination <+20deg and excluding the Galactic plane (excluding galactic latitudes within the range [-20,20]deg). Optical follow-up was performed to confirm the presence of a galaxy cluster and measure its redshift. The final catalogue contains 32 galaxy clusters with redshifts between 0.05 and 0.70 and X-ray luminosities between 7x10^35^W and 4x10^37^W. Above a redshift of 0.3 - which forms the primary subsample of the survey - there are 16 clusters; the X-ray luminosities of these clusters are all greater than 2x10^36 W. All X-ray luminosities are quoted in the 0.5-2.0keV band and were calculated using an Einstein-de Sitter cosmology with H_0_ set to 50km/s/Mpc.
- ID:
- ivo://CDS.VizieR/J/ApJ/868/47
- Title:
- The 1st year of the Swift SMC Survey (S-CUBED)
- Short Name:
- J/ApJ/868/47
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Swift Small Magellanic Cloud (SMC) Survey, S-CUBED, is a high-cadence shallow X-ray survey of the SMC. The survey consists of 142 tiled pointings covering the optical extent of the SMC, which is performed weekly by NASA's Neil Gehrels Swift Observatory, with an exposure per tile of 60s. The survey is focused on discovery and monitoring of X-ray outbursts from the large known and unknown population of Be/X-ray binaries (BeXRBs) in the SMC. Given the very low background of Swift's X-ray telescope, even with a short exposure per tile, S-CUBED is typically sensitive to outbursts in the SMC at >1%-2% Eddington luminosity for a typical 1.4M_{sun}_ neutron star compact object. This sensitivity, combined with the high cadence and the fact that the survey can be performed all year round, makes it a powerful discovery tool for outbursting accreting X-ray pulsars in the SMC. In this paper we describe results from the first year of observations of S-CUBED, which includes the 1SCUBEDX catalog of 265 X-ray sources, 160 of which are not identified with any previously cataloged X-ray source. We report on bulk properties of sources in the 1SCUBEDX catalog. Finally, we focus on results of S-CUBED observations of several interesting sources, which includes discovery of three Type II outbursts from BeXRBs and the detection of Type I outbursts and orbital periods in six BeXRB systems.
- ID:
- ivo://CDS.VizieR/J/ApJS/209/14
- Title:
- The Swift/BAT hard X-ray transient monitor
- Short Name:
- J/ApJS/209/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Swift/Burst Alert Telescope (BAT) hard X-ray transient monitor provides near real-time coverage of the X-ray sky in the energy range 15-50 keV. The BAT observes 88% of the sky each day with a detection sensitivity of 5.3 mCrab for a full-day observation and a time resolution as fine as 64s. The three main purposes of the monitor are (1) the discovery of new transient X-ray sources, (2) the detection of outbursts or other changes in the flux of known X-ray sources, and (3) the generation of light curves of more than 900 sources spanning over eight years. The primary interface for the BAT transient monitor is a public Web site. Between 2005 February 12 and 2013 April 30, 245 sources have been detected in the monitor, 146 of them persistent and 99 detected only in outburst. Among these sources, 17 were previously unknown and were discovered in the transient monitor. In this paper, we discuss the methodology and the data processing and filtering for the BAT transient monitor and review its sensitivity and exposure. We provide a summary of the source detections and classify them according to the variability of their light curves. Finally, we review all new BAT monitor discoveries. For the new sources that are previously unpublished, we present basic data analysis and interpretations.
- ID:
- ivo://CDS.VizieR/IX/12
- Title:
- The WGACAT version of ROSAT sources
- Short Name:
- IX/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- WGACAT is a catalogue of point sources generated at HEASARC from all the ROSAT PSPC (Position Sensitive Proportional Counter) pointing observations from Feb 1991 to March 1994. These were the files available in the public archive at HEASARC as of September 1994. This catalog is an independent research effort aimed at releasing as quickly as possible a list of sources detected by ROSAT in its pointed phase to: (1) identify the detected sources, (2) ensure their timely observation by currently active X-ray missions e.g. ASCA, (3) to search for objects which show exceptional time variability and spectral properties and (4) to provide an independent check of the detection technique used in the official ROSAT project (SAS) processing. WGACAT stands for N.E. White (HEASARC/GSFC). P. Giommi (ESA), and L. Angelini (HEASARC/GSFC)
- ID:
- ivo://CDS.VizieR/IX/31
- Title:
- The WGACAT version of ROSAT sources
- Short Name:
- IX/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- WGACAT is a point source catalogue generated from all ROSAT PSPC (Position Sensitive Proportional Counter) pointed observations. This catalog has been generated by N.E. White (HEASARC/GSFC), P. Giommi (SDC/ASI) and L. Angelini (HEASARC/GSFC) and is a private research effort, not related to the official catalogs generated by the ROSAT project. The WGACAT was made first publicly available in November 1994 through the HEASARC on-line service (White, Giommi and Angelini 1994), with a first minor revision in March 1995 (WGACAT95). It was generated using all the public ROSAT PSPC pointed data available than, corresponding to 75% of the entire set, and featured ~ 68000 detections of which 62000 were unique sources. The current version, released in May 2000, is the final and complete version of WGACAT and includes the remaining sequences not processed in the WGACAT95. WGACAT (May 2000) contains about 88,000 detections, with more than 84,000 individual sources, obtained from 4160 sequences. The catalog was generated using an optimized sliding cell detect algorithm in XIMAGE (first developed for the EXOSAT project). The inner and outer parts of the images were run separately, to maximize the sensitivity to source detection. This method is very sensitive in finding point sources, but can also find spurious sources where there is extended emission. We have visually inspected each detection, removed the obvious spurious cases and assigned a quality flag to each detection.
- ID:
- ivo://CDS.VizieR/J/A+A/577/A121
- Title:
- The XMM-ATLAS catalogues
- Short Name:
- J/A+A/577/A121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Wide area X-ray and far infrared surveys are a fundamental tool to investigate the link between AGN growth and star formation, especially in the low-redshift universe (z<1). The Herschel Terahertz Large Area survey (H-ATLAS) has covered 550deg^2^ in five far-infrared and sub-mm bands, 16deg^2^ of which have been presented in the Science Demonstration Phase (SDP) catalogue. Here we introduce the XMM-Newton observations in H-ATLAS SDP area, covering 7.1deg^2^ with flux limits of 2*10^-15^, 6*10^-15^, and 9*10^-15^erg/s/cm^2^ in the 0.5-2, 0.5-8 and 2-8keV bands, respectively. We present the source detection and the catalogue, which includes 1700, 1582 and 814 sources detected by emldetect in the 0.5-8, 0.5-2 and 2-8keV bands, respectively; the number of unique sources is 1816. We extract spectra and derive fluxes from power-law fits for 398 sources with more than 40 counts in the 0.5-8keV band. We compare the best-fit fluxes with the catalogue ones, obtained by assuming a common photon index of Gamma=1.7; we find no bulk difference between the fluxes, and a moderate dispersion of s=0.33dex. Using wherever possible the fluxes from the spectral fits, we derive the 2-10keV Log N-Log S, which is consistent with a Euclidean distribution. Finally, we release computer code for the tools developed for this project.
- ID:
- ivo://CDS.VizieR/J/A+A/555/A42
- Title:
- The XMM-CDFS catalogues
- Short Name:
- J/A+A/555/A42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Nuclear obscuration plays a key role in the initial phases of AGN growth, yet not many highly obscured AGN are currently known beyond the local Universe, and their search is an active topic of research. The XMM-Newton survey in the Chandra Deep Field South (XMM-CDFS) aims at detecting and studying the spectral properties of a significant number of obscured and Compton-thick (NH=10^24^cm^-2^ ) AGN. The large effective area of XMM-Newton in the 2-10 and 5-10keV bands, coupled with a 3.45Ms nominal exposure time (2.82 and 2.45Ms after lightcurve cleaning for MOS and PN respectively), allows us to build clean samples in both bands, and makes the XMM-CDFS the deepest XMM-Newton survey currently published in the 5-10keV band. The large multi- wavelength and spectroscopic coverage of the CDFS area allows for an immediate and abundant scientific return. In this paper, we present the data reduction of the XMM-CDFS observations, the method for source detection in the 2-10 and 5-10keV bands, and the resulting catalogues. A number of 339 and 137 sources are listed in the above bands with flux limits of 6.6x10^-16^ and 9.5x10^-16^erg/s/cm^2^, respectively. The flux limits at 50% of the maximum sky coverage are 1.8x10^-15^ and 4.0x10^-15^erg/s/cm^2^, respectively. The catalogues have been cross-correlated with the Chandra ones: 315 and 130 identifications have been found with a likelihood- ratio method, respectively. A number of 15 new sources, previously undetected by Chandra, is found; 5 of them lie in the 4Ms area. Redshifts, either spectroscopic or photometric, are available for ~92% of the sources. The number counts in both bands are presented and compared to other works. The survey coverage has been calculated with the help of two extensive sets of simulations, one set per band. The simulations have been produced with a newly-developed simulator, written with the aim of the most careful reproduction of the background spatial properties. For this reason, we present a detailed decomposition of the XMM-Newton background into its components: cosmic, particle, and residual soft protons. The three components have different spatial distributions. The importance of these three components depends on the band and on the camera; the particle background is the most important one (80-90% of the background counts), followed by the soft protons (4-20%).
