- ID:
- ivo://CDS.VizieR/J/A+A/359/113
- Title:
- X-ray and IR study of Rho Oph dark cloud
- Short Name:
- J/A+A/359/113
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained two deep exposures of the {rho} Oph cloud core region with the ROSAT High Resolution Imager. The improved position accuracy (1"-6") with respect to previous recent X-ray observations (ROSAT PSPC, and ASCA) allows us to remove positional ambiguities for the detected sources. We also cross-correlate the X-ray positions with IR sources found in the ISOCAM survey of the same region at 6.7 and 14.3{mu}m, in addition to sources (optical and IR) known from ground-based observations, which are young stars (T Tauri stars, with and without circumstellar disks, and protostars). We thus obtain the best-studied sample of X-ray emitting stars in a star-forming region (63 X-ray sources detected, and 55 identified).
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/429/775
- Title:
- X-ray and mid-IR study of NGC 2023
- Short Name:
- J/MNRAS/429/775
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results obtained in the X-ray and infrared study in the star-forming region NGC2023. The X-ray observation (ID=0112640201) was performed as a single 30ks exposure on 2002. Afer our processing, the useful exposure time was reduced around to 15ks. Spitzer photometry (AORKEY 8773120 and 8773632) we used MOPEX to create the mosaic image and DAOPHOT package to derived the fluxes. Optical photometry (V and I magnitude) was obtained from DENIS and Mid-Infrared from 2MASS and WISE. We used Robitaille et al. (2007ApJS..169..328R) to SED fitting and derived stellar parameters.
- ID:
- ivo://CDS.VizieR/J/ApJ/747/10
- Title:
- X-ray and multiwavelength properties of 11 WLQs
- Short Name:
- J/ApJ/747/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the X-ray and multiwavelength properties of 11 radio-quiet quasars with weak or no emission lines identified by the Sloan Digital Sky Survey (SDSS) with redshift z=0.4-2.5. Our sample was selected from the Plotkin et al. catalog (2010, Cat. J/AJ/139/390) of radio-quiet, weak-featured active galactic nuclei (AGNs). The distribution of relative X-ray brightness for our low-redshift weak-line quasar (WLQ) candidates is significantly different from that of typical radio-quiet quasars, having an excess of X-ray weak sources, but it is consistent with that of high-redshift WLQs. Over half of the low-redshift WLQ candidates are X-ray weak by a factor of >~5, compared to a typical SDSS quasar with similar UV/optical luminosity. These X-ray weak sources generally show similar UV emission-line properties to those of the X-ray weak quasar PHL 1811 (weak and blueshifted high-ionization lines, weak semiforbidden lines, and strong UV Fe emission); they may belong to the notable class of PHL 1811 analogs. The average X-ray spectrum of these sources is somewhat harder than that of typical radio-quiet quasars.
- ID:
- ivo://CDS.VizieR/J/AJ/130/2212
- Title:
- X-ray and NIR studies of L1448
- Short Name:
- J/AJ/130/2212
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of X-ray and near-infrared (NIR) observations of L1448, a star-forming region in the Perseus cloud complex using the Chandra X-Ray Observatory and the 4m telescope at the Kitt Peak National Observatory. We detect 72 X-ray sources in a ~17'x17' region with a 68 ks ACIS exposure down to the X-ray flux limit of ~10^-15^ergs/s/cm2 (0.5-8keV), for which we conduct follow-up NIR imaging observations in a concentric ~11'x11' region with FLAMINGOS down to mi_Ks_~17mag. Twelve X-ray sources have NIR or optical counterparts.
- ID:
- ivo://CDS.VizieR/J/A+A/545/A66
- Title:
- X-ray and radio emission of type 1 AGNs
- Short Name:
- J/A+A/545/A66
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- X-ray emission from Active Galactic Nuclei (AGN) is dominated by the accretion disk around a supermassive black hole. The radio luminosity, however, has not such a clear origin except in the most powerful sources where jets are evident. The origin (and even the very existence) of the local bi-modal distribution in radio-loudness is also a debated issue. By analysing X-ray, optical and radio properties of a large sample of type 1 AGN and quasars (QSOs) up to z>2, where the bulk of this population resides, we aim to explore the interplay between radio and X-ray emission in AGN, in order to further our knowledge on the origin of radio emission, and its relation to accretion. We analyse a large (~800 sources) sample of type 1 AGN and QSOs selected from the 2XMMi XMM-Newton X-ray source catalogue, cross-correlated with the SDSS DR7 spectroscopic catalogue, covering a redshift range from z~0.3 to z~2.3. Supermassive black hole masses are estimated from the Mg II emission line, bolometric luminosities from the X-ray data, and radio emission or upper limits from the FIRST catalogue. Most of the sources accrete close to the Eddington limit and the distribution in radio-loudness does not appear to have a bi-modal behaviour. We confirm that radio-loud AGN are also X-ray loud, with an X-ray-to-optical ratio up to twice that of radio-quiet objects, even excluding the most extreme strongly jetted sources. By analysing complementary radio-selected control samples, we find evidence that these conclusions are not an effect of the X-ray selection, but are likely a property of the dominant QSO population. Our findings are best interpreted in a context where radio emission in AGN, with the exception of a minority of beamed sources, arises from very close to the accretion disk and is therefore heavily linked to X-ray emission. We also speculate that the radio-loud/radio-quiet dichotomy might either be an evolutionary effect that developed well after the QSO peak epoch, or an effect of incompleteness in small samples.
- ID:
- ivo://CDS.VizieR/J/A+A/568/A107
- Title:
- X-ray and radio images of SNR G351.0-5.4
- Short Name:
- J/A+A/568/A107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- While searching the NRAO VLA Sky Survey (NVSS) for diffuse radio emission, we have serendipitously discovered extended radio emission close to the Galactic plane. The radio morphology suggests the presence of a previously unknown Galactic supernova remnant. An unclassified gamma-ray source detected by EGRET (3EG J1744-3934) is present in the same location and may stem from the interaction between high-speed particles escaping the remnant and the surrounding interstellar medium. Our aim is to confirm the presence of a previously unknown supernova remnant and to determine a possible association with the gamma-ray emission 3EG J1744-3934. We have conducted optical and radio follow-ups of the target using the Dark Energy Camera (DECam) on the Blanco telescope at Cerro Tololo Inter-American Observatory (CTIO) and the Giant Meterwave Radio Telescope (GMRT). We then combined these data with archival radio and gamma-ray observations.
- ID:
- ivo://CDS.VizieR/J/BaltA/24/395
- Title:
- X-ray and radio sources in binaries
- Short Name:
- J/BaltA/24/395
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The goal of the present study was to compile complete list of binaries discovered at non-optical bands: X-ray binaries (XRB) and radio pulsars in binaries. Due to the lack of a unified identification system for XRB we had to select them from five principal catalogues of X-ray sources. After cross-identification and positional cross-matching, a general catalogue of 373 XRB was constructed for the first time. It contains coordinates, indication of photometric and spectroscopic binarity and extensive cross-identification. In the preparation of the catalogue, a number of XRB classification collisions were resolved, some catalogued identifiers and coordinates were corrected, and duplicated entries in the original catalogues were found.
- ID:
- ivo://CDS.VizieR/J/ApJ/613/393
- Title:
- X-ray and radio sources in {rho} Oph Core A
- Short Name:
- J/ApJ/613/393
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A 96ks Chandra X-ray observation of {rho} Ophiuchus cloud core A detected 87 sources, of which 60 were identified with counterparts at other wavelengths. Simultaneous multifrequency Very Large Array (VLA) observations detected 31 radio sources at 6cm, of which 10 were also detected by Chandra. We report new radio detections of the optically invisible IR source WLY 2-11 and the faint H{alpha} emission line star Elias 24 (class II).
- ID:
- ivo://CDS.VizieR/J/ApJ/657/116
- Title:
- X-ray and UV parameters of radio-quiet quasars
- Short Name:
- J/ApJ/657/116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report new Chandra observations of seven optically faint, z~4 radio-quiet quasars (RQQs). We have combined these new observations with previous Chandra observations of RQQs to create a sample of 174 sources. These sources have 0.1<z<4.7, and 10^44^ergs/s<{nu}L_{nu}_(2500{AA})<10^48^ergs/s. The X-ray detection fraction is 90%.
23770. X-Ray Binaries Catalog
- ID:
- ivo://nasa.heasarc/xrbcat
- Title:
- X-Ray Binaries Catalog
- Short Name:
- XRBs
- Date:
- 14 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- XRBCAT is a catalog of X-ray binaries, based on the van Paradijs (1996) compilation, and updated by Nick White to include all the new (mostly transient) systems discovered since then up until the last update (see below). The information in XRBCAT is basic and does not attempt to be complete. It includes the name of the source, the position, the pulse or orbital period (if one is known), the object class, a flux (a maximum and, if available, a minimum), and an optical V magnitude (if available). To reference XRBCAT, please use the following acknowledgment: "This paper utilized the HEASARC XRBCAT X-ray Binary catalog". Since it is a very time consuming task to keep track of all the new sources and discoveries, there may be incomplete or missing sources. This catalog was last updated on April 22, 1998. This is a service provided by NASA HEASARC .
