- ID:
- ivo://CDS.VizieR/J/ApJS/235/43
- Title:
- The 2nd MSFRs Omnibus X-ray Catalog (MOXC2)
- Short Name:
- J/ApJS/235/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the second installment of the Massive Star-forming Regions (MSFRs) Omnibus X-ray Catalog (MOXC2), a compilation of X-ray point sources detected in Chandra/ACIS observations of 16 Galactic MSFRs and surrounding fields. MOXC2 includes 13 ACIS mosaics, three containing a pair of unrelated MSFRs at different distances, with a total catalog of 18396 point sources. The MSFRs sampled range over distances of 1.3kpc to 6kpc and populations varying from single massive protostars to the most massive Young Massive Cluster known in the Galaxy. By carefully detecting and removing X-ray point sources down to the faintest statistically significant limit, we facilitate the study of the remaining unresolved X-ray emission. Through comparison with mid-infrared images that trace photon-dominated regions and ionization fronts, we see that the unresolved X-ray emission is due primarily to hot plasmas threading these MSFRs, the result of feedback from the winds and supernovae of massive stars. The 16 MSFRs studied in MOXC2 more than double the MOXC1 sample, broadening the parameter space of ACIS MSFR explorations and expanding Chandra's substantial contribution to contemporary star formation science.
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- ID:
- ivo://CDS.VizieR/J/A+A/652/A12
- Title:
- The new X-Class catalogue
- Short Name:
- J/A+A/652/A12
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Cosmological probes based on galaxy clusters rely on cluster number counts and large-scale structure information. X-ray cluster surveys are well suited for this purpose, since they are far less affected than optical surveys by projection effects, and cluster properties can be predicted with good accuracy. The XMM Cluster Archive Super Survey, X-CLASS, is a serendipitous search of X-ray-detected galaxy clusters in 4176 XMM-Newton archival observations until August 2015. All observations are clipped to exposure times of 10 and 20 ks to obtain uniformity and they span ~269 sq. deg. across the high-Galactic latitude sky (|b|>20deg). The main goal of the survey is the compilation of a well-selected cluster sample suitable for cosmological analyses. We describe the detection algorithm, the visual inspection, the verification process and the redshift validation of the cluster sample, as well as the cluster selection function computed by simulations. We also present the various metadata that are released with the catalogue, along with the redshifts of 124 clusters obtained with a dedicated multi-object spectroscopic follow-up programme. With this publication we release the new X-CLASS catalogue of 1646 well-selected X-ray-detected clusters over a wide sky area, along with their selection function. The sample spans a wide redshift range, from the local Universe up to z~1.5, with 982 spectroscopically confirmed clusters, and over 70 clusters above z=0.8. Because of its homogeneous selection and thorough verification, the cluster sample can be used for cosmological analyses, but also as a test-bed for the upcoming eROSITA observations and other current and future large-area cluster surveys. It is the first time that such a catalogue is made available to the community via an interactive database which gives access to a wealth of supplementary information, images, and data.
- ID:
- ivo://CDS.VizieR/J/ApJS/179/1
- Title:
- The OPTX project: CLANS, CLASXS and CDF-N
- Short Name:
- J/ApJS/179/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the redshift catalogs for the X-ray sources detected in the Chandra Deep Field-North (CDF-N), the Chandra Large Area Synoptic X-ray Survey (CLASXS), and the Chandra Lockman Area North Survey (CLANS). The catalogs for the CDF-N and CLASXS fields include redshifts from previous work, while the redshifts for the CLANS field are all new. For fluxes above 10^-14^ergs/cm^2^/s (2-8keV) we have redshifts for 76% of the sources. We extend the redshift information for the full sample using photometric redshifts. The goal of the OPTX Project is to use these three surveys, which are among the most spectroscopically complete surveys to date, to analyze the effect of spectral type on the shape and evolution of the X-ray luminosity functions and to compare the optical spectral types with the X-ray spectral properties. We also present the CLANS X-ray catalog. The nine ACIS-I fields cover a solid angle of ~0.6deg^2^ and reach fluxes of 7x10^-16^ergs/cm^2^/s (0.5-2keV) and 3.5x10^-15^ergs/cm^2^/s (2-8keV). We find a total of 761 X-ray point sources. In addition, we present the optical and infrared photometric catalog for the CLANS X-ray sources, as well as updated optical and infrared photometric catalogs for the X-ray sources in the CLASXS and CDF-N fields.
- ID:
- ivo://CDS.VizieR/J/ApJ/703/2160
- Title:
- The OPTX project. III.
- Short Name:
- J/ApJ/703/2160
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We compare the optical spectral types with the X-ray spectral properties for a uniformly selected (sources with fluxes greater than the 3{sigma} level and above a flux limit of f(2-8keV)>3.5x10^-15^erg/cm^2^/s), highly spectroscopically complete (>80% for f(2-8keV)>10^-14^erg/cm^2^/s and >60% below) 2-8keV X-ray sample observed in three Chandra fields (CLANS, CLASXS, and the CDF-N) that cover ~1.2deg^2^. For our sample of 645 spectroscopically observed sources, we confirm that there is significant overlap of the X-ray spectral properties, as determined by the effective photon indices, {Gamma}_eff_, obtained from the ratios of the 0.5-2keV to 2-8keV counts, for the different optical spectral types. Thus, one cannot use the X-ray spectral classifications and the optical spectral classifications equivalently. Since it is not understood how X-ray and optical classifications relate to the obscuration of the central engine, we strongly advise against a mixed classification scheme, as it can only complicate the interpretation of X-ray AGN samples.
- ID:
- ivo://CDS.VizieR/J/ApJ/822/93
- Title:
- The population of compact radio sources in ONC
- Short Name:
- J/ApJ/822/93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a deep centimeter-wavelength catalog of the Orion Nebula Cluster (ONC), based on a 30hr single-pointing observation with the Karl G. Jansky Very Large Array in its high-resolution A-configuration using two 1GHz bands centered at 4.7 and 7.3GHz. A total of 556 compact sources were detected in a map with a nominal rms noise of 3{mu}Jy/bm, limited by complex source structure and the primary beam response. Compared to previous catalogs, our detections increase the sample of known compact radio sources in the ONC by more than a factor of seven. The new data show complex emission on a wide range of spatial scales. Following a preliminary correction for the wideband primary-beam response, we determine radio spectral indices for 170 sources whose index uncertainties are less than +/-0.5. We compare the radio to the X-ray and near-infrared point-source populations, noting similarities and differences.
- ID:
- ivo://CDS.VizieR/J/ApJS/244/28
- Title:
- The 3rd MSFRs Omnibus X-ray Catalog (MOXC3)
- Short Name:
- J/ApJS/244/28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We offer to the star formation community the third installment of the Massive Star-forming Regions (MSFRs) Omnibus X-ray Catalog (MOXC3), a compilation of X-ray point sources detected in 50 archival Chandra Advanced CCD Imaging Spectrometer observations of 14 Galactic MSFRs and surrounding fields. The MOXC3 MSFRs are NGC2264, NGC6193, RCW108-IR, AurOB1, DR15, NGC6231, Berkeley87, NGC6357, AFGL4029, hPer (NGC869), NGC281, Onsala2S, G305, and RCW49 (Wd2); they have distances of 0.7-4.2kpc. Most exhibit clumped or clustered young stellar populations; several contain at least two distinct massive young stellar clusters. The total MOXC3 catalog includes 27923 X-ray point sources. We take great care to identify even the faintest X-ray point sources across these fields. This allows us to remove this point source light, revealing diffuse X-ray structures that pervade and surround MSFRs, often generated by hot plasmas from massive star feedback. As we found in MOXC1 and MOXC2, diffuse X-ray emission is traceable in all MOXC3 MSFRs; here we perform spectral fitting to investigate the origins of selected diffuse regions. Once again, MOXC3 shows the value of high spatial resolution X-ray studies of MSFRs enabled by Chandra.
- ID:
- ivo://CDS.VizieR/J/MNRAS/274/1165
- Title:
- The 2RE Source Catalogue
- Short Name:
- J/MNRAS/274/1165
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/ApJS/245/19
- Title:
- Thermonuclear burst oscillations (TBOs) with RXTE
- Short Name:
- J/ApJS/245/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe a blind uniform search for thermonuclear burst oscillations (TBOs) in the majority of Type I bursts observed by the Rossi X-ray Timing Explorer (RXTE) (2118 bursts from 57 neutron stars). We examined 2-2002Hz power spectra from the Fourier transform in sliding 0.5-2s windows, using fine-binned light curves in the 2-60keV energy range. The significance of the oscillation candidates was assessed by simulations which took into account light-curve variations, dead time, and the sliding time windows. Some of our sources exhibited multi-frequency variability at <~15Hz that cannot be readily removed with light-curve modeling and may have an astrophysical (non-TBO) nature. Overall, we found that the number and strength of potential candidates depends strongly on the parameters of the search. We found candidates from all previously known RXTE TBO sources, with pulsations that had been detected at similar frequencies in multiple independent time windows, and discovered TBOs from SAXJ1810.8-2658. We could not confirm most previously reported tentative TBO detections or identify any obvious candidates just below the detection threshold at similar frequencies in multiple bursts. We computed fractional amplitudes of all TBO candidates and placed upper limits on non-detections. Finally, for a few sources we noted a small excess of candidates with powers comparable to fainter TBOs, but appearing in single independent time windows at random frequencies. At least some of these candidates may be noise spikes that appear interesting due to selection effects. The potential presence of such candidates calls for extra caution if claiming single-window TBO detections.
- ID:
- ivo://CDS.VizieR/J/ApJS/179/360
- Title:
- Thermonuclear X-ray bursts observed by RXTE
- Short Name:
- J/ApJS/179/360
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a sample of 1187 thermonuclear (type-I) X-ray bursts from public (archival) observations of 48 low-mass X-ray binaries accreting neutron stars by the Rossi X-ray Timing Explorer, spanning 1996 January - 2007 June 3. For each burst, we list results of analysis of data from the Proportional Counter Array, including observed count rates, time-resolved spectroscopy, evolution of the burst lightcurve, and details of the persistent flux and source spectral state at the time of the burst.
- ID:
- ivo://CDS.VizieR/J/MNRAS/301/881
- Title:
- The ROSAT brightest cluster sample - I.
- Short Name:
- J/MNRAS/301/881
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 90 per cent flux-complete sample of the 201 X-ray-brightest clusters of galaxies in the northern hemisphere ({delta}>=0{deg}), at high Galactic latitudes (|b|>= 20{deg}), with measured redshifts z<=0.3 and fluxes higher than 4.4x10^-12^erg/cm^2^/s in the 0.112.4 keV band. The sample, called the ROSAT Brightest Cluster Sample (BCS), is selected from ROSAT All-Sky Survey data and is the largest X-ray-selected cluster sample compiled to date. In addition to Abell clusters, which form the bulk of the sample, the BCS also contains the X-ray-brightest Zwicky clusters and other clusters selected from their X-ray properties alone. Effort has been made to ensure the highest possible completeness of the sample and the smallest possible contamination by non-cluster X-ray sources. X-ray fluxes are computed using an algorithm tailored for the detection and characterization of X-ray emission from galaxy clusters. These fluxes are accurate to better than 15 per cent (mean 1{sigma} error).
