- ID:
- ivo://CDS.VizieR/J/ApJ/636/765
- Title:
- Second IBIS/ISGRI soft gamma-ray survey catalog
- Short Name:
- J/ApJ/636/765
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we report the second soft gamma-ray source catalog obtained with the IBIS/ISGRI gamma-ray imager on board the INTEGRAL satellite. The scientific data set is based on more than 10Ms of high-quality observations performed during the first 2 years of Core Program and public IBIS/ISGRI observations, and covers 50% of the whole sky. The main aim of the first survey was to scan systematically, for the first time at energies above 20keV, the whole Galactic plane to achieve a limiting sensitivity of 1mCrab in the central radian. The target of the second year of the INTEGRAL mission lifetime was to expand as much as possible our knowledge of the soft gamma-ray sky, with the same limiting sensitivity, to at least 50% of the whole sky, mainly by including a substantial coverage of extragalactic fields. This catalog comprises more than 200 high-energy sources detected in the energy range 20-100keV, including new transients not active during the first year of operation, faint persistent objects revealed with longer exposure time, and several Galactic and extragalactic sources in sky regions not observed in the first survey. The mean position error for all the sources detected with significance above 10{sigma} is 40", enough to identify most of them with a known X-ray counterpart and to unveil the nature of most of the strongly absorbed ones, even though they are very difficult to detect in X-rays.
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- ID:
- ivo://CDS.VizieR/J/A+A/505/417
- Title:
- Second INTEGRAL AGN catalogue
- Short Name:
- J/A+A/505/417
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The INTEGRAL mission provides a large data set for studying the hard X-ray properties of AGN and allows testing the unified scheme for AGN. We present analysis of INTEGRAL IBIS/ISGRI, JEM-X, and OMC data for 199 AGN that have been reported to be detected by INTEGRAL above 20keV. The data analysed here allow a significant spectral extraction on 148 objects and optical variability study of 57 AGN. The slopes of the hard X-ray spectra of Seyfert 1 and Seyfert 2 galaxies are found to be consistent within the uncertainties, whereas lower luminosities are measured for the more absorbed/type 2 AGN. The intermediate Seyfert 1.5 objects exhibit hard X-ray spectra consistent with those of Seyfert 1. When applying a Compton reflection model, the underlying continua appear still the same in Seyfert 1 and 2 with photon index 2, and the reflection strength is about R=1, when assuming different inclination angles. A significant correlation is found between the hard X-ray and optical luminosity and the mass of the central black hole in the sense that the more luminous objects appear to be more massive. There is also a general trend for the absorbed sources and type 2 AGN to have lower Eddington ratios. The black hole mass appears to form a fundamental plane together with the optical and X-ray luminosity of the form LV being proportional to LX^0.6^.M^0.2^, similar to that found between radio luminosity LR, LX, and M. The unified model for Seyfert galaxies seems to hold, showing in hard X-rays that the central engine is the same in Seyfert 1 and 2 but seen under different inclination angles and absorption.
- ID:
- ivo://CDS.VizieR/VII/261
- Title:
- Second Kiso Survey for UV-Excess Galaxies (KUG2)
- Short Name:
- VII/261
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have continued the surveys of ultraviolet-excess galaxies (abbreviated as KUGs) with the 105cm Kiso Schmidt telescope for two decades. The first survey was summarized in Takase and Miyauchi-Isobe (1993b), which lists 8,104 KUGs in 5,100 square degrees area. The second survey has been followed the first survey with a similar method, and lists 1,985 objects in 1,860 square degrees area in 6 papers (Miyauchi-Isobe and Maehara 1998-2006), supplementing the first survey. The second survey is completed with this lists, because the similar method (i.e. to use photographic plates) has become impossible at Kiso Schmidt telescope. There are some differences in photographic plates used and the observation condition in the surveys, such as emulsions, exposures or seeing sizes. Thus the homogeneity of the KUG survey is rather low, but its catalogue forms a somewhat large collection of UV-excess/blue galaxies. In these circumstances, we intend to merge both catalogues, upon requests from investigators working in follow-up observations of these galaxies. In the process of catalogue merging, we met a systematic difference between the first (KUG1) and the second (KUG2) surveys in overall properties of objects, such as brightness, degree of UV-excess and morphological type. This mainly originates from differences in the observation condition and personal errors in the survey. We scrutinize and discuss those differences and errors, and finally merge into a comprehensive catalogue of KUGs (KUG2000) in the machine-readable form including near ten thousand UV-excess galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/594/A26
- Title:
- Second Planck Catalogue of Compact Sources (PCCS2)
- Short Name:
- J/A+A/594/A26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Second Planck Catalogue of Compact Sources is a list of discrete objects detected in single-frequency maps from the full duration of the Planck mission and supersedes previous versions. It consists of compact sources, both Galactic and extragalactic, detected over the entire sky. Compact sources detected in the lower frequency channels are assigned to the PCCS2, while at higher frequencies they are assigned to one of two subcatalogues, the PCCS2 or PCCS2E, depending on their location on the sky. The first of these (PCCS2) covers most of the sky and allows the user to produce subsamples at higher reliabilities than the target 80% integral reliability of the catalogue. The second (PCCS2E) contains sources detected in sky regions where the diffuse emission makes it difficult to quantify the reliability of the detections. Both the PCCS2 and PCCS2E include polarization measurements, in the form of polarized flux densities, or upper limits, and orientation angles for all seven polarization-sensitive Planck channels. The improved data-processing of the full-mission maps and their reduced noise levels allow us to increase the number of objects in the catalogue, improving its completeness for the target 80% reliability as compared with the previous versions, the PCCS and the Early Release Compact Source Catalogue (ERCSC).
- ID:
- ivo://CDS.VizieR/J/A+A/588/A103
- Title:
- Second ROSAT all-sky survey (2RXS) source catalog
- Short Name:
- J/A+A/588/A103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the second ROSAT all-sky survey source catalogue, hereafter referred to as the 2RXS catalogue. This is the second publicly released ROSAT catalogue of point-like sources obtained from the ROSAT all-sky survey (RASS) observations performed with the position-sensitive proportional counter (PSPC) between June 1990 and August 1991, and is an extended and revised version of the bright and faint source catalogues. We used the latest version of the RASS processing to produce overlapping X-ray images of 6.4 by 6.4 degrees sky regions. To create a source catalogue, a likelihood-based detection algorithm was applied to these, which accounts for the variable point-spread function (PSF) across the PSPC field of view. Improvements in the background determination compared to 1RXS were also implemented. X-ray control images showing the source and background extraction regions were generated, which were visually inspected. Simulations were performed to assess the spurious source content of the 2RXS catalogue. X-ray spectra and light curves were extracted for the 2RXS sources, with spectral and variability parameters derived from these products. We obtained about 135,000 X-ray detections in the 0.1-2.4keV energy band down to a likelihood threshold of 6.5, as adopted in the 1RXS faint source catalogue. Our simulations show that the expected spurious content of the catalogue is a strong function of detection likelihood, and the full catalogue is expected to contain about 30 per cent spurious detections. A more conservative likelihood threshold of 9, on the other hand, yields about 71,000 detections with a 5 per cent spurious fraction. We recommend thresholds appropriate to the scientific application. X-ray images and overlaid X-ray contour lines provide an additional user product to evaluate the detections visually, and we performed our own visual inspections to flag uncertain detections. Intra-day variability in the X-ray light curves was quantified based on the normalised excess variance and a maximum amplitude variability analysis. X-ray spectral fits were performed using three basic models, a power law, a thermal plasma emission model, and black-body emission. Thirty-two large extended regions with diffuse emission and embedded point sources were identified and excluded from the present analysis. The 2RXS catalogue provides the deepest and cleanest X-ray all-sky survey catalogue in advance of eROSITA.
- ID:
- ivo://CDS.VizieR/IX/30
- Title:
- Second ROSAT PSPC Catalog
- Short Name:
- IX/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue contains sources from PSPC-ROSAT (Position-Sensitive Proportional Counter aboard the Roentgen Satellite), as provided by Max-Planck Institut fuer extraterrestrische Physik (MPE). It supersedes the 1994 version (Cat. <IX/11>) The current release of the catalog is comprised of results from 4093 sequences (sky coverage of 14.5%). The complete version contains entries for 95,331 detections whereas the short version has 43,156 detections. 2189 obvious sources were not detected by the automated Standard Analysis Software System (SASS), and are not yet contained in this catalogue. These data have been screened by ROSAT data centers in the US, Germany, and the UK as a step in the production of the ROSAT RESULTS ARCHIVE. The RRA contains extracted source and associated products with an indication of reliability for the primary parameters.
- ID:
- ivo://CDS.VizieR/J/AJ/126/2562
- Title:
- Second VLBA calibrator survey: VCS2
- Short Name:
- J/AJ/126/2562
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents an extension of the Very Long Baseline Array Calibrator Survey, called VCS2, containing 276 sources. This survey fills in regions of the sky that were not completely covered by the previous VCS1 calibrator survey. The VCS2 survey includes calibrator sources near the Galactic plane, -30{deg}<DE<-45{deg}, and VLA calibrators. The positions have been derived from astrometric analysis of the group delays measured at 2.3 and 8.4 GHz using the Goddard Space Flight Center CALC/SOLVE package. From the VLBA snapshot observations, images of the calibrators are available, and each source is given a quality code for anticipated use. The VCS2 catalog is available from the NRAO Web site.
- ID:
- ivo://CDS.VizieR/J/ApJ/786/59
- Title:
- SED fitting results of HETDEX pilot survey
- Short Name:
- J/ApJ/786/59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use broadband photometry extending from the rest-frame UV to the near-IR to fit the individual spectral energy distributions of 63 bright (L(Ly{alpha})>10^43^ erg/s) Ly{alpha} emitting galaxies (LAEs) in the redshift range 1.9<z<3.6. We find that these LAEs are quite heterogeneous, with stellar masses that span over three orders of magnitude, from 7.5<log M/M_{sun}_<10.5. Moreover, although most LAEs have small amounts of extinction, some high-mass objects have stellar reddenings as large as E(B-V)~0.4. Interestingly, in dusty objects the optical depths for Ly{alpha} and the UV continuum are always similar, indicating that Ly{alpha} photons are not undergoing many scatters before escaping their galaxy. In contrast, the ratio of optical depths in low-reddening systems can vary widely, illustrating the diverse nature of the systems. Finally, we show that in the star-formation-rate-log-mass diagram, our LAEs fall above the "main-sequence" defined by z~3 continuum selected star-forming galaxies. In this respect, they are similar to submillimeter-selected galaxies, although most LAEs have much lower mass.
- ID:
- ivo://CDS.VizieR/J/A+A/514/A11
- Title:
- SEDs in ADFS (AKARI Deep Field South)
- Short Name:
- J/A+A/514/A11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the nature and properties of far-infrared (FIR) sources in the AKARI Deep Field South (ADF-S). We performed an extensive search for the counterparts to 1000 ADF-S objects brighter than 0.0301Jy in the WIDE-S (90um) AKARI band in the public databases (NED and SIMBAD). We analyzed the properties of the resulting sample: statistics of the identified objects, quality of position determination of the ADF-S sources, their number counts, redshift distribution, and comparison of morphological types, when the corresponding information was available. We performed a simplified analysis of the clustering properties of the ADF-S sources and compiled spectral energy distributions (SEDs) of objects with the highest quality photometry, using three different models. Among 1000 investigated ADF-S sources, 545 were identified with sources at other wavelengths in public databases. From them, 518 are known galaxies and 343 of these were previously known as infra-red sources. Among the remaining sources, there are two quasars and both infrared and radio sources of unknown origin. Among six stellar identifications, at least five are probably the effect of contamination. We measured the redshifts of 48 extragalactic objects and determined the morphological types of 77 galaxies. We present SED models of 47 sources with sufficiently good photometric data. Conclusions: We conclude that the bright FIR point sources observed in the ADF-S are mostly nearby galaxies. Their properties are very similar to the properties of the local population of optically bright galaxies, except for unusually high ratio of peculiar or interacting objects and a lower percentage of elliptical galaxies. The percentage of lenticular galaxies is the same as in the optically bright population, which suggests that galaxies of this type may frequently contain a significant amount of cool dust. It is possible that source confusion plays a significant role in more than 34% of measurements. The SEDs correspond to a variety of galaxy types, from very actively star forming to very quiescent. The AKARI long wavelength bands data have enabled us to determine for the first time that these galaxies are objects with very cool dust.
- ID:
- ivo://CDS.VizieR/J/ApJ/738/69
- Title:
- SEDs of galaxies at 3.8<z<5 in GOODS
- Short Name:
- J/ApJ/738/69
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present evidence for strong H{alpha} emission in galaxies with spectroscopic redshifts in the range of 3.8<z<5.0 over the Great Observatories Origins Deep Survey fields. Among 74 galaxies detected in the Spitzer IRAC 3.6 and 4.5um bands, more than 70% of the galaxies show clear excess at 3.6um compared to the expected flux density from stellar continuum only. We provide evidence that this 3.6um excess is due to H{alpha} emission redshifted into the 3.6um band, and classify these 3.6um excess galaxies to be H{alpha} emitter (HAE) candidates. The selection of HAE candidates using an excess in broadband filters is sensitive to objects whose rest-frame H{alpha} equivalent width (EW) is larger than 350{AA}. The H{alpha} inferred star formation rates (SFRs) of the HAEs range between 20 and 500M_{sun}_/yr and are a factor of ~6 larger than SFRs inferred from the UV continuum. The ratio between the H{alpha} luminosity and UV luminosity of HAEs is also on average larger than that of local starbursts.
