- ID:
- ivo://CDS.VizieR/J/A+A/608/A68
- Title:
- TeV/non-TeV BL Lacs multi-lambda fluxes
- Short Name:
- J/A+A/608/A68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have collected the most complete multi-wavelength (6.0-6.0E^-18^cm) dataset of very high energy (VHE) gamma-ray emitting (TeV) BL Lacs, which are the most numerous extragalactic VHE sources. Using significant correlations between different bands, we aim to identify the best TeV BL Lac candidates that can be discovered by the current and next generation of imaging air Cherenkovtelescopes. We formed five datasets from lower energy data, i.e. radio, mid-infrared, optical, X-rays, and GeV gamma-ray, and five VHE gamma-ray datasets to perform a correlation study between different bands and to construct the prediction method. The low energy datasets were averaged for individual sources, while the VHE gamma-ray data were divided into subsets according to the flux state of the source. We then looked for significant correlations and determined their best-fit parameters. Using the best-fit parameters we predicted the level of VHE gamma-ray flux for a sample of 182 BL Lacs, which have not been detected at TeV energies. We identified the most promising TeV BL Lac candidates based on the predicted VHE gamma-ray flux for each source. We found 14 significant correlations between radio, mid-infrared, optical, gamma-ray, and VHE gamma-ray bands. The correlation between optical and VHE gamma-ray luminosity is established for the first time. We attribute this to the more complete sample and more accurate handling of host galaxy flux in our work. We found nine BL Lac candidates whose predicted VHE gamma-ray flux is high enough for detection in less than 25 hours with current imaging air Cherenkov telescopes.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/357/1231
- Title:
- Texas-Oxford NVSS (TONS) radio galaxies
- Short Name:
- J/MNRAS/357/1231
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a clustering analysis of the Texas-Oxford NVSS Structure (TONS) radio galaxy redshift survey. This complete flux-limited survey consists of 268 radio galaxies with spectroscopic redshifts in three separate regions of the sky covering a total of 165{deg}^2^. By going to faint radio flux densities (S_1.4_>=3mJy) but imposing relatively bright optical limits (E~R~19.5), the TONS sample is optimized for looking at the clustering properties of low-luminosity radio galaxies in a region of moderate (0<=z<=0.5) redshifts. Description:
3713. The ACS-GC catalog
- ID:
- ivo://CDS.VizieR/J/ApJS/200/9
- Title:
- The ACS-GC catalog
- Short Name:
- J/ApJS/200/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Advanced Camera for Surveys General Catalog (ACS-GC), a photometric and morphological database using publicly available data obtained with the Advanced Camera for Surveys (ACS) instrument on the Hubble Space Telescope. The goal of the ACS-GC database is to provide a large statistical sample of galaxies with reliable structural and distance measurements to probe the evolution of galaxies over a wide range of look-back times. The ACS-GC includes approximately 470000 astronomical sources (stars + galaxies) derived from the AEGIS, COSMOS, GEMS, and GOODS surveys. Galapagos code (Hausler et al. 2011ASPC..442..155H) was used to construct photometric (SExtractor) and morphological (Galfit) catalogs. The analysis assumes a single Sersic model for each object to derive quantitative structural parameters. We include publicly available redshifts from the DEEP2, COMBO-17, TKRS, PEARS, ACES, CFHTLS, and zCOSMOS surveys to supply redshifts (spectroscopic and photometric) for a considerable fraction (~74%) of the imaging sample. The ACS-GC includes color postage stamps, Galfit residual images, and photometry, structural parameters, and redshifts combined into a single catalog.
- ID:
- ivo://CDS.VizieR/J/AJ/156/191
- Title:
- The ages of M31 star clusters: SED versus CMD
- Short Name:
- J/AJ/156/191
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It is well-known that fitting Color-Magnitude Diagrams (CMDs) to theoretical isochrones is the main method to determine star cluster ages. However, when CMDs are not available, the Spectral Energy Distribution (SED)-fitting technique is the only other approach, although it suffers the age-metallicity-reddening degeneracy. In this work, we gather the ages, metallicities, and masses of dozens of M31 star clusters from the CMD-fitting with Hubble Space Telescope images from the literature for comparison. We check the reliability of the SED-fitting results with different models, i.e., Bruzual & Charlot (2003MNRAS.344.1000B) model (BC03), Galaxy Evolutionary Synthesis Models (GALEV), and Advanced Stellar Population Synthesis (ASPS) for the simple stellar populations (SSPs) with single stars (ss)-SSP/binary-star (bs)-SSPs models. The photometry bands includes the Galaxy Evolution Explorer GALEX FUV/NUV bands, optical/near-infrared UBVRIJHK bands, as well as the Wide-field Infrared Survey Explorer (WISE) W1/W2 bands. The comparisons show that the SED-fitting ages agree well with the CMD-fitting ages, either with the fixed metallicity or with the free metallicity for both the BC03 and the GALEV model. However, for the ASPS models, it seems that SED-fitting results are systematically older than the CMD ages, especially for the ages log t<9.0 (year). The fitting also shows that the GALEX FUV/NUV-band are more important than the WISE W1/W2 for constraining the ages, which confirms the previous findings. We also derived the masses of our sample star clusters from the BC03 and GALEV models and it is found that the values agree well with those in the literature.
- ID:
- ivo://CDS.VizieR/J/MNRAS/485/1188
- Title:
- The ALMA Calibrator Catalogue
- Short Name:
- J/MNRAS/485/1188
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new catalogue of ALMA observations, the ALMA Calibrator Catalogue (ACC), collecting 3361 bright, compact radio sources, mostly blazars, used as calibrators. These sources were observed between 2011 May and 2018 July, for a total of 47115 pointings in different bands and epochs. A search in the online data bases yielded redshift measurements for 2245 sources.
- ID:
- ivo://CDS.VizieR/J/A+A/411/391
- Title:
- The AMIGA project. Revised positions for CIG galaxies
- Short Name:
- J/A+A/411/391
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present revised positions for the 1051 galaxies belonging to the Karachentseva Catalog of Isolated Galaxies (CIG, Cat. <VII/82>). New positions were calculated by applying SExtractor to the Digitized Sky Survey CIG fields with a spatial resolution of 1.2". We visually checked the results and for 118 galaxies had to recompute the assigned positions due to complex morphologies (e.g. distorted isophotes, undefined nuclei, knotty galaxies) or the presence of bright stars. We found differences between older and newer positions of up to 38" with a mean value of 2.96" relative to SIMBAD and up to 38" and 2.42" respectively relative to UZC (Cat. <J/PASP/111/438>). Based on star positions from the APM catalog (Cat. <I/267>) we determined that the DSS astrometry of five CIG fields has a mean offset in ({alpha},{delta}) of (-0.90", 0.93") with a dispersion of 0.4". These results have been confirmed using the 2MASS All-Sky Catalog of Point Sources (Cat. <II/246>). The intrinsic errors of our method combined with the astrometric ones are of the order of 0.5".
- ID:
- ivo://CDS.VizieR/J/MNRAS/278/1025
- Title:
- The APM Bright Galaxy Catalogue
- Short Name:
- J/MNRAS/278/1025
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The APM Bright Galaxy Catalogue lists positions, magnitudes, shapes and morphological types for 14,681 galaxies brighter than b(J) magnitude 16.44 over a 4,180 square degree area of the southern sky. Galaxy and stellar images have been located from glass copy plates of the United Kingdom Schmidt Telescope (UKST) IIIaJ sky survey using the Automated Photographic Measuring (APM) facility in Cambridge, England. The majority of stellar images are rejected by the regularity of their image surface brightness profiles. Remaining images are inspected by eye on film copies of the survey material and classed as stellar, multiple stellar, galaxy, merger or noise. Galaxies are further classified as elliptical, lenticular, spiral, irregular or uncertain. The 180 survey fields are put onto a uniform photometric system by comparing the magnitudes of galaxies in the overlap regions between neighbouring plates. The magnitude zero-point, photometric uniformity and photographic saturation are checked with CCD photometry. Finally, the completeness and reliability of the catalogue is assessed using various internal tests and by comparing with several independently constructed galaxy catalogues.
- ID:
- ivo://CDS.VizieR/J/ApJS/253/42
- Title:
- The Araucaria Project: deep NIR phot. I.
- Short Name:
- J/ApJS/253/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Deep near-infrared (NIR) J- and K-band photometry of three Local Group dwarf spheroidal galaxies-Fornax, Carina, and Sculptor-is made available for the community. Until now, these data have only been used by the Araucaria Project to determine distances using the tip of the red giant branch and RR Lyrae stars. Now, we present the entire data collection in the form of a database, consisting of accurate J- and K-band magnitudes, sky coordinates, ellipticity measurements, and timestamps of observations, complemented by stars' loci in their reference images. The depth of our photometry reaches about 22 mag at the 5{sigma} level, and is comparable to NIR surveys, such as the UKIRT Infrared Deep Sky Survey (UKIDSS) or the VISTA Hemisphere Survey (VHS). Small overlap with VHS and no overlap with UKIDSS makes our database a unique source of quality photometry.
- ID:
- ivo://CDS.VizieR/J/AJ/157/81
- Title:
- The Arecibo PPS Survey. I. Harvesting ALFALFA
- Short Name:
- J/AJ/157/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a multi-objective campaign of targeted 21 cm H I line observations of sources selected from the Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) survey and galaxies identified by their morphological and photometric properties in the Sloan Digital Sky Survey. The aims of this program have been (1) to confirm the reality of some ALFALFA sources whose enigmatic nature suggest additional multiwavelength observations; (2) to probe the low signal-to-noise ratio (S/N) regime, below the ALFALFA reliability limit; and (3) to explore the feasibility of using optical morphology, color, and surface brightness to identify gas-rich objects in the region of the Pisces-Perseus Supercluster (PPS) whose H I fluxes are below the ALFALFA sensitivity limit at that distance. As expected, the reliability of ALFALFA detections depends strongly on the S/N of the H I line signal and its coincidence with a probable stellar counterpart identified by its optical properties, suggestive of ongoing star formation. The identification of low-mass, star-forming populations enables targeted H I line observations to detect galaxies with H I line fluxes below the ALFALFA sensitivity limits in fixed local volumes (D<100 Mpc). The method explored here serves as the basis for extending the sample of gas-bearing objects as part of the ongoing Arecibo Pisces-Perseus Supercluster Survey (APPSS).
- ID:
- ivo://CDS.VizieR/J/ApJS/199/27
- Title:
- The ATLBS Extended Source Sample
- Short Name:
- J/ApJS/199/27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on the Australia Telescope Low Brightness Survey (ATLBS) we present a sample of extended radio sources and derive morphological properties of faint radio sources. One hundred nineteen radio galaxies form the ATLBS Extended Source Sample (ATLBS-ESS) consisting of all sources exceeding 30" in extent and integrated flux densities exceeding 1mJy. We give structural details along with information on galaxy identifications and source classifications. The ATLBS-ESS, unlike samples with higher flux-density limits, has almost equal fractions of FR-I and FR-II radio galaxies, with a large fraction of the FR-I population exhibiting 3C31-type structures. Significant asymmetry in lobe extents appears to be a common occurrence in the ATLBS-ESS FR-I sources compared with FR-II sources. We present a sample of 22 FR-Is at z>0.5 with good structural information. The detection of several giant radio sources, with size exceeding 0.7Mpc, at z>1 suggests that giant radio sources are not less common at high redshifts. The ESS also includes a sample of 28 restarted radio galaxies.
