- ID:
- ivo://CDS.VizieR/J/ApJ/715/429
- Title:
- First Fermi-LAT AGN catalog (1LAC)
- Short Name:
- J/ApJ/715/429
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first catalog of active galactic nuclei (AGNs) detected by the Large Area Telescope (LAT), corresponding to 11 months of data collected in scientific operation mode. The First LAT AGN Catalog (1LAC) includes 671 {gamma}-ray sources located at high Galactic latitudes (|b|>10{deg}) that are detected with a test statistic greater than 25 and associated statistically with AGNs. Some LAT sources are associated with multiple AGNs, and consequently, the catalog includes 709 AGNs, comprising 300 BL Lacertae objects, 296 flat-spectrum radio quasars, 41 AGNs of other types, and 72 AGNs of unknown type. We also classify the blazars based on their spectral energy distributions as archival radio, optical, and X-ray data permit. In addition to the formal 1LAC sample, we provide AGN associations for 51 low-latitude LAT sources and AGN "affiliations" (unquantified counterpart candidates) for 104 high-latitude LAT sources without AGN associations.
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- ID:
- ivo://CDS.VizieR/J/ApJ/819/44
- Title:
- First Fermi-LAT Inner Galaxy point source catalog
- Short Name:
- J/ApJ/819/44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Fermi Large Area Telescope (LAT) has provided the most detailed view to date of the emission toward the Galactic center (GC) in high-energy {gamma}-rays. This paper describes the analysis of data taken during the first 62 months of the mission in the energy range 1-100GeV from a 15{deg}x15{deg} region about the direction of the GC. Specialized interstellar emission models (IEMs) are constructed to enable the separation of the {gamma}-ray emissions produced by cosmic ray particles interacting with the interstellar gas and radiation fields in the Milky Way into that from the inner ~1kpc surrounding the GC, and that from the rest of the Galaxy. A catalog of point sources for the 15{deg}x15{deg} region is self-consistently constructed using these IEMs: the First Fermi-LAT Inner Galaxy Point Source Catalog (1FIG). The spatial locations, fluxes, and spectral properties of the 1FIG sources are presented, and compared with {gamma}-ray point sources over the same region taken from existing catalogs. After subtracting the interstellar emission and point-source contributions a residual is found. If templates that peak toward the GC are used to model the positive residual the agreement with the data improves, but none of the additional templates tried account for all of its spatial structure. The spectrum of the positive residual modeled with these templates has a strong dependence on the choice of IEM.
- ID:
- ivo://nasa.heasarc/gpa
- Title:
- First Galactic Plane Survey at 8.35 and 14.35 GHz
- Short Name:
- GP8.35/14.35
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains results from the first Galactic Plane (GP) Survey at 8.35 and 14.35 GHz (3.6 and 2.1 cm). In this project, the first images of the GP in the galactic latitude range |b| < 5 degrees and the galactic longitude range -15 degrees < l < 255 degrees at 8.35 and 14.35 GHz were presented. These observations used the National Radio Astronomy Observatory-NASA Green Bank Earth Station to survey the sky simultaneously at these two frequencies. These GPA data are the first results from the GP Survey observations, a program to monitor this portion of the sky at 8.35 and 14.35 GHz. The GP Survey series is intended to detect short-lived radio sources. In their published paper, the authors presented four independent observations of the Galactic plane, combined to provide a set of reference images of the Galactic plane. This first GPA survey covers 0.82 steradian (6.5%) of the sky. This table conatins a source list of all sources which were brighter than 0.9 Jy at 8.35 GHz and also of all sources brighter than 2.5 Jy at 14.35 GHz. The FITS format images, residual images, source lists, and archive data are available over the internet at <a href="http://www.gb.nrao.edu/~glangsto/GPA">http://www.gb.nrao.edu/~glangsto/GPA</a> . This table was created by the HEASARC in December 2004 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AJ/119/2801/">CDS catalog J/AJ/119/2801/</a>, tables s8.dat and s14.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/ApJ/607/L33
- Title:
- First IBIS Catalog: 20-100keV
- Short Name:
- J/ApJ/607/L33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the first high-energy survey catalog obtained with the IBIS gamma-ray imager on board INTEGRAL. The analysis has been performed on the first-year Core Program ISGRI data comprising both Galactic Plane Scan and Galactic Centre Deep Exposure pointings for a total exposure time exceeding 5Ms. This initial survey has revealed the presence of ~120 sources detected with the unprecedented sensitivity of ~1mCrab in the energy range 20-100keV. Each source is located to an accuracy between 1' and 3', depending on its brightness. The outstanding IBIS capability to locate soft {gamma}-ray emitters has allowed us to identify most of the detected sources with already known Galactic X-ray binary systems, while 28 of the objects are of unknown nature.
- ID:
- ivo://CDS.VizieR/J/A+A/438/1175
- Title:
- First INTEGRAL SPI-ACS Gamma-Ray Burst Catalogue
- Short Name:
- J/A+A/438/1175
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the sample of gamma-ray bursts detected with the anti-coincidence shield ACS of the spectrometer SPI on-board INTEGRAL for the first 26.5 months of mission operation (up to Jan 2005). SPI-ACS works as a nearly omnidirectional gamma-ray burst detector above ~80keV but lacks spatial and spectral information. In this catalogue, the properties derived from the 50ms light curves (e.g., T_90_, C_max_, C_int_, variability, V/V_max_) are given for each candidate burst in the sample. A strong excess of very short events with durations <0.25s is found. This population is shown to be significantly different from the short- and long-duration burst sample by means of the intensity distribution and V/V_max_ test and is certainly connected with cosmic ray hits in the detector. A rate of 0.3 true gamma-ray bursts per day is observed.
- ID:
- ivo://CDS.VizieR/J/A+AS/141/469
- Title:
- First list of the Karachentsev catalog
- Short Name:
- J/A+AS/141/469
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present HI observations of the galaxies in the first list of the Karachentsev catalog of previously unknown nearby dwarf galaxies (Karachentseva & Karachentsev, 1998, Cat. <J/A+AS/127/409>). This survey covers all known nearby galaxy groups within the Local Volume (i.e. within 10Mpc) and their environment, that is about 25% of the total sky. A total of 257 galaxies have been observed with a detection rate of 60%. We searched a frequency band corresponding to heliocentric radial velocities from -470km/s to ~+4000km/s. Non-detections are either due to limited coverage in radial velocity, confusion with Local HI (mainly in the velocity range -140km/s to +20km/s), or lack of sensitivity for very weak emission. 25% of the detected galaxies are located within the Local Volume. Those galaxies are dwarf galaxies judged by their optical linear diameter (1.4+/-0.2kpc on the average), their mean total HI mass (4.6x10^7^M_{sun}_), and their observed linewidths (39km/s).
- ID:
- ivo://CDS.VizieR/J/ApJ/859/4
- Title:
- First-look analysis of {rho} Oph-A at 850um
- Short Name:
- J/ApJ/859/4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 850{mu}m imaging polarimetry data of the {rho} Oph-A core taken with the Submillimeter Common-User Bolometer Array-2 (SCUBA-2) and its polarimeter (POL-2) as part of our ongoing survey project, B-fields In STar forming RegiOns (BISTRO). The polarization vectors are used to identify the orientation of the magnetic field projected on the plane of the sky at a resolution of 0.01pc. We identify 10 subregions with distinct polarization fractions and angles in the 0.2pc {rho} Oph-A core; some of them can be part of a coherent magnetic field structure in the {rho} Oph region. The results are consistent with previous observations of the brightest regions of {rho} Oph-A, where the degrees of polarization are at a level of a few percent, but our data reveal for the first time the magnetic field structures in the fainter regions surrounding the core where the degree of polarization is much higher (>5%). A comparison with previous near-infrared polarimetric data shows that there are several magnetic field components that are consistent at near-infrared and submillimeter wavelengths. Using the Davis-Chandrasekhar-Fermi method, we also derive magnetic field strengths in several subcore regions, which range from approximately 0.2 to 5mG. We also find a correlation between the magnetic field orientations projected on the sky and the core centroid velocity components.
- ID:
- ivo://CDS.VizieR/J/AJ/128/1
- Title:
- First Look Survey: NOAO R-band Mosaic
- Short Name:
- J/AJ/128/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present R-band images covering more than 11 square degrees of sky that were obtained in preparation for the Spitzer Space Telescope First-Look Survey (FLS). The FLS was designed to characterize the mid-infrared sky at depths 2 orders of magnitude deeper than previous surveys. The extragalactic component is the first cosmological survey done with Spitzer. Source catalogs extracted from the R-band images are also presented. The R-band images were obtained using the Mosaic-1 camera on the 4m Mayall Telescope of the Kitt Peak National Observatory. Two relatively large regions of the sky were observed to modest depth: the main FLS extragalactic field (17h18m00s, +59{deg}30'00.0"[J2000]; l=88.3{deg}, b=+34.9{deg}) and the ELAIS-N1 field (16h10m01s, +54{deg}30'36.0"; l=84.2{deg}, b=+44.9{deg}). While both these fields were in early plans for the FLS, only a single deep-pointing test observation was made at the ELAIS-N1 location. The larger Legacy program SWIRE will include this region among its surveyed areas. The data products of our KPNO imaging (images and object catalogs) are made available to the community through the World Wide Web (via the Spitzer Science Center and NOAO Science Archive, http://ssc.spitzer.caltech.edu/fls/). The overall quality of the images is high. The measured positions of sources detected in the images have rms uncertainties in their absolute positions on the order of 0.35" with possible systematic offsets on the order of 0.1", depending on the reference frame of comparison. The relative astrometric accuracy is much better than 1/10 of an arcsecond. Typical delivered image quality in the images is 1.1" full width at half-maximum. The images are relatively deep, since they reach a median 5{sigma} depth limiting magnitude of R=25.5 (Vega) as measured within a 1.35 FWHM aperture, for which the signal-to-noise ratio (S/N) is maximal. Catalogs have been extracted with SExtractor, using thresholds in area and flux for which the number of false detections is below 1% at R=25. Only sources with S/N>3 have been retained in the final catalogs. Comparing the galaxy number counts from our images with those of deeper R-band surveys, we estimate that our observations are 50% complete at R=24.5. These limits in depth are sufficient to identify a substantial fraction of the infrared sources that will be detected by Spitzer.
- ID:
- ivo://CDS.VizieR/J/ApJ/757/51
- Title:
- FIRST-2MASS dust-reddened QSO spectra
- Short Name:
- J/ApJ/757/51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a sample of 120 dust-reddened quasars identified by matching radio sources detected at 1.4GHz in the Faint Images of the Radio Sky at Twenty Centimeters survey (FIRST) with the near-infrared Two Micron All Sky Survey catalog (2MASS) and color-selecting red sources. Optical and/or near-infrared spectroscopy provide broad wavelength sampling of their spectral energy distributions that we use to determine their reddening, characterized by E(B-V). We demonstrate that the reddening in these quasars is best described by Small-Magellanic-Cloud-like dust. This sample spans a wide range in redshift and reddening (0.1<~z<~3, 0.1<~E(B-V)<~1.5), which we use to investigate the possible correlation of luminosity with reddening. At every redshift, dust-reddened quasars are intrinsically the most luminous quasars. We interpret this result in the context of merger-driven quasar/galaxy co-evolution where these reddened quasars are revealing an emergent phase during which the heavily obscured quasar is shedding its cocoon of dust prior to becoming a "normal" blue quasar. When correcting for extinction, we find that, depending on how the parent population is defined, these red quasars make up <~15%-20% of the luminous quasar population. We estimate, based on the fraction of objects in this phase, that its duration is 15%-20% as long as the unobscured, blue quasar phase.
- ID:
- ivo://CDS.VizieR/J/ApJ/607/60
- Title:
- FIRST-2MASS faint sources
- Short Name:
- J/ApJ/607/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have constructed a sample of bright near-infrared sources that are detected at radio wavelengths but undetected on the first-generation Palomar Observatory Sky Survey (POSSI) plates in order to search for a population of dust-obscured quasars. Optical and infrared spectroscopic follow-up of the sample has led to the discovery of 17 heavily reddened quasars (B-K>6.5), 14 of which are reported here for the first time. This has allowed us to define a region in the R-K, J-K color plane in which 50% of the radio-selected objects are highly reddened quasars. We compare the surface density of this previously overlooked population to that of ultraviolet-excess radio-selected quasars, finding that they make up ~20% of the total quasar population for K<~15.5.