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581. Fermi-LAT first source catalog (1FGL)
ID:
ivo://CDS.VizieR/J/ApJS/188/405
Title:
Fermi-LAT first source catalog (1FGL)
Short Name:
J/ApJS/188/405
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of high-energy gamma-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), during the first 11 months of the science phase of the mission, which began on 2008 August 4. The First Fermi-LAT catalog (1FGL) contains 1451 sources detected and characterized in the 100MeV to 100GeV range. Source detection was based on the average flux over the 11 month period, and the threshold likelihood Test Statistic is 25, corresponding to a significance of just over 4{sigma}. The 1FGL catalog includes source location regions, defined in terms of elliptical fits to the 95% confidence regions and power-law spectral fits as well as flux measurements in five energy bands for each source. In addition, monthly light curves are provided. Using a protocol defined before launch we have tested for several populations of gamma-ray sources among the sources in the catalog. For individual LAT-detected sources we provide firm identifications or plausible associations with sources in other astronomical catalogs. Identifications are based on correlated variability with counterparts at other wavelengths, or on spin or orbital periodicity. For the catalogs and association criteria that we have selected, 630 of the sources are unassociated. Care was taken to characterize the sensitivity of the results to the model of interstellar diffuse gamma-ray emission used to model the bright foreground, with the result that 161 sources at low Galactic latitudes and toward bright local interstellar clouds are flagged as having properties that are strongly dependent on the model or as potentially being due to incorrectly modeled structure in the Galactic diffuse emission.
582. Fermi LAT second source catalog (2FGL)
ID:
ivo://CDS.VizieR/J/ApJS/199/31
Title:
Fermi LAT second source catalog (2FGL)
Short Name:
J/ApJS/199/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the second catalog of high-energy {gamma}-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), derived from data taken during the first 24 months of the science phase of the mission, which began on 2008 August 4. Source detection is based on the average flux over the 24 month period. The second Fermi-LAT catalog (2FGL) includes source location regions, defined in terms of elliptical fits to the 95% confidence regions and spectral fits in terms of power-law, exponentially cutoff power-law, or log-normal forms. Also included are flux measurements in five energy bands and light curves on monthly intervals for each source. Twelve sources in the catalog are modeled as spatially extended. We provide a detailed comparison of the results from this catalog with those from the first Fermi-LAT catalog (1FGL). Although the diffuse Galactic and isotropic models used in the 2FGL analysis are improved compared to the 1FGL catalog, we attach caution flags to 162 of the sources to indicate possible confusion with residual imperfections in the diffuse model. The 2FGL catalog contains 1873 sources detected and characterized in the 100MeV to 100GeV range of which we consider 127 as being firmly identified and 1171 as being reliably associated with counterparts of known or likely {gamma}-ray-producing source classes.
583. Fermi-LAT sources below 100MeV catalog
ID:
ivo://CDS.VizieR/J/A+A/618/A22
Title:
Fermi-LAT sources below 100MeV catalog
Short Name:
J/A+A/618/A22
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first Fermi Large Area Telescope (LAT) low energy catalog (1FLE) of sources detected in the energy range 30-100MeV. The imaging Compton telescope (COMPTEL) onboard NASA's Compton Gamma-Ray Observatory detected sources below 30MeV, while catalogs of point sources released by the Fermi-LAT and EGRET collaborations use energies above 100MeV. Because the Fermi LAT detects gamma rays with energies as low as 20MeV, we create a list of sources detected in the energy range between 30 and 100MeV, which closes a gap of point source analysis between the COMPTEL catalog and the Fermi-LAT catalogs. One of the main challenges in the analysis of point sources is the construction of the background diffuse emission model. In our analysis, we use a background-independent method to search for point-like sources based on a wavelet transform implemented in the PGWave code. The 1FLE contains 198 sources detected above 3{sigma} significance with eight years and nine months of the Fermi-LAT data. For 187 sources in the 1FLE catalog we have found an association in the Fermi-LAT 3FGL catalog: 148 are extragalactic, 22 are Galactic, and 17 are unclassified in the 3FGL. The ratio of the number of flat spectrum radio quasars (FSRQ) to BL Lacertae (BL Lacs) in 1FLE is three to one, which can be compared with an approximately 1 to 1 ratio for the 3FGL or a one to six ratio for 3FHL. The higher ratio of the FSRQs in the 1FLE is expected due to generally softer spectra of FSRQs relative to BL Lacs. Most BL Lacs in 1FLE are of low-synchrotron peaked blazar type (18 out of 31), which have softer spectra and higher redshifts than BL Lacs on average. Correspondingly, we find that the average redshift of the BL Lacs in 1FLE is higher than in 3FGL or 3FHL. There are 11 sources that do not have associations in the 3FGL. Most of the unassociated sources either come from regions of bright diffuse emission or have several known 3FGL sources in the vicinity, which can lead to source confusion. The remaining unassociated sources have significance less than 4{sigma}.
584. Fermi LAT third source catalog (3FGL)
ID:
ivo://CDS.VizieR/J/ApJS/218/23
Title:
Fermi LAT third source catalog (3FGL)
Short Name:
J/ApJS/218/23
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the third Fermi Large Area Telescope (LAT) source catalog (3FGL) of sources in the 100MeV-300GeV range. Based on the first 4yr of science data from the Fermi Gamma-ray Space Telescope mission, it is the deepest yet in this energy range. Relative to the Second Fermi LAT catalog, the 3FGL catalog incorporates twice as much data, as well as a number of analysis improvements, including improved calibrations at the event reconstruction level, an updated model for Galactic diffuse {gamma}-ray emission, a refined procedure for source detection, and improved methods for associating LAT sources with potential counterparts at other wavelengths. The 3FGL catalog includes 3033 sources above 4{sigma} significance, with source location regions, spectral properties, and monthly light curves for each. Of these, 78 are flagged as potentially being due to imperfections in the model for Galactic diffuse emission. Twenty-five sources are modeled explicitly as spatially extended, and overall 238 sources are considered as identified based on angular extent or correlated variability (periodic or otherwise) observed at other wavelengths. For 1010 sources we have not found plausible counterparts at other wavelengths. More than 1100 of the identified or associated sources are active galaxies of the blazar class; several other classes of non-blazar active galaxies are also represented in the 3FGL. Pulsars represent the largest Galactic source class. From source counts of Galactic sources we estimate that the contribution of unresolved sources to the Galactic diffuse emission is ~3% at 1GeV.
585. Fermi Map: Band 1
ID:
ivo://nasa.heasarc/skyview/fermi
Title:
Fermi Map: Band 1
Short Name:
FERMI
Date:
25 Apr 2025
Publisher:
NASA/GSFC HEASARC
Description:
This survey sums all data observed by the Fermi mission up to week 396. This version of the Fermi survey are intensity maps where the summed counts data are divided by the exposure for each pixel (in cm^2 s) and the area of the pixel. Data is broken into 5 energy bands <ul> <li> 30-100 MeV Band 1 </li> <li> 100-300 MeV Band 2 </li> <li> 300-1000 MeV Band 3 </li> <li> 1-3 GeV Band 4 </li> <li> 3-300 GeV Band 5 </li> </ul> The SkyView data are based upon a Cartesian projection of the counts divided by the exposure maps. In the Cartesian projection pixels near the pole have a much smaller area than pixels on the equator, so these pixels have smaller integrated flux. When creating large scale images in other projections users may wish to make sure to compensate for this effect the flux conserving clip-resampling option. Provenance: Fermi LAT instrument team, NASA Goddard Space Flight Center. This is a service of NASA HEASARC.
586. F-GAMMA 2.64-43GHz radio data over 2007-2015
ID:
ivo://CDS.VizieR/J/A+A/626/A60
Title:
F-GAMMA 2.64-43GHz radio data over 2007-2015
Short Name:
J/A+A/626/A60
Date:
21 Oct 2021
Publisher:
CDS
Description:
The advent of the Fermi gamma-ray space telescope with its superb sensitivity, energy range, and unprecedented capability to monitor the entire 4{pi} sky within less than 2-3 h, introduced a new standard in time domain gamma-ray astronomy. Among several breakthroughs, Fermi has - for the first time - made it possible to investigate, with high cadence, the variability of the broadband spectral energy distribution (SED), especially for active galactic nuclei (AGN). This is necessary for understanding the emission and variability mechanisms in such systems. To explore this new avenue of extragalactic physics the Fermi-GST AGN Multi-frequency Monitoring Alliance (F-GAMMA) programme undertook the task of conducting nearly monthly, broadband radio monitoring of selected blazars, which is the dominant population of the extragalactic gamma-ray sky, from January 2007 to January 2015. In this work we release all the multi-frequency light curves from 2.64 to 43 GHz and first order derivative data products after all necessary post-measurement corrections and quality checks. Along with the demanding task to provide the radio part of the broadband SED in monthly intervals, the F-GAMMA programme was also driven by a series of well-defined fundamental questions immediately relevant to blazar physics. On the basis of the monthly sampled radio SEDs, the F-GAMMA aimed at quantifying and understanding the possible multiband correlation and multi-frequency radio variability, spectral evolution and the associated emission, absorption and variability mechanisms. The location of the gamma-ray production site and the correspondence of structural evolution to radio variability have been among the fundamental aims of the programme. Finally, the programme sought to explore the characteristics and dynamics of the multi-frequency radio linear and circular polarisation. The F-GAMMA ran two main and tightly coordinated observing programmes. The Effelsberg 100 m telescope programme monitoring 2.64, 4.85, 8.35, 10.45, 14.6, 23.05, 32, and 43 GHz, and the IRAM 30 m telescope programme observing at 86.2, 142.3, and 228.9 GHz. The nominal cadence was one month for a total of roughly 60 blazars and targets of opportunity. In a less regular manner the F-GAMMA programme also ran an occasional monitoring with the APEX 12 m telescope at 345 GHz. We only present the Effelsberg dataset in this paper. The higher frequencies data are released elsewhere. The current release includes 155 sources that have been observed at least once by the F-GAMMA programme. That is, the initial sample, the revised sample after the first Fermi release, targets of opportunity, and sources observed in collaboration with a monitoring programme following up on Planck satellite observations. For all these sources we release all the quality-checked Effelsberg multi-frequency light curves. The suite of post-measurement corrections and flagging and a thorough system diagnostic study and error analysis is discussed as an assessment of the data reliability. We also release data products such as flux density moments and spectral indices. The effective cadence after the quality flagging is around one radio SED every 1.3 months. The coherence of each radio SED is around 40 min. The released dataset includes more than 3x104 measurements for some 155 sources over a broad range of frequencies from 2.64 GHz to 43 GHz obtained between 2007 and 2015. The median fractional error at the lowest frequencies (2.64-10.45 GHz) is below 2%. At the highest frequencies (14.6-43 GHz) with limiting factor of the atmospheric conditions, the errors range from 3% to 9%, respectively.
587. Fifth U.S. Naval Observatory CCD Astrograph Catalog (UCAC5) ConeSearch
ID:
ivo://archive.stsci.edu/catalogs/UCAC5
Title:
Fifth U.S. Naval Observatory CCD Astrograph Catalog (UCAC5) ConeSearch
Short Name:
UCAC5 CS
Date:
13 Feb 2020 17:41:52
Publisher:
Space Telescope Science Institute Archive
Description:
New astrometric reductions of the US Naval Observatory CCD Astrograph Catalog (UCAC) all-sky observations were performed from first principles using the TGAS stars in the 8 to 11 magnitude range as reference star catalog. Significant improvements in the astrometric solutions were obtained and the UCAC5 catalog of mean positions at a mean epoch near 2001 was generated. By combining UCAC5 with Gaia DR1 data new proper motions on the Gaia coordinate system for over 107 million stars were obtained with typical accuracies of 1 to 2 mas/yr (R = 11 to 15 mag), and about 5 mas/yr at 16th mag. Proper motions of most TGAS stars are improved over their Gaia data and the precision level of TGAS proper motions is extended to many millions more, fainter stars. External comparisons were made using stellar cluster fields and extragalactic sources. The TGAS data allow us to derive the limiting precision of the UCAC x,y data, which is significantly better than 1/100 pixel. A mirror of UCAC5 exists in the MAST holdings and is thus available as a cone search. All available catalogs are listed at http://archive.stsci.edu/vo/mast_services.html.
588. Fifth VLBA calibrator survey: VCS5
ID:
ivo://CDS.VizieR/J/AJ/133/1236
Title:
Fifth VLBA calibrator survey: VCS5
Short Name:
J/AJ/133/1236
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents the fifth part of the Very Long Baseline Array (VLBA) Calibrator Survey (VCS), containing 569 sources not observed previously with very long baseline interferometry in geodetic or absolute astrometry programs. This campaign has two goals: (1) to observe additional sources that, together with previous survey results, form a complete sample, and (2) to find new strong sources suitable as phase calibrators. This VCS extension was based on three 24-hr VLBA observing sessions in 2005. It detected almost all extragalactic flat-spectrum sources with correlated flux density greater than 200mJy at 8.6GHz above declination -30{deg} that were not observed previously. Source positions with milliarcsecond accuracy were derived from astrometric analysis of ionosphere-free combinations of group delays determined from the 2.3 and 8.6GHz frequency bands. The VCS5 catalog of source positions, plots of correlated flux density versus projected baseline length, contour plots, and FITS files of naturally weighted CLEAN images, as well as calibrated visibility function files, are available on the World Wide Web at http://vlbi.gsfc.nasa.gov/vcs5
589. Filling in the gaps in the 4.85GHz sky
ID:
ivo://CDS.VizieR/J/AJ/138/1032
Title:
Filling in the gaps in the 4.85GHz sky
Short Name:
J/AJ/138/1032
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe a 4.85GHz survey of bright, flat-spectrum radio sources conducted with the Effelsberg 100m telescope in an attempt to improve the completeness of existing surveys, such as CRATES. We report the results of these observations and of follow-up 8.4GHz observations with the VLA of a subset of the sample. We comment on the connection to the Wilkinson Microwave Anisotropy Probe point source catalog and on the survey's effectiveness at supplementing the CRATES sky coverage.
590. Final analysis of ELAIS 15-{mu}m
ID:
ivo://CDS.VizieR/J/MNRAS/358/397
Title:
Final analysis of ELAIS 15-{mu}m
Short Name:
J/MNRAS/358/397
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the final analysis of the European Large Area Infrared Space Observatory (ISO) Survey (ELAIS) 15-{mu}m observations, carried out with the ISO Camera (ISOCAM) instrument on board the ISO. The data-reduction method, known as the Lari Method, is based on a mathematical model of the behaviour of the detector and was specifically designed for the detection of faint sources in ISOCAM/ISO Photopolarimeter (ISOPHOT) data. The method is fully interactive and leads to very reliable and complete source lists. The resulting catalogue includes 1923 sources detected with signal-to-noise ratio of >5 in the 0.5-100mJy flux range and over an area of 10.85deg^2^ split into four fields, making it the largest non-serendipitous extragalactic source catalogue obtained to date from the ISO data.

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