Catalog Service: Fermi LAT Long-Term Transient Source Catalog
Description
The First Catalog of Long-Term Transient Sources detected by Fermi Large Area Telescope (LAT) comprises of 142 unique, transient sources that were detected on monthly time intervals during Fermi-LAT operations. The monthly time scale allows to identify transient and variable sources that were not yet reported in other Fermi-LAT catalogs. The monthly datasets were analyzed using a wavelet-based source detection algorithm that provided the candidate new transient sources. The search was limited to the extragalactic regions of the sky to avoid the dominance of the Galactic diffuse emission at low Galactic latitudes. The transient candidates were then analyzed using the standard Fermi-LAT maximum likelihood analysis method. All sources detected with a statistical significance above 4 sigma in at least one monthly bin were listed in the final catalog. This database table was ingested by the HEASARC in September 2021 and is based upon file downloaded from the Space Science Data Center (SSDC) Fermi-1FLT <a href="https://www.ssdc.asi.it/fermi1flt/">website</a>. This is a service provided by NASA HEASARC .
This section describes who is responsible for this resource
Publisher: NASA/GSFC HEASARCivo://nasa.heasarc/ASD[Pub. ID]
Contact Information:
This section provides some status information: the resource version, availability, and relevant dates.
This resource was registered on: 2025 Mar 07 00:00:00ZThis resource description was last updated on: 2025 Mar 07 00:00:00Z
This section describes what the resource is, what it contains, and how it might be relevant.
Related Resources:
This section describes the data's coverage over the sky, frequency, and time.
Reference Coordinate System: UTC-ICRS-TOPOXXivo://STClib/CoordSys#UTC-ICRS-TOPO[Res. ID]
Sky Coverage: Regions covered:
Wavebands covered:
This is a standard IVOA service that takes as input a position in the sky and a radius and returns catalog records with positions within that radius.
VERB=1
VERB=3
This is a standard IVOA service that takes as input an ADQL or PQL query and returns tabular data.
This is service that does not comply with any IVOA standard but instead provides access to special capabilities specific to this resource.
Developed with the support of the National Science Foundation under Cooperative Agreement AST0122449 with the Johns Hopkins University The NAVO project is a member of the International Virtual Observatory Alliance
This NAVO Application is hosted by the Space Telescope Science Institute