The Whipple Observatory's discovery of extragalactic TeV photons from Markarian 421 in 1992 marked the beginning of extragalactic gamma-ray astronomy at very high-energy (VHE, E > 100 GeV).
Three decades later, both the number of detected extragalactic VHE sources and the variety of their observed spectral states have greatly increased.
We present a catalog that summarizes the main spectral analysis results from extragalactic observations made by imaging atmospheric Cherenkov telescopes (IACTs).
The Spectral TeV Extragalactic Catalog, STeVECat, is a collection of 403 very-high energy spectra with at least two data points published in journals between 1992 and 2021. In addition to spectral points and associated physical units, the catalog features observational metadata in the form of observation periods, livetime, excess counts over background and significance when available.
STeVECat also includes the coordinates and types of the observed sources, as well as their redshifts whenever available from dedicated spectroscopic studies.
This work enables studies using TeV photons that require a large corpus of extragalactic VHE observations, such as population studies of extragalactic VHE sources, studies of the GeV-TeV connection and studies of the optical to infrared content of the universe.
As the most extensive collection of extragalactic IACT observations so far, STeVECat allows a comprehensive view of the currently known extragalactic sky before the advent of the new generation of IACT, the Cherenkov Telescope Array (CTA).
The catalog will be made public and made accessible through the catalog subpackage of Gammapy, the Science Analysis Tool selected by the CTA Observatory.