High Galactic latitude Fermi sources of gamma-rays with energies above 100 GeV

TL;DR

This paper presents a catalog of high Galactic latitude gamma-ray sources above 100 GeV detected by Fermi LAT, identifying new sources and analyzing their correlation with known objects like BL Lacertae, expanding our understanding of very high energy gamma-ray emitters.

Contribution

The study provides the first comprehensive catalog of >100 GeV gamma-ray sources at high Galactic latitudes, including new detections and correlation analysis with BL Lac objects.

Findings

Significant correlation between high-energy photons and Fermi sources.

Catalog includes 75 high-confidence sources, mostly BL Lac objects.

Most sources are at redshifts up to z~1, with many being newly reported.

Abstract

We present a catalog of sources of very high energy (E>100 GeV) gamma-rays detected by the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope at Galactic latitudes |b|>=10 degrees. We cross-correlate the directions of individual photons with energies above 100 GeV detected by Fermi/LAT with the first year Fermi catalog of sources detected at lower energies. We find a significant correlation between the arrival directions of the highest energy photons and positions of Fermi sources, with the possibility of chance coincidences at the level of 1e-45. We present a list of Fermi sources contributing to the correlation signal. A similar analysis is performed to cross-correlate the catalog of BL Lac objects with the highest energy photons detected by Fermi. We produce a catalog of high Galactic latitude Fermi sources visible at 100-300 GeV energies. The catalog is divided into two parts. The first part contains a list of 50 higher significance sources among which there can be three possible false detections. The second part of the catalog contains a list of 25 lower significance sources, among which six are possibly false detections. Finally we identify eight additional sources from the cross-correlation analysis with the BL Lac catalog. The reported sources of E>100 GeV gamma-rays span a broad range of redshifts, up to z~1. Most of the sources are BL Lac type objects. Only 17 out of 83 objects in our list were previously reported as VHE gamma-ray sources.