Application of the MST clustering to the high energy gamma-ray sky. II - Possible detection of gamma-ray emission from blazar candidates in the 1WHSP sample

TL;DR

This study uses the MST clustering algorithm on 7-year Fermi-LAT gamma-ray data above 10 GeV to identify potential gamma-ray sources near infrared-selected blazar candidates, revealing 16 photon clusters linked to new or candidate blazars.

Contribution

First application of MST clustering to high-energy gamma-ray data to identify potential blazar sources near infrared-selected candidates.

Findings

Identified 16 photon clusters near blazar candidates

Detected potential gamma-ray emission from new or candidate blazars

Provided properties of the clusters and associated sources

Abstract

We present the results of a photon cluster search in the 7-years Fermi-Large Area Telescope extragalactic Pass 8 gamma-ray sky by means of the Minimum Spanning Tree (MST) algorithm, at energies higher than 10 GeV. We found 16 clusters of photons, corresponding to candidate gamma-ray sources, located very close to infrared-selected sources in the 1WHSP (WISE High Synchrotron Peaked) sample, and therein classified as either "new" or "candidate" blazars. In this paper some properties of the MST clusters and of the associated sources are presented.