Constraining the extension of a possible gamma-ray halo of 3C 279 from 2008-2014 solar occultations

TL;DR

This study analyzes seven solar occultations of 3C 279 observed by Fermi-LAT from 2008 to 2014 to constrain the possible size and flux of a gamma-ray halo around the source.

Contribution

It provides the first constraints on the size and flux of a gamma-ray halo around 3C 279 based on occultation data.

Findings

Constraints on the size of the gamma-ray halo

Limits on the flux of the gamma-ray halo

Methodology for using solar occultations to study gamma-ray halos

Abstract

The angular extension of the gamma-ray image of 3C 279 may be constrained by studying its solar occultations as suggested by Fairbairn et al. (2010). We perform this kind of analysis for seven occultations observed by Fermi-LAT in 2008-2014, using the Fermi-LAT Solar System tools. The results are interpreted in terms of models with extended gamma-ray halo of 3C 279; first constraints on the size and the flux of the halo are reported.