Studies of EGRET sources with a novel image restoration technique

TL;DR

This paper introduces a new image restoration method tailored for gamma-ray telescope data, improving source identification by accounting for variable PSF and noise reduction.

Contribution

The paper presents a novel image restoration algorithm that incorporates event-specific PSF and wavelet filtering, enhancing gamma-ray source analysis.

Findings

Effective in identifying extended gamma-ray sources

Handles PSF variability across energies and angles

Reduces noise in low photon count images

Abstract

We have developed an image restoration technique based on the Richardson-Lucy algorithm optimized for GLAST-LAT image analysis. Our algorithm is original since it utilizes the PSF (point spread function) that is calculated for each event. This is critical for EGRET and GLAST-LAT image analysis since the PSF depends on the energy and angle of incident gamma-rays and varies by more than one order of magnitude. EGRET and GLAST-LAT image analysis also faces Poisson noise due to low photon statistics. Our technique incorporates wavelet filtering to minimize noise effects. We present studies of EGRET sources using this novel image restoration technique for possible identification of extended gamma-ray sources.