CANGAROO-III Search for Gamma Rays from SN 1987A and the Surrounding Field

TL;DR

This paper reports on CANGAROO-III observations of SN 1987A and nearby objects, setting upper limits on TeV gamma-ray fluxes, and compares these limits with theoretical predictions to understand particle acceleration in the supernova environment.

Contribution

First observational upper limits on TeV gamma-ray emission from SN 1987A and surrounding objects using CANGAROO-III, constraining models of particle acceleration.

Findings

No significant TeV gamma-ray detection from SN 1987A.

Upper limits on gamma-ray fluxes for SN 1987A and nearby objects.

Comparison with theoretical models constrains particle acceleration scenarios.

Abstract

Optical images of SN 1987A show a triple ring structure. The inner (dust) ring has recently increased in brightness and in the number of hot spots suggesting that the supernova shock wave has collided with the dense pre-existing circumstellar medium, a scenario supported by radio and X-ray observations. Such a shocked environment is widely expected to result in the acceleration of charged particles, and the accompanying emission of very high energy gamma-rays. Here, we report the results of observations made in 2004 and 2006 which yield upper limits on the TeV gamma-ray flux, which are compared with a theoretical prediction. In addition, we set upper limits on the TeV flux for four high energy objects which are located within the same field of view of the observation: the super-bubble 30 Dor C, the Crab-like pulsar PSR B0540$-$69, the X-ray binary LMC X-1, and the supernova remnant N157B.