Detection of very-high-energy gamma-ray emission from the vicinity of PSR B1706-44 with H.E.S.S

TL;DR

This paper reports the discovery of a new very-high-energy gamma-ray source near PSR B1706-44, with detailed spectral and spatial analysis, suggesting possible associations with the pulsar and supernova remnant.

Contribution

First detection of VHE gamma-ray emission from the vicinity of PSR B1706-44 using H.E.S.S., including source characterization and spectral analysis.

Findings

Discovered a new VHE gamma-ray source HESS J1708-443.

Source is extended with a Gaussian width of 0.29 degrees.

Energy spectrum follows a power law with photon index 2.0.

Abstract

The energetic pulsar PSR B1706-44 and the adjacent supernova remnant (SNR) candidate G 343.1-2.3 were observed by H.E.S.S. during a dedicated observational campaign in 2007. A new source of very-high-energy (VHE; E > 100 GeV) gamma-ray emission, HESS J1708-443, was discovered with its centroid at RA(J2000) = 17h08m10s and Dec(J2000) = -44d21', with a statistical error of 3 arcmin on each axis. The VHE gamma-ray source is significantly more extended than the H.E.S.S. point-spread function, with an intrinsic Gaussian width of 0.29 +/- 0.04 deg. Its energy spectrum can be described by a power law with a photon index Gamma = 2.0 +/- 0.1 (stat) +/- 0.2 (sys). The integral flux measured between 1-10 TeV is ~17% of the Crab Nebula flux in the same energy range. The possible associations with PSR B1706-44 and SNR G343.1-2.3 are discussed.