VERITAS Observations of a "Forbidden Velocity Wing"

TL;DR

This paper reports VERITAS observations of a forbidden velocity wing associated with a supernova remnant, revealing TeV gamma-ray emission that suggests long-lasting particle acceleration in such remnants.

Contribution

It presents the first detection of TeV gamma-ray emission from a forbidden velocity wing linked to a supernova remnant, indicating prolonged particle acceleration.

Findings

Detection of TeV gamma-ray emission from FVW 190.2+1.1

Shell-like morphology observed in HI maps

Implication of long-term particle acceleration in supernova remnants

Abstract

The H.E.S.S. extended Galactic plane survey revealed the presence of a new extended TeV gamma-ray source, HESSJ1503-582, with no obvious counterpart at other wavelengths. The source is, however, coincident with an HI structure with a velocity significantly different from that of galactic rotation - a so-called "Forbidden Velocity Wing". These structures have been suggested as the fast moving shells and filaments associated with the oldest supernova remnants in our galaxy. The detection of TeV gamma-ray emission from these structures might indicate that supernova remnants remain efficient particle accelerators for much longer than is commonly believed. Here we report on recent VERITAS observations of one of these structures, FVW 190.2+1.1, which shows a clear shell-like morphology in the HI maps.