Gamma-ray emission from a narrow band at the galactic equator has previously been detected up to 30 GeV. We report evidence for a TeV gamma-ray signal from a region of the galactic plane by Milagro, a large-field-of-view water Cherenkov detector for extensive air showers. An excess with a significance of 4.5 standard deviations has been observed from the region of galactic longitude l (40°,100°) and latitude |b|<5°. Under the assumption of a simple power law spectrum, with no cutoff in the EGRET-Milagro energy range, the measured integral flux is γ(>3.5TeV)=(6.4±1. 4±2.1)×10-11cm-2s-1sr-1. This flux is consistent with an extrapolation of the EGRET spectrum between 1 and 30 GeV in this galactic region.
ASJC Scopus subject areas
- Physics and Astronomy(all)