Evidence for TeV Gamma-Ray Emission from a Region of the Galactic Plane

Journal Article · Fri Dec 16 04:00:00 EST 2005 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.95.251103· OSTI ID:20699692

Atkins, R; Gonzalez, M M; McEnery, J E; Wilson, M E ^[1]; Benbow, W; Coyne, D G; Dorfan, D E; Kelley, L A; Morales, M F; Parkinson, P.M. Saz; Williams, D A ^[2]; Berley, D; Blaufuss, E; DeYoung, T; Goodman, J A; Hays, E; Lansdell, C P; Noyes, D; Smith, A J; Sullivan, G W ^[3]

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1. Department of Physics, University of Wisconsin, 1150 University Avenue, Madison, Wisconsin 53706 (United States)
2. Santa Cruz Institute for Particle Physics, University of California, 1156 High Street, Santa Cruz, California 95064 (United States)
3. Department of Physics, University of Maryland, College Park, Maryland 20742 (United States); and others

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 (set-membership sign) (40 deg.,100 deg.) and latitude vertical bar b vertical bar <5 deg. Under the assumption of a simple power law spectrum, with no cutoff in the EGRET-Milagro energy range, the measured integral flux is {phi}{sub {gamma}}(>3.5 TeV)=(6.4{+-}1.4{+-}2.1)x10{sup -11} cm{sup -2} s{sup -1} sr{sup -1}. This flux is consistent with an extrapolation of the EGRET spectrum between 1 and 30 GeV in this galactic region.

• OSTI ID: 20699692
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 25 Vol. 95; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CHERENKOV COUNTERS
EXTENSIVE AIR SHOWERS
EXTRAPOLATION
GALAXIES
GAMMA ASTRONOMY
GAMMA RADIATION
GEV RANGE 01-10
GEV RANGE 10-100
PHOTON EMISSION
TEV RANGE 01-10