Early Pulsar Observations and GLAST LAT Performance

Journal Article · Thu Jul 12 00:00:00 EDT 2007 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2757384· OSTI ID:21067268

Reposeur, T; Dumora, D; Guillemot, L; Lemoine-Goumard, M; Parent, D; Smith, D ^[1]

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1. CENBG. Universite Bordeaux 1-CNRS-IN2P3, Chemin du Solarium, 33175 Gradignan (France)

Vela is the brightest pulsar known in the GeV gamma ray range, yielding a clear signal in less than a day of observations with the Large Area Telescope (LAT). The striking pulsed signature provides a rich opportunity to compare the real gamma ray response of the GLAST LAT to expectations from the highly-detailed Monte Carlo detector simulations. This is critical because all flux and spectral measurements with the LAT rely on the acceptances parametrized by the Instrument Response Functions (IRF), extracted from the simulations. We successively apply the analysis cuts used to identify gamma rays and to reject background, comparing at each step the observed and predicted yields. This procedure is repeated for gamma rays incident on different parts of the LAT and at different angles. Incidence angles will vary widely during normal observations in sky survey mode, and a 2-week pointed mode observation during the Launch and Early Operations phase (L and EO) favors yet a different part of phase space. This method is expected to yield Monte Carlo validations complementary to those already obtained at CERN and at other particle accelerators.

• OSTI ID: 21067268
• Journal Information: AIP Conference Proceedings, Vol. 921, Issue 1; Conference: 1. GLAST symposium, Stanford, CA (United States), 5-8 Feb 2007; Other Information: DOI: 10.1063/1.2757384; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA). GLAST LAT Collaboration; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
COSMIC GAMMA SOURCES
COSMIC PHOTONS
GAMMA ASTRONOMY
GAMMA DETECTION
GAMMA RADIATION
GAMMA SPECTRA
GEV RANGE
INCIDENCE ANGLE
MONTE CARLO METHOD
PERFORMANCE
PHASE SPACE
PHOTON EMISSION
PULSARS
RESPONSE FUNCTIONS
TELESCOPE COUNTERS