Energy spectrum of TeV gamma rays from Mrk 501 obtained by stereoscopic analysis

Authors
Yamamoto, T Chamoto, N Chikawa, M Hayashi, S Hayashi, Y Hayashida, N Hibino, K Hirasawa, H Honda, K Hotta, N Inoue, N Ishikawa, F Ito, N Kabe, S Kajino, F Kashiwagi, T Kawakami, S Kawasaki, Y Kawasumi, N Kitamura, H Kuramochi, K Kusano, E Lafoux, H Loh, EC Matsuyama, T Mizutani, K Nagano, M Nishikawa, D Nishimura, J Nishiyama, T Nishizawa, M Ouchi, T Ohoka, H Ohnishi, M Saito, T Sakaki, N Sakata, M Sasano, M Shimodaira, H Shiomi, A Sokolsky, P Takahashi, T Taylor, SF Takeda, M Teshima, M Torii, R Tsukiji, M Uchihori, Y Yamamoto, Y Yoshida, S Yoshii, H Yuda, T
Citation
T. Yamamoto et al., Energy spectrum of TeV gamma rays from Mrk 501 obtained by stereoscopic analysis, ASTROPART P, 11(1-2), 1999, pp. 141-144
Citations number
7
Categorie Soggetti
Space Sciences
Journal title
ASTROPARTICLE PHYSICS
ISSN journal
09276505 → ACNP
Volume
11
Issue
1-2
Year of publication
1999
Pages
141 - 144
Database
ISI
SICI code
0927-6505(199906)11:1-2<141:ESOTGR>2.0.ZU;2-P
Abstract
We have observed flares of TeV-gamma rays from Mrk501 in 1997 using three t elescopes of the Utah Seven Telescope Array at Dugway, Utah. Determination of the energy spectrum from such Active Galactic Nuclei (AGN) is very impor tant, because the gamma-ray spectrum is expected to steepen around 10 TeV f rom objects like Mrk501 by the interaction of the infrared photons. We have developed the method to estimate energies of the gamma rays by stereoscopi c analysis using multiple telescopes. The differential index of the energy spectrum obtained is well expressed by -2.5 between 700 GeV and 3 TeV. This spectrum seems to become steeper above several TeV. (C) 1999 Elsevier Scie nce B.V. All rights reserved.