Department of Physics, Rikkyo University
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS)(JAXA)
Department of Physics, Rikkyo University
Smithsonian Astrophysical Observatory
European Space Agency
Department of Physical Science, Graduate School of Science, Hiroshima University
CRESST and X-Ray Astrophysics Laboratory, NASA Goddard Space Flight Center
出版者
宇宙航空研究開発機構
出版者（英）
Japan Aerospace Exploration Agency (JAXA)
雑誌名
宇宙航空研究開発機構特別資料:
雑誌名(英)
JAXA Special Publication: The Energetic Cosmos; from Suzaku to ASTRO-H
巻
JAXA-SP-09-008E
ページ
178 - 181
発行年
2010-02-26
会議概要（会議名, 開催地, 会期, 主催者等）（英）
The 3rd Suzaku international Conference "Energetic Cosmos : from Suzaku to ASTRO-H" (June 29-July 2, 2009. Grand Park Otaru Hotel), Otaru, Hokkaido Japan
抄録（英）
We report the long-awaited discovery of non-thermal X-ray emission from classical nova explosions with a target-of-opportunity observation of V2491 Cygni using the Suzaku observatory. Two 20 ks observations were conducted 9 and 29 days after the outburst on 2008 April 11, yielding wide energy range spectra by combining the X-ray Imaging Spectrometer and the Hard X-ray Detector onboard Suzaku. As a result, super-hard continuum emission extending up to 70 keV was detected successfully on day 9, but it was not present on day 29. This is the highest energy at which X-rays have been detected from classical novae. The spectrum is well explained by an extremely flat power-law emission with a photon index of 0.1 attenuated by a heavy extinction. The power-law emission indicates the presence of an accelerated population of electrons with a non-thermal energy distribution. The extremely flat photon index is too hard for standard diffusive shock acceleration, suggesting that other mechanisms such as acceleration by multiple shocks or magnetic reconnections might take place.
内容記述（英）
Meeting sponsors: The University of Tokyo, The Institute of Physical and Chemical Research, The Japan Society for the Promotion of Science
Discovery of non-thermal emission from the classical nova V2491 Cygni
64574064.pdf
(386.61KB)
