@inproceedings{oai:jaxa.repo.nii.ac.jp:00005002,
 author = {Hamaguchi, Kenji and Grosso, Nicolas and Kastner, Joel H. and Weintraub, David A. and Richmond, Michael},
 book = {宇宙航空研究開発機構特別資料:, JAXA Special Publication: The Energetic Cosmos; from Suzaku to ASTRO-H},
 month = {Feb},
 note = {The 3rd Suzaku international Conference "Energetic Cosmos : from Suzaku to ASTRO-H" (June 29-July 2, 2009. Grand Park Otaru Hotel), Otaru, Hokkaido Japan, A deeply embedded young stellar object (YSO) in the L1630 dark cloud has been observed undergoing a new strong optical/near-infrared outburst in 2008 August. The star, V1647 Ori, is the same star that underwent an accretion-powered outburst in 2003-2005; during this eruption we recorded, for the first time, a sustained X-ray outburst from a rapidly accreting YSO. The X-ray activity is suspected to be driven by a star-disk magnetic dynamo, accompanied by rapid mass accretion. However, observations that might support or refute this hypothesis have been limited in quantity and quality. We triggered a ToO observation of V1647 Ori with Suzaku for 40 ksec on 2008 October 8 using Director's Discretionary Time. During the observation, V1647 Ori showed a gradual flux decrease by a factor of 5 and then displayed an abrupt flux increase by an order of magnitude. The spectrum clearly displays emission from Helium-like iron, which is a signature of hot plasma (kT approximately 5 keV). Such X-ray properties were also seen in an XMM-Newton observation during the first outburst, but it has rarely been observed for other YSOs. Hence, the new outburst started in 2008 is likely driven by a mechanism similar to that of the first outburst. The Suzaku/XIS spectrum of V1647 Ori also shows a remarkable fluorescent iron K line with an equivalent width of approximately 600 eV. Such a large equivalent width indicates that a part of the incident X-ray emission that irradiates the circumstellar material is hidden from our line of sight., Meeting sponsors: The University of Tokyo, The Institute of Physical and Chemical Research, The Japan Society for the Promotion of Science, 資料番号: AA0064574070, レポート番号: JAXA-SP-09-008E},
 pages = {196--197},
 publisher = {宇宙航空研究開発機構, Japan Aerospace Exploration Agency (JAXA)},
 title = {Suzaku Observation of a New X-ray Outburst from the Accreting Young Star Illuminating McNeil's Nebula},
 volume = {JAXA-SP-09-008E},
 year = {2010}
}