تقرير
VLBI Observation of Microquasar Cyg X-3 during an X-ray State Transition from Soft to Hard in the 2007 May-June Flare
| العنوان: | VLBI Observation of Microquasar Cyg X-3 during an X-ray State Transition from Soft to Hard in the 2007 May-June Flare |
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| المؤلفون: | Kim, Jeong-Sook, Kim, Soon-Wook, Kurayama, Tomoharu, Honma, Mareki, Sasao, Tetsuo, Kim, Sang Joon |
| المصدر: | ApJ 772, July 20 issue (2013) |
| سنة النشر: | 2013 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - High Energy Astrophysical Phenomena |
| الوصف: | We present a radio observation of microquasar Cyg X-3 during an X-ray state transition from ultrasoft to hard state in the 2007 May$-$June flare using the VLBI Exploration of Radio Astrometry (VERA) at 22 GHz. During the transition, a short-lived mini-flare of ${\lesssim}3$ hr was detected prior to the major flare. In such a transition, a jet ejection is believed to occur, but there have been no direct observations to support it. An analysis of Gaussian fits to the observed visibility amplitudes shows a time variation of the source axis, or a structural change, during the mini-flare. Our model fits, together with other multiwavelength observations in the radio, soft, and hard X-rays, and the shock-in-jet models for other flaring activities at GHz wavebands, suggest a high possibility of synchrotron flares during the mini-flare, indicative of a predominant contribution from jet activity. Therefore, the mini-flare with an associated structural change is indicative of a jet ejection event in the state transition from ultrasoft to hard state. Comment: 12 pages, 3 figures, accepted for publication in ApJ |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1088/0004-637X/772/1/41 |
| URL الوصول: | http://arxiv.org/abs/1307.1226 |
| رقم الأكسشن: | edsarx.1307.1226 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1088/0004-637X/772/1/41 |
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