Troja 2007 GRB070110的观测

主要内容:
有极亮的X射线余辉

精彩摘抄:


文章信息:

astro-ph/0702220 [abs, ps, pdf, other] :

Title: Swift observations of GRB 070110: an extraordinary X-ray afterglow powered by the central engine
Authors: E. Troja, G. Cusumano, P. O'Brien, B. Zhang, B. Sbarufatti, V. Mangano, R. Willingale, G. Chincarini, J. P. Osborne, F. E. Marshall, D. N. Burrows, S. Campana, N. Gehrels, C. Guidorzi, H. A. Krimm, V. La Parola, E. W. Liang, T. Mineo, A. Moretti, K. L. Page, P. Romano, G. Tagliaferri, B. B. Zhang
Comments: 10 pages, 5 figures, submitted to ApJ

We present a detailed analysis of Swift multi-wavelength observations of GRB 070110 and its remarkable afterglow. The early X-ray light curve, interpreted as the tail of the prompt emission, displays a spectral evolution already seen in other gamma-ray bursts. The optical afterglow shows a shallow decay up to ~2 d after the burst, which is not consistent with standard afterglow models. The most intriguing feature is a very steep decay in the X-ray flux at ~20 ks after the burst, ending an apparent plateau. The abrupt drop of the X-ray light curve rules out an external shock as the origin of the plateau in this burst and implies long-lasting activity of the central engine. The temporal and spectral properties of the plateau phase point towards a continuous central engine emission rather than the episodic emission of X-ray flares. We suggest that the observed X-ray plateau is powered by a spinning down central engine, possibly a millisecond pulsar, which dissipates energy at an internal radius before depositing energy into the external shock.