Multiple flaring activity in the supergiant fast X‐ray transient IGR J08408−4503 observed with Swift
Multiple flaring activity in the supergiant fast X‐ray transient IGR J08408−4503 observed with Swift
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用 Swift 观测到的超巨快速 X 射线瞬变 IGR J08408−4503 中的多次耀斑活动
DOI：
10.1111/j.1365-2966.2008.14050.x
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发表时间：
2008
影响因子：
4.8
通讯作者：
V. Mangano
中科院分区：
文献类型：
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作者：
P. Romano;L. Sidoli;G. Cusumano;P. Evans;L. Ducci;H. Krimm;H. Krimm;S. Vercellone;K. Page;A. Beardmore;D. Burrows;J. Kennea;N. Gehrels;V. Parola;V. Mangano
IGRJ08408-4503是2006年发现的一颗超巨星，它被证实与08.5Ib(F)超巨星HD 74194有关。我们报告了2006年10月4日和2008年7月5日SWIFT/Burst警报望远镜(BAT)捕捉到的两次爆发的分析，并用SWIFT/X射线望远镜(XRT)在较软的能量下进行了跟踪。2008年的XRT光曲线显示了一个多峰结构，最初的明亮耀斑达到了∼10-9erg cm-2 S-1(2-10keV)的通量，随后在75k内出现了两个相同亮度的耀斑。耀斑的光谱特征差异很大，通过时间分辨光谱分析得出的大部分差异是由于吸收柱的变化造成的。我们观察到，随着时间的推移，用吸收的幂定律模型拟合得到的N H逐渐减小。我们解释这些N-H变化是由于第一次耀斑产生的电离效应，导致测量到的向源的列密度显著降低。耀斑的持续时间以及爆发的时间表明，如果在Sidoli等人的框架内解释耀斑活动，则轨道周期为∼35d。中子星在相对于轨道平面倾斜的赤道风中通过而触发爆发的模型。
IGR J08408-4503 is a supergiant fast X-ray transient discovered in 2006 with a confirmed association with a 08.5Ib(f) supergiant star, HD 74194. We report on the analysis of two outbursts caught by Swift/Burst Alert Telescope (BAT) on 2006 October 4 and 2008 July 5, and followed up at softer energies with Swift/X-ray Telescope (XRT). The 2008 XRT light curve shows a multiple-peaked structure with an initial bright flare that reached a flux of ∼10 -9 erg cm -2 s -1 (2-10 keV), followed by two equally bright flares within 75 ks. The spectral characteristics of the flares differ dramatically, with most of the difference, as derived via time-resolved spectroscopy, being due to absorbing column variations. We observe a gradual decrease in the N H , derived with a fit using absorbed power-law model, as time passes. We interpret these N H variations as due to an ionization effect produced by the first flare, resulting in a significant decrease in the measured column density towards the source. The durations of the flares as well as the times of the outbursts suggest that the orbital period is ∼35 d, if the flaring activity is interpreted within the framework of the Sidoli et al. model with the outbursts triggered by the neutron star passage inside an equatorial wind inclined with respect to the orbital plane.
与 ASCA 在盾片臂区域发现瞬态 X 射线脉冲星 AX J1841.0-0536
DOI：
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发表时间：
2001
期刊：
Publications of the Astronomical Society of Japan 53
影响因子：
--
作者：
Aya Bamba;Jun Yokogawa;Masaru Ueno;Katsuji Koyama;Shigeo Yamauchi
通讯作者：
Shigeo Yamauchi