Integral and rxte observations of accreting millisecond pulsar igr j00291+5934 in outburst
Integral and rxte observations of accreting millisecond pulsar igr j00291+5934 in outburst
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DOI：
10.1051/0004-6361:20053472
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发表时间：
2005-08
影响因子：
6.5
通讯作者：
M. Falanga;L. Kuiper;J. Poutanen;E. Bonning;W. Hermsen;T. Salvo;P. Goldoni;A. Goldwurm;S. Shaw;L. Stella
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文献类型：
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作者：
M. Falanga;L. Kuiper;J. Poutanen;E. Bonning;W. Hermsen;T. Salvo;P. Goldoni;A. Goldwurm;S. Shaw;L. Stella
分析了国际伽玛射线天体物理实验室和Rossi X射线Timins探测器在2004年12月爆发期间对吸积动力毫秒脉冲星IGR J 00291 +5934的同时观测。平均光谱是很好地描述了热康普顿与电子温度为50 keV和汤姆逊光学深度τ T <$1在一个平板几何。在爆发过程中，光谱形状几乎是恒定的。我们首次观测到一颗吸积毫秒脉冲星的上旋，其速度为ν = 8.4 × 10 - 13 Hz s-1。ISGRI数据揭示了高达-150keV的X射线脉动周期为1.67毫秒。脉冲分数示出增加6%铝6千电子伏至12- 20%，在100千电子伏。这是很自然地解释了多普勒效应对指数截止康普顿谱从热点的作用。近正弦脉冲显示软滞后与复杂的能量依赖性，增加到7千电子伏，然后减少到15千电子伏，似乎在更高的能量饱和。
Simultaneous observations of the accretion-powered millisecond pulsar IGR J00291+5934 by the International Gamma-Ray Astrophysics Laboratory and Rossi X-ray Timins Explorer during the 2004 December outburst are analysed. The average spectrum is well described by thermal Comptonization with an electron temperature of 50 keV and Thomson optical depth τ T ∼ 1 in a slab geometry. The spectra] shape is almost constant during the outburst. For the first time we detect a spin-up, ν = 8.4 x 10 -13 Hz s -1 , of an accreting millisecond pulsar. The ISGRI data reveal the pulsation of X-rays at a period of 1.67 milliseconds up to -150 keV. The pulsed fraction is shown to increase from 6 per cent al 6 keV to 12-20 per cent at 100 keV. This is naturally explained by the action of the Doppler effect on the exponentially cutoff Comptonization spectrum from the hot spot. The nearly sinusoidal pulses show soft lags with a complex energy dependence, increasing up to 7 keV, then decreasing to 15 keV, and seemingly saturating at higher energies.