MODELING HIGH-ENERGY LIGHT CURVES OF THE PSR B1259−63/LS 2883 BINARY BASED ON 3D SPH SIMULATIONS
MODELING HIGH-ENERGY LIGHT CURVES OF THE PSR B1259−63/LS 2883 BINARY BASED ON 3D SPH SIMULATIONS
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DOI：
10.1088/0004-637x/750/1/70
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发表时间：
2012-03
期刊：
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通讯作者：
J. Takata;A. Okazaki;S. Nagataki;T. Naito;A. Kawachi;S. Lee;M. Mori;K. Hayasaki;M. Yamaguchi;S. Owocki
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文献类型：
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作者：
J. Takata;A. Okazaki;S. Nagataki;T. Naito;A. Kawachi;S. Lee;M. Mori;K. Hayasaki;M. Yamaguchi;S. Owocki
基于脉冲星与Be盘和风相互作用的三维光滑粒子流体力学模拟，研究了脉冲星B1259−63/LS2883脉冲星双星从X射线到超高能伽马射线辐射的时间变化。利用模拟的脉冲星风激波几何和压强分布，计算了双星的近地星子通道，并计算了同步辐射和逆康普顿辐射的变化。在密度较高的Be盘条件下(基密度∼10−9g cm−3)，我们的模拟再现了观测得到的特征双峰X射线光曲线。我们解释说，近星前后的峰值分别是由于脉冲星在近星通过前穿过盘时轨道相从脉冲星自旋向下的能量到激波加速粒子能量的转换效率显著增加，以及当脉冲星风在近星通过后在盘状气体中产生空洞时。反之，在同样呈现双峰特征的模型TeV光曲线中，第一个峰值出现在近星相位附近。简要讨论了冷却过程对TeV光曲线的可能影响。
Temporal changes of X-ray to very high energy gamma-ray emissions from the pulsar–Be-star binary PSR B1259−63/LS 2883 are studied based on three-dimensional smoothed particle hydrodynamic simulations of pulsar wind interaction with Be-disk and wind. We focus on the periastron passage of the binary and calculate the variation of the synchrotron and inverse-Compton emissions using the simulated shock geometry and pressure distribution of the pulsar wind. The characteristic double-peaked X-ray light curve from observations is reproduced by our simulation under a dense Be-disk condition (base density ∼10−9 g cm−3). We interpret the pre- and post-periastron peaks as being due to a significant increase in the conversion efficiency from pulsar spin-down power to the shock-accelerated particle energy at orbital phases when the pulsar crosses the disk before periastron passage, and when the pulsar wind creates a cavity in the disk gas after periastron passage, respectively. On the contrary, in the model TeV light curve, which also shows a double-peak feature, the first peak appears around the periastron phase. The possible effects of cooling processes on the TeV light curve are briefly discussed.