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arXiv 1011.4489astro-ph.HE
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关于LS I +61 303相关X射线/VHE发射的起源

On the origin of correlated X-ray/VHE emission from LS I +61 303

V. Zabalza, J. M. Paredes, V. Bosch-Ramon

摘要:

MAGIC合作最近报道了伽马射线双星LS I +61 303在一个轨道的60%期间的相关X射线和非常高能量的伽马射线发射。这些观测结果表明,这两个波段的发射起源于单个粒子群。我们的目标是提高我们的理解,通过解释同时X射线和VHE数据通过辐射模型的源行为。我们使用的模型的基础上的一个区域人口的相对论轻子粒子假设占主导地位的绝热损失位于紧凑的对象的位置。从X射线通量推断绝热冷却时间尺度。该模型可以再现X射线和VHE波段的光谱和光变曲线。绝热损失可能是解释X射线和部分VHE光变曲线的关键因素。从最佳拟合结果中,我们得到了B=0.2 G的磁场,最小亮度预算约为2 × 10^35 erg/s,以及相对较高的加速效率。此外,我们的研究结果似乎证实,费米探测到的GeV发射并不来自相同的父粒子的X射线和VHE发射和费米谱的硬度粒子谱在较低的能量构成了约束。在我们的场景中,更敏感的观测将允许限制倾斜角,这可以确定紧凑物体的性质。

英文摘要:

The MAGIC collaboration has recently reported correlated X-ray and very high-energy gamma-ray emission from the gamma-ray binary LS I +61 303 during ~60% of one orbit. These observations suggest that the emission in these two bands has its origin in a single particle population. We aim at improving our understanding of the source behaviour by explaining the simultaneous X-ray and VHE data through a radiation model. We use a model based on a one zone population of relativistic leptonic particles assuming dominant adiabatic losses located at the position of the compact object. The adiabatic cooling timescale is inferred from the X-ray fluxes. The model can reproduce the spectra and lightcurves in the X-ray and VHE bands. Adiabatic losses could be the key ingredient to explain the X-ray and partially the VHE lightcurves. From the best fit result, we obtain a magnetic field of B=0.2 G, a minimum luminosity budget of ~2x10^35 erg/s and a relatively high acceleration efficiency. In addition, our results seem to confirm that the GeV emission detected by Fermi does not come from the same parent particle population as the X-ray and VHE emission and the Fermi spectrum poses a constraint on the hardness of the particle spectrum at lower energies. In the context of our scenario, more sensitive observations would allow to constrain the inclination angle, which could determine the nature of the compact object.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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