Suzaku observations of the galaxy cluster 1RXS J0603.3+4214: Implications of particle acceleration processes in the "Toothbrush" radio relic
Suzaku observations of the galaxy cluster 1RXS J0603.3+4214: Implications of particle acceleration processes in the "Toothbrush" radio relic
复制标题
朱雀对星系团 1RXS J0603.3 4214 的观测：“牙刷”无线电遗迹中粒子加速过程的影响
DOI：
10.1093/pasj/psv084
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发表时间：
2015
影响因子：
2.3
通讯作者：
Reinout J. van Weeren
中科院分区：
文献类型：
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作者：
Madoka Itahana;Motokazu Takizawa;Hiroki Akamatsu;Takaya Ohashi;Yoshitaka Ishisaki;Hajime Kawahara;Reinout J. van Weeren
我们介绍了用“牙刷”射电遗迹对星系团1RXS J0603.3+4214的朱雀观测结果。从射电观测结果来看，遗迹外缘可能出现马赫数为m≃4的激波，但对星系团内介质的温度测量表明，其温度差异小于预期。在考虑统计误差和系统误差的情况下，遗迹外缘温差估计的马赫数明显低于无线电数据估计的马赫数。这表明，通常用于将无线电频谱指数与马赫数联系起来的线性测试粒子体系中的扩散冲击加速度理论对这一遗迹无效。通过XMM-Newton数据的x射线表面亮度分析，我们还测量了遗址西部的温度差异，发现该区域存在m≃1.6的激波，并独立得出了一致的结果。我们在遗迹区寻找非热逆Compton分量，得到0.3-10 keV波段的通量上限为2.4 × 10−13erg cm−2s−1。磁场强度的下限为1.6 μG，这意味着磁能密度可以超过热能的几个百分点。
We present the results of Suzaku observations of the galaxy cluster 1RXS J0603.3+4214 with the “Toothbrush” radio relic. Although a shock with Mach numberM≃ 4 is expected at the outer edge of the relic from the radio observation, our temperature measurements of the intracluster medium indicate a weaker temperature difference than expected. The Mach number estimated from the temperature difference at the outer edge of the relic isM≃ 1.5, which is significantly lower than the value estimated from the radio data even considering both statistical and systematic errors. This suggests that a diffusive shock acceleration theory in the linear test particle regime, which is commonly used to link the radio spectral index to the Mach number, is invalid for this relic. We also measured the temperature difference across the western part of the relic, where a shock withM≃ 1.6 is suggested from the X-ray surface brightness analysis of the XMM-Newton data, and obtained consistent results in an independent way. We searched for the non-thermal inverse Compton component in the relic region and the resultant upper limit on the flux is 2.4 × 10−13erg cm−2s−1in the 0.3–10 keV band. The lower limit of the magnetic field strength becomes 1.6 μG, which means that magnetic energy density could be more than a few percent of the thermal energy.