The diffuse, relic radio source in Abell 85: estimation of cluster-scale magnetic field from inverse Compton X-rays
The diffuse, relic radio source in Abell 85: estimation of cluster-scale magnetic field from inverse Compton X-rays
复制标题
DOI：
10.1046/j.1365-8711.1998.01589.x
复制
发表时间：
1998-03
影响因子：
4.8
通讯作者：
J. Bagchi;V. Pislar;G. L. Neto
中科院分区：
文献类型：
--
作者：
J. Bagchi;V. Pislar;G. L. Neto
我们报告的逆康普顿X射线发射的第一次检测，空间相关的一个非常陡峭的频谱无线电源（VSSRS），0038-096，没有任何检测到的光学对应物，在集群阿贝尔85。ROSAT PSPC数据及其多尺度小波分析揭示了一个大尺度（线性直径约为500 h^{-1}_{50} kpc）的弥散X射线分量，超过了热韧致辐射，与同样大尺度的VSSRS重叠。原始的3 K背景光子，从相对论电子散射出来，可以产生探测到的X射线。在0.5-2.4 keV的X射线波段，反康普顿通量估计为（6.5pm 0.5）10^{-13} erg s^{-1}cm^{-2}。一个新的327兆赫无线电地图的集群领域。在10-100 MHz无线电波段，同步辐射通量估计为（6.6pm 0.90）× 10^{-14} erg s^{-1} cm^{-2}。从相对论电子的共同系综中探测到无线电和X射线发射的积极结果导致了星团尺度磁场强度的估计为（0.95\pm 0.10）10^{-6} G。估计的领域是免费的'均分'猜想，距离和排放量。此外，辐射通量和估计的磁场意味着存在“遗迹”（辐射寿命> 10^{9}年）相对论电子，洛伦兹因子\gamma \约为700-1700，这将是迄今未探索的频率范围\nu \约2-10 MHz的无线电发射的重要来源。
We report the first detection of an inverse Compton X-ray emission, spatially correlated with a very steep spectrum radio source (VSSRS), 0038-096, without any detected optical counterpart, in cluster Abell 85. The ROSAT PSPC data and its multiscale wavelet analysis reveal a large scale (linear diameter of the order of 500 h^{-1}_{50} kpc), diffuse X-ray component, in excess to the thermal bremsstrahlung, overlapping an equally large scale VSSRS. The primeval 3 K background photons, scattering off the relativistic electrons can produce the X-rays at the detected level. The inverse Compton flux is estimated to be (6.5\pm 0.5) 10^{-13} erg s^{-1}cm^{-2} in the 0.5-2.4 keV X-ray band. A new 327 MHz radio map is presented for the cluster field. The synchrotron emission flux is estimated to be (6.6\pm 0.90) \times 10^{-14} erg s^{-1} cm^{-2} in the 10-100 MHz radio band. The positive detection of both radio and X-ray emission from a common ensemble of relativistic electrons leads to an estimate of (0.95\pm 0.10) 10^{-6} G for the cluster-scale magnetic field strength. The estimated field is free of the `equipartition' conjecture, the distance, and the emission volume. Further, the radiative fluxes and the estimated magnetic field imply the presence of `relic' (radiative lifetime > 10^{9} yr) relativistic electrons with Lorentz factors \gamma \approx 700-1700, that would be a significant source of radio emission in the hitherto unexplored frequency range \nu \approx 2-10 MHz.