A lower limit to the magnetic field in Cassiopeia-A
A lower limit to the magnetic field in Cassiopeia-A
复制标题
仙后座 A 的磁场下限
DOI：
10.1093/mnras/191.4.855
复制
发表时间：
1980
影响因子：
4.8
通讯作者：
S. Sarkar
中科院分区：
文献类型：
--
作者：
R. Cowsik;S. Sarkar
超新星遗迹仙后座-A的射电发射壳中的磁场强度应该比负责非热射电发射的电子的韧致辐射不超过最近观测设定的伽马射线发射率上限的磁场强度大。超新星激波对星际磁场的单纯压缩不可能产生这样的场强，而是由于膨胀壳层中的磁流体力学不稳定性而产生的。文中还简要讨论了周围HII区光子的逆康普顿散射产生的伽马射线。
The magnetic field strength in the radio-emitting shell of the supernova remnant Cassiopeia-A should be greater thanif the bremsstrahlung by the electrons responsible for the non-thermal radio emission is not to exceed the upper limits to the gamma-ray emissivity set by the recent observations. This field strength is shown to be too large to be generated by a mere compression of the interstellar field by the supernova shock but must arise due to magnetohydrodynamic instabilities in the expanding shell. Gamma-ray generation through inverse-Compton scattering of photons in the surrounding HIIregion is also briefly discussed.