EXPECTED GAMMA-RAY EMISSION OF SUPERNOVA REMNANT SN 1987A
EXPECTED GAMMA-RAY EMISSION OF SUPERNOVA REMNANT SN 1987A
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超新星遗迹 SN 1987A 的预期伽马射线发射
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
H. Völk
中科院分区：
文献类型：
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作者：
E. Berezhko;L. Ksenofontov;H. Völk
采用超新星遗迹 (SNR) 中宇宙射线 (CR) 加速的非线性动力学理论来重新检查 SN 1987A 遗迹在 5-100 年的延长演化周期内的非热特性。结果表明，核 CR 的有效产生会导致外部 SNR 激波的强烈修改，并产生大的下游磁场 Bd ≈ 20 mG。需要激波修正和强场来产生观察到的陡峭的无线电发射光谱，以及高能电子的大量同步加速器冷却，这会减少它们的 X 射线同步加速器通量。这些特征也与现有的X射线观测结果一致。在对整体磁场拓扑和该场的湍流扰动的合理假设下，当前历元 TeV 能量的预期 γ 射线能量通量接近 ϵγFγ ≈ 4 × 10−13 erg cm2 s−1。预计源头的总体非热强度在未来 15-20 年内将增加大约两倍；此后，它应该以长期的形式随着时间的推移而减少。
A nonlinear kinetic theory of cosmic ray (CR) acceleration in supernova remnants (SNRs) is employed to re-examine the nonthermal properties of the remnant of SN 1987A for an extended evolutionary period of 5–100 yr. It is shown that an efficient production of nuclear CRs leads to a strong modification of the outer SNR shock and to a large downstream magnetic field Bd ≈ 20 mG. The shock modification and the strong field are required to yield the steep radio emission spectrum observed, as well as the considerable synchrotron cooling of high-energy electrons which diminishes their X-ray synchrotron flux. These features are also consistent with the existing X-ray observations. The expected γ-ray energy flux at TeV energies at the current epoch is nearly ϵγFγ ≈ 4 × 10−13 erg cm2 s−1 under reasonable assumptions about the overall magnetic field topology and the turbulent perturbations of this field. The general nonthermal strength of the source is expected to increase roughly by a factor of two over the next 15–20 years; thereafter, it should decrease with time in a secular form.