由扭曲的不均喷流解释的Blazar光谱变异性
C M Raiteri1, M Villata1, J A Acosta-Pulido2,3
1INAF, Osservatorio Astrofisico di Torino, I-10025 Pino Torinese, Italy.
Nature
|December 7, 2017
概括
布拉扎星的变化,包括像CTA 102在2016-2017年发生的极端爆发,最好通过不均的,曲线变化的喷射方向来解释,从而验证了相对论辐射理论.
科学领域:
- 天体物理学和宇宙学
- 高能天体物理学
背景情况:
- 由于相对论喷流指向地球, 它们会发出强大的辐射.
- 由于多普勒辐射,布拉扎尔变异性是快速和明显的,但其潜在机制仍在争论中.
- 建议的机制包括粒子加速/冷却,冲击,流或几何效应,如改变视角.
研究的目的:
- 调查布拉萨变化的原因,特别是CTA 102中观察到的长期流量和光谱变化.
- 测试竞争型号的闪电辐射, 专注于物理条件与几何解释.
主要方法:
- 在长期的时间内对光电到无线电波长的监测.
- 对流量和光谱变化的长期趋势的分析.
- 将观测数据与理论预测进行比较,特别是与相对论辐射和喷射几何相关的数据.
主要成果:
- 在CTA 102中观察到的长期变异性最好解释为不均的曲线喷流,其方向随着时间的推移而改变.
- 2016年至2017年的极端光学爆发恰逢发射区域的视角较小.
- 喷射方向的变化会改变多普勒因子,影响观察到的流量和变化时间表.
结论:
- 这项研究支持由喷射方向变化驱动的气体变化的几何解释.
- 磁动力学不稳定性或喷气旋转被认为是这些方向变化的原因.
- 这些发现进一步证实了在Blazar发射中的相对论辐射理论.
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