arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2109.02648astro-ph.HE
收藏

是什么为TDE AT2019dsg中的无线电发射提供动力:长寿的喷流还是破坏本身?

What powers the radio emission in TDE AT2019dsg: a long-lived jet or the disruption itself?

Tatsuya Matsumoto, Tsvi Piran, Julian H. Krolik

摘要:

潮汐破裂事件AT2019dsg从无线电到X射线都被观测到,可能伴随着高能中微子。以前的解释集中在一个中央发动机作为无线电发射的能量来源的持续注入。我们表明,连续的能量注入是不必要的,无线电数据可以解释由一个单一的喷射等离子体,提供所需的所有能量。为了支持这一论断,我们分析了同步辐射自吸收光谱的均分模型。类似于以前的分析,我们发现,在无线电发射区域的能量增加约$\propto t^{0.7}$和该区域的长度规模增长$\propto t$的速度$\simeq0.06c$。这一事件类似于超新星遗迹的最早阶段:因为喷出的质量比冲击的外部质量大得多,它的速度保持不变,而冲击气体的能量随着时间的推移而增长。无线电发射材料从流出物获得能量,而不是中心物体继续注入能量。虽然不能完全排除吸积黑洞的能量注入,但能量注入率与回退光度有很大不同,保持恒定的外流速度需要微调,需要进一步的物理解释。如果中微子关联是真实的,则所需的能量注入要比射电辐射大得多,这表明探测到的中微子不是来自射电辐射区。

英文摘要:

The tidal disruption event AT2019dsg was observed from radio to X-rays and was possibly accompanied by a high-energy neutrino. Previous interpretations have focused on continued injection by a central engine as the source of energy for radio emission. We show that continuous energy injection is unnecessary; the radio data can be explained by a single ejection of plasma that supplies all the energy needed. To support this assertion, we analyze the synchrotron self-absorbed spectra in terms of the equipartition model. Similar to previous analyses, we find that the energy in the radio-emitting region increases approximately $\propto t^{0.7}$ and the lengthscale of this region grows $\propto t$ at a rate $\simeq0.06c$. This event resembles the earliest stage of a supernova remnant: because the ejected mass is much greater than the shocked external mass, its velocity remains unchanged, while the energy in shocked gas grows with time. The radio-emitting material gains energy from the outflow, not continuing energy injection by the central object. Although energy injection from an accreting BH cannot be completely excluded, the energy injection rate is very different from the fallback luminosity, and maintaining constant outflow velocity requires fine-tuning demanding further physical explanation. If the neutrino association is real, the energy injection needed is much greater than for the radio emission, suggesting that the detected neutrino did not arise from the radio-emitting region.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑