高能中微子辐射背景对潮汐瓦解事件黑洞质量限制的研究

Constraints on TDE Black Hole Mass by Diffused High Energy Neutrino Background

摘要: 潮汐瓦解事件(简称TDE)是一种发生在黑洞周围的高能天体物理事件，它被认为是探测宁静星系中心黑洞的探针，同时也是高能宇宙线和高能中微子的辐射源之一。在本文中，我们首先假设IceCube观测上的高能中微子辐射背景源于潮汐瓦解事件，通过构建潮汐瓦解事件产生的高能中微子辐射模型，拟合观测数据，对发生潮汐瓦解事件的黑洞质量参数空间和物理性质进行限制。最优拟合模型表明，黑洞质量区间为 时，喷流型TDE所产生的高能中微子辐射贡献了观测上辐射背景能量峰值处的主要流量。这意味着喷流型TDE与黑洞质量大小的反相关关系，以及这也暗示着也许依旧存在大量具有喷流的潮汐瓦解事件尚未被发现。此外，该最优模型首次定量地给出，质量区间涵括中等质量黑洞范围的随红移演化的黑洞质量函数，其大小正比于(1 + z)^−2.667。

Abstract: Tidal Disruption Event (TDE) is one of the high-energy astrophysical events that occur around black holes. They are considered as probes of detecting black holes at the centers of quiescent galaxies, as well as sources of high-energy cosmic rays and high-energy neutrinos. In this paper, we firstly assume that the high-energy neutrino flux background observed by IceCube collaboration originated from TDEs. By constructing the TDE-produced high-energy neutrino model and fitting it to observation data, we constrain the lower limit of black hole mass and other black hole mass dependent parameters which are related to the jet fraction of TDEs and redshift-evolved black hole mass function. Our optimal model shows that when the TDE mass lies in the range of , the high-energy neutrino flux produced by jet TDEs, which dominantly contributes the peak flux of neutrino background. It also implies an anti-correlation between jet fraction of TDEs and their black hole mass, this may indicate that a large number of jet-TDEs at the low-mass end are still unveiling. In addition, our model also firstly gives the redshift-dependent evolutional index of black hole mass function, which covers the intermediate mass range that is greater than , its value is proportional to (1 + z)^−2.667.