Can the one-zone hadronuclear model explain the hard-TeV spectrum of BL Lac objects?
Can the one-zone hadronuclear model explain the hard-TeV spectrum of BL Lac objects?
复制标题
单区强核模型能否解释 BL Lac 天体的硬 TeV 光谱？
DOI：
10.1051/0004-6361/202142051
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发表时间：
2022
影响因子：
6.5
通讯作者：
Jian Cheng
中科院分区：
文献类型：
--
作者：
Li;Wei-Jian; Xue;Rui; Long;Guang-Bo; Wang;ZeRui; Nagataki;Shigehiro; Yan;Da-Hai; Wang;Jian Cheng
一些 BL Lacs 的本征 TeV 发射在校正河外背景光后具有硬光谱（硬 TeV 光谱）的特征。硬TeV光谱对传统的一区模型，包括轻子模型、光强模型、质子同步加速器模型等提出了挑战。目的在这项工作中，我们旨在研究一区强核（pp）模型是否可以在不引入极端参数的情况下解释BL Lacs的硬TeV光谱。方法我们提供解析计算，可用于研究是否存在参数空间以及电荷是否存在在不引入超爱丁顿射流功率的情况下解释BL Lacs的硬TeV谱时，可以满足射流的中性条件。结果我们发现，在之前收集的硬TeV BL Lacs样品中，只有1ES 0229+200的硬TeV谱可以用pp相互作用中产生的π0衰变的γ射线来解释，但代价是设置比史瓦西半径小的辐射区域半径的中心黑洞。结合我们的研究结果和之前其他单区模型的研究结果，我们认为 BL Lacs 的硬 TeV 光谱不能在不引入极端参数的情况下用单区模型来解释，而应该起源于多个辐射区域。
ContextThe intrinsic TeV emission of some BL Lacs is characterized by a hard spectrum (the hard-TeV spectrum) after correcting for the extragalactic background light. The hard-TeV spectra pose a challenge to conventional one-zone models, including the leptonic model, the photohadronic model, the proton synchrotron model, and others.AimsIn this work, we aim to investigate whether or not the one-zone hadronuclear (pp) model can be used to interpret the hard-TeV spectra of BL Lacs without introducing extreme parameters.MethodsWe provide analytical calculations that can be used to study whether or not there is a parameter space, and whether or not the charge neutrality condition of the jet can be satisfied when interpreting the hard-TeV spectra of BL Lacs without introducing a super-Eddington jet power.ResultsWe find that in a sample of hard-TeV BL Lacs previously collected, only the hard-TeV spectrum of 1ES 0229+200 can be explained byγ-rays fromπ0decay produced in theppinteractions, but at the cost of setting a small radius of the radiation region than the Schwarzschild radius of the central black hole. Combining our findings with those of previous studies of other one-zone models, we suggest that the hard-TeV spectra of BL Lacs cannot be explained by a one-zone model without introducing extreme parameters, and should originate from the multiple radiation regions.