Are both BL Lacs and pulsar wind nebulae the astrophysical counterparts of IceCube neutrino events
Are both BL Lacs and pulsar wind nebulae the astrophysical counterparts of IceCube neutrino events
复制标题
DOI：
10.1093/mnras/stu1166
复制
发表时间：
2014-06
影响因子：
4.8
通讯作者：
P. Padovani;E. Resconi
中科院分区：
文献类型：
--
作者：
P. Padovani;E. Resconi
冰立方最近报告说，通过全天空搜索发现了天体物理学来源的高能中微子。这些是有史以来探测到的宇宙射线相互作用中产生的最高能量粒子，开辟了研究PeV（10 - 15 eV）天空的可能性。到目前为止，由于它们的位置不确定性相当大，这些事件还没有与任何天体物理源相关联。我们已经找到了合理的天文对应的GeV-TeV波段，通过使用联合空间和能量信息。也就是说，我们在现有的大面积高能γ射线目录（TeVCat，WHSP，1FHL）中寻找IceCube事件的中值角误差圆内的源。然后，我们建立了这些源的光谱能量分布，并将其与相应中微子事件的能量和通量进行了比较。可能的对应物包括“经典”BL拉克，如MKN 421、PG 1553+113和H 2356 309，以及银河系脉冲星风星云，即MGRO J1908+06和HESS J1809 193。这可能表明银河系和河外中微子源的混合场景的出现。一方面，大量的天体，包括星暴星系NGC 253和半人马座A，尽管在空间上与中微子事件重合，但由于它们太弱而无法与中微子通量相协调，并且比相同误差圆中的其他BL拉克和银河系源弱得多，因此未能通过能量诊断。另一方面，由于缺乏TeV的数据，各种GeV的强大物体甚至不能被评估为可能的对手。高能天体物理中微子和这里挑选出来的候选者之间的明确联系将得到更多TeV观测的显着帮助，但只有通过进一步即将到来的IceCube观测才能证实或反驳。无论如何，这将对耀变体喷流、高能天体物理学、宇宙射线和中微子天文学产生重大影响。
IceCube has recently reported the discovery of high-energy neutrinos of astrophysical origin from an all-sky search. These are the highest energy particles produced in cosmic ray interactions ever detected, opening up the possibility of investigating the PeV (10 15 eV) sky. Up to now, because of their rather large positional uncertainties, these events have not been associated to any astrophysical source. We have found plausible astronomical counterparts in the GeV – TeV band by using joint spatial and energetic information. Namely, we looked for sources in the available large area high-energy γray catalogues (TeVCat, WHSP, 1FHL) within the median angular error circles of the IceCube events. We then built the spectral energy distribution of these sources and compared it with the energy and flux of the corresponding neutrino events. The likely counterparts include “classic” BL Lacs, such as MKN 421, PG 1553+113, and H 2356 309 as well as Galactic pulsar wind nebulae, namely MGRO J1908+06 and HESS J1809 193. This might indicate the emerging of a mixed scenario of Galactic and extra-galactic neutrino sources. On the one hand, a large number of objects, including the starburst galaxy NGC 253 and Centaurus A, despite being spatially coincident with neutrino events, fail the energetic diagnostic as they are too weak to be reconciled with the neutrino flux and much weaker than other BL Lacs and Galactic sources in the same error circles. On the other hand, various GeV powerful objects cannot be even assessed as possible counterparts due to their lack of TeV data. The definitive association between high-energy astrophysical neutrinos and the candidates singled out here will be significantly helped by more TeV observations but will be confirmed or disproved only by further upcoming IceCube observations. Either way, this will have momentous implications for blazar jets, high-energy astrophysics, and cosmic-ray and neutrino astronomy.