发表机构
Centre for Space Research, North-West University（西北大学空间研究中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
针对与 IceCube-220225A 中微子事件位置相符的耀变体 PKS 0215+015，通过多波段观测与 SED 建模，发现其辐射以轻子过程主导，质子光度虽高但中微子通量偏低，并探讨了关联的可行性。
AI 中文摘要
高能天体物理中微子的探测为识别宇宙粒子加速器开辟了新途径。耀变体是活动星系核（AGN）的一种，其相对论性喷流方向接近观测者视线方向，被认为是能够产生 PeV 量级中微子的强子相互作用的理想场所。我们研究了平谱射电类星体（FSRQ）PKS 0215+015（红移 z ≃ 1.715），该源在位置上与估计能量约为 154 TeV 的 IceCube-220225A 中微子事件相符。我们结合 Fermi-LAT 的 γ 射线数据以及 Swift-XRT 和 Swift-UVOT 的观测，来表征该源在中微子事件时期的行为。PKS 0215+015 在 2022 年初表现出显著的 γ 射线、X 射线和光学活动，这与沿喷流传播的扰动一致。我们构建了耀发期间宽波段光谱能量分布（SED），并使用轻子模型和轻子-强子模型框架对其进行建模。该 SED 能被包含同步辐射、同步自康普顿和外部康普顿发射的轻子模型很好地重现，表明电子过程占主导。共同加速的质子成分在辐射上处于次主导地位，但所需的质子动能光度比磁场等分光度高约两个数量级。预测的中微子通量远低于单个 IceCube-220225A 类似探测所暗示的水平。对短期 γ 射线变率的独立分析得到的发射区尺寸与 SED 拟合结果一致，支持了模型的物理自洽性。我们讨论了 PKS 0215+015 与 IceCube-220225A 之间关联的时间与能量合理性，以及对高红移 FSRQ 未来多信使研究的意义。
英文摘要
The detection of high-energy astrophysical neutrinos has opened a new avenue for identifying cosmic particle accelerators. Blazars, active galactic nuclei (AGN) with relativistic jets oriented close to the observer's line of sight, are promising sites of hadronic interactions capable of producing PeV-scale neutrinos. We investigate the flat-spectrum radio quasar (FSRQ) PKS~0215+015 ($z \simeq 1.715$), positionally consistent with the \textit{IceCube-220225A} neutrino event of estimated energy $\sim$154~TeV. We combine \textit{Fermi}-LAT $γ$-ray data with Swift-XRT and Swift-UVOT observations to characterise the source around the neutrino epoch. PKS~0215+015 exhibited pronounced $γ$-ray, X-ray and optical activity in early 2022, consistent with a disturbance propagating along the jet. We construct broadband spectral energy distributions (SEDs) for the flaring interval and model them using leptonic and lepto-hadronic frameworks. The SED is well reproduced by a leptonic model comprising synchrotron, synchrotron self-Compton and external Compton emission, indicating that electron processes dominate. A co-accelerated proton population remains radiatively subdominant but requires a proton kinetic luminosity roughly two orders of magnitude above equipartition with the magnetic field. The predicted neutrino flux is well below that implied by a single \textit{IceCube-220225A}-like detection. Independent analysis of short-term $γ$-ray variability yields an emission-region size consistent with the SED fit, supporting the model's physical self-consistency. We discuss the temporal and energetic plausibility of the association between PKS~0215+015 and \textit{IceCube-220225A} and implications for future multimessenger studies of high-redshift FSRQs.
CommentsAccepted for publication in Journal of High Energy Astrophysics
