论文标题
多波长光谱对Blazar TXS 0506+056中宇宙射线加速度的影响
Implications of multiwavelength spectrum on cosmic-ray acceleration in blazar TXS 0506+056
论文作者
论文摘要
魔术合作最近分析了$γ$ -Ray Blazar TXS 0506+056的长期多波长运动中的数据。 2018年12月，它在高能（vhe; $ e> 100 $ gev）$γ$ -Ray乐队中燃烧，但未检测到同时的中微子活动。我们使用单区Leptohadronic发射对观察到的光谱能分布（SED）进行建模。我们通过观察到的X射线通量在二射线辐射引起的X射线通量的限制中估计中微子通量，该X射线通量是由具有能量$ e_p \ e_p \ Lessim 0.1 $ eev的质子引发的。我们假设超能量宇宙射线（UHECRS; $ e \ gtrsim0.1 $ eev），具有与低能频谱相同的斜率和归一化，在喷气机中加速了，但有效地逃脱了。我们以随机的湍流外磁场（EGMF）传播UHE质子。射流的松性发射主导着GEV范围，而射流中CR相互作用的级联发射对X射线和VHE范围产生了很大贡献。来自UHECRS的视线宇宙基因$γ$射线在VHE频谱中产生了硬化。我们对喷气中微子对中微子的模型预测与IceCube的7.5年通量限制一致，并且在魔术运动中没有显示可变性。因此，我们推断GEV-TEV $γ$ - 砂与中微子火光之间的相关性很小。 CRS中的发光度限制了宇宙$γ$ -Ray通量，从而将EGMF的RMS值范围限制为$ \ gtrsim 10^{ - 5} $ ng。宇宙基因中微子通量低于10年观察的Icecube-gen2检测潜力。 VHE $γ$ -Ray的可变性应来自喷气机内活动的增加；因此，在多TEV能量下检测稳定通量可能表明UHECR加速度。即将到来的$γ$ ray成像望远镜（例如CTA）将能够限制TXS 0506+056 SED中的宇宙基因$γ$ -Ray组件。
MAGIC collaboration has recently analyzed data from a long-term multiwavelength campaign of the $γ$-ray blazar TXS 0506+056. In December 2018, it was flaring in the very-high-energy (VHE; $E>100$ GeV) $γ$-ray band, but no simultaneous neutrino event was detected. We model the observed spectral energy distribution (SED), using a one-zone leptohadronic emission. We estimate the neutrino flux through the restriction from observed X-ray flux on the secondary radiation due to hadronic cascade, initiated by protons with energy $E_p \lesssim 0.1$ EeV. We assume ultrahigh-energy cosmic rays (UHECRs; $E\gtrsim0.1$ EeV), with the same slope and normalization as the low-energy spectrum, are accelerated in the jet but escape efficiently. We propagate the UHE protons in a random, turbulent extragalactic magnetic field (EGMF). The leptonic emission from the jet dominates the GeV range, whereas the cascade emission from CR interactions in the jet contributes substantially to the X-ray and VHE range. The line-of-sight cosmogenic $γ$ rays from UHECRs produce a hardening in the VHE spectrum. Our model prediction for neutrinos from the jet is consistent with the 7.5-year flux limit by IceCube and shows no variability during the MAGIC campaign. Therefore, we infer that the correlation between GeV-TeV $γ$-rays and neutrino flare is minimal. The luminosity in CRs limits the cosmogenic $γ$-ray flux, which, in turn, bounds the RMS value of the EGMF to $\gtrsim 10^{-5}$ nG. The cosmogenic neutrino flux is lower than the IceCube-Gen2 detection potential for 10 yrs of observation. VHE $γ$-ray variability should arise from increased activity inside the jet; thus, detecting steady flux at multi-TeV energies may indicate UHECR acceleration. Upcoming $γ$-ray imaging telescopes such as the CTA will be able to constrain the cosmogenic $γ$-ray component in the SED of TXS 0506+056.
