A $\gamma$-Ray Emitting Blazar at Redshift 3.64: Fermi-LAT and OVRO Observations of PKS 0201+113

Autor: Lei, Hai, Zhang, Ying-Kang, Jiang, Xiong, Kiehlmann, Sebastian, Readhead, Anthony C. S., Chen, Liang, Liao, Neng-Hui, An, Tao
Rok vydání: 2024
Předmět:
Druh dokumentu: Working Paper
Popis: High-redshift ($z >3$) $\gamma$-ray blazars are rare, but they are crucial for our understanding of jet evolution, $\gamma$-ray production and propagation, and the growth of supermassive black holes in the early universe. A new analysis of Fermi-LAT data reveals a significant (5$\sigma$), spectrally soft ($\Gamma \simeq$ 3.0) $\gamma$-ray source in a specific 4-month epoch, cospatial with PKS 0201+113 ($z$ = 3.64). Monitoring of PKS 0201+113 at 15 GHz by the Owens Valley Radio Observatory 40 m Telescope from 2008 to 2023 shows a prominent flare that dominates the radio light curve. The maximum of the radio flare coincides with the $\gamma$-ray flare, strongly suggesting an association ($\textrm{p-value}=0.023$) between the $\gamma$-ray and the radio sources. PKS 0201+113 is only the third $\gamma$-ray blazar to be identified with $z> 3.5$, and it is the first such object to be identified by the detection of quasi-simultaneous $\gamma$-ray and radio flares. The jet properties of this peculiar blazar have been investigated. A detailed study of a two-zone leptonic model is presented that fits the broadband spectral energy distribution. An alternative scenario is also briefly discussed.
Comment: 22 pages, 6 figures, 2 Tables, accepted for publication in ApJ
Databáze: arXiv