Ultrahigh-energy cosmic-ray signature in GRB 221009A

S Das, S Razzaque - Astronomy & Astrophysics, 2023‏ - aanda.org
The brightest long gamma-ray burst (GRB) detected so far by the Swift-BAT and Fermi-GBM
telescopes, GRB 221009A, provides an unprecedented opportunity for understanding the …

Hadronuclear interactions in the jet of low TeV luminosity AGN: Implications for the low-state very-high-energy gamma-ray emission

R Xue, ZR Wang, WJ Li - Physical Review D, 2022‏ - APS
In the study of radiation mechanisms of active galactic nuclei (AGN) jets, hadronuclear (pp)
interactions are commonly neglected, because the number density of cold protons in the jet …

Can the one-zone hadronuclear model explain the hard-TeV spectrum of BL Lac objects?

WJ Li, R Xue, GB Long, ZR Wang, S Nagataki… - Astronomy & …, 2022‏ - aanda.org
Context. The 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 …

Revisiting the proton synchrotron radiation in blazar jets: Possible contributions from x-ray to -ray bands

R Xue, ST Huang, HB **ao, ZR Wang - Physical Review D, 2023‏ - APS
The proton synchrotron radiation is considered as the origin of high-energy emission of
blazars at times. However, extreme physical parameters are often required. In this work, we …

Cosmogenic gamma-ray and neutrino fluxes from blazars associated with IceCube events

S Das, S Razzaque, N Gupta - Astronomy & Astrophysics, 2022‏ - aanda.org
Context. Blazars constitute the vast majority of extragalactic γ-ray sources. They can also
contribute a sizable fraction of the diffuse astrophysical neutrinos detected by IceCube. In …

Implications of multiwavelength spectrum on cosmic-ray acceleration in blazar TXS 0506+ 056

S Das, N Gupta, S Razzaque - Astronomy & Astrophysics, 2022‏ - aanda.org
Context. The 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 …

Broadband Modeling of Low-luminosity Active Galactic Nuclei Detected in Gamma Rays

G Tomar, N Gupta, R Prince - The Astrophysical Journal, 2021‏ - iopscience.iop.org
Low-luminosity active galactic nuclei are more abundant and closer to us than the luminous
ones but harder to explore as they are faint. We have selected the four sources, NGC 315 …

Two components model for TeV -ray emission from extreme high-energy BL Lac objects

Q Dong, YG Zheng, CY Yang - Astrophysics and Space Science, 2021‏ - Springer
Extreme high-energy peaked BL Lac objects (EHBLs) are an emerging class of blazars with
exceptional spectral properties, eg, enhanced emission in the hard X-ray region and a hard …

[HTML][HTML] The Multimessenger Contribution of Ultra-High-Energy Cosmic Rays from Gamma-Ray Bursts

Z Li, F Min, Y **, Y Guo - Universe, 2025‏ - mdpi.com
It has long been debated whether gamma-ray bursts (GRBs) could serve as potential
sources of ultra-high-energy cosmic rays (UHECRs). In this study, we consider GRBs as …

Blazars Jets and Prospects for TeV-PeV Neutrinos and Gamma Rays Through Cosmic-Ray Interactions

R Sasse, RJ Costa, LA Stuani Pereira… - Brazilian Journal of …, 2025‏ - Springer
This study explores the origins of cosmic rays and their secondary messengers, focusing on
the potential role of four BL Lacs—W Comae, 1ES 1959+ 650, PKS 2005-489, and PKS …