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Klein-Nishina effects in the spectra of non-thermal sources immersed in external radiation fields [PDF]
Monthly Notices of the Royal Astronomical Society, 2005 We study Klein-Nishina (KN) effects in the spectrum produced by a steady state, non-thermal source where rapidly accelerated electrons cool by emitting synchrotron radiation and Compton upscattering ambient photons produced outside the source. We focus on the case where the radiation density inside the source exceeds that of the magnetic field. We show
Rafal Moderski +2 more
exaly +7 more sources
Particle Injection and Nonthermal Particle Acceleration in Relativistic Magnetic Reconnection
The Astrophysical Journal, 2023 Magnetic reconnection in the relativistic regime has been proposed as an important process for the efficient production of nonthermal particles and high-energy emission. Using fully kinetic particle-in-cell simulations, we investigate how the guide-field
Omar French +3 more
doaj +1 more source
The Ultraviolet C ii Lines as a Diagnostic of κ-distributed Electrons in Planetary Nebulae
The Astrophysical Journal, 2022 Non-Maxwellian κ electron energy distributions (EEDs) have been proposed in recent years to resolve the so-called “electron temperature and abundance discrepancy problem” in the study of planetary nebulae (PNs).
Zheng-Wei Yao, Yong Zhang
doaj +1 more source
The Astrophysical Journal, 2023 Blazar emission is dominated by nonthermal radiation processes that are highly variable across the entire electromagnetic spectrum. Turbulence, which can be a major source of nonthermal particle acceleration, can widely exist in the blazar emission ...
Haocheng Zhang +5 more
doaj +1 more source
A Geometric Model to Interpret the γ-Ray Quasiperiodic Oscillation of PG 1553+113
The Astrophysical Journal, 2023 We propose a jet helical motion model to explain the γ -ray quasiperiodic oscillation of PG 1553+113. In this model, we hypothesize that a relativistic jet with constant angular velocity rotates around the axis, causing the Doppler factor of the jet to ...
Quan-Gui Gao +6 more
doaj +1 more source
The Astrophysical Journal, 2023 Cosmology models predict that external accretion shocks form in the outer region of galaxy clusters owing to supersonic gas infall from filaments and voids in the cosmic web. They are characterized by high sonic and Alfvénic Mach numbers, M _s ∼ 10–10 ^2
Ji-Hoon Ha, Dongsu Ryu, Hyesung Kang
doaj +1 more source
Polarization Angle Orthogonal Jumps in Fast Radio Bursts
The Astrophysical JournalRecently, polarization angle (PA) orthogonal jumps over millisecond timescales were discovered from three bursts of the repeating fast radio burst source FRB 20201124A by the FAST telescope.
Yuanhong Qu, Bing Zhang, Pawan Kumar
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Coherent Inverse Compton Scattering in Fast Radio Bursts Revisited
The Astrophysical JournalGrowing observations of temporal, spectral, and polarization properties of fast radio bursts (FRBs) indicate that the radio emission of the majority of bursts is likely produced inside the magnetosphere of its central engine, likely a magnetar.
Yuanhong Qu, Bing Zhang
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The Origins of Narrow Spectra of Fast Radio Bursts
The Astrophysical JournalObservations find that some fast radio bursts (FRBs) have extremely narrowband spectra, i.e., Δ ν / ν _0 ≪ 1. We show that, when the angular size of the emission region is larger than the Doppler beaming angle, the observed spectral width (Δ ν / ν _0 ...
Pawan Kumar, Yuanhong Qu, Bing Zhang
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Multiwavelength Variability and Jet Properties of Low-synchrotron-peaked BL Lacertae Objects
The Astrophysical JournalLow-synchrotron-peaked BL Lac objects (LBLs) are promising candidates for masquerading BL Lacs, and the mechanism responsible for their high-energy γ -ray emission still requires further investigation.
R. X. Zhou +4 more
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