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We investigate a possible origin for bursty radio emission observed on the active M dwarf V374 Peg, combining data-driven magnetic field modelling with archival radio light curves. We examine whether stellar prominence ejection can…

Solar and Stellar Astrophysics · Physics 2026-01-08 C. E. Brasseur , M. M. Jardine , S. Daley-Yates , J. F. Donati , J. Morin

Plasma emission (PE), i.e., electromagnetic radiation at the plasma frequency and its second harmonic, is a general process occurring in both astrophysical and laboratory plasmas. The prevailing theory presents a multi-stage process…

Plasma Physics · Physics 2021-05-05 Sulan Ni , Yao Chen , Chuanyang Li , Jicheng Sun , Hao Ning , Zilong Zhang

We use the cyclotron-maser theory to explain the core emission from the magnetosphere of pulsars. As a kind of direct and efficient maser type of emission, it can give rise to escaping radiation with extremely high brightness temperature…

Astrophysics · Physics 2009-10-30 Chun-yu Ma , Ding-yi Mao , De-yu Wang , Xin-ji Wu

'Main-sequence radio pulse-emitters' (MRPs) are magnetic early-type stars from which periodic radio pulses, produced via electron cyclotron maser emission (ECME), are observed. Despite the fact that these stars can naturally offer suitable…

We study the conditions for coherent radiation of an electron bunch driven by a counterpropagating strong pulsed electromagnetic plane wave. We derive the spectrum of the coherent radiation and show that it is emitted backwards with respect…

Plasma Physics · Physics 2024-04-17 Evgeny Gelfer , Alexander Fedotov , Ondrej Klimo , Stefan Weber

Although pulsars can radiate electromagnetic wave from radio to gamma ray bands, we still have no a united model to understand the multi-band emission. In this paper the effort for a joint model is presented. The inverse Compton scattering…

Astrophysics · Physics 2007-05-23 G. J. Qiao , K. J. Lee , H. G. Wang , R. X. Xu

Recent results from the PAMELA satellite indicate the presence of a large flux of positrons (relative to electrons) in the cosmic ray spectrum between approximately 10 and 100 GeV. As annihilating dark matter particles in many models are…

Astrophysics · Physics 2010-04-15 Dan Hooper , Pasquale Blasi , Pasquale Dario Serpico

The power of second harmonic electromagnetic emission is calculated for the case when strong plasma turbulence is excited by a powerful electron beam in a magnetized plasma. It is shown that the simple analytical model of strong plasma…

Plasma Physics · Physics 2012-05-21 I. V. Timofeev

A review is given for cyclotron resonant interactions in space plasmas. After giving a simple formulation for the test particle approach, illustrative examples for resonant interactions are given. It is shown that for obliquely propagating…

High Energy Astrophysical Phenomena · Physics 2012-11-14 T. Terasawa , S. Matsukiyo

High-energy cosmic ray air-showers have been known for over 30 years to emit strong radio pulses in the regime between a few and several 100 MHz (Allan 1971). To date, however, a thorough analysis of the emission mechanisms has not yet been…

Astrophysics · Physics 2007-05-23 Tim Huege , Heino Falcke

Firm evidence for a radio emission counterpart of cosmic ray air showers is presented. By the use of an antenna array set up in coincidence with ground particle detectors, we find a collection of events for which both time and arrival…

In this paper, electromagnetic emissions produced in a thin beam-plasma system are studied using two-dimensional particle-in-cell simulations. For the first time, the problem of emission generation in such a system is considered in the…

Plasma Physics · Physics 2016-05-25 V. V. Annenkov , I. V. Timofeev , E. P. Volchok

Recently, coherent radio emission has been discovered from a number of hot magnetic stars, via the process of electron cyclotron maser emission (ECME). This emission, observed in the form of highly circularly polarized pulses, have…

Solar and Stellar Astrophysics · Physics 2020-07-15 Barnali Das , Surajit Mondal , Poonam Chandra

The pulsar radio emission is commonly associated with the plasma outflow in the open field line tube; then a pencil beam is emitted along the pulsar magnetic axis. Observations suggest that there is an additional radio emission mechanism…

High Energy Astrophysical Phenomena · Physics 2018-12-12 Yuri Lyubarsky

We present the numerical simulations for an electron-beam-driven and loss-cone-driven electron-cyclotron maser (ECM) with different plasma parameters and different magnetic field strengths for a relatively small region and short time-scale…

Solar and Stellar Astrophysics · Physics 2015-06-04 S. Yu , J. G. Doyle , A. Kuznetsov , G. Hallinan , A. Antonova , A. L. MacKinnon , A. Golden

We observe the two- and three-pulse photon echo emission from a scattering powder, obtained by grinding a Pr$^{3+}$:Y$_2$SiO$_5$ rare earth doped single crystal. We show that the collective emission is coherently constructed over several…

Radio observations of cataclysmic variables have revealed a variety of behavior. From some systems, we see bright unpolarized radio flares occurring during dwarf nova outbursts, consistent with synchrotron emission from jets. In others, we…

High Energy Astrophysical Phenomena · Physics 2026-05-05 Margaret E. Ridder , Paul E. Barrett , Craig O. Heinke , Gregory R. Sivakoff

Emission process of a charged particle propagating in a medium with a curved magnetic field is considered. This mechanism combines features of conventional Cherenkov and curvature emission. Thus, presence of a medium with the index of…

High Energy Astrophysical Phenomena · Physics 2015-06-22 George Machabeli , Nino Chkheidze

The understanding of pulsar radio emission demands a close look at all regions of the huge parameter space present for pulsar observations. In this review we concentrate on the space given by the range of observed pulse periods, spanning…

Astrophysics · Physics 2007-05-23 M. Kramer

When gamma-rays emerge from a central source they may undergo Compton scattering in surrounding matter. The resulting Compton-scattered electrons radiate. Coherent radiation by such Compton electrons follows nuclear explosions above the…

Astrophysics · Physics 2007-05-23 J. I. Katz