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Related papers: Particle Acceleration in Shearing Flows: Efficienc…

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Variability is a general property of accretion discs and their associated jets. We introduce a semi-analytic model for particle acceleration and radio jet/lobe evolution and explore the effect of Myr timescale jet variability on the…

High Energy Astrophysical Phenomena · Physics 2021-03-24 James H. Matthews , Andrew M. Taylor

We find the general requirements, set by classical electrodynamics, to the sources of extremely high-energy cosmic rays (EHECRs). It is shown that the parameters of EHECR accelerators are strongly limited not only by the particle…

We propose a new particle acceleration mechanism. Electron can be accelerated to relativistic energy within a few electromagnetic wave cycles through the mechanism which is named electromagnetic and magnetic field resonance acceleration…

Plasma Physics · Physics 2007-05-23 Hong Liu , X. T. He , S. G. Chen , W. Y. Zhang

We point out that even the most intense laser beams available today can provide only a very small fraction of the beam energy required to reach the design luminosity for a future e+e- linear collider. This fact seems to have been overlooked…

Accelerator Physics · Physics 2007-05-23 Adrian C. Melissinos

Relativistic magnetized jets from active galaxies are among the most powerful cosmic accelerators, but their particle acceleration mechanisms remain a mystery. We present a new acceleration mechanism associated with the development of the…

High Energy Astrophysical Phenomena · Physics 2018-12-19 E. Paulo Alves , Jonathan Zrake , Frederico Fiuza

We examine Fermi-type acceleration at relativistic shocks, and distinguish between the initial boost of the first shock crossing cycle, where the energy gain per particle can be very large, and the Fermi process proper with repeated shock…

Astrophysics · Physics 2009-10-31 Yves A. Gallant , Abraham Achterberg , John G. Kirk , Axel W. Guthmann

To investigate the efficiency of centrifugal acceleration of particles as a possible mechanism for the generation of ultra-high $\gamma$-ray nonthermal emission from TeV blazars, we study the centrifugal acceleration of electrons by…

Astrophysics · Physics 2009-11-11 Zaza Osmanov , Andria D. Rogava , Gianluigi Bodo

In the effort of achieving high-energetic ion beams from the interaction of ultrashort laser pulses with a plasma, volumetric acceleration mechanisms beyond Target Normal Sheath Acceleration have gained attention. A relativisticly intense…

Direct laser acceleration has proven to be an efficient source of high-charge electron bunches and high brilliance X-rays. However, an analytical description of the acceleration in the interaction with varying plasma density targets is…

Plasma Physics · Physics 2024-12-19 Robert Babjak , Bertrand Martinez , Miroslav Krus , Marija Vranic

We have investigated particle acceleration and emission from shocks and shear flows associated with an unmagnetized relativistic jet plasma propagating into an unmagnetized ambient plasma. Strong electro-magnetic fields are generated in the…

High Energy Astrophysical Phenomena · Physics 2014-12-23 K. -I. Nishikawa , P. Hardee , I. Dutan , B. Zhang , A. Meli , E. J. Choi , K. Min , J. Niemiec , Y. Mizuno , M. Medvedev , A. Nordlund , J. T. Frederiksen , H. Sol , M. Pohl , D. Hartmann

Recent studies have demonstrated the possibility of accelerating electrons to MeV energies in ambient air using tightly focused laser configurations. In this article, we explore possible strategies to control and optimize the resulting…

We show that an extragalactic jet with a velocity shear gives rise to Fermi like acceleration process for photons scattering withing the shear layers of the jet. Such photons then gain energy to produce a high energy power law. These power…

High Energy Astrophysical Phenomena · Physics 2024-11-20 Mukesh Kumar Vyas , Asaf Pe'er

We study the generation and space-time evolution of fluid acceleration in heavy-ion collisions using AMPT and UrQMD transport models combined with a Gaussian smearing method. The peak proper acceleration reaches several hundred MeV, with…

Nuclear Theory · Physics 2026-04-02 Song-Ze Zhong , Xian-Gai Deng , Xu-Guang Huang , Yu-Gang Ma

A new laser-proton acceleration structure combined by two relativistic electron shells, a suprathermal electron shell and a thermal electron cloud is proposed for $a\gtrapprox80\sigma_0$, where a is the normalized laser field and $\sigma_0$…

Plasma Physics · Physics 2011-12-13 Yongsheng Huang , Naiyan Wang , Xiuzhang Tang , Yijin Shi , Zhang Shan

The nature of the intense X-ray emission from powerful extragalactic jets at large ($>1$ kpc) scale is still debated. The scenario that invokes the inverse Compton scattering of the CMB by electrons is challenged by the lack of gamma-ray…

High Energy Astrophysical Phenomena · Physics 2021-01-13 F. Tavecchio

A simple model of cosmic ray electron acceleration at the jet boundary (Ostrowski 2000) yields a power-law particle energy distribution of ultrarelativistic electrons with an energy cut-off growing with time and finally, a growing particle…

Astrophysics · Physics 2009-11-07 L. Stawarz , M. Ostrowski

We consider the centrifugal acceleration of charged test particles by rotating magnetospheres which are widely believed to be responsible for the relativistic jet phenomenon in active galactic nuclei (AGN). Based on an analysis of forces…

Astrophysics · Physics 2007-05-23 F. M. Rieger , K. Mannheim

It is suggested that the outflowing plasma in the jets of active galactic nuclei (AGNs) is inhomogeneous and consists of separate clouds. These clouds are strongly magnetized and move away from the central engine at relativistic speeds. The…

Astrophysics · Physics 2010-12-03 V. V. Usov , M. V. Smolsky

Laser-plasma acceleration produces ultrashort, high-brightness ion beams reaching tens of MeV, yet their large divergence and broad energy spread require dedicated capture elements for beam transport. Using laser-accelerated protons from…

Accelerator Physics · Physics 2026-05-12 Daniel C. E. Dewitt , Oliver Boine-Frankenheim , Abel Blazevic

We consider the stochastic acceleration of particles which results from resonant interactions with plasma waves in black hole magnetospheres. We calculate acceleration rates and escape time scales for protons and electrons resonating with…

Astrophysics · Physics 2009-10-28 Charles D. Dermer , James A. Miller , Hui Li