The KEK-PS Booster is a 40to 500-MeV proton synchrotron, which is the injector of the KEK 12 GeV Proton synchrotron, and also delivers a beam to the Booster Synchrotron Utilization Facility (BSF). It is a compact alternating-gradient synchrotron operated at fixed tunes. The repetition rate is 20Hz and the synchrotron magnets are excited by a resonance circuit. The linac beam is injected by char...

The radio emission of a galaxy consists of thermal bremsstrahlung, synchrotron emission from discrete supernova remnants, and diffuse synchrotron emission from cosmic ray electrons spread over the galactic disk and halo. Each of these components has a different spectral index so that the total radio spectral index of a galaxy depends sensitively on their relative contribution and on the process...

We demonstrate using linear theory and particle-in-cell (PIC) simulations that a synchrotron-cooling collisionless plasma acquires pressure anisotropy and, if the beta is sufficiently high, becomes unstable to firehose instability, in process we dub synchrotron instability (SFHI). The SFHI channels free energy from of radiating, relativistic electrons (and/or positrons) into small-amplitude, ki...

We investigate the polarization properties of Comptonized X-rays from relativistic jets in Active Galactic Nuclei (AGN) using Monte Carlo simulations. We consider three scenarios commonly proposed for the observed X-ray emission in AGN: Compton scattering of blackbody photons emitted from an accretion disk; scattering of cosmic microwave background (CMB) photons; and self-Comptonization of intr...

Aims. We investigate whether the high energy tail detected by the Fermi/LAT for the short GRB 081024B can be caused by synchrotron and self-Compton emission in the context of either the internal or external shock models. Methods. For the internal shock scenario, we explore the possibility of generating the high energy photons directly by means of the synchrotron process, or inverse Compton emis...

Working-group members: Massimo Altarelli, European Synchrotron Radiation Facility (France); Thomas Callcott, University of Tennessee Knoxville; C.T. Chen, Synchrotron Radiation Research Center (Taiwan); Jun-Liang Chen, Synchrotron Radiation Research Center (Taiwan); Jonathan Denlinger, University of Michigan; Makoto Doi, Lawrence Berkeley National Laboratory; Wolfgang Eberhardt, Forschungszentr...