This, the November issue, completes the second volume of the Journal of Synchrotron Radiation (JSR). It is timely then to look back over the year and share some of our thoughts with you on the progress of the journal. We set out to establish JSR as the focus of the whole of the synchrotron radiation community and to accept only highquality papers covering sources, instrumentation, methods and a...

We model rapid variability of multifrequency emission from blazars occurring across the electromagnetic spectrum (from radio to gamma rays). Lower energy emission is produced by the synchrotron mechanism, whereas higher energy emission is due to inverse Compton scattering of the synchrotron emission. We take into account energy stratification established by particle acceleration at shock fronts...

The bright BL Lac object PKS 2005–489 was observed by BeppoSAX on November 1–2, 1998, following an active X–ray state detected by RossiXTE. The source, detected between 0.1 and 200 keV, was in a very high state with a continuum well fitted by a steepening spectrum due to synchrotron emission only. Our X–ray spectrum is the flattest ever observed for this source. The different X–ray spectral slo...

The idea of a pulsed magnet ring, fundamental to the synchrotron, appeared in a proposal by Oliphant [1] in 1943 and was followed by the independent discovery of phase stability by Veksler [2] in 1944 and McMillan [3] in 1945. This opened the door to a demonstration of synchrotron acceleration to 8 MeV by Goward and Barnes [4] in a converted betatron at Woolwich Arsenal, UK. The event, which to...

The hierarchical clustering observed in cold dark matter simulations result in highly clumped galactic halos. If the dark matter in our Halo is made of weakly interacting massive particles (WIMPs), their annihilation products should be detectable in the higher density and nearby clumps. We consider WIMPs to be neutralinos and calculate the synchrotron flux from their annihilation products in th...

We discuss the synchrotron radiation flux from the Galactic center in unstable dark matter scenario. Motivated by the anomalous excess of the positron fraction recently reported by the PAMELA collaboration, we consider the case that the dark matter particle is unstable (and long-lived), and that energetic electron and positron are produced by the decay of dark matter. Then, the emitted e± becom...