Runaway positrons in tokamak plasmas

Paper in proceeding, 2012

Runaway positrons can be produced in the presence of runaway electron avalanches in magnetized plasmas. Almost all the positrons generated by avalanching runaways will run away and are expected to have lifetimes of several seconds. For an avalanching positron distribution typical of tokamak plasmas the maximum of the synchrotron radiation spectrum should be around a micron. The radiated power is sensitive to many plasma parameters, specially the number of impurities, temperature and density. Apart from its intrinsic interest, detection of radiation from positrons could be a diagnostic tool to understand the properties of the annihilation medium.