title: Determination of hydrogen/deuterium ratio with neutron measurements on MAST.
abstract: On MAST, compressional Alfvén eigenmodes can be destabilized by the presence of a sufficiently large population of energetic particles in the plasma. This dependence was studied in a series of very similar discharges in which increasing amounts of hydrogen were puffed into a deuterium plasma. A simple method to estimate the isotopic ratio nH/nD using neutron emission measurements is here described. The inferred isotopic ratio ranged from 0.0 to 0.6 and no experimental indication of changes in radial profile of nH/nD were observed. These findings are confirmed by TRANSP/NUBEAM simulations of the neutron emission.
authors.affiliation: Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden.
authors.forename: I
authors.initials: I
authors.lastname: Klimek
authors.affiliation: Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Cecconello
authors.affiliation: CCFE, Culham Science Centre, Abingdon, United Kingdom.
authors.forename: S E
authors.initials: SE
authors.lastname: Sharapov
authors.affiliation: CCFE, Culham Science Centre, Abingdon, United Kingdom.
authors.forename: J
authors.initials: J
authors.lastname: Harrison
authors.affiliation: Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Ericsson