First Measurements of Charged Fusion Products in MAST-Upgrade*

We present first measurements of protons and tritons from the d(d,p)t reaction in MAST-U. The presented data were taken during the  MAST-U03 experimental campaign with an upgraded version of the Proton Detector previously used at MAST (Perez et al., 2014).

The detector array consists of 3 collimated silicon based surface barrier detectors with a depletion depth of 300μm and a collimated 120μm thick diamond detector. This array measures the energy of unconfined energetic 3 MeV protons and 1 MeV tritons produced primarily during  neutral beam injection (NBI) heating. This instrument provides information on the fast ion distribution function and how it is affected by various plasma instabilities. Being able to take data simultaneously with silicon and diamond based detectors allows one to directly compare the performance of these two detectors. The applicability of diamond detectors in fusion plasmas is of great interest as they promise to be much more radiation resistant compared to silicon detectors and much less sensitive to temperature variations. The detector has been mounted on the MAST-U Reciprocating Probe arm (RP). The measured energy spectra and particle rates will be compared to FIDASIM and TRANSP calculations.