• C. Gabor
  STFC/RAL/ASTeC, Chilton, Didcot, Oxon
• G.A. Blair, G.E. Boorman, A. Bosco
  Royal Holloway, University of London, Surrey
• A.P. Letchford
  STFC/RAL/ISIS, Chilton, Didcot, Oxon

The front end test stand FETS is an R&D project hosted at Rutherford Appleton Laboratory RAL with its aim to demonstrate a high power, fast chopped H^- ion beam and will consist in final stage of ion source, low energy beam transport LEBT, RFQ and a transport line including a chopper system at 3MeV output energy. Possible candidates of applications are Isis upgrade (RAL neutron source), future spallation sources or the Neutrino factory. The high beam power may cause problems due to its thermal power deposition on diagnostics parts introduced into the beam so non-interceptive beam instruments are highly preferred to avoid those problems. Diagnostics for H^- beams can benefit of laser light where photons with suitable energy are able to detach the additional electron. This method is applied to a beam profile monitor close to the ion source of the FETS beam line and the paper gives a status report of the ongoing process of commissioning and provides a detailed discussion of problems and recent changes including first "proof-of-principle" measurements.