Proton beam profile monitor using synchrotron light

Theoretical studies, followed by experiments, show that owing to the abrupt change of the magnetic field occurring at the magnet edges, synchrotron radiation is emitted in the visible light range by a high energy proton beam. The spatial photon density being proportional to that of the proton beam the analysis of the emitted image by a dedicated camera gives an accurate representation of the beam profiles. Based on these properties a non-interceptive detector has been developed and installed at CERN SPS proton synchrotron in order to measure the profile of the circulating beam. The results show that for an energy higher than 250 GeV and a beam intensity of at least 0.7 mA (1011 p) the results are satisfactory. The spatial resolution being 100 μm many beam parameters can be evaluated with good accuracy. (Auth.)