Channeling Studies with Electron and Positron Beams with Bent and Undulator Crystals at SLAC

by Uli Wienands (SLAC)

Thursday 27 Nov 2014, 15:30 → 16:45 Europe/Zurich

4/3-006 - TH Conference Room (CERN)

Channeling in bent crystals is effective for deflection of high-energy particle beams, esp. protons. The process has enjoyed increased interest in particular due to the beam-collimation activities at CERN (UA9) and at the Tevatron (T-980). There is however very little channeling data in existence for high-energy electron or positron beams. At SLAC, an Aarhus-Ferrara-CalPoly-SLAC collaboration has conducted a channeling experiment (T-513) in the End Station A Test Beam to quantify channeling and volume-reflection effects using a thin, bent silicon crystal with 400 µr bending angle. Significant channeling rates were found, and volume reflection proved to be quite an efficient process with a deflection of the beam by about 100 µrad. Surface transmission and dechanneling rates can be extracted and compared to expectation, providing insight into the physics involved. Very recently, E212 had its first run with an Aarhus-built 10-period undulator crystal in the 20 GeV positron beam at FACET. The experiments point the way towards possible arrangements for collimation of lepton beams e.g. in a linear collider as well as the possibility of crystal undulators in order to produce narrow-band gamma rays.

 

ATS Seminars Organisers: H. Burkhardt (BE), M. Modena (TE), T. Stora (EN)


Coffee / tea will be served after the seminar in front of TH conference room.
 

Presentation Channeling_CERN_Nov_2014.pdf