Compton Scattering off Polarized Electrons with a High Finesse Fabry-Perot Cavity at JLAB
We built and commissioned a new type of Compton polarimeter to measure the electron beam polarization at the Thomas Jefferson National Accelerator Facility (Virginia, USA). The heart of this polarimeter is a high-finesse monolithic Fabry-Perot cavity. Its purpose is to amplify a primary 300 mW laser beam in order to improve the signal to noise ratio of the polarimeter. It is the first time that a high-finesse Fabry-Perot cavity is enclosed in the vacuum of a particle accelerator to monitor the beam polarization by Compton polarimetry. The measured finesse and amplification gain of the cavity are F=26000 and G=7300. The electron beam crosses this high-power photon source at an angle of 23 mrad in the middle of the cavity where the photon beam power density is estimated to be 0.85MW/cm2. We have used this facility during the HAPPEX experiment (April-July 1999) and we give a preliminary measurement of Compton scattering asymmetry.
- Research Organization:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Organization:
- USDOE Office of Energy Research (ER) (US)
- DOE Contract Number:
- AC05-84ER40150
- OSTI ID:
- 804109
- Report Number(s):
- JLAB-PHY-01-43; DOE/ER/40150-2326; TRN: US0300620
- Journal Information:
- Nuclear Instruments and Methods A, Vol. 459, Issue 3; Other Information: Nucl.Instrum.Meth.A459:412-425,2001; PBD: 1 Aug 2000
- Country of Publication:
- United States
- Language:
- English
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