The HERMES Polarized Atomic Beam Source
- University of Erlangen - Nuernberg, E. Rommel - Str. 1, 91058 Erlangen (Germany)
The atomic beam source (ABS) provides nuclear polarized hydrogen or deuterium atoms for the HERMES target at flow rates of about 6.5 {center_dot} 1016H-vector/s (hydrogen in two hyperfine substates) and 6.0 {center_dot} 1016D-vector/s (deuterium in three hyperfine substates). The degree of dissociation of 93% for H (95% for D) at the entrance of the storage cell and the nuclear polarization of around 0.97 (H) and 0.92 (D) have been found to be constant within a a couple of percent over the whole running period of the HERMES experiment. A new dissociator (MWD) based on a microwave discharge at 2.45 GHz has been developed and installed into the HERMES-ABS in 2000. Since the velocity distribution of the MWD differs from that of the RFD the intensity could be increased further with a modified sextupole magnet system. For this purpose the way for a new start generator for sextupole tracking calculations was opened. Monte-Carlo simulations were successfully used to describe the gas expansion between nozzle, skimmer and collimator. A new type of beam monitor was used to study the beam formation after the nozzle.
- OSTI ID:
- 20625579
- Journal Information:
- AIP Conference Proceedings, Vol. 675, Issue 1; Conference: SPIN 2002: 15. international spin physics symposium and workshop on polarized electron sources and polarimeters, Upton, NY (United States), 9-14 Sep 2002; Other Information: DOI: 10.1063/1.1607271; (c) 2003 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); HERMES Target Group; ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ATOMIC BEAM SOURCES
BEAM FOCUSING MAGNETS
BEAM MONITORS
BEAM OPTICS
COMPUTERIZED SIMULATION
DEEP INELASTIC SCATTERING
DEUTERIUM
DEUTERIUM IONS
GHZ RANGE
HIGH-FREQUENCY DISCHARGES
HYDROGEN
MONTE CARLO METHOD
POLARIMETRY
POLARIZATION
POLARIZED BEAMS
POLARIZED TARGETS