Design of the HERMES internal {sup 3}He target

Journal Article · Fri Oct 01 04:00:00 EDT 1993 · Bulletin of the American Physical Society

OSTI ID:387147

Kramer, L H; Deschepper, D; Kelsey, J M; Milner, R M

An internal polarized {sup 3}He target is currently under construction at MIT. The target will be used in the HERMES experiment, which will measure the spin dependent deep inelastic scattering from the neutron and proton by the scattering of 30-35 GeV longitudinally polarized electrons from polarized hydrogen, deuterium, and {sup 3}He in the East Hall of HERA. The target is based on the technique of metastability exchange laser optical pumping. {sup 3}He nuclei are introduced into a glass cell, where they are polarized with high intensity laser light. The nuclei then migrate out of the glass cell into a windowless storage cell where they are allowed to interact with the beam before being pumped away. Two pairs of Helmholtz coils will be employed to create a magnetic field which will orient the {sup 3}He nuclei along one of two axes. The storage cell will be cryogenically cooled to 15K, giving a density of 10{sup 15} atoms/cm{sup 2}. Target polarizations of over 50% are expected. The present status of the HERMES target will be discussed.

• OSTI ID: 387147
• Report Number(s): CONF-931044--
• Journal Information: Bulletin of the American Physical Society, Journal Name: Bulletin of the American Physical Society Journal Issue: 9 Vol. 38; ISSN BAPSA6; ISSN 0003-0503
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
66 PHYSICS
DEEP INELASTIC SCATTERING
DESIGN
ELECTRON REACTIONS
HELIUM 3 TARGET
POLARIZED TARGETS