Two-nucleon processes in pion-induced double charge exchange in {sup 4}He: A coincidence measurement of the {sup 4}He({pi}{sup +},{pi}{sup {minus}} {ital p})3{ital p} reaction

Journal Article · Wed May 10 00:00:00 EDT 1995 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.48148· OSTI ID:244481

Pate, S F; Fong, W; Harvey, M T; Matthews, J L; Park, H T; Vidos, L L; Zelevinsky, V V ^[1]; Saunders, A; Holcomb, M D; Kinney, E R; Kriss, B J ^[2]; Gram, P A.M. ^[3]; Roberts, D A ^[4]

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1. Laboratory for Nuclear Science, MIT, Cambridge, Massachusetts 02139 (United States)
2. Department of Physics, University of Colorado, Boulder, Colorado 80309 (United States)
3. Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
4. Department of Physics, University of Michigan, Ann Arbor, Michigan 48109 (United States)

Inclusive measurements of pion double-charge-exchange in {sup 3}He[1] and {sup 4}He[2] in the {Delta}(1232) resonance region suggest the dominance of a two-step sequential single-charge-exchange mechanism involving quasi-free nucleons. To investigate this reaction mechanism, we have observed protons in coincidence with the outgoing pion in {pi}{sup +}+{sup 4}He{r_arrow}{pi}{sup {minus}}+4{ital p} at {ital T}{sub {pi}{sup +}}=240 MeV. Pions were detected in a magnetic spectrometer at {theta}{sub {pi}{sup {minus}}}=32{degree}, while protons were detected in a close-packed array of plastic scintillator telescopes covering {theta}{sub {ital p}}=67.5{degree}--157.5{degree} on the same side of the beam as the spectrometer, and {theta}{sub {ital p}}=22.5{degree}--157.5{degree} on the opposite side. We will present preliminary results for the distributions in energy and angle of the coincident protons. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

• Sponsoring Organization: USDOE
• OSTI ID: 244481
• Report Number(s): CONF-9405132-; ISSN 0094-243X; TRN: 96:012934
• Journal Information: AIP Conference Proceedings, Vol. 334, Issue 1; Conference: 14. International IUPAP conference on few body problems in physics, Williamsburg, VA (United States), 26-31 May 1994; Other Information: PBD: 10 May 1995
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
HELIUM 4 TARGET
PION PLUS REACTIONS
CHARGE-EXCHANGE REACTIONS
N*BARYONS
PROTONS
COINCIDENCE METHODS
DIFFERENTIAL CROSS SECTIONS
MEV RANGE 100-1000
EXPERIMENTAL DATA