Pion absorption by sup 3 He at the. Delta. -resonance energy

Journal Article · Fri Mar 01 04:00:00 EST 1991 · Physical Review, C (Nuclear Physics); (USA)

DOI:https://doi.org/10.1103/PhysRevC.43.957· OSTI ID:6395281

Mukhopadhyay, S; Levenson, S; Segel, R E; Garino, G ^[1]; Geesaman, D; Schiffer, J P; Stephans, G; Zeidman, B; Ungricht, E; Jackson, H; Kowalczyk, R ^[2]; Ashery, D; Piasetsky, E; Moinester, M; Navon, I ^[3]; Smith, L C; Minehart, R C; Das, G S; Whitney, R R ^[4]; Mckeown, R ^[5] ; Anderson, B; Madey, R; Watson, J ^[6]

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1. Northwestern University, Evanston, Illinois (US)
2. Argonne National Laboratory, Argonne, Illinois (US). Physics Division
3. Tel-Aviv University, Ramat Aviv, Israel (IL). Department of Physics
4. University of Virginia, Charlottesville, Virginia (US). Department of Physics
5. California Institute of Technology, Pasadena, California (US). Department of Physics
6. Kent State University, Kent, Ohio (US)

Pion absorption by {sup 3}He was studied at {ital T}{sub {pi}}=165 MeV in a kinematically complete experiment. The cross section for absorption on a ({ital pn}) pair of nucleons, {sigma}{sub {ital p}{ital n}}({pi}{sup +}), was found to be 17.0{plus minus}2.6 mb; that for absorption on a ({ital pp}) pair, {sigma}{sub {ital p}{ital p}}({pi}{sup {minus}}), 0.91{plus minus}0.20 mb. The angular distribution in the {pi}{ital NN} center-of-mass system for {sigma}{sub {ital p}{ital n}}({pi}{sup +}) resembles that for the {pi}{sup +}+{ital d}{r arrow}{ital p}+{ital p} reaction while the angular distribution for {sigma}{sub {ital p}{ital p}}({pi}{sup {minus}}) is strongly backward peaked. Evidence that a significant fraction of the absorptions involves all three target nucleons is seen in the angular correlation between the two detected nucleons as well as in the momentum distribution of the unobserved nucleon. For {pi}{sup +} and {pi}{sup {minus}} absorption, the three-body cross sections were found to be 9.6{plus minus}2.1 and 4.2{plus minus}01.2 mb, respectively. Neither initial- nor final-state interactions appear to be major contributors to the observed three-body absorption, though initial-state interactions may be contributing to the enhancement of the three-body {pi}{sup +} absorption at the {Delta} resonance.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• DOE Contract Number: W-31109-ENG-38; AS05-76ER04043
• OSTI ID: 6395281
• Journal Information: Physical Review, C (Nuclear Physics); (USA), Journal Name: Physical Review, C (Nuclear Physics); (USA) Vol. 43:3; ISSN 0556-2813; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

651220* -- Nuclear Properties & Reactions
A=1-5
Experimental
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ACCELERATORS
ANGULAR DISTRIBUTION
BARYON-BARYON INTERACTIONS
BARYONS
CAPTURE
CHARGED-PARTICLE REACTIONS
CROSS SECTIONS
DELTA BARYONS
DELTA-1232 BARYONS
DISTRIBUTION
ELEMENTARY PARTICLES
ENERGY RANGE
FERMIONS
HADRON REACTIONS
HADRON-HADRON INTERACTIONS
HADRONS
HELIUM 3 TARGET
INTERACTIONS
IONIZATION CHAMBERS
LAMPF LINAC
LINEAR ACCELERATORS
MANY-BODY PROBLEM
MEASURING INSTRUMENTS
MESON FACTORIES
MESON REACTIONS
MEV RANGE
MEV RANGE 100-1000
N BARYONS
NUCLEAR REACTIONS
NUCLEON-NUCLEON INTERACTIONS
PARTICLE INTERACTIONS
PION MINUS REACTIONS
PION PLUS REACTIONS
PION REACTIONS
RADIATION DETECTORS
SCINTILLATION COUNTERS
TARGETS
THREE-BODY PROBLEM