Isospin splitting of the giant dipole built on the isobaric analog state
We report the first observation of the isospin splitting of the giant dipole resonance built on the isobaric analog state. Three giant resonances were observed in (/pi//sup +/,/pi//sup -/) double charge exchange (at T/sub /pi// = 292 MeV) on /sup 56/Fe at excitation energies of 25.7, 30.0, and 33.5 MeV (Q = -31.4, -35.7, and -39.2 MeV). Angular distributions were measured for the resonances and each observed to have a dipole shape. The cross-section ratios of the resonances are in close agreement with simple isospin geometry arguments for an isovector excitation built on the isobaric analog state. The summed cross section agrees well with simple sequential-model calculations in which the intermediate states arise from single charge exchange to the isobaric analog state and to the giant dipole resonance. We identify the three resonances as the isospin members of the charge-exchange dipole built on the isobaric analog state.
- Research Organization:
- Ben-Gurion University of the Negev, Beer-Sheva 84105 Israel, University of Texas at Austin, Austin, Texas 78712, and University of Pennsylvania, Philadelphia, Pennsylvania 19104
- OSTI ID:
- 6645212
- Journal Information:
- Phys. Rev. C; (United States), Vol. 38:6
- Country of Publication:
- United States
- Language:
- English
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Giant dipole resonances built on isobaric analog states in pion double charge exchange
Experimental investigation of nuclear double giant resonances
Related Subjects
IRON 56 TARGET
PION PLUS REACTIONS
CHARGE EXCHANGE
DIPOLES
GIANT RESONANCE
ISOBARIC ANALOGS
ISOSPIN
MEV RANGE 100-1000
MISSING MASS
PIONS MINUS
BOSONS
CHARGED-PARTICLE REACTIONS
ELEMENTARY PARTICLES
ENERGY LEVELS
ENERGY RANGE
HADRON REACTIONS
HADRONS
MASS
MESON REACTIONS
MESONS
MEV RANGE
MULTIPOLES
NUCLEAR REACTIONS
PARTICLE PROPERTIES
PION REACTIONS
PIONS
PSEUDOSCALAR MESONS
RESONANCE
TARGETS
651520* - Nuclear Properties & Reactions
A=39-58
Experimental