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Title: Electromagnetic dissociation of relativistic [sup 28]Si by nucleon emission

A detailed study of the electromagnetic dissociation of [sup 28]Si by nucleon emission at E[sub lab]/A = 14.6 (GeV/nucleon was carried out with [sup 28]Si beams interacting on [sup 208]Pb). [sup 120]Sn. [sup 64]C targets. The measurements apparatus consists of detectors in the target area which measure the energy and charged multiplicity, and a forward spectrometer which measures the position, momentum and energy of the reaction fragments. The exclusive electromagnetic dissociation cross sections for decay channels having multiple nucleons in the final state have been measured which enables the selection of events produced in pure electromagnetic interactions. The measured cross sections agree well with previous measurements obtained for the removal of a few nucleons as well as with measurements on total charge removal cross sections from other experiments. The dependence of the integrated cross sections on the target charge Z[sub T] and the target mass AT confirms that for higher Z targets the excitation is largely electromagnetic. Direct measurements of the excitation energy for the electromagnetic dissociation of [sup 28]Si [yields] p+[sup 27]Al and [sup 28]Si [yields] n+[sup 27]Si have been obtained through a calculation of the invariant mass in kinematically, reconstructed events. The excitation energy spectrum for all targetsmore » peak near the isovector giant dipole resonance in [sup 28]Si. These distributions are well reproduced by combining the photon spectrum calculated using the Weizsaecker-Williams approximation with the experimental data on the photonuclear [sup 28]Si([sub [gamma],p])[sup 27]Al and [sup 28]Si([sub [gamma],n])[sup 27]Si. The possibilities of observing double giant dipole resonance excitations in [sup 28]Si have been investigated with cross section measurements as well as with excitation energy reconstruction.« less
Authors:
Publication Date:
OSTI Identifier:
6610539
Report Number(s):
DOE/ER/40363-T3
ON: DE93008670
DOE Contract Number:
FG02-87ER40363
Resource Type:
Technical Report
Resource Relation:
Other Information: Thesis (Ph.D.)
Research Org:
Pittsburgh Univ., PA (United States)
Sponsoring Org:
DOE; USDOE, Washington, DC (United States)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ALUMINIUM 27 TARGET; SILICON 28 REACTIONS; CARBON 12 TARGET; COPPER 64 TARGET; LEAD 208 TARGET; COULOMB SCATTERING; TIN 120 TARGET; ALUMINIUM 27; CROSS SECTIONS; DISSOCIATION; EXPERIMENTAL DATA; GEV RANGE 100-1000; GIANT RESONANCE; NEUTRONS; PROTONS; RELATIVISTIC RANGE; SILICON 27; ALUMINIUM ISOTOPES; BARYONS; BASIC INTERACTIONS; BETA DECAY RADIOISOTOPES; BETA-PLUS DECAY RADIOISOTOPES; CHARGED-PARTICLE REACTIONS; DATA; ELASTIC SCATTERING; ELECTROMAGNETIC INTERACTIONS; ELEMENTARY PARTICLES; ENERGY RANGE; EVEN-ODD NUCLEI; FERMIONS; GEV RANGE; HADRONS; HEAVY ION REACTIONS; INFORMATION; INTERACTIONS; ISOTOPES; LIGHT NUCLEI; NUCLEAR REACTIONS; NUCLEI; NUCLEONS; NUMERICAL DATA; ODD-EVEN NUCLEI; RADIOISOTOPES; RESONANCE; SCATTERING; SECONDS LIVING RADIOISOTOPES; SILICON ISOTOPES; STABLE ISOTOPES; TARGETS 663450* -- Heavy-Ion-Induced Reactions & Scattering-- (1992-); 663530 -- Nuclear Mass Ranges-- A=20-38-- (1992-); 663520 -- Nuclear Mass Ranges-- A=6-19-- (1992-); 663550 -- Nuclear Mass Ranges-- A=59-89-- (1992-); 663560 -- Nuclear Mass Ranges-- A=90-149-- (1992-); 663580 -- Nuclear Mass Ranges-- A=190-219-- (1992-)