Evidence for multiphonon giant resonances in electromagnetic fission of 238U.
Differential cross sections for electromagnetic fission of 238U projectiles (500 MeV/u) in C, Sn, and Pb targets are measured and analyzed in terms of single- and multiphonon giant resonance excitations as doorway states to fission. A novel experimental method exploits the linear relationship between neutron multiplicity and the primary 238U excitation energy. Multiphonon states contribute up to 20% of the cross section; a component at high excitation energies is indicated that may arise from three-phonon dipole and two-phonon GDR x GQRiv giant resonance excitations.
Ilievski
S
S
Institut für Kernphysik, Johann Wolfgang Goethe-Universität, D-60486 Frankfurt, Germany.
Aumann
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T
Boretzky
K
K
Elze
Th W
TW
Emling
H
H
Grünschloss
A
A
Holeczek
J
J
Holzmann
R
R
Kozhuharov
C
C
Kratz
J V
JV
Kulessa
R
R
Leistenschneider
A
A
Lubkiewicz
E
E
Ohtsuki
T
T
Reiter
P
P
Simon
H
H
Stelzer
K
K
Stroth
J
J
Sümmerer
K
K
Wajda
E
E
Waluś
W
W