{gamma}-ray strength function for {sup 116,117}Sn with the pygmy dipole resonance balanced in the photoneutron and neutron capture channels

Journal Article · Sun Nov 15 04:00:00 EST 2009 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.80.055806· OSTI ID:21296544

Utsunomiya, H; Kamata, M; Kondo, T; Itoh, O; Akimune, H; Yamagata, T ^[1]; Goriely, S ^[2]; Toyokawa, H ^[3]; Lui, Y -W ^[4]; Hilaire, S ^[5]; Koning, A J ^[6]

---

1. Department of Physics, Konan University, Okamoto 8-9-1, Higashinada, Kobe 658-8501 (Japan)
2. Institut d'Astronomie et d'Astrophysique, Universite Libre de Bruxelles, Campus de la Plaine, CP-226, Brussels B-1050 (Belgium)
3. National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8568 (Japan)
4. Cyclotron Institute, Texas A and M University, College Station, Texas 77843 (United States)
5. CEA, DAM, DIF, Arpajon F-91297 (France)
6. Nuclear Research and Consultancy Group, Post Office Box 25, ZG Petten NL-1755 (Netherlands)

Photoneutron cross sections were measured for {sup 117}Sn and {sup 116}Sn near the neutron thresholds at 6.94 and 9.56 MeV, respectively, with quasi-monochromatic laser-Compton scattering {gamma} rays. The {sup 117}Sn cross section, which is strongly enhanced near the low threshold, provides evidence for the presence of extra {gamma} strength in the low-energy tail of the giant dipole resonance. A coherent analysis of the photoneutron data for {sup 117}Sn together with the neutron capture on {sup 116}Sn shows that the {gamma}-ray strength function is balanced in the photoneutron and neutron capture channels in terms of the microscopic Hartree-Fock-Bogoliubov plus quasiparticle random-phase approximation model of E1 strength combined with a pygmy E1 resonance at 8.5 MeV. The high-energy part of the pygmy resonance is also suggested in the photoneutron cross section for {sup 116}Sn.

• OSTI ID: 21296544
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 5 Vol. 80; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
CAPTURE
COMPTON EFFECT
CROSS SECTIONS
DIPOLES
E1-TRANSITIONS
GAMMA RADIATION
HARTREE-FOCK-BOGOLYUBOV THEORY
MEV RANGE 01-10
MONOCHROMATIC RADIATION
NEUTRON REACTIONS
NEUTRONS
RANDOM PHASE APPROXIMATION
RESONANCE
STRENGTH FUNCTIONS
TIN 116
TIN 117