New probe of M1 and E1 strengths in GDR regions

Journal Article · Fri May 02 00:00:00 EDT 2014 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4874090· OSTI ID:22280481

Hayakawa, T. ^[1]; Ogata, K. ^[2]; Miyamoto, S.; Mochizuki, T.; Horikawa, K.; Amano, S. ^[3]; Imazaki, K.; Li, D.; Izawa, Y. ^[4]; Chiba, S. ^[5]

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1. Japan Atomic Energy Agency and National Astronomical Observatory in Japan (Japan)
2. RCNP, Osaka University (Japan)
3. University of Hyogo (Japan)
4. Institute for Laser Technology (Japan)
5. Tokyo Institute of Technology (Japan)

The M1 strengths (or level density of 1{sup +} states) are of importance for estimation of interaction strengths between neutrinos and nuclei for the study of the supernova neutrino-process. In 1957, Agodi predicted theoretically angular distribution of neutrons emitted from states excited via dipole transitions with linearly polarized gamma-ray beam at the polar angle of θ=90° should be followed by a simple function, a + b cos(2φ), where φ, is azimuthal angel. However, this theoretical prediction has not been verified over the wide mass region except for light nuclei as deuteron. We have measured neutron angular distributions with (polarized gamma, n) reactions on Au, Nal, and Cu. We have verified the Agodi's prediction for the first time over the wide mass region. This suggests that (polarized gamma, n) reactions may be useful tools to study M1 strengths in giant resonance regions.

• OSTI ID: 22280481
• Journal Information: AIP Conference Proceedings, Vol. 1594, Issue 1; Conference: OMEG12: 12. international symposium on origin of matter and evolution of galaxies, Tsukuba (Japan), 18-21 Nov 2013; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ANGULAR DISTRIBUTION
ASTROPHYSICS
COPPER 63 TARGET
COSMIC NEUTRONS
E1-TRANSITIONS
ENERGY-LEVEL DENSITY
GAMMA RADIATION
GIANT RESONANCE
GOLD 197 TARGET
LIGHT NUCLEI
M1-TRANSITIONS
NEUTRINO REACTIONS
NEUTRINOS
NEUTRON EMISSION
OSCILLATOR STRENGTHS
POLARIZATION
SUPERNOVAE