Spin and Parity Assignment of Neutron Resonances using Gamma-ray Multiplicity

Journal Article · Tue Mar 31 00:00:00 EDT 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3122240· OSTI ID:21293502

Agvaanluvsan, U ^[1]; Mitchell, G E ^[2]; Baramsai, B; Chyzh, A; Walker, C ^[2]; Dashdorj, D ^[3]; Becker, J A; Parker, W E; Sleaford, B; Wu, C Y ^[4]; Bredeweg, T A; Couture, A; Haight, R C; Jandel, M; Rundberg, R S; Ullmann, J L; Vieira, D J; Wouters, J M ^[5]; Krticka, M; Becvar, F ^[6]

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1. Stanford University, Palo Alto, CA 94305 (United States)
2. North Carolina State University, Raleigh, NC 27695 (United States)
3. MonAme Scientific Research Center, Ulaanbaatar (Mongolia)
4. Lawrence Livermore National Laboratory, Livermore, CA 9455 (United States)
5. Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)
6. Charles University in Prague, CZ-180 00 Prague 8 (Czech Republic)

Decay gamma rays following neutron capture on various isotopes are collected by the Detector for Advanced Neutron Capture Experiments (DANCE) array, which is located at flight path 14 at the Lujan Neutron Scattering Center at Los Alamos National Laboratory. The high segmentation (160 detectors) and close packing of the detector array enable gamma-ray multiplicity measurements. The calorimetric properties of the DANCE array coupled with the neutron time-of-flight technique enables one to gate on a specific resonance of a given isotope in the time-of-flight spectrum and obtain the summed energy spectrum for that isotope. The singles gamma-ray spectrum for each multiplicity can be separated by their DANCE cluster multiplicity. The multiplicity distribution contains the signatures of spin and parity of the capture state. Under suitable circumstances where the difference between spins of the initial (capture) and final (ground) state is large enough, the signatures in the multiplicity distribution can be used in improving the spin assignment of the initial state. The spin assignment is applied with varying degree of success to difference isotopes and description of this application for {sup 95}Mo, {sup 151,153}Eu, and {sup 155,157}Gd is reviewed briefly.

• OSTI ID: 21293502
• Journal Information: AIP Conference Proceedings, Vol. 1109, Issue 1; Conference: 1. Ulaanbaatar conference on nuclear physics and applications, Ulaanbaatar (Mongolia), 8-11 Sep 2008; Other Information: DOI: 10.1063/1.3122240; (c) 2009 American Institute of Physics; 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
CAPTURE
EUROPIUM 153
GADOLINIUM 157
GAMMA DECAY
GAMMA RADIATION
GAMMA SPECTRA
GROUND STATES
LANL
MOLYBDENUM 95
MULTIPLICITY
NEUTRON REACTIONS
NEUTRONS
PARITY
RESONANCE
SPIN
TIME-OF-FLIGHT METHOD