Lifetime measurement of the 6.79 MeV state in {sup 15}O with the AGATA demonstrator

Journal Article · Mon Nov 12 00:00:00 EST 2012 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4763408· OSTI ID:22075757

Michelagnoli, C; Depalo, R; Ur, C A; Menegazzo, R; Broggini, C; Bazzacco, D; Caciolli, A; Farnea, E; Lunardi, S; Bemmerer, D; Keeley, N; Erhard, M; Fueloep, Zs; Gottardo, A; Marta, M; Mengoni, D; Mijatovic, T; Recchia, F; Rossi-Alvarez, C; Szuecs, T ^[1] ; others, and

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1. Dipartimento di Fisica e Astronomia Galileo Galilei, Universita di Padova (Italy) and INFN Padova (Italy)

The preliminary results of a new direct measurement of the lifetime of the first excited 3/2{sup +} state in {sup 15}O are discussed. An accurate evaluation of this lifetime is of paramount importance for the determination of the cross section of the {sup 14}N(p,{gamma}){sup 15}O reaction, the slowest one in the CNO cycle, at the energies of the solar Gamow peak. The {sup 2}H({sup 14}N,{sup 15}O)n reaction in inverse kinematics at 32MeV beam energy (XTU Tandem, LNL) was used to populate the level of interest, which decays via a 6.79 MeV E1 gamma-ray transition to the ground state. Gamma rays were detected with 4 triple clusters of HPGe detectors of the AGATA Demonstrator array. The energy resolution and position sensitivity of this state-of-the-art gamma-ray spectrometer have been exploited to investigate the Doppler Shift Attenuation effect on the lineshape of the gamma-ray peak in the energy spectrum. The deconvolution of the lifetime effects from those due to the kinematics of the emitting nuclei has been performed using detailed Monte Carlo simulations of the gamma emission and detection. CDCC-CRC calculations for the nucleon transfer process have been used for this purpose and preliminary results are shown.

• OSTI ID: 22075757
• Journal Information: AIP Conference Proceedings, Vol. 1484, Issue 1; Conference: Conference on origin of matter and evolution of galaxies 2011, Wako (Japan), 14-17 Nov 2011; Other Information: (c) 2012 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
CNO CYCLE
COMPUTERIZED SIMULATION
CROSS SECTIONS
DOPPLER EFFECT
ENERGY RESOLUTION
ENERGY SPECTRA
GAMMA DECAY
GAMMA RADIATION
GAMMA SPECTROMETERS
GAMMA SPECTROSCOPY
GROUND STATES
HIGH-PURITY GE DETECTORS
LIFETIME
MEV RANGE
MONTE CARLO METHOD
NITROGEN 14
OXYGEN 15
PROTON REACTIONS
PROTON-NUCLEON INTERACTIONS