2 νββ. 0 νββ. Prompt Region. True Coincidences. Background Region. Gammas. Random Coincidences. n beam. d + beam. 2 H(d,n) 3 He. Beam pick-off. 4 atm. 214 Bi. 0 νββ ?. Triangle Universities Nuclear Laboratory.
Triangle Universities Nuclear Laboratory
Precision cross section measurement of Cu at 8 and 12 MeV for background reduction in the next generation of 0νßß decay experiments*
M.A. Antonacci1, A. Chyzh2, J. Esterline3, S. Elliott4, B. Fallin3, A. Hime4, C.R. Howell3, A Hutcheson3, H.J. Karwowski5, J.H. Kelley2, M. Kidd3, D. Mei4, B. Spaun6, A.P. Tonchev3, W. Tornow3
1 Saint Vincent College, 2 North Carolina State University and TUNL, 3 Duke University and TUNL, 4 Los Alamos National Laboratory, 5 University of North Carolina at Chapel Hill, 6 Whitworth College
Analysis and Results
A Proposed Majorana Setup
Renewed interest in observing 0nbb decay reactions has sparked efforts to experimentally verify the existence of such decays, and observe new physics beyond the Standard Model. These reactions, with half-lives around 1027 years, require an extensive understanding of background sources. The potential for neutron induced excitation of the shielding and detector materials is important for understanding and designing future 0nbbdecay experiments. Gamma transitions at 2041, 2615, and 3062 keV directly obscure 0nbbdecay detection of 76Ge at 2040 keV. Due to lack of experimental information in the nuclear database, high-resolution g-ray spectra from the interaction of mono-energetic and pulsed neutrons were measured at TUNL. The emitted g-rays were detected with 3 HPGe segmented clover detectors at 62°, 90°, and 135°. From these data, partial cross-sections for prominent g transitions in 63,65Cu were derived at En = 8 and 12 MeV. This experimental information will also help to understand the existing 0nbbdata and serve as a benchmark for statistical model calculations.
Motivation: The Majorana Project
In Search of 0νββ
(A,Z) (A,Z+2) + 2e- + 2ν
(A,Z) (A,Z+2) + 2e-
10MV FN Tandem
Observed Partial Cross-sections
DENIS II negative
*only 20% of
*Supported in part by DOE grant DE-FG02-97ER41033 (Duke) and NSF grant NSF-05-52723.
1H.V. Klapdor-Kleingrothaus et al., Phys. Lett. B 586 (2004) 198