Hope College Department of Physics and Engineering Research Experiences for Undergraduates Summer 2006 Project Summary

Data were collected on the breakup of the unstable ⁷He nucleus into ⁶He and a neutron, and the decay energy of ⁷He was calculated. The experiment was designed to verify the experimental setup and methods as well as detector resolution by confirming the currently-accepted ⁷ He decay energy of 435 keV. ¹ A ⁸Li beam impinged upon a beryllium target, producing short-lived ⁷He nuclei. The decay products were detected and the decay energy of each ⁷He was determined to be approximately 370 keV. While this does not match the accepted value of 435 keV ¹ , a recent publication has tentatively suggested a possible lower value of 360 keV. ² Further analysis is in progress to verify this result and to determine uncertainty.

*This material is based upon work supported by the National Science Foundation under NSF-REU Grant No. 0452206

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Publications and Presentations:
"Production of Nuclei in Neutron Unbound States via Primary Fragmentation of ⁴⁸Ca", G. Christian, W.A. Peters, D. Absalon*, D. Albertson*, T. Baumann, D. Bazin, E. BreitbachI, J. Brown, P.L. Cole*, D. Denby*, P.A. DeYoung, J.E. Finck, H. Frank, A. Fritsch*, C. Hall*, A.M. Hayes, J. Hinnefeld, C.R. Hoffman, R. Howes, B. Luther, E. Mosby*, S. Mosby*, D. Padilla*, P.V. Pancella, G. Peaslee, W.F. Rogers, A. Schiller, M.J. Strongman, M. Thoennessen, and L.O. Wagner*. Nucl. Phys. A801, 101, (2008)

" BaF Array for γ-tagged Studies with Radioactive Nuclear Beams", H. Amro, F.D. Becchetti, Hao Jing, M. Ojaruega, J.J. Kolata, B. Skorodumov, G. Peaslee, P. DeYoung, D. Denby*, and J.D. Hinnefeld. Nucl. Instr. and Meth. A579, 31, (2007).

^"7Be-Induced alpha-Transfer Reaction on ¹²C", H. Amro, F.D. Becchetti, Yu Chen, Hao Jiang, M. Ojaruega, M.J. Golobish, H.C. Griffin, J.J. Kolata, B. Skorodumov, G. Peaslee, P.A. DeYoung, P. Mears, D. Denby*, J. Brown, J.D. Hinnefeld, and A.M. Moro. Euro. Phys. Jour. bf 150, 1, (2007).

"Analysis of Kinematics and Decay Energy in the Breakup of ⁷He". Deborah Denby*, Paul A. DeYoung, Graham F. Peaslee, and the MoNA Collaboration. CEU session at the Division of Nuclear Physics of the APS meeting, Poster 3A.00022, Nashville, TN, October 2006.

G. Audi et al., Nucl. Phys. A729 , 337 (2003)

F. Skaza et al., Phys. Rev. C73 , 044301 (2000).