137Ba Double Gamma Decay Measurement with GAMMASPHERE E. Merchán, K. Moran, C.J. Lister, P. Chowdhury, E.A. McCutchan, J.P. Greene, S. Zhu, T. Lauritsen, M.P. Carpenter and R. Shearman EPJ Web of Conferences, 93 (2015) 01033 Published online: 28 May 2015 DOI: 10.1051/epjconf/20159301033