Service:
- Member Representative to Associated Universities for Research in Astronomy (AURA)Â Board, 2010-present
- Associate and Senior Editor, IEEE Transactions on Nuclear Science, 2005-present
- Associate Editor, Journal of Crystal Growth, 2009-present
- During 2006-09 I was elected and served as Vice Chair, Chair and Immediate Past Chair of the Fisk University Faculty Assembly and as Faculty Member of the Fisk University Board of Trustees, 2007-08
- Co-chair, Annual International Conference on Hard X-Ray and Gamma-Ray Detector Physics, 2003-presentÂ
- Co-chair, Materials Research Society (MRS) Symposium on Nuclear Radiation Detection Materials, 2007, 2009
- Member of  the SPIE’s Engineering, Science and Technology Policy (ESTeP) Committee, 2007
- Chairman of the Steering Committee of the SPIE International Technical Group on Penetrating Radiation, 1999-2000