Background

Andrew Ratkiewicz completed his postgraduate study at the National Superconducting Cyclotron Laboratory at Michigan State University, where he measured the evolution of collectivity in exotic isotopes of silicon and the collapse of the N=28 magic number. After graduating with his PhD, he moved to Oak Ridge National Lab, where he worked as a postdoc for Rutgers University to combine the Oak Ridge Rutgers University Barrel Array (ORRUBA) and GAMMASPHERE as a large-scale particle-gamma spectrometer. Andrew joined LLNL as a postdoctoral research staff member in 2015 and became a staff member in 2017. His research interests include nuclear astrophysics, where he has done work to develop indirect methods to probe neutron-induced reactions and to probe the strength of the interaction between nuclei and plasmas, neutron imaging—specifically the development of detectors and techniques to image objects with fast neutrons—and calculations of neutron transport focusing on the impact of uncertainties in nuclear data on the calculations.

Ph.D., Physics, Michigan State University, 2011

B.S., Physics, Indiana University South Bend, 2006

M.R. Hall, D.W. Bardayan, T. Baugher, A. Lepailleur, S.D. Pain, A. Ratkiewicz, S. Ahn, J.M. Allen, J.T. Anderson, A.D. Ayangeakaa, et al., “γ-ray spectroscopy of astrophysically important states in ³⁹Ca” (2020) Phys. Rev. C (101), 015804.

M.R. Hall, D.W. Bardayan, T. Baugher, A. Lepailleur, S.D. Pain, A. Ratkiewicz, S. Ahn, J.M. Allen, J.T. Anderson, A.D. Ayangeakaa, et al., “Key ¹⁹Ne States Identified Affecting γ-Ray Emission from 18F in Novae” (2019) Phys. Rev. Lett. (122), 052701.

A. Ratkiewicz, J.A. Cizewski, J.E. Escher, G. Potel, J.T. Burke, R.J. Casperson, M. McCleskey, R.A.E. Austin, S. Burcher, R.O. Hughes, et al. (2019), “Towards Neutron Capture on Exotic Nuclei: Demonstrating (d,pγ) as a Surrogate Reaction for (n,γ)” Phys. Rev. Lett. (122), 052502.

J.A. Cizewski and A. Ratkiewicz (2018) "Neutron Capture on Short-Lived Nuclei via the Surrogate (d,pγ) Reaction" EPJ Web of Conferences (178), 03003.

S.D. Pain, A. Ratkiewicz, T. Baugher, M. Febbraro, A. Lepailleur, A.D. Ayangeakaa, J. Allen, J.T. Anderson, D.W. Bardayan, J.C. Blackmon, R. Blanchard, et al. (2017), “Direct Reaction Measurements Using GODDESS” Physics Procedia (90), 455-462.

A. Ratkiewicz, J.A. Cizewski, S.D. Pain, A.S. Adekola, J.T. Burke, R.J. Casperson, N. Fotiades, M. McCleskey, S. Burcher, C.M. Shand, et al., (2015) "Validating (d,pγ) as a Surrogate for Neutron Capture" EPJ Web of Conferences (93), 02012.

R.J. Casperson, J.T. Burke, N.D. Scielzo, J.E. Escher, E. McCleskey, M. McCleskey, A. Saastamoinen, A. Spiridon, A. Ratkiewicz, A. Blanc, M. Kurokawa, and R.G. Pizzone, (2014) "Measurement of the ²⁴⁰Am(n,f) cross section using the surrogate-ratio method" Phys. Rev. C (90), 034601.

A. Ratkiewicz, S.D. Pain, J.A. Cizewski, D.W. Bardayan, J.C. Blackmon, K.A. Chipps, S. Hardy, K.L. Jones, R.L. Kozub, C.J. Lister, et al. (2013), “Coupling Gammasphere and ORRUBA.” AIP Conference Proceedings (1525), 487-491.