Validating (d,pγ) as a Surrogate for Neutron Capture

¹ Department of Physics and Astronomy, Rutgers University, New Brunswick, NJ 08903, USA
² Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
³ Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
⁴ Los Alamos National Laboratory, Los Alamos, NM 87545, USA
⁵ Cyclotron Institute, Texas A&M University, College Station, TX 77843, USA
⁶ Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH, UK
⁷ Astronomy and Physics Department, Saint Mary’s University, Halifax, NS BH3 3C3, Canada
⁸ Physics Division, Argonne National Laboratory, Argonne, IL 60439, USA
⁹ Department of Physics, University of Richmond, VA 23173, USA
¹⁰ Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, USA
¹¹ Physics Department, Tennessee Technological University, Cookeville, TN 38505, USA
¹² Department of Physics and Applied Physics, University of Massachusetts Lowell, Lowell, MA 01854, USA
¹³ Oak Ridge Associated Universities, Oak Ridge, Tennessee 37831, USA

^a email: a.ratkiewicz@rutgers.edu

Published online: 28 May 2015

Abstract

The r-process is responsible for creating roughly half of the elements heavier than iron. It has recently become understood that the rates at which neutron capture reactions proceed at late times in the r-process may dramatically affect the final abundance pattern. However, direct measurements of neutron capture reaction rates on exotic nuclei are exceptionally difficult, necessitating the development of indirect approaches such as the surrogate technique. The (d,pγ) reaction at low energies was identified as a promising surrogate for the (n,γ) reaction, as both reactions share many characteristics. We report on a program to validate (d,pγ) as a surrogate for (n,γ) using ⁹⁵Mo as a target. The experimental campaign includes direct measurements of the γ-ray intensities from the decay of excited states populated in the ⁹⁵Mo(n,γ) and ⁹⁵Mo(d,pγ) reactions.