Cross-section measurements of the ⁹⁴Mo(γ,n) and ⁹⁰Zr(γ,n) reactions using real photons at the HIγS facility

¹ Department of Physics and Astronomy, James Madison University, Harrisonburg, Virginia 22807, USA
² Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
³ University of North Carolina at Chapel Hill, North Carolina 27516, USA
⁴ Department of Physics, Duke University, Durham, North Carolina 27708, USA
⁵ University of Maryland Medical Center, Baltimore, Maryland 21201, USA

^* Corresponding author: banula@jmu.edu

Published online: 16 May 2018

Abstract

The photodisintegration reaction cross-sections for ⁹⁴Mo(γ,n) and ⁹⁰Zr(γ,n) have been experimentally investigated with quasi-monochromatic photon beams at the High Intensity γ-Ray Source (HIγS) facility, Triangle University Nuclear Laboratory (TUNL). The measurements were focused primarily on studying the energy dependence of the photoneutron cross sections, which is the most direct way of testing statistical models, and were performed close to the respective neutron thresholds and above up to ~ 20 MeV. Neutrons from the (γ,n) reactions were detected using a 4π assembly of ³He proportional counters developed at Los Alamos National Laboratory and presently available at TUNL. While the ⁹⁴Mo(γ,n) cross section measurement aims to contribute to a broader investigation for understanding the γ-process (the mechanism responsible for the nucleosynthesis of the so-called p-nuclei), the information from the ⁹⁰Zr(γ,n) data is relevant to constrain QRPA calculations of γ-ray strength functions in this mass region. In this contribution, we will present our preliminary results of the total (γ,n) excitation functions for the two photoneutron reactions on ⁹⁴Mo and ⁹⁰Zr.