Speaker
Description
The $\gamma$-process is a nucleosynthesis scenario that occurs during an explosion of a supernova and produces the proton-rich isotopes of elements between Se and Hg. The $\gamma$-process involves series of ($\gamma$,n), ($\gamma$,p) and ($\gamma$,$\alpha$) reactions on pre-existing s-process seed nuclei. The reactions relevant for the $\gamma$-process can be studied in the laboratory via the inverse ones: the capture of protons or $\alpha$-particles. For these measurements, the High EffCiency TOtal Absorption SpectrometeR (HECTOR) was developed at the University of Notre Dame.
HECTOR is a NaI(Tl) summing detector comprised of 16 separate NaI(Tl) crystals, each read by 2 photomultipliers. The array is designed for precision cross section measurements for (p,$\gamma$) and ($\alpha$,$\gamma$) reactions across the $\gamma$-process Gamow window. The summing efficiency is a function of the total $\gamma$-ray energy and the average $\gamma$-ray multiplicity: for the $^{60}$Co, source it is 52.7 (2.0)% and for typical cross section measurements it ranges between 20-30%.
Here, an overview of the recent results obtained with HECTOR for A~100 mass region will be presented. The experimental data will be compared to the Hauser-Feshbach model calculations using the Talys code and will be used to constrain the inputs for Talys to best reproduce the experimental data in the A~100 mass region.
This work is supported by the NSF under grants number: PHY-1614442,
and PHY-2011890.
