First results from HECTOR: High EffiCiency TOtal absorption spectrometeR for p-process nucleosynthesis studies

The p-process is a nucleosynthesis scenario that occurs during an explosion of a supernova that produces proton-rich isotopes of elements between Se and Hg. The p-process involves series of ($\gamma$,n), ($\gamma$,p) and ($\gamma$,$\alpha$) reactions on pre-existing s-process seed nuclei. The reactions relevant for the p-process can be studied in the laboratory via the inverse ones: the capture of protons or $\alpha$-particles. For these measurements, the High EffiCiency 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 ($\alpha$,$\gamma$). The first measurements of the (p,$\gamma$) and ($\alpha$,$\gamma$) reactions on $^{102}$Pd and $^{90}$Zr isotopes will be presented in this talk. The results will be compared to the cross sections obtained with other techniques, when available, and to the Hauser-Feshbach model calculations using the Talys code.