Experimental measurement of ${}_{91}\mathrm{Zr}$( $n,\gamma ){}_{92}\mathrm{Zr}$ at the CSNS Back-n facility from 0.82 keV to 229 keV

Zr isotopes are important nuclides on the $s$-process path, and their neutron capture cross sections are of great significance for studying the evolution of heavy nuclei in the universe. In this work, the cross section of the ${}_{91}\mathrm{Zr}(n,\gamma ){}_{92}\mathrm{Zr}$ reaction was measured at the China Spallation Neutron Source (CSNS) Back-n platform from 0.82 keV to 229 keV, essentially covering the energy range of astrophysical interest. In the experiment, a high-purity germanium detector with excellent energy resolution was used, which allowed for the accurate identification of characteristic $\gamma$ rays emitted during ${}_{92}\mathrm{Zr}$'s de-excitation, thereby enabling precise measurement of the neutron capture cross section. Furthermore, the measurement yielded the Maxwellian-averaged cross section of $56.4\pm 5.0$ mb calculated at $kT=30$ keV.