Double beta decay of Ge-76 into excited states of Se-76 in Gerda

Gerda is an experiment searching for the neutrinoless double beta (0$\nu \beta \beta$) decay of ${}^{76}$Ge. The observation of such a decay would prove the Majorana character of the neutrino, i.e. that it is its own antiparticle. This could shed light upon the neutrino mass ordering realized in nature as well as the effective Majorana neutrino mass. The half life of the neutrino accompanied double beta (2$\nu \beta \beta$) decay from the 0${}^{+}$ ground state of ${}^{76}$Ge into the 0${}^{+}$ ground state of ${}^{76}$Se has been measured by Gerda with unprecedented precision. Furthermore, ${}^{76}$Ge can decay into excited states of ${}^{76}$Se, though these transitions are phase space suppressed. Theoretical calculations predict the half lives of these decays, but the results vary by several orders of magnitude due to different nuclear models and their internal parameters. The observation of the 2$\nu \beta \beta$ decay of ${}^{76}$Ge into excited states could constrain these models and decrease their uncertainties. Moreover, models of the 0$\nu \beta \beta$ decay, that rely on similar assumptions, would be improved. The excited states analysis of the Gerda data is performed by counting coincident events within the Germanium detector array and optimized with the help of Monte Carlo simulations. The talk will present the analysis technique and preliminary results of the current Gerda Phase II data.