New results of GERDA on the search for bosonic Super-WIMPs.

Calgaro S.
  Giovedì 15/09   15:00 - 18:30   Aula T - Caterina Scarpellini   III - Astrofisica   Presentazione
The GERmanium Detector Array (GERDA) experiment at the Laboratori Nazionali del Gran Sasso has searched for the $^{76}Ge$ neutrinoless double-beta decay. Using an array of enriched high-purity germanium diodes, GERDA combined an excellent energy resolution to an ultra-low background level. This helped to explore other rare phenomena as the interactions of bosonic superweakly interacting massive particles (super-WIMPs). GERDA has searched for these keV-scale dark matter candidates via their absorption by an electron of a germanium atom. In this study, we considered an additional process, $i.e.$, the Compton-like scattering, which is dominant for masses above $150 {keV/{c}^{2}}$. A binned Bayesian analysis was applied for masses in $[60;$ 2m_e] ${keV/{c}^{2}}$ to either detect or set a $90%$ C.I. upper limit on the type of interactions that can induce a Gaussian peak in the energy spectrum. By including the dark Compton scattering, which has not been used in any other super-WIMP search experiment, and using a larger dataset of $119.8 kg\ yr$ of total exposure, previous GERDA upper limits for pseudoscalar and vector super-WIMP couplings to electrons were improved.