Gain layer degradation study after neutron and proton irradiations in Low Gain Avalanche Diodes

The high-luminosity upgrade of the ATLAS and CMS experiments includes dedicated sub-detectors to perform the time-stamping of minimum ionizing particles (MIPs). These detectors will be exposed up to fluences in the range of 1.5 - 2.5e15 neq/cm2 at the end of their lifetime and, Low Gain Avalanche Diode (LGAD) has been chosen as their baseline detection technology. To better understand the performance of LGAD detectors in these environments, a gain layer degradation study after neutron and proton irradiations up to a fluence of 1.5e15 neq/cm2 was performed. LGADs manufactured at Hamamatsu Photonics (HPK) and Centro Nacional de Microelectr\'onica (CNM-IMB) were chosen for this study and, a comparison in the gain layer degradation after exposure to reactor neutrons at the Jozef Stefan Institute (JSI) in Ljubjana and 24 GeV/c protons at the CERN-PS is presented here.