Transition-Edge Sensors for HOLMES

HOLMES is an experiment aiming at performing a direct measurement of the neutrino mass from the electron capture (EC) spectrum of \(^{163}\hbox {Ho}\). In order to reach a sensitivity of the order of \(\sim \)1 eV/c\(^2\) on the neutrino mass, it is necessary to gather as many as \(10^{13}\) events in the 3-year projected live time of HOLMES, keeping the pileup fraction as low as \(10^{-4}\). This is not a trivial matter when it comes to low- temperature calorimeters, which usually have a rather slow time response. At the same time, a large number of detectors need to be operated simultaneously, and hence, in order to avoid an extremely large cryogenic facility, multiplexing is required. In this contribution, I will outline the current status and perspective of HOLMES, with special care devoted to the detectors and readout system, which have currently reached their target performance.