Development of TES microcalorimeters for future x-ray missions

A program for developing TES microcalorimeters for contributions to future Italian X-ray astronomy missions is under course. Its main scientific goals are the spectroscopic study of extreme astrophysical objects, characterized by very large energy release over short time scale, in particular gamma-ray bursts and transient compact objects, and the study of the early and close-by Universe by using gamma-ray bursts as cosmological beacons. Presently, the energy resolution of our detector has been improved to about 6 eV at 6 keV, with rise-time of about 10 mu s and fall time of few hundreds of mu s. We are developing and studying the suitable absorbers for high count rate performances.