One of the processes that are mostly exploited in particle detection is scintillation, whereby light in transparent media (organic or inorganic materials, including salts, gases, and liquids) is emitted following the absorption of ionising radiation. Scintillation is the result of a spontaneous decay, with relatively slow fluorescence decay time and isotropic emission. In this project we want to explore experimentally the possibility to realise a completely new concept sensor, in which the light signal is generated by the same physical phenomenon underlying the LASER principle, namely the stimulated emission. Lasers are light sources with very special properties that have allowed innovations in several fields, among which we can mention manufacturing, medical applications, metrology, data storage, communications, spectroscopy, microscopy and scientific applications.

Here we are proposing to use a laser as ionising radiation detector. There are two reasons that motivate a systematic feasibility study of the proposed sensor: first, in a laser cavity an intense electromagnetic field is present that stimulates instantaneously the emission of photons by the atomic/molecular levels that would be excited by the incident radiation. This aspect is of importance for instruments where the time resolution is a critical parameter as for instance in PET, PET-ToF systems. Second, the emitted photons are collimated in a beam, allowing for integration to fibre devices.