The high resolution gamma ray facility GAMS makes use of the fact that, at the ILL reactor, one can obtain extremely high specific activities when exploiting thermal neutron capture at an in-pile target facility. This allows us to aim for the application of gamma spectroscopy with the highest possible energy resolution. Many studies on this facility have aimed to contribute to our understanding of the structure of nuclei. Others are devoted to the determination of standards and fundamental constants or to deduce information about short lifetimes of excited nuclear states.

Spectroscopy: classical "complete" spectroscopy of the decay of excited nuclear states
Lifetimes: measurement of lifetimes of excited nuclear states (by gamma-ray induced Doppler broadening - GRID)
Standards: measurement of fundamental constants ; measurement of standards for x-rays and gamma-rays
Crystal Difraction: detailed studies of crystal diffraction processes
Inter-atomic Potentials: study of slowing down processes of atoms recoiling in matter

PN3 is in fact a set of two gamma-ray spectrometers GAMS4 and GAMS 5 installed on both ends of the neutron tube H6-H7.