  In order to measure the energy of neutron fields, with energy ranging from 8
keV to 1 MeV, a new primary standard is being developed at the IRSN (Institute
for Radioprotection and Nuclear Safety). This project, micro-TPC (Micro Time
Projection Chamber), carried out in collaboration with the LPSC (Laboratoire de
Physique Subatomique et de Cosmologie), is based on the nuclear recoil detector
principle. The instrument is presented with the associated method to measure
the neutron energy. This article emphasizes the proton energy calibration
procedure and energy measurements of a neutron field produced at 127 keV with
the IRSN facility AMANDE.
