Adaptation of the LIMM technique data treatment to perform measurements in vacuum

Dielectric materials are used as thermal regulator on satellites, as they offer for the embarked electronic devices the required protection. Their behavior in space environment must be studied in order to prevent electrostatic discharges that can be harmful for satellites. An irradiation chamber called MATSPACE has been built to study these materials. It is equipped with various material characterization devices. We will focus this paper on the Laser Intensity Modulation Method (LIMM) and the Split Faraday Cup (SFC) arrangement in the chamber. In a first approach it was necessary to reconsider the thermal aspect of the LIMM data treatment as it was now used under vacuum. In a second step, a new deconvolution treatment has been developed in order to recover the charge profile near the surface and further in the bulk. The influence of frequency range in which the signal is recorded will be also presented.