In flight evaluation of LFI radiometers thermal susceptibilities

Abstract

In this technical note we provide a preliminary estimation of the impact of temperature fluctuations at the level of different thermal stages on the output signal of the Planck-LFI radiometers. Thermal susceptibilties at the level of Front End Modules (FEMs), Back End Modules (BEMs) and 4K Reference Loads have been evaluated throughout the ground test phases of the instrument. Due to bias optimization and different environmental conditions an in-flight measurement is needed to get an estimate of the temperature fluctuations impact on science and to setup an attempt of reduction of such a systematic effect by using houskeeping informations.