My Bolometer is Running a Fever, or Why Very Low Noise Performances Requires Global Design of the Apparatus

Thanks to intensive developments, bolometer sensitivity has improved by orders of magnitudes. Measurements now involve energies that are incredibly small, when compared to everyday hardware. Thus, when used in an industrial environment, taking advantage of their performances requires much care to prevent noise from overwhelming the signal. In this paper, we show, taking the Planck Instrument as an example, that proper design of subsystems is mandatory, but no longer sufficient to achieve required performances. A global design of the apparatus for low noise is needed, and we explain how to do it.