The high sensitivity Italian Spring Accelerometer (ISA) for fundamental physics in space

Abstract

Many space experiments in fundamental physics require accelerometers of high sensitivity. We present here the “Italian Spring Accelerometer” (ISA), operating at low frequencies (10 −4 ÷ 1 Hz), whose sensitivity is expected to be better than 10 −12g Hz . An ISA prototype has been completed and used for ground tests. We describe ISA and report the results obtained from the exprimental measurements. We have conceived a differential accelerometer based on the same physical principles as ISA which, if operated at low temperatures, could reach a sensitivity better than 10 −14g Hz and be of interest for testing the Weak Equivalence Principle in short-time free fall conditions.