Calculations and TPMC simulations of the reduction of radioactive decays of a noble gas by cryo-panels

We compare two different methods which describe the radon suppression for different baffle temperatures. The first method calculates the suppression factor analytically, using the effective pumping speed and the transmission probability of the baffles simulated with the Test Particle Monte Carlo code MolFlow+. A newly introduced effective sticking coefficient takes into account the radon lifetime and its mean sojourn time on the cold copper baffles. For the second method the MolFlow+ code was extended to simulate directly the radon lifetime and sojourn time. At the end experimental data are compared to the simulations and the mean sojourn time is determined as a function of the baffle temperature.