Undergraduate Research at Jefferson Lab

Helium Mass Flow Sensor

Student: Joe Jayne

School: University of New Hampshire

Mentored By: Kevin Jordan

Jefferson Lab uses liquid helium in cryomodules to cool SRF (Superconducting Radio Frequency) Cavities so that they are superconducting. The health of a cryomodule may degrade over time causing it to dissipate more power. Current methods of measuring a cryomodule's health are invasive and require the accelerator to be off. The Helium Mass Flow Sensor introduces a new method of monitoring a cryomodule's health by measuring the mass flow of helium gas that leaves the cryomodule. The flow rate of this helium gas can be related to the power dissipated in the cryomodule. So far, multiple flow meters have been installed and are currently being calibrated against the cryomodule electric heaters. Because the Helium Mass Flow Sensor can be used while the accelerator is running, accelerator operators can make a measurement of a cryomodule's health relatively quickly and far less intrusively. This information can be used to easily identify cryomodules that need maintenance or replacement.