1. to TT10 Nitrogen or helium gas LN2 Storage vessel buffer storage vessel 1 2 3 4 G1G2 Magnet cryostat VALVE BOX Schematic diagram of the cryogenic system

2. System Operation OperationValve 1 Valve 2 Valve 3 Valve 4 Valve 5 Valve G1 Valve G2 Fill (cool) Cryostat from Buffer Vessel ClosedOpen ClosedOpen Closed Fill Cryostat from LN2 Storage Vessel OpenClosedOpen Closed Empty Cryostat ClosedOpenClosedOpen ClosedOpen Pre-cool Buffer Vessel or bypass Cryostat Open ClosedOpenClosed

3. to TT10 nitrogen or helium gas LN2 Storage vessel buffer storage vessel, 150 l 1 2 3 4 G1G2 Magnet cryostat, 100 l VALVE BOX nToF11 SCHEMATIC DIAGRAM OF THE CRYOGENIC SYSTEM All valves and junctions are in the valve box All valves are remotely operable in TT2 Valve 1 is a proportional valve Safety pressure relief valves are not show Demountable joints LN2 lines Cold nitrogen gas lines Warm nitrogen gas line GROUND LEVEL TUNNEL TT2A heat exchanger TUNNEL TT2 5