ELENA Source Vacuum System, LNS R. Kersevan Integration and Installation Committe – 18 Sept 2014

ELENA LNS Vacuum System - R. Kersevan – IIC Meeting – 18Sept2014 Agenda: 1.Integration Layout (LNS + first part of LNE00) 2.Vacuum Hardware: Pumps, Gauges, Valves, etc… 3.Pressure Profile Calculations 4.Conclusions

ELENA LNS Vacuum System - R. Kersevan – IIC Meeting – 18Sept Design and Integration Status Report Design of the LNS line has evolved to a mature stage; All necessary vacuum devices have been integrated; Optimized design of a Differential Pumping System (DPS) has been done, and integrated;

ELENA LNS Vacuum System - R. Kersevan – IIC Meeting – 18Sept Design and Integration Status Report List of vacuum hardware: Pumps: 4x 1200 l/s turbos 1x 1400 l/s “ZAO” NEG 1x 1000 l/s NEXTorr Bellows: 3x Gauges: 4x ionization + 4x Pirani Gate Valves: 1x DN x DN63 (Series 48, all-metal) Manual Valves: 3x DN35 (all- metal)

ELENA LNS Vacuum System - R. Kersevan – IIC Meeting – 18Sept Pressure profile calculations LNS, the Ion-Switch (IS), and the part of LNE00 connecting the IS with LNR have been modelled in detail As usual, the montecarlo code Molflow+ has been used. The CAD models exported in STL format have been used The gas load of the H +- source, as per R. Gebel, has been simulated: E-2 mbar*l/s (6 sccm) The transmission probability from the source to the “Y” chamber pumping the electrostatic (ES) kicker on LNR has been calculated

ELENA LNS Vacuum System - R. Kersevan – IIC Meeting – 18Sept Transmission Probabilities (pumping surfaces in RED) Source to IS: ~ 2.4E-4; IS to LNR: ~ 1.2E-2; Combined: ~3.0E-6 Gas Load to LNR: ~ 2.8E-7 mbar*l/s

ELENA LNS Vacuum System - R. Kersevan – IIC Meeting – 18Sept Conclusions The challenging design of the DPS for LNS has been done: integration considerations have left only 60 cm for the DPS! In spite of that, only ~ 1 H 2 molecule out of 4,500 reaches the Ion-Switch; Of the initial gas load of 9.44E-2 mbar*l/s only 2.8E-7 reach the “Y” chamber on LNR. A similar amount will reach LNR moving down LNI, to the injection septum/kicker assembly; The pressure rise at LNR will be only marginal, and should not saturate neither the NEG pumps nor the NEG-coating of the LNR; Fabrication of the components of LNS can and should start soon, in order to meet the pre-commissioning schedule; OPEN ISSUE: a 30 mm ID orifice restriction between the two domes of the DPS is suggested, as it decreases the transmission probability

ELENA LNS Vacuum System - R. Kersevan – IIC Meeting – 18Sept2014 Many thanks to C. Eymin, L. Dassa, S. Maridor for providing informations, documents, data and help