B. Todd et al. 19 th August 2009 The Beam Interlock System Thanks to: Machine Protection Panel, R. Schmidt, B. Puccio, M. Zerlauth and many more… 0v2

CERN, the LHC and Machine Protection 2 of 15 Machine Protection System

CERN, the LHC and Machine Protection 3 of 15 Beam Interlock System Locations Designed to protect CERN high energy accelerators = SPS / LHC / INJ / EXT

CERN, the LHC and Machine Protection 4 of 15 Beam Interlock System Function BIS Both-Beam Beam-1 Beam-2 ~200 User Systems distributed over 27 kms LHC has 2 Beams Some User Systems give simultaneous permit Others give independent permit

CERN, the LHC and Machine Protection 5 of 15 Signals

CERN, the LHC and Machine Protection 6 of 15 Signals

CERN, the LHC and Machine Protection 7 of 15 Signals NON-CRITICAL / Monitoring = DIFFERENT device Hardware MATRIX = 9500 Complex Programmable Logic Device (CPLD) Hardware Description Language (VHDL)

CERN, the LHC and Machine Protection 8 of 15 Layout In LHC, BIS forms a transparent layer from User System to Beam Dump

CERN, the LHC and Machine Protection 9 of 15 Layout

CERN, the LHC and Machine Protection 10 of 15 Layout

CERN, the LHC and Machine Protection 11 of 15 Beam Permit Loops & BICs Square wave generated at IP6 -Signal can be cut by any Controller -Signal can be monitored by any Controller When any of the four signals are absent at IP6, BEAM DUMP! 4 fibre-optic channels from Point 6 1 clockwise & 1 anticlockwise for each Beam Beam Dump Beam-1 and Beam-2 Beam Interlock Controllers (BIC) 16 BICs per beam - Two at each Insertion Point Up to 20 User Systems per BIC 6 x Beam-1 8 x Both-Beam 6 x Beam-2 Beam-1 / Beam-2 are Independent!

CERN, the LHC and Machine Protection 12 of 15 LHC Function

CERN, the LHC and Machine Protection 13 of 15 Typical Hardware User Interface BIC (Front) BIC (Rear)

CERN, the LHC and Machine Protection 14 of 15 Specification Fast = 100μs over 27 km Redundant User Permit = Safe Redundant Power Supplies = Available Glitch Filters = Available Critical is Hardware Only Critical physically separated from non-critical NO remote update of critical CAN remote update non-critical Modular in-house design 20 year lifespan Every Board Tested during fabrication Every Controller exhaustive critical test before installation (4h sequence) Installed system can be fully tested on demand Pre operational checks Full online consistency monitoring during operation Post operational checks

CERN, the LHC and Machine Protection 15 of 15 FIN

CERN, the LHC and Machine Protection 16 of 15 References / Acknowledgements [1] CERN’s mission statement [2] Aerial view of CERN [3] LHC Machine Protection [4] CERN photography [5] CERN. LHC Cost and Schedule Review Committee Report, 15 December [6] CERN. ATLAS Technical Proposal for a General-Purpose pp Experiment at the LHC at CERN, 15 December [7] CERN. CMS Technical Proposal. [8] CERN. ALICE Technical Proposal for A Large Ion Collider Experiment at the CERN LHC, 15 December [9] CERN. Status of the LHCb Experiment, 30 September [10] CERN. CERN AC Note 2000/03: General description of the CNGS Project, [11] CERN, LHC FAQ

CERN, the LHC and Machine Protection 17 of 15 References / Acknowledgements [12] CERN - Scientific Information Service - Archive. Chronologie du CERN, [13] R. Assmann and other. requirements for the LHC collimation system. In Proceedings from EPAC’02, La Vilette, Paris, France, 3-7 June adapted from [14] V. Kain et al. Material damage test with 450 gev LHC-type beam. In Proceedings from PAC’05, Knoxville, TN, USA, May [15] R. Schmidt and J. Wenninger. Protection against accidental beam losses at the LHC. In Proceedings from PAC’05, Knoxville, TN, USA, May