CNGS Operation J Wenninger Part 1 CNGS beam

CNGS Operation J. Wenninger Part 1 : CNGS beam operation. Protons on their way to the target. CNGS specialties. Part 2 : Extraction Interlock System. Detailed description. Acknowledgments : Edda, Verena, Konrad … for figures, photos and numbers. 19/06/2008 1

CNGS ‘Facility’ • A dedicated primary beam line (TT 41), a target chamber (target T 40), a decay tube & a muon detection infrastructure. • ‘Attached’ to the LSS 4/East extraction channel. 19/06/2008 2

CNGS Tunnels 19/06/2008 3

19/06/2008 4

Our Goals Send 4. 8 x 1013 protons to target in every CNGC cycle Tune, tune … Keep the beam within +- 0. 5 mm of the target axis to prevent damage ! Interlocks, interlocks… 19/06/2008 5

CNGS Magnetic Cycle • The CNGS beam magnetic cycle is almost identical to the FT beam: the only difference is the much shorter 400 Ge. V flat top – only 90 ms: • 2 fast extractions are programmed 20 ms and 70 ms from the start of the flat top. P (Ge. V/c) • Same optics and tunes than FT beam: Q = (~26. 62, ~26. 58) • Injections at 0 and 1200 ms. • Ramp from 1260 to 4200 ms. • Flat top from 4200 to 4290 ms. • Extractions at 4220 and 4270 ms. • Cycle length 6 s – 5 BPs. 19/06/2008 Time (ms) 6

CNGS Beam CNGS beam = FT beam with more intensity, up to 4. 8 x 10 13 p. LHC FBCT Longitudinal: • 2 batches of ~10. 5 ms (5/11 of SPS). • 2 gaps of ~ 1 ms (kickers !). • Bunch spacing 5 ns. • Bunch length at 400 Ge. V ~ 2 ns. Transverse: • Normalized emittance e* 8 -10 mm. • Beam sizes at 400 Ge. V (10 mm): Batch 1 19/06/2008 Kicker gaps Batch 2 -Wire scanner 51995 s. H/V 1. 4/0. 8 mm -Target T 40 s. H/V 0. 5/0. 4 mm 7

LSS 4 Extraction Channel 19/06/2008 8

LSS 4 Fast Extraction Channel 5 extraction kicker magnets (MKE) operated at 50 k. V. 6 septum magnets (MSE), installed on a movable girder. 4 horizontal and 4 vertical bumper magnets: - Horizontal extraction bump of 31. 1 mm @ monitor BPCE. 418 TPSG protection element for the MSE. 19/06/2008 9

Extraction Kicker MKE Key constraint for the fast extraction : < 0. 1% beam loss during extraction ! Radiation in ECX 4 + activation of extraction channel This means that : • Beam gaps must be VERY clean. • MKE settings (delays, kick length) are critical. Preliminary settings Beam Kicker Waveform 19/06/2008 10

MKE 4 Kick Alignment OASIS global to observe beam and kick. Note that the BEST tuning parameter are the losses in LSS 4 : • Minimize on first extraction. • Adjust second extraction to have no losses : the first batch is gone – there is space !!! 19/06/2008 11

MKE is the heart of the extraction Beam Energy Tracking System Extraction Interlock System MKE Slow Timing Extraction Pre-pulse Beam kicked into septum gap Both SW and HW interlock systems act on the MKE and on the (timing) beams with destination CNGS (for SIS), but not on the beam dump and not on the SPS ring HW interlock system. There is NO coupling with LHC or FT beams !!! 19/06/2008 12

Beam Energy Tracking • One of the worst failures of the extraction system is to : • Kick with too little/high voltage at 400 Ge. V. • Nominal kick significantly below 400 Ge. V. • To protect the extraction channel and line against such failures, the MKE has an internal Beam Energy Tracking System (BETS) that ensures that: • The measured energy for CNGS is within ~0. 5% of 400 Ge. V. The momentum aperture of the line is > +- 0. 6%. The energy measurement is based on the current of the main dipoles. • The measured kicker voltage must be 50 +- 2 k. V. Inhibits the extraction (no kicker fault !) if not OK ! !! The BETS does not take into account the energy change due to a radial position offset – please do not trim the radial position for Q’ etc measurements on the flat top – or stop the extraction first !! 19/06/2008 13

MKE Trigger Logic 1. Extraction – 13 ms : the PFNs (Pulse Forming Networks) are charged provided the extraction interlock system gives the green light. 2. Extraction + 0. 4 ms : the MKEs are triggered when the RF pre-pulse arrives provided that : i. The extraction interlock systems gives the green light. ii. The BETS system gives the green light. NB: the +0. 4 ms delay wrt ‘nominal’ extraction time is due to delays in the RF prepulse generation & CTRVs -13 ms ~+0. 4 ms PFN voltage Extraction interlock permit LHC BETS CNGS BETS 19/06/2008 14

MKE : Missing Triggers • If for one reason or another the MKE PFN’s are charged, but not triggered normally (last ‘minute’ interlock, no pre-pulse) the PFNs will be discharged in the clipper switches. • Such abnormal discharges should not be repeated for many cycles, therefore the MKE will go to FAULTY state when this happens more than 4 times over a certain time interval: • If it happens, switch the kicker back on and try again. • If the problem occurs again after a few cycles, check or call some experts… 19/06/2008 15

Extraction Septum Element L mag (m) B (T) Kick/mag (mrad) I nom (A) Septum Thickness (mm) Gap Height (mm) MSE 2. 24 ~1. 5 2. 1 ~20000 17. 2 20 MSE 19/06/2008 Extraction channel 16 16

LSS 4 Extraction BLMs Beam loss due to a large vertical size or tails appear here, at exit of septum (largest V size). ~ 2 x 1013 • The LSS 4 BLMs are connected to the ring BIS system (and to the dump) because losses can come from the extracted or circulating beam. • The interlocks is latched after 3 cycles by SIS! p Loss distibution is due to residual beam in the abort gap. Septum magnets TPSG BLM 1 BLM 2 19/06/2008 BLM 3 BLM 4 BLM 5 BLM 6 BLM 7 BLM 8 17

RF & Kickers Tuning for clean gaps! The voltage is ramped up to ~1. 3 -1. 4 MV after injection to minimize beam in the gaps ! 19/06/2008 Constant Voltage 0. 9 MV 18

MKP for CNGS • An alternative method to clean the gap is to advance the second kick of the injection kicker a bit. • Necessary if it does not work with the RF. • Used regularly in 2007… ROBUST !! 19/06/2008 19

TT 40/TT 41 Transfer Lines 19/06/2008 20

TT 41 Transfer Line • ~720 m long, 837 m if TT 40 is included (from MSE). • A string of 8 dipoles (MBSG, RBI. 410010) is used to bend the beam towards CNGS. For LHC operation the MBSG is at 0 current. • The lattice is basically the same as for the SPS (betatron & dispersion functions). • Final focus at the end to reduce beam size on target. • Aperture for the beam : > +- 20 mm in H/V. 19/06/2008 21

Main Bends (RBI. 816) powering Interlock DCCTs • The TT 41 and TI 8 main dipoles are powered by a single converter, with switches (mechanical and electronic) to send the current into the correct magnet string. • The mechanical switches are interlocked with the access chains. To run CNGS when TI 8 is in access (like now !), the TI 8 (load) switch must be to Earth. If that is not the case, there will be an access interlock on the PC & an alarm for the LHC access system! To control the switches – use the PC expert (Labview) program ! • To ensure that the switch position is correct, there are 2 ‘dummy’ ROCS channels that have only an interlock DCCT but no converter. The names of the ROCS are DCCT_TI 8 and DCCT_CNGS (also accessible from equipstate). MUGEF for ‘standard’ surveillance Mechanical swicthes 19/06/2008 • The 2 DCCTs are used to identify which branch is powered, and their current is interlocked like any other converter. 22

RBI. 816 Settings - nominal • For a SC with interleaved CNGS & LHC, the PC must normally switch load according to the cycle. RBI. 816 has settings for CNGS & LHC. • The switching will be implement with LTIMs that will be activated either by USER or from the DESTINATION information: o Not tested yet – JULY ? o For the moment the automatic switching is deactivated. LHC CNGS 19/06/2008 23

RBI. 816 in CNGS only mode • To run CNGS alone with LHC access veto on TI 8, the switching is deactivated and the IREF function of RBI. 816 must be zeroed MANUALLY in the trim editor !! • If the function for LHC is not zeroed, the CNGS dipoles will pulse at the equaivalent energy of ~ 520 Ge. V: o Not a problem for the magnets themselves (D. Smekens dixit). o Could perturb steering and optics due to the change of remanent field ! >> watch out when creating new super cycles!!!! CNGS LHC 19/06/2008 24

Beam Position Monitors TT 40/41 • 23 H+V position monitors are installed in TT 40 & TT 41: o 18 button monitors (TT 41). o 5 couplers: 4 in TT 40, 1 in front of T 40 (on the target table). • Self-triggered electronics: o No gain, but a variable integration window (0. 4 or 8 ms). Default integration window for regular operation is 8 ms. o At low intensity there can be triggering problems… 19/06/2008 25

Steering TT 40/TT 41 • Steering in TT 40/41 is rather easy and reliable (MICADO 1 -3 correctors). • The line is very stable and requires very little steering : ~ once per 1 -2 weeks ! • The positions are interlocked, always steer towards the REFERENCE trajectory (beam-target alignment) ! • The interlock margin on correctors is +- 15 mrad, +- 20 mrad for the last 4. Tolerances : (changes are possible) +- 2 mm +- 4 mm +- 0. 5 mm !! 2007 reference !! >> will be updated !! Those offsets are ‘normal’ : TL-target (mis) alignment !! 19/06/2008 26

TT 40/TT 41 BLMs • In 2007 we had NO losses in the transfer lines very low thresholds. • The TT 41 thresholds are 5 m. Gray (compare to 50 -200 m. Gray in ring). • BLMs around the TED and at the collimator in front of T 40 have higher thresholds to avoid false interlocks when the beam is dumped on the TED. TT 40 TED ~ TT 40 2. 5 x 1013 p ~ 2. 5 x 1013 p TT 40 TED Collimator in front of T 40 TI 8 – not relevant… TT 41 After target, not interlocked !! 19/06/2008 27

Timing 19/06/2008 28

Extraction Timing / I Legacy CTIMs The timing must be identical on ALL CNGS users ! Please do not change it - it has consequences on interlocks, logging… CTIMs RF extraction pre-pulses (RF 2) The extraction window open delay must be 18 ms – very critical – if it is different the MKE will not trigger. 19/06/2008 29

MKE Trigger Timing • The fast extraction pre-pulses are generated by the SPS RF system (in the Faraday cage in BA 3) and distributed over the SPS. • A local timing module (CTRV) filters the pre-pulses and distributes them to the SPS kickers (also valid for MKP) – via an LTIM. • For MKE 4/MKE 6 the pre-pulse distribution is filtered on beam DESTINATION (also valid for the extraction warning event): • CNGS pre-pulses are only distributed when the beam destination is CNGS. • LHC pre-pulses are only distributed to MKE 4 when the DYNAMIC DESTINATION is TI 8_DUMP or LHC 2_TI 8. • LHC pre-pulses are only distributed to MKE 6 when the DYNAMIC DESTINATION is TI 2_DUMP or LHC 1_TI 2. >> If the beams go to spare – kickers do not charge and do not kick ! --> no testing possible without beam !!!!!!!! >> For LHC the beams must be declared ‘TO_LHC’ in the sequence. 19/06/2008 30

For Info : MKE Extraction LTIMs MKE 6 kicker MKE 4 kicker Normally this should not be touched !! 19/06/2008 31

Multiple CNGS cycles • When we run with 3 CNGS cycles mapped to different USERs (CNGS 1 -6), the ring & TT 10 settings may be different for the 3 cycles/USERs. • In any case all PC settings will be independent for all cycles/users. • The settings for • East Extraction (bumpers, septa), • CNGS Transfer (TT 40 + TT 41), • Interlocks … must be identical on all cycles. A trim must be propagated to all cycles ! The following page has recommendations & rules for settings copy : http: //jwenning. home. cern. ch/jwenning/SPS_Settings. html 19/06/2008 32

Secondary Beam 19/06/2008 33

CNGS Secondary Beam 2. 7 m 43. 4 m 100 m 1095 m TBID / 2 Ionization Chambers TBID: Target Beam Instrumentation Downstream p+C (interactions) p+, 19/06/2008 18 m 5 m 67 m 5 m Muon Detectors K+ (decay in flight) m+ + nm 34

Extraction Interlocking Target Horn 19/06/2008 35

13 carbon target rods 5 & 4 mm total length 2 m 19/06/2008 36

CNGS Muon Monitors p --> m + nm 19/06/2008 37

270 cm 11. 25 cm Muon Detectors 19/06/2008 38

Muons Profiles Good • A fixed display for muon profiles and status of target/horn/reflector/shutter is available. • It includes multiplicities and a status word (color) on the quality ! Ugly Medium 19/06/2008 39

Secondary Beam Control • The target is not under our control. • Horn and reflector are controlled through the working sets. • Important : The brilliant SW of the horn/reflector only allows control when a CNGS user is active. Without CNGS user in the SC, one cannot even switch the horn/reflector ON and OFF !!!!! 19/06/2008 40

Secondary Beam ‘Steering’ To steer the beam in the muon chambers, use orthogonal steering at target T 40 (Steering, Machine Specials menu – similar to T 2, T, T 6): Sensitivity : 1 mm @ pit 2 19/06/2008 0. 1 mm parallel steering (angle = 0) 41

Extraction Interlocks 19/06/2008 42

SIS for TT 40 • One SIS interlock tree is dedicated to TT 40. As usual SIS acts on the BICs and one the timing system. • The tree contains the usual stuff (PCs, BTVs, …) but also a surveillance of BLM thresholds (not too high !) and other parameters related to the HW interlock system Target BICs Timing inhibit that stops beams with destinations passing through TT 40 : CNGS, TI 8_DUMP, LHC 2_TI 8 43 19/06/2008

SIS for TT 41 • One SIS interlock tree is dedicated to TT 41. • The tree contains the usual stuff (PCs, BTVs, …) but also a surveillance of BLM and BPM thresholds and other parameters related to the HW interlock system Target BICs Timing inhibit that stops beams with destination CNGS 44 19/06/2008

MTG Inhibits The SIS signals in the sequence manager (External Conditions) 19/06/2008 45

HW Interlock System • The EAST extraction HW interlock system consists of 7 BIC modules. The hardware is identical to the SPS ring beam interlock system: • There 6 ‘standard’ BICs for TT 40 (TT 40 A& TT 40 B), TT 41 (TT 41 A& TT 41 B) and TI 8 (TI 8 U & TI 8 D). Each BIC sends its output to the master BIC. • There is one EXTRACTION MASTER BIC (‘EXT 2’). • The master BIC applies a complicated logic to handle CNGS and LHC consistently without the need to manually mask channels. This module is the most complicated component of the beam interlock system hardware. The output signal (‘permit’) of the master BIC is send to the MKE to enable/disable extraction 19/06/2008 46

(Un-)maskable Interlocks & Safe Beam Flag • The HW interlocks may be either UNMASKABLE or MASKABLE. • MASKABLE interlocks may be masked when the beam is ‘Safe’. A dedicate signal, the Safe Beam Flag (SBF) is distributed by a timing telegram to the BICs. If the SBF is TRUE, a mask is applied, when it is FALSE the masks are ignored. • The SBF is: • TRUE if the SPS beam intensity is < 1012 protons • FALSE if the SPS beam intensity is > 1012 protons • SBF generation: • The intensity is measured by the standard SPS hadron BCT one second before the fast extraction (only when fast extraction timing is enabled !). • The intensity is send to the SMP (Safe Machine Parameter) system to generate the SBF. • After a maximum of 3 seconds, the SBF is reset to FALSE by the SMP. 19/06/2008 47

Extraction Master BIC module with a special logic to cope with TEDs, CNGS & LHC beams. TRUE if SPS energy 400 +- 5 Ge. V TRUE if SPS energy 450 +- 5 Ge. V TRUE if TT 40 TED in beam TT 40 -A, TT 40 -B, TT 41 -A, TT 41 -B, TI 8 Upstream, TI 8 Downstream >> output of the corresponding ‘standard’ BIC modules TRUE if TI 8 TED in beam ‘Beam flags for and from the LHC, only for LHC injection. Only active when ‘TED-in TI 8’ = FALSE 19/06/2008 48

Master Logic (for CNGS) • TT 40 TED IN BEAM : • Only E_400, E_450, TT 40 A, TT 40 B are taken into account by the master for the interlock logic. • All other inputs to the master are ignored. • Either E_400 or E_450 flag must be TRUE. • Extraction OK if TT 40 A and TT 40 B are TRUE, and either E_400 or E_450 is TRUE. >> Extraction of LHC/CNGS beam to TT 40 TED • TT 40 TED OUT OF BEAM – CNGS case : • E_400 is TRUE. • TT 40 A, TT 40 B, TT 41 A, TT 41 B are taken into account for the interlock logic. • All other inputs to the master are ignored. • Extraction OK if TT 40 A, TT 40 B, TT 41 A and TT 41 B are TRUE. >> Extraction of CNGS beam to T 40 >> There is a similar, but more complicated logic for the LHC beam when E_450 is TRUE. 19/06/2008 49

HW Interlock ‘Types’ For the CNGS fast extractions there are 3 types of interlocks based on : • Continuous surveillance of parameters, like (end-)switches. The associated signals change their state rather ‘rarely’. • Vacuum, TEDs, target… • Pre-extraction surveillance where the interlock signals are evaluated a short time BEFORE extraction. The signal is FALSE by default and switches to TRUE for a short time interval around extraction if all conditions are correct. • Surveillance of the beam position around extraction point and of the PC currents. • Post-extraction surveillance where the interlock signals are evaluated AFTER extraction. This type of surveillance concerns beam instrumentation. The signal is switched to TRUE for a short time around extraction. The interlock signal is latched (FALSE) at the level of the client if a measured beam parameter is out of tolerance. • Beam losses and beam positions in the transfer lines. Both Pre- and Post-extraction surveillance tasks are triggered by timing events coupled to the main extraction event. 19/06/2008 50

‘Obstacles’ Interlocks Beam ‘obstacles’ that provide inputs to the HW interlock system: • Vacuum valves: must be open. • TBSE (personnel protection stopper): must be OUT of beam. • TED (dump): must be IN-BEAM or OUT of beam (interlock if moving). . • Decay tunnel shutter: must be open. • Target: must be at a valid position. • BTVs: (maskable) • Positions : Al, C (OTR), Ti (OTR), Out. • Should be Out by default. • Only the Carbon OTR screen is allowed in beam. • Al or Ti interlock ! • Interlock when moving. • Last screen in front of T 40 is locked in beam (C). • Comment for TI 2 & TT 60 & TI 8 : for those lines there are no C OTRs. The Ti screens are allowed in beam ! 19/06/2008 51

Misceleanous Inputs There are some rather unusual inputs to the Extraction Interlock System: • TCC 4 Ventilation: interlock is generated if the ventilation system of TCC 4 (T 40 target chamber) is in ‘Access Mode’. • Hadron stop cooling: interlock is generated if the hadron stop (after muons monitors) is not cooled. • Fire alarm: A fire detector for TCC 4 is also in the chain… …and there is of course the BIG RED INHIBIT BUTTON, in the rack next to the MTG inhibit buttons. 19/06/2008 52

Magnets Inputs Interlocks related to magnet surveillance: • WIC (Warm magnet Interlock Control): magnet temperature surveillance interlock for TT 40 and TT 41 magnets (one input per TL). The WIC PVSS supervision is available from the SPS console manager (SPS Control Equipment Control). • MSE girder: this interlock signal combines the following MSE surveillance • MSE cooling & temperature. • MSE girder : must be in beam, not moving and within +- 2 mm of nominal position. Note that there is NO girder optimization needed for the LSS 4 fast extraction. • MSE PC must be ON. 19/06/2008 53

Powering Failures Powering ‘failures’ are among the most likely and most critical failures : • Wrong converted setting surveillance of the current VALUE. • Converter failure FAST surveillance of the current CHANGE/STATE. Examples of simulated powering failures TT 41 Main Bends Tolerance Reaction time ~ 2 ms 19/06/2008 Tolerance Reaction time ~ 5 ms 54

PC Current Surveillance • The ROCS system provides a pre-extraction surveillance, the so-called FEI (Fast Extraction Interlock). The current of selected converters has to match a reference within a pre-defined tolerance. The surveillance is performed at the last possible moment ~ 2 milliseconds before extraction. • This system provides in total 6 inputs to the BICs for CNGS, all inputs are MASKABLE: LSS 4 bumper converters (H+V) TT 41 converters TT 40 converters MBI main bend converter MSE. 418 converter Interlock DCCTs for shared main converter • Operational current tolerances : RBIH. 4100107, RBIH. 400309 0. 2% (dipole strings) RBI. 410147/RBI. 81607 0. 1% (main dipole string) Interlock DCCTs 1. 0% RBI. 410010 0. 1% Septum MSE 418 0. 1% Main quad strings (D/F) 0. 2% Matching quads 0. 5% Corrector magnets 15 mrad Extraction bumpers 1 mrad 19/06/2008 (switching dipole TT 41 -TI 8) (20 mrad for last elements) 55

PC Surveillance : Structure A selection of PCs of one crate are grouped together and associated to one input of a selected BIC: • Each PC of the group has a fixed reference and a tolerance. • Checking of a group is triggered by the timing events associated to the extraction. • The group and its settings are identical for ALL CNGS cycles or for ALL LHC cycles: no distinction between CNGS 1, CNGS 2 etc users. >> simplifies the settings organization and ensures that the settings are consistent for all beams of the same type. The interlock settings are not persistent in the ROCS FECs, i. e. after a reboot the settings must be reloaded with the application !! 19/06/2008 56

PC Surveillance Timing • For each extraction, the ROCS system provides two 2 ms long pulses when interlock = TRUE which sets a strong constraint on the event sequence (minimizes possible errors). • The LEGACY events that trigger the ROCS are: • OEX. FINT 1 -CTM • OEX. FINT 201 -CTM at -13 ms at -1 ms (wrt extraction) 2 ms pulse 19/06/2008 57

PC Interlocks Application / 1 • An application using RBAC to limit access to the interlock settings is now available (but still under development !). • The interlock settings are stored in files (for the moment) with a digital signature. The application automatically loads the latest settings, and saves a new reference after every change. • Three access roles for settings control: • MCS-SPSOP : all people on SPS shift + coordinators • Can change references & ‘active status’ for steering magnets. To update settings after steering if out of tolerance + disable for target scans. • MCS-SPSEXPERT : for the moment only Jorg, Verena & Karel • Can change all settings and tolerances, except the settings for the special DCCTs of the main bends. • MCS-SPSGURU : for the moment only Jorg & Verena • Can do everything, including reading a file with a ‘corrupt’ digital signature. >> 2007 experience showed that EXPERT and GURU access is only needed for setup & commissioning periods because the PCs are stable. 19/06/2008 58

PC Interlocks Application / 2 SPS Control Beam Interlocks Extraction PC Interlocks RBAC log in Most useful button !! Send all settings BIC input Access : • NORMAL • EXPERT • GURU 19/06/2008 Reference & tolerance in bits Reference & tolerance in A 59

ROCS Interlocks Application / 3 Select cycle & transfer (standard LSA selection) Compare with LSA settings Import settings for selected lines DB and FEI reference, difference & tolerance 19/06/2008 60

FMCMs • The FMCM (Fast Magnet Current Change Monitor) is a device developed at DESY for HERA to detect powering failures on PCs, in particular when the current decay is very fast. • The principle of the FMCM is to detect the change in voltage DV L is the circuit inductance when the current decreases rather than to measure directly the change in current DI, because DI/Dt is more sensitive when DI and Dt are small ! • 5 circuits are monitored by FMCMs: 19/06/2008 Circuit I Nominal (A) MSE 418 RBIH. 4001 (MBHC) RBIH. 4003 (MBHA) RBI. 410010 (MBSG) RBI. 410147 (MBG) 20015 674 840 3086 3968 Measured DI/I (%) Threshold 0. 12 0. 03 0. 01 0. 02 0. 01 D I/I (%) Specification for CNGS 0. 2 0. 5 0. 1 0. 05 0. 1 61

FMCM Signal Timing Large voltage changes inhibit FMCM interlock signal • The FMCM removes its interlock when the current is stable on the PC flat top. • During ramp up/down the large voltage changes interlock. • On the ‘flat bottoms’ the FMCM interlocks because I is too low. Excellent protection against attempt to extract during the ramp !!!!!! 19/06/2008 62

Other PC Interlocks There are 2 additional PC interlock: • Horn and reflector: PCs must be ON. • MSE Fast internal ‘Sum Fault’: fast internal interlock of the MSE converter. Similar to the SPS MB and MQ interlocks (to BIS in BA 3). Very fast signal, delay ~ 1 -3 ms. 19/06/2008 63

Beam Position in LSS 4 • The position of the circulating beam is checked before extraction and interlocked if not within tolerance. It is NOT latched. • The settings are controlled/monitored from the Steering Application (SPSRing), menu Machine Specials, BPM interlocks. • Beware: • The interlock is generated by MOPOS – changing the gain for the first turn may lead to interlocks if the signals are saturated at 400 Ge. V !!! • When the gains are changed (intensity change…) it may be necessary to RECALIBRATE the MOPOS BPMs to get correct positions !! Interlocked BPM list. Out of tolerance BPMs are highlighted in RED! Corrected positions (BPM non-linearity) 19/06/2008 Measured positions Interlock settings 64

Beam Position in TT 40/TT 41 • The interlock on the beam position in TT 40/TT 41 is LATCHED when out of tolerance to stop further extractions. • The CNGS beam position interlock settings are controlled from the Steering application (CNGS transfer), menu Machine Specials. • The latch status & reset available in the panel. • The interlock settings are identically for ALL USERs (not PPM). • The settings are declared as critical settings (and stored) in LSA: protected by a digital signature and RBAC logging (role MCSBPCNGS). Authorized settings editors (as of today): Verena, Edda, Jorg 19/06/2008 65

Post-Mortem for Trajectory • The Steering appl. provides a Post-mortem freeze that is activated by default for CNGS: o Freezes the display on the last acquisition and changes the DV frame to orange. o Stores (internally) the last acquisition with beam. • It is possible to monitor ALL users and use the steering as fixed display with incorporated PM. In case the BPM interlock is latched, this provides a display of the last trajectory (background color to orange). To help taking a decision, i. e. reset and continue, or stop and think ! 19/06/2008 66

Beam Loss Interlocks • The BLM thresholds are the same for ALL USERs. They are declared as critical settings (same as BPMs). Authorized to change settings : ~ all people on SPS shift + SPS supervisors. RBAC role is MCS-SPSOP. • The TL BLMs latch their interlocks. • To reset, click there. 19/06/2008 67

BI Interlock Timings LSS 4 BPM Transfer line BPMs and BLMs Latch 19/06/2008 68

Interlock Monitoring 19/06/2008 69

Standard Supervision • The usual BIC supervision application is also available for the East Extraction Interlock System. • The application is identical to the SPS ring application, and provides the same functionality (masks, status, history buffer…). • But there are many very short signals for extraction interlocking, and this application is not so easy to use. Therefore… 19/06/2008 70

Time Evolution Display Under the ‘Show View’ menu of each BIC panel, the option ‘Permit Status Tracker’ opens a graphical display of the interlocks that is refreshed for each cycle. • Overall ‘impression’, but difficult to make a precise diagnostics. • Warning : does not work properly (yet) for the master BIC EXT 2 !! 19/06/2008 71

Extraction Interlock Monitor • To ease the diagnostics of the Extraction Interlock System, special application analyses the signals and produces a simple status, OK or NOT-OK for each cycle. • Console manager : ‘SPS Control’ ‘Beam Interlocks’ ‘CNGS Extraction Monitor’. • Exists also for TI 8. and TI 2. Main screen Interlock signal to MKE, BIC EXT 2 Index of first faulty channel 72

Extraction Interlock Monitor : details BIC detail The green/shadowed regions indicate where the signal must be = 1 (TRUE) to be OK (and to give status = green ! Time evolution of the signal A tooltip with the channel description should appear is you pass the mouse over the pads. . If the console manager does not interfere ! 19/06/2008 73

Masks Color coding : Input OK Input not OK Input masked and not OK Status of the Safe Beam Flag, TRUE masks are applied 19/06/2008 74

MKE LTIMs The status/arrival of the timing for the MKE can be monitored from the LTIM menu, here example of MKE 6 – for each destination. 19/06/2008 75

MKE BETS There is presently a problem with the BETS data for the CNGS: the LHC data is displayed instead of the CNGS data ! Will be fixed… The status of the BETS (energy & voltage) can be obtained from the BETS Details menu. 19/06/2008 76

MKE Scope A remote scope is available to monitor PFN charging, BTES and BICs ! PFN voltage Extraction interlock permit LHC BETS CNGS BETS 19/06/2008 77

2007 Experience It was much easier than I feared !! • Line and beam were stable and required very few interventions/steering. • The windows on the orbit corrector currents are sufficient to give margin for a few weeks of steering. • There were no problems at all with the numerous PC interlocks (including ROCS). • The LSS 4 beam position interlock (from MOPOS) was the trouble maker: • Fake interlocks in a few % of all cycles. • Issues of position reproducibility when the intensity is changed : needs careful calibration. 19/06/2008 78

(Interlock) Experts • • • MSE/MST/MKE : E. Carlier, B. Balhan (BT) MKE BETS : E. Carlier, N. Voumard, N. Magnin (BT) ROCS : M. Jonker (CO) FMCM : M. Zerlauth (CO) WIC : P. Dahlen (CO) RBI. 816 (main dipoles) : L. de Oliveira (PO) MOPOS : S. Jackson (BI) TT 41 BPMs : T. Bogey, S. Bart-Pedersen (BI) BLMs : L. Jensen (BI) Target/shutter/TED/TBSE : M. Donze, A. Masi (ATB) BICs : B. Puccio, B. Todd (CO) • Interlock logic, setup, debugging, help-line : Jorg & Verena 19/06/2008 79

It’s all there… https: //cern. ch/sps-mp-operation/ • • • Detailed system description Test documents & system status Settings references Trouble-shooting Sample screen shots for important information • OP programs and diagnostics • … For use by the expert and by OP crews ! 19/06/2008 80