BWS E. Piselli – J. Emery On behalf of the BWS working group people

Status in March New bellows (longer life time ~ number of cycles) New HV PM voltage divider modification…(linearity response) New motion card firmware deployment New OP application

Status in March New bellows (longer life time ~ number of cycles) New HV PM voltage divider modification…(linearity response) New motion card firmware deployment New OP application

Pre LS1 bellows had experienced few vacuum leaks and the maximum rating given by the manufacturer was scans. During LS1 all bellows were exchanged but different stiffness and vacuum force of the new ones required new compensation springs. New bellows (longer life time ~ number of cycles)

Status in March New bellows (longer life time ~ number of cycles) New HV PM voltage divider modification…(linearity response) New motion card firmware deployment New OP application

New HV PM voltage divider modification…(linearity response) 3RR1.5RR470KΩ680KΩ 10KΩ C1 C2 C3 K -HV Signal OUT D1 A D2D3D5D4D6 C4 R=220KΩ C1=10nF C2=112nF C3=39nF C4=15μF R We have added 3 decoupling capacitors (15μF each) in parallel to the 3 last ones in order to: supply photomultiplier tube with an electric charge during the forming of the signal pulse restrain the voltage drop between the last dynode and the anode

Status in March New bellows (longer life time ~ number of cycles) New HV PM voltage divider modification…(linearity response) New motion card firmware deployment New OP application

We had same running version in the PSB and PS since and in LHC since Intensive use in CPS has shown its limitations. Firmware release was mandatory in order to: 1) Have a safe InitHW sequence (return from IN position) 2) Add extra safety necessary to avoid the ‘reset home problem’ 3) Mitigate about 1% of ‘lost Triggers ‘ 4) Be able to move the scanner to the home position from any position New motion card firmware deployment

Status in March New bellows (longer life time ~ number of cycles) New HV PM voltage divider modification…(linearity response) New motion card firmware deployment New OP application

New features: Can acquire data after a scan or get data from logging or measurement DB. Emittance evolution through a fill (either bunch-by-bunch emittance or average emittance per scan depending on number of bunches). Displays the bunch-by-bunch transverse profiles. Displays bunch-by-bunch emittances per scan in a bar graph. First fitting done in front end. Analyse button to fit the profiles with a five parameter Gauss. Common java package in all accelerators for fitting. Fit data will be send to logging database. Number of bunches automatically chosen from sequencer. All circulating bunches are selected by default. Updated automatically. There is also a possibility to manually select or deselect bunches (in configure bunch selection). User can choose between nominal beta function or measured beta function (stored in LSA) for emittance calculation. Number of bunches automatically chosen from sequencer. All circulating bunches are selected by default. Updated automatically. There is also a possibility to manually select or deselect bunches (in configure bunch selection). In “configure scanners” voltage and filter of PMs can be set. Predefined settings can be uploaded. New gain scale: gain now in per mille! M. Kuhn

April… Scanner B1 H1 – wire broken on 21/04/2015 after 359 scans Scanner B1 V1 – wire broken on 18/04/2015 after 49 scans Abnormal movement systematically seen from the CCC Movement blocked ~7 mm from home (out) position Audible noise indicated a physical obstruction inside the beam vacuum. TS1 (June) Both B1 H1 and B1 V1 removed. Both wires broken with no useable wire parts recovered. For the V1, some slight signs of impact on the ends of the forks, but no signs of damage, to ferrites or to holders. For the H1, no sign of damage Wires in both H1 and V1 were replaced and the same scanners were re-installed Some cycles were then made in air from the CCC – worked OK. Wire resistance checked OK. Handed back to vacuum around 16h15 on Monday 15/6. VSC made preliminary leak check around 17h00 with sensitivity ~ 4e-10 mbar.l.s-1. No leaks detected. VSC performed bakeout of the sector, with return to room temperature ~17h00 Friday 19/6 Device re-connected Friday evening and re-tested from the CCC – OK. R. Veness

TS1 (June) Interpretation of the failure Inspection from the opposite flanges showed forks close to the ferrite holder in both scanners The V1 was rubbing against the ferrite holder. All available hours were spent adjusting the fork positions. Some improvement, but situation still not optimal The system of ferrites and holders were retro- fitted to the original LEP design for LHC operation The clearance between fork and ferrite holder is too small for the alignment precision that can be achieved with the mechanics 1.5 – 2 mm nominal clearance between fork and ferrite holder Section, looking from beam axis showing fork and ferrites Photo of the scanner, showing ferrites (black) and clearance between fork and ferrite holder Origin of the problem: Contact between fork and ferrite holder R. Veness

TS1 (June) Curve intensity limits for ions New probing and logging of the potentiometer position G. Baud

from September… New web site… Easy debugging in case of problems Sigma calculation Bunch viewer Available for all the BWS A. Cudny – E. Piselli

To be done R. Veness Mechanics YETS : Upgrade of all four BWS on Beam 1, installing 8 new ferrite holders and new ferrites 2016 (surface activity) Re-machining of the removed ferrite holders EYETS : Upgrade of all four BWS on Beam 2, installing the 8 re-machined ferrite holders and new ferrites Status: Influence of the increase in slot size has been evaluated as negligible by ABP Agreed as important by LMC on 11/11/15, but still under discussion for VSC scheduling and parts availability

To be done G. Baud – J. Emery – E.Piselli Software New intensity limits for ions Took advantage to ensure checks are done even when “User” scan is triggered New “crosstalk” removal filter ( Based on Georges’ previous presentation ) Better noise filtering FESA code process review…detailed functional description (state machine block diagram)

Usage Statistics #week #scans B1H1B1H2B1V1B1V scans B2H1B2H2B2V1B2V scans

Thanks for you attention