PS and East Area re-commissioning with beam from the CCC after a 17 month shut-down R. Steerenberg with help of many colleagues from different groups PS

PS and East Area re-commissioning with beam from

the CCC after a 17 month shut-down

R. Steerenbergwith help of many colleagues from different

groups

PS - SPS-Days

19 January 2006

PS - SPS-Days

19 January 2006

PS - SPS Days 18 January 2006R. Steerenberg 2

Topics:Main Magnets renovation and realignment PS inflector zoneMPS and B-trainsRF issuesInternal dumpsPS trajectory and orbit measurement (CODD)Extraction bumps TT2 realignment and low beta insertion modificationsSlow Extraction and East AreaOctupolesControl system and SoftwareOther important changesSchedule and rough planningRequest for support form all groupsConclusions


PS Main Magnet Revision25 Main Magnets are renovated and re-installed:All magnetic polarities of each circuit will be measured in the ring.Cabling errors can lead to two main problems:

One inversion early in the chain Easy to detect as the optics is very different for required current.Two inversion not too far separated from each other Optics wrong by a percentage which is equal to twice the number of magnet that have the wrong polarity.

Difficult to detect and long search necessary to locate wrong connections.If not detected this will limit the machine performance

CODD and tune measurement are necessary !!!

Are the new PFW’s identical to the old ones ?


Ring realignment (1)

About 20 years ago, 10 main magnets were voluntarily displaced up to several mm to correct the orbit at ‘high’ energy.5 in the horizontal plane5 in the vertical planeAt present the main magnets will be realigned along a smooth curve with fixed points at the injections (26, 42) and extractions (16, 61), taking out these voluntary misalignments.During the start up with beam the ‘High’ energy orbit will be re-corrected using the same method.


Ring realignment (2)

Orbit measurements will be made at ~10 GeV/c.

New corrections will be calculated and magnets will be voluntarily displaced to re-correct the orbit.If the magnet needs to be displaced by more than 0.5mm (very likely) we have to break the vacuum.Local displacements can be made at a rate of 3 magnets per day.This means 3 to 4 days work depending on the amount of magnets concerned.

Since this consumes quite some start up time, we hope that one iteration will be enough.


PS Inflector zoneThe PS inflector zone was built to be able to continue running the PSB while accessing the PS straight sections 0 to 17 and 41 to 99.At present it is not possible to close the inflector zone rapidly during the machine run in case of a problem or work in the PS.This may lead to loss of valuable start-up, Physics or MD time.The first case is the displacement of the main magnets for the correction of the PS ‘high’ energy orbit.

Preliminarily planned for week 17.PS access is necessary.Might last for more than a week.Coincides with first week of ISOLDE physics.


When PS was stopped in 2004 there was a problem with the MPS regulation.Solution to the problem is found and implemented

Fine adjustments to be madeOn-line test to be performed

If not all our cycles and optics need to be modified

B-train responsibility will be transferred from AB/PO to AT/MTM

AT/MTM has no piquet service, but will provide a specialist service.What when specialist cannot be reached ?

FMR system, for diagnosing B-train problems, is under revision, to improve remote use.Should be available at start up.

MPS and B-trains


200 MHz cavitiesThese cavities are used for longitudinal blow up at different energies and for applying a 200 MHz structure on the Fixed Target beam for the SPS.

Initially 8 cavities:6 cavities in SS06 (non tuneable)2 cavities in SS08 (tuneable)

Cavities in SS08 will be removed, we will only have 6 cavities in SS06.

New configuration:C201, C204, C205, C206 (non tuneable)C202, C203 (tuneable)

Cavity controls and matrix application need to be modified.


Beam Control issues

Control of the phases for bunch splitting and re-bucketing are now remotely available. to be tested

Many RF by-passes are dismantled and reinstalled during the magnet renovation project. They should be carefully checked.

In 2004 the RF by-pass of SMH16 had a bad contact and this made that the current in the first quadrupole in the TT2 line was heavily perturbed.


Internal DumpsCaused many problems last years, but …

Both dumps are renovated and should be reinstalled one of these days to be available at the start up.

New power supplies are installed on the surface and not next to the dumps as in the past.

The system was tested outside the tunnel.

Preparations for new controls have been made.

Old controls will be used during 2006.

If the dumps do not work, setting up will be more difficult.


CODD pick upsNew head amplifiers have been installed to measure also ions down to 1E9 charges per bunch (was 1E10).Many efforts went in to reducing the noise levels, by using new design and better shielding.For all gains the displacement sensitivity is 40mm (was mixed: 20mm and 40mm).The gain curve is much more linear with only maximum 0.5 dB error (was 10 dB)RT task will be adapted and as a consequence the CODD application needs to be modified.


CODD pick ups

Old system New system, still some gain to spare

Courtesy of J. Belleman

Laboratory measurements show the improvement

New calibrations will have to be done CODD is one of the first system that is needed for a good start-up

Will it be available on the 1st or 2nd day ?


Bump 16Consists of 4 magnets connected in Series-Parallel: (SS12-SS22)||(SS14-SS20)

To prepare future Multi-turn Extraction the bump needs to be modified. First step:

SS Old type

New type Comment

12 206 205 Spare

14 210 205 Spare

20 206 205 from DHZ60

22 210 205 From SS35 of BSW31Magnetic differences are negligible.

PO will check regulation.


Bump 31Consists of 2 magnets connected in Series: SS27 and SS35

Will be eliminated in future for new Multi-turn Extraction, but for 2006 it will be:

SS Old type

New type Comment

27 205 210 From SS22 of BSW16

35 205 205 Remains unchanged

Magnetic differences are negligible.

PO will check regulation.


TT2 line: RealignmentTT2 is realigned taking in account the available correctors.

Courtesy of M. Martini

New steering to be found, only few correctors available…..

m

mm


TT2 line: Low beta insertion4 new quadrupoles are added, which should have zero current for proton operation.

F16.QDE163, F16.QDE207, F16.QDE213, F16.QDE217

First 2 quads from each string are separate now.

F16.QDE210s consisted of 14 quads and became now:F16.QDE210 (1 quad with separate power supply)F16.QDE220s (13 quads in series on 1 power supply)

F16.QFO215s consisted of 13 quads and became now:F16.QFO215 (1 quad with separate power supply)F16.QF0225s (12 quads in series on 1 power supply)

For proton operation the quads should have the same currents as before (2004), values will only be different for future ion operation.

Magnetic polarities should be checked.


Slow Extraction1 sextupoles in SS7 and 2 in SS19.For the future Multi-turn Extraction the vacuum chamber in SS19 needs to be enlarged.The sextupoles in SS19 need to be moved to SS03.Both quadrupolar pick-ups SS03 and SS04 will be removed. Wall Current Monitor SS03 remains.In 2006 we will have:

1 sextupole in SS7 (remains as it was)2 sextupoles in SS19 (will be removed in 2007)2 sextupoles in SS3 (future SE configuration)

This year we should make the new configuration work, otherwise we need to construct 2 new large aperture sextupoles for SS19.


F61S.BHZ01: a new magnet with improved cooling system will soon arrive and will be installed before the start up.

F61S.QDE02, F61N.QDE01 and QFO02New magnets are under construction, but delivery date is still uncertain.If not in time run with present magnets and their problems.

ZT7.QFO01 and ZT10.QDE01are or will be changed before the shut down.

The MNP23 in T9:Had an earth current problem, probably due to conductivity problem in cooling water. No spare magnet available. If problem persists the beam line will run with lower energy !!!

East Area (1)


Is the cause known ?This cannot be confirmed nor excluded.Conductivity measurements system broke down in 2004 no systematic measurements.Could be due to demineralisation modules.

Is the problem solved ?The measurement chain is repaired and recalibrated.demineralisation modules will be changed systematicallyAn additional off-line measurement system is put in place.

East Area Cooling water


OctupolesIn 2006 there will be 6 octupoles out of originally 8 available for adding Landau damping in the transverse plane.

This should be no problem:Instabilities are better under control without using octupoles.

More than enough power available with remaining octupoles


Control system and SoftwareThe PS complex will restart using the applications that were used in 2004.

The existing diagnostic tools will be supported, new ones will be coming.The Oasis observation system will be used, not Naos.The PS ‘MD’ signals will be on Oasis too. Very limited FESA implementation nevertheless means that we will have to use two alarm trees in parallel. less convenient, risk of incoherence ?!

TT2, Inj. 26 and AD beam screens (MTV’s) VOS application has been modified to be able to control GM and FESA MTV’s, using knobs.

However, FESA MTV alarms, like “screen in” will not appear in the X-motif alarm tree.


Other important changesThe PS telegram is now send every basic period instead of every cycle.

Front-ends adapted to see only first telegram of a cycle, to avoid problems with RT-tasks.Workstation always received a telegram per basic period via the network.

Technical Network is now isolated from General Purpose Network. Access can only be done with trusted machine or via a terminal service.

What will the impact be for access to machine parameters from other places than the CCC.


Schedule

A thorough cold check-out reduces start-up problemsSet up and make the beam go aroundCope with realignments and changesSet up beams for users:

SFTPRO / CNGSADEast AreaLHC beams (Pilot, 25ns)


Rough planning

A more detailed planning of both the cold check-out and start-up with beam is being made.Check list and procedures will be in the CCC.


SupportWe ask all the groups to test and debug their equipments and systems as much as possible well before the Cold Check-Out.Measurement and diagnostic systems are necessary to set up the beam and it should not be the other way around. CO will provide a piquet service as in 2004. Two people during day for start up.OP will be in the CCC:

We will have the same level of control as in the MCRAll diagnostics tools and signals will be availableHowever, we cannot intervene locally on equipments as we did from MCR.

This means that the first line or equipments specialists will be asked more frequently to intervene on their equipment.


ConclusionsThe list is not exhaustive and all additional information is very welcome.Many changes have been made, of which some might cause trouble during the start up.Ring realignment and orbit correction is a time consuming work (magnet movements and perhaps bake-out)There are no real show stoppers at the horizon, but we are never 100% sure.....

The 2006 start-up will be challenging for many reasons, but by continuing to put all

efforts and goodwill in, together we will make it work again !!!

Documents

PS and East Area re-commissioning with beam from the CCC after a 17 month shut-down R. Steerenberg with help of many colleagues from different groups PS