Linac4 FBCT’s

Linac4 FBCT’s

18/10-2011 1L4 BI BCT review Lars Søby

On the behalf of: M. Andersen, D. Belohrad, L. Jensen, Franco Lenardon and J. C. Allica Santamaria

http://linac4.web.cern.ch/linac4/Default.htm

BCT’s in the Linac

Ø= 100 mm

Ø= 146 mm

18/10-2011 2

* 6 for L4T, L4Z

11 BCTS in L2

L4 BI BCT review Lars Søby

Transfer Line

H- sourc

eLEBT RFQ

MEBT (chopper

)DTL CCDTL PIMS

Dump Line

L4L ~ 12 m L4D ~18 m L4C ~22 m L4P ~14 m

L4T ~50 m

L4Z ~10 m

Ø= 100 mm Ø= 26 mm

Ø= 40 mm Ø= 40 mm

BCT Ø= 67 mm

Movable test bench


BCTs in Transfer line, Ø=100mm

BCT IN dump line


L4T.BCT.0107

L4T.BCT.0673

L4T.BCT.1043

L4T.BCT.1243

L4T.BCT.1553

L4Z.BCT.0293

1 BCT per 10m

From MovableTest bench Ø=67mm, DN63

From MovableTest bench Ø=67mm, DN63


Inter-tank transformers

BCT length 40mm

18/10-2011 4

Total length 146 mm


Total length 210 mm

BCT length 105 mm

CCDTL-PIMSDTL-CCDTL

Ø= 40 mm

Ø= 40 mm


Chopper line transformer

Ø= 26 mm

18/10-2011 5

EMC test has been doneIn place with quadrupoles pulsing with up to 250A. Perturbations less than 1% in window of 750us.

Quadrupole


VITROPERM 500 F µr> 10 000


LT.BCT30 (LINAC2) Transformer

Length 297mm

Diameter 146mm


6 BCTs in LT,LTB and measurement lines5 in BI line


50 or 20 turns?

20 turns with positive feedback

All BCTs as from second chopper line BCT must be equipped with 20 turns, in order to acquire short beam pulses. The second Chopper line BCT should be re-wound as well as the two from the movable test bench.

Pulse length=100ns2.5 more signal


50 turns without positive feedback


Linac 4 – RFQ pulse

Beam outof RFQ

Bunch spacing = 2.84ns

Bunch population : 1.14x109 H-

Linac4 pulse length = 400ms



Linac 4 – Chopped beam

PSB Trev = 1ms

• Total 352 buckets

• Max 222 buckets filled (630ns)

• Min 17 buckets filled (50ns)

• Multiturn injection : 1 up to 100 turns per ring

• Different chopping schemes

Pulse length = 400ms


Min 50ns

2.84ns

BCT response


Acquisition system


Rf

100-200m of cable

VME based TRIC card

Low pass filter on CH2

CH1: Fast relative current evolutionCH2: Average charge with time,CH2: Total charge in 400us pulse

CH1

CH2

All BCTs on OASIS


TRIC card

18/10-2011 L4 BI BCT review Lars Søby 11


TRIC specifications



TRIC measurement, L4 3MeV


Beam Beam offset Calibration Cal.offset

Non chopped beam



TRIC measurement, L4 3MeV

Different time scale



TRIC measurement, Lab

400us, 50ns chopped beam

BCT + H.E. + 100m cable + TRIC


TRIC measurement, Lab


BCT + H.E. + 100m cable + TRIC

400us, 50ns chopped beam


Digital integration error


So to do the digital integration we need ~100 (50) samples i.e. 500ns (250ns) pulses to have an error <1% or introduce filtering with ~ 1MHz LP filter.


Digital integration error


TRIC card 200MS/s

Oscilloscope 10GS/s


BCT and TRIC performance

Pulse length BCT Current BCT Charge TRIC Charge

Short cable

900ns 100 % 100 % 99.5%

800ns 100 % 100 % 98.7%

700ns 100 % 100 % 97.5%

600ns 100 % 100 % 97.0%

500ns 100 % 100 % 96%

100ns 100 % 100 % -

50ns 91 % 100% 60%

Long cable (200 m)

500ns 98 % 100% -

100ns 86 % 100% -

50ns 77% 100% -


So the error on the integrated charge depends on the TRIC card number of samplesOnly, while the current measurement is limited by the BCT bandwidth.


Specifications and performanceRequirements Performance of cable + TRIC

Pulse length 50us-400us 50 (500)ns-400us

Intensity range 10-80mA 10-100mA

Resolution 0.5mA 100uA (10 bits)

Accuracy 1% 1% after 800ns

Precision <0.5% (<0.5%)

Time resolution 1us 10ns-2us

Bandwidth 1Hz-6MHz 1Hz-6MHz

Droop at 1ms 0.6%

Observable Fast current with time, Ch1

Observable Total charge, Ch2

Observable Slow charge with time, Ch2



Total charge / Charge per ring


Transfer Line

H- sourc

eLEBT RFQ

MEBT (choppe

r)DTL CCDTL PIMS

Dump Line

L4T ~50 m LT, LTB transfer Line

R1 R2 R3 R4t

400us

Total charge for full pulse length

BIi.BCT20 BRi.BCT8L1

BI.BCT10

Total charge per ring

BI transfer line


Watchdog hardware


Four separate low loss and high loss WD’s

2ms

By user and destination, i.e we can continue sending beam to the Booster if losses in e.g. LBS


Watchdog



Watchdog hardware

• The WD uses TRIC cards to measure the intensity

• Both cards are connected by DVI connectors.

• Input Signals:– Intensity from TRIC– Screens in/out: Indicates

allowed loses.– Bending magnet status:

indicate if beam is expected

– Triggers: No trigger no beam

– Remote Reset: Reset the WD when has been triggered


BeamPermit2ms


Watchdog


Watchdog BCT Destination action inputs outputs

LOW ENERGY3MeV Test stand

L4L.BCT.1183

all No beam permit if

transmission in # of charges is below set

threshold

3 MeV BIC, ‘RFQ watchdog

’ user input

L4L.BCT.3113

Linac4L4L.BCT.3113

all No beam permit if current is below hard-coded threshold

Stop and start pre-chopper timing

signals

Master BIC

‘source RF’

fixed threshold

GENERAL

Linac4 and L4T

L4L.BCT.4013 L4DUMP

No beam permit for specific user if


threshold

Destination + user

information from MTG

Master BIC ’L4 &

LT OK'

L4Z.BCT.0117L4L.BCT.4013

LBE, LBS, PSB LT.BCT30

Master BIC ’L4 &

LT OK'LT/LTB/BI,

LBE/LBS

L4T.BCT.1553 PSBBI.BCT20.SL4T.BCT.1553 LBE LBE.BCT65L4T.BCT.1553

LBSLBS.BCT64

PSB INJECTIONBI.BCT20.S

PSB BIC ‘PSB ok (1)’∑ of 4 BCTs in PSB

section 8L1

HIGH LOSS

Linac4 and L4T

L4L.BCT.4013 L4DUMP

No beam permit for specific DESTINATION if


threshold

Destination + user

information from MTG

Master BIC ’L4 &

LT OK'

L4Z.BCT.0293L4L.BCT.4013

LBE, LBS, PSB lt.bct30

LT/LTB/BI, LBE/LBS

L4T.BCT.1553 PSB Master

BIC ’L4 & LT OK'

BI.BCT20.SL4T.BCT.1553 LBE LBE.BCT65L4T.BCT.1553

LBSLBS.BCT64

PSB INJECTIONBI.BCT20.S

PSB BIC ‘PSB ok (1)’∑ of 4 BCTs in PSB

section 8L1


Planning

Transformer Drawings completed

Manufac. Tested Installed Head amplifier

TRIC card Watchdog Sparevacuum chamber

Diameter

LEBT1+1ps

1 OK1

underway

To be odered

100 mm

Chopper line2

December 2011

June2012

26 mm

Line 3 MeV2

December 2011

To be ordered

67 mm

DTL-CCDTL1pc

December 2011

December 2011

To be ordered

June2012

40 mm

CCDTL-PIMS1pc

May2012

December 2011

June2012

40 mm

L4T+L4Z6pc

June2012

December 2011

To be ordered

2 * 67mm4 * 100mm



Budget: 64371

2008 2009 2010 2011 2012 2013 2014

Budget 34715 93701 71403 79678 64671 42137 3694

Spent 1470 65000 52000 115000

18/10-2011 27

Left : 100kCHF

Item Cost Comments

4 L4T, L4Z BCTs 160kCHF

Cables L2 BCT 25kCHF Must go to BOR

L2 +BI TRIC 25kCHF New ACQ system

Extra LEBT BCT

Future costs

>110kCHF missing, mainly 2012!!



2011 2012 2013 20142010

Milestones


Linac4 installation & commissioning

nov-10

jun-11

jul-12

jan-13

apr-13

feb-14

Start of Cabling campaign

Start of Machine installation

Test Stand move to Linac4

Start of intermediate Beam Commissioning

Start of Linac4 Beam Commissioning – 160MeV

Start of General Services Installation20 months

12 months

9 months

4 months

10 monthsCritical Path


Conclusions Everything on schedule Over spending by ~110kCHF , one extra LEBT BCT. A total of 22 BCTS……. 20 turns on all BCTs…also chopper line BCT and

movable test bench. Foreseen when moved to L4. Fast current measurements limited to 500ns beam

pulses, due to BCT bandwidth. Charge measurement to 1% requires 50-100 samples

~800ns pulses. Improve firmware and/or introduce filter on TRIC CH2 with total charge measurement.

Viewing of pulse shape on TRIC CH1, and OASIS. Total charge per pulse in L4 + transfer lines. Charge per

ring in Booster injection region.



Linac4 FBCT’s

Documents

Transcript of Linac4 FBCT’s