Status & operational experience of Liberas at SSRF Leng Yongbin, Yan Yingbing, Zhou Weimin, Chen Yongzhong Ye Kairong, Yuan Renxian, Zou Yi, Yu Luyang,

Status & operational experience

of Liberas at SSRF

Leng Yongbin, Yan Yingbing, Zhou Weimin, Chen Yongzhong

Ye Kairong, Yuan Renxian, Zou Yi, Yu Luyang, Huang Guoqing

BI Group, SSRF2009-06-22

YAN Yingbing / SSRF BI group Libera Workshop, ESRF, Jun 2009

Outline

Introduction of SSRFSSRF BPM systemLibera applications

• Tune monitor• Beam spectrum monitor• Beam current & charge measurement• BPM phase advance monitor


Shanghai Synchrotron Radiation Facility

Third generation light source Total budget is about 130 millions EURO Started @ 12/25/2004 and is open to user @ 5/1/2009


SSRF complex


Libera based BPM system


Specification


BPM system overview

Components Solution Producer

Pickup Stripline @ injector

Button @ ring

Customer design, local company

Customer design, Kyocera, Japan

Cable Major cable, SMR400

Jumper cable, SMR240

Field fabricated, Times microwave

Prefabricated, Times microwave

Processor Libera electron IT

IOC software DLS package Diamond Light Source

Group access Soft IOC, EPICS DB chain

Customer design

High level application

Matlab, LCA

Soft IOC analyze package Customer design


Ring pickup factory test

Mechanical inspection DC isolation resistance

Capacitance

Magnetic permeability

AC voltage break down

Network analyzer S11

Leakage

BPM block gauge


Ring pickup factory test

Measurement Results

-2.5

-2

-1.5

-1

-0.5

0

0 5 10 15 20

Frequency [GHz]

Ret

urn

Lo

ss [

dB

]

Sample1_1Sample1_2Sample2_1Sample2_2Sample3_1Sample3_2Sample4_1Sample4_2Sample5_1Sample5_2Sample6_1Sample6_2Sample7_1Sample7_2Sample8_1Sample8_2Sample9_1Sample9_2Sample10_1Sample10_2Sample11_1Sample11_2

Step Response(~20GHz)

45

46

47

48

49

50

51

52

0.08 0.09 0.1 0.11 0.12 0.13 0.14 0.15 0.16 0.17 0.18 0.19

Time[ns]

Oh

m

Sample 1_1Sample 1_2Sample 2_1Sample 2_2Sample 3_1Sample 3_2Sample 4_1Sample 4_2Sample 5_1Sample 5_2Sample 6_1Sample 6_2Sample 7_1Sample 7_2Sample 8_1Sample 8_2Sample 9_1Sample 9_2Sample 10_1Sample 10_2Sample 11_1Sample 11_2

系列23


BPM station 5

ID BPM

Blue line 30m, redundancy for installation 20m The longest cable should be shorter than 30m + 20m = 50mTotal insertion loss < 0.1 * 50 + 0.5 + 0.5 = 6dB

Major cableTIMES LMR400Loss < 10dB/100m

Jumper cableTIMES LMR240Total loss < 0.5dB

BPM cabling


BPM cable & processor installation


BPM data & functions ready for accelerator physicists

Support by DLS package• ADC raw data @ 117MHz, 2048 points• First turn data synchronized by injection trigger• First 2048 samples of TBT data synchronized by injection trigger• Up to 0.5M samples of TBT data on demand• 10Hz SA data, orbit measurement • Embedded position interlock logic• User defined current scaling factor (beam current measurement)

Instrumentation Technologies delivered • 10kHz FA data @ SFP port

SSRF added some applications• 24 hours buffer for SA data @ EPICS DB level• Auto Gain Control logic (1Hz) @ EPICS DB level• Beam lifetime measurement @ EPICS DB level• Phase advance measurement @ EPICS DB level


Current performance

•No obvious critical narrow band noise below 100Hz•Integrated noise @ [0 1kHz] smaller than 1um•Could be improved by identify & remove unknown noise source

101

102

103

104

10510

-3

10-2

10-1

100

101

Frequency(Hz)

Am

plit

ud

e (

um

)

Integration noise @ 146mA, 2009.05.31

Electronics, 10BPM5Y plane, 15BPM8X plane, 15BPM8


Ring BPM resolution

0 20 40 60 80 100 120 140 160 180 2000

0.2

0.4

0.6

0.8

1

Beam current (mA)

BP

M r

esol

utio

n (

m)

SSRF Ring BPMs resolution test @ 2009.03.31

Average of all 140 BPMs

0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.40

5

10

15

20

25

30

BPM resolution varation (m)

Cou

nts

SSRF Ring 140 BPMs rms noise histgram @ 0.2mA

0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.650

2

4

6

8

10

12


Cou

nts


0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.80

2

4

6

8

10

12

14


Cou

nts


0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10

2

4

6

8

10

12

14

16


Cou

nts


0.2mA 1mA 10mA 200mA

COD resolution, BW 2Hz TBT resolution, BW 350kHz

0 20 40 60 80 100 120 1400

40

80

120

160

200

240

BPM index

BP

M r

eadi

ngs

ST

D (

nm)

@ 1

0Hz

Ring BPM resolution test @ 202mA top-up operation

10BPM3

10BPM1

08BPM3

14BPM7

16BPM5

10BPM5, electronics evaluaiton setup

2009.04.16

COD resolution @ topup operation

COD resolution: typical <200nm, best <80nm, with ideal beam <40nmTBT resolution: typical 3umUniformity of filling pattern is important for BPM performance


Beam current dependency (1)

100 110 120 130 140 150 160 170 180 190 200 210-0.06

-0.04

-0.02

0

0.02

0.04

0.06

0.08

Beam current (mA)

BP

M r

eadi

ngs

drift

(m

m)

BPM current dependecy test during injection @ 2009.04.13

100 110 120 130 140 150 160 170 180 190 200 210-5

-4

-3

-2

-1

0

1

Beam current (mA)

BP

M r

eadi

gs d

rift (

m)

BPM beam current depedency test @ 2009.04.13

Evaluated BPM: 10BPM5

"ideal beam" signal from 1to4power splitter link to on button

Data acquired during injectionabout 15 minutes

Evaluated during injection (15minutes)

BPM readings drift including: electronics BCD&FPD, BPM block drift, orbit driftMore than 90% drift within 20um, few BPMs drift up to 70um @ [100mA 200mA]

Electronics BCD&FPD only: within 5um @ [100mA 200mA]

Reference BPMNormal BPMs


Beam current dependency (2)

Evaluated during decay (2.5 hours)

BPM readings drift including: electronics BCD&FPD, BPM block drift, orbit driftMore than 90% drift within 10um, few BPMs drift up to 30um @ [170mA 200mA]

Electronics BCD&FPD only: within 1.5um @ [170mA 200mA]

170 175 180 185 190 195 200 205-30

-20

-10

0

10

20

30

40

Beam current (mA)

BP

M r

eadi

ngs

drift

(m

)

BPM current dependency test during decay @ 009.04.14

3 hours

170 175 180 185 190 195 200-1.6

-1.4

-1.2

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

Beam Current (mA)

BP

M r

eadi

ngs

drift

(m

)

BPM beam current dependency test @ 2009.04.14

Evaluated BPM: 10BPM5

"Ideal beam" signal from1to4 power splitter link toone button

Data acquired during decayabout 2.5 hours

Normal BPMs Reference BPM


Filling pattern dependence (1)

0 2 4 6 8 10 12 14-0.35

-0.3

-0.25

-0.2

-0.15

-0.1

-0.05

0

0.05

Time (minutes)

BP

M r

eadi

ngs

drift

(m

m)

BPM filling pattern test @ 10mA, 2009.04.30

2

4

8

16 32 48



0 50 100 150 200 250 3000

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

Bunch ID

Bun

ch c

harg

e (n

C)

BPM Filling pattern test @ 2009.05.01

Topup refill

Original fill

0 20 40 60 80 100 120118.8

119

119.2

119.4

119.6

119.8

120

120.2

120.4

Time (minutes)

Bea

m c

urre

nt (

mA

)

BPM filling pattern dependence test @ 2009.05.01

0 20 40 60 80 100 120-12

-10

-8

-6

-4

-2

0

2

4

6

Time (minutes)

BP

M r

eadi

ngs

drift

(m

)


Y plane, 10BPM1X plane, 10BPM1

0 20 40 60 80 100 120-40

-35

-30

-25

-20

-15

-10

-5

0

5

10

Time (minutes)

BP

M r

eadi

ngs

drift

(m

)


Y plane, 10BPM4X plane, 10BPM4

No evidence showed that BPM readings jumped due to filling pattern changing



No evidence showed that BPM readings jumped due to filling pattern changing

Original fill

refill


Libera application


Tune monitor configuration

Configuration is the same for Booster and Ring


Tune monitor performance: Ring

Daily operation:FFT of 10k TBT data, uncertainty < E-4

Precise measurement: FFT of 400k TBT data, uncertainty < E-5

Typical TBT data during tune measurement

Precise tune measurement

Daily operation panel


Tune monitor performance: Booster

TBT data 400k samples, cover 240msFFT windows size 2048, 1/1.23ms = 800HzTune measurement uncertainty < E-3

Horizontal ramping tune Vertical ramping tune Tune drift during ramping


Beam spectrum monitor (TBT)

Current dependent few tens Hz noise @ copper cavity running. Gone with copper cavity


Beam spectrum monitor (TBT)

Observed 15Hz & 46Hz noise, PS group targeted the source based on this information


Beam spectrum monitor (10Hz)

0.1Hz, 3.1Hz and 4.5Hz noise observed, still working to identify the source


Beam current & charge measurement

Libera could be used to measure beam current, data rate usually is better than PCT system. ButOrbit offset adjustment should be applied.RF frequency adjustment should be applied.Current scale factor (KI) and current offset should be precisely calibrated with PCT one by one. It’s easy to do when machine running with fixed orbit. If orbit moving it will be very complicated.

BI group SSRF, Feb 2008

Beam arrival monitor

Injected beam First turn

Multi turns Stored beam

Sum signal of first turn, calculated from ADC data Bad cable connection, or huge orbit offset

SSRF, Feb 2008

Beam current measurement @ ring

0 10 20 30 40 50 60 70 80 90 100

10-1

100

101

Beam current (mA)

Cur

rent

rea

ding

err

or (

muA

)

Libera current measurement test @ 2009.02.18

NPCT175 + 5.5 digits DVMSingle libera readingsAverage of 140 libera readings

0 50 100 150 200 250196.8

197

197.2

197.4

197.6

197.8

Time (s)

Bea

m c

urre

nt r

eadi

ngs

(mA

)

Libera current measurement @ RF variation, 2009.01.02

Libera readingsNPCT readings

All Liberas averageRF frequency changed from499.6725MHz to 499.6735MHzand back to 499.6725MHz

Current resolution test RF frequency dependence observed

Orbit dependence observed

Current resolution is better than PCT @ [0 50mA]

Current measurement error 0.2% due to RF change

Up to 2% current error due to orbit move


BPM Phase advance monitor

The phase difference between two neighboring BPMs can be calculated

Cell 1


Acknowledgment

Guenther Rehm and Micheal Abbott from DLS

Jean-Claude Denard from Soleil

Jim Sebek and Bob Hettel from SSRL, SLAC

Documents

Status & operational experience of Liberas at SSRF Leng Yongbin, Yan Yingbing, Zhou Weimin, Chen Yongzhong Ye Kairong, Yuan Renxian, Zou Yi, Yu Luyang,