PLS Operation and The Tools
E. S. Park, Eun-Hee Lee, Mun-Gyung Kim
S.-H. Shin, Sung-Ju Park And Kyung-Ryul Kim
WAO2010
Daejeon, April 12- 16, Korea

Talk about- PLS- PLS II- Accelerator Model- Case of Application

Aerial view of PLS

History of PLS
 Project started

Apr. 11988

 2-GeV PLS Commissioning

Dec. 241994

 User Service Start

Sept. 11995

 2.5 GeV Ramping

Sept. 12000

 2.5-GeV Injection

Nov. 1

2002

 TOP-UP operation

September2010

July2011

 PLS-II Project (3 GeV )CommissioningPLS( Pohang Light Source)
Storage Ring

Linac Beam Energy

2.5GeV Frequency
2,856Mhz
Energy Spread Number of Klystrons Beam Energy

2.5GeV Beam Current

190 mA Lattice

TBA Period12

 Circumference

280.56 m

0.26%
12

 No. of Acceleratingcolumns44

 Emittance

18.9 nm-rad Total Length

160M

 Tune14.28 / 8.18

Beam Lines in Service(2 0 Bending +8C2

8A1

8C1

7C

7 ID Beamlines)

7B1
6C1
6B

10C1
5C2
5C1

StorageRing

ID beamline
Bending Magnet
beamline

5A
4C2
4C1

11B

4B1

1B22A

2B1

3A1

SourceMinimum
Gap

2A

EPU (EPU6)18 mm

3A1 / 3A2

Undulator (U6/ U10)

4A

Wiggler(MPW14)8mm Fixed

5A

Wiggler(MPW14)8mm Fixed

8A1 / 8A2

Undulator (U7)

20 mm

11A

Revolver(Revolver)

6 mm

9A

IVU

Not installed

10A

Wiggler(MPW10)

Installed, notused

7B29C

11A I

Beamline

3A2

4A
3C2
3C1
3B1

Operational Statistics: User Service Rate
Lifeimte (hr.)

Service Rate

240

120

200

100

160

80

120

60

80

4040

20001995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009Year

Lifetime (hr.), Service Rate (%)

Cuurent (mA)

Current (mA)

PLS II
Parameter

PLS

PLS II

Beam Enegy[GeV]

2.5

3.0

Beam Emittance[nm·rad]

18.9~5 - 10

Stored Beam Current[mA]

200400Total Number of IDs

1020

Lattice

TBA /12 Cell

DBA /12 Cell

Operating Mode

Decay /Topup/

Topup

Brightness~2 x 1018~1020*RF Cavity

Conventional

SC Cavity*Bending Magnet Type

Separated

Combined

Circumference[m]280.56281.82

In Dreaming of PLS II Control Room

Accelerator Model of PLS

How do you know which part of thisfile should be rewritten?

A file of PLS magnet settings consistsof 300 elements

Modeling of Accelerator

1987

V = M · dU: ModelingdU = M-1 · V: Inverse Modeling
V : Beam Parameters
U : Strengths

6543

M_designed

2

M_measured

COCU (Closed Orbit Correction Unit)
Developed at CERN)- Global Correction :- Local Correction :MICADOBUMP4SThe Phase advance of T used in COCU
(Calculated using MAD8 in 1998)
HorVer- Model(COCU) Tune

- MeasuredTune(14.28 / 8.18)(14.26 / 8.20)

MML : PLS Modeling

Model Tune
(14.407 / 8.487)
Measured Tune
(14.26 / 8.20)

Correction of Mmeasured with MML

Typical Startup Procedure
after a long Shutdown
1. Orbit Determination after Summer Maintenance- Previous corrector settings do not work2. Local Correction for Beamlines- Photon beams to be steered locally

3. Keep Orbit Stability in User Service- Tunes should be kept around (14.28, 8.18)

Unusual Consequences
Why is the stored beam is killed by the operation of the kicker
magnet?
100 ms

100 ms

100 msNormal Case

100 msLifetime of stored one bunch

6 hours later

One bunch, but remained stable

Time structure

T1
P12CH6T2
6 μsecP01CH3

Test of what conditions make the bunch survive
1. Change the storage ring corrector from -35A to 20A, covering
maximum kick angle.
2. Change the timing of two bump kicks by inserting cables, whose timedelays are from 5ns to 30ns, respectively.
3. Test- From the kick of 2kV the upstream corrector range was narrowed.
- At -8.0A setting the bunch was safe from the kick of 6kV.
4. Result
The injected bunch could be safe always if the kick power would beremained under 6kV.

5. But with this kick the Linac Beam could not be injected into. A great
shortcoming!

Table showing the Bump Kick verse SR corrector kick
P12CH6 Corrector SettingKicker-8.0A(Stored orbit Current)

-35A

2,000

20A
alive

slow loss
4,000 alive

alive

4,500 alive

alive

5,000 alive

alive

5,500 alive

very slow loss

5,700 alive**6,000 alive
6,300 alive

6,700 slow loss
7,000
7,200 loss within 1~2 sec
7,500
8,000 quick loss
15,400quick loss

quick loss

Need a local bump
generated by an upstream SR correctors
Normal postion ofSide view

Injection fromLinac

Stored orbit
Temporary Orbit

Bumped orbit
P12CH6Plan view

P01CH3

Kicker Strength verse Bump Height
While changing the time delay of two kicks It was possible to savethe stored bump with the reduced powers of 6kV from 15.4kV.
Distance
between Kicker
1260
1260

Kickervoltage
5000
5500

1260
1260
1260
1260
1260
1260
1260

6500
7000
7500
8000
10000
12000
15400

1260

6000

0.003865
0.0042515

Bump
height(mm)
4.870
5.357

Kickerlength(mm)600
600

0.0050245
0.005411
0.0057975
0.006184
0.00773
0.0092760.0119042

6.331
6.818
7.305
7.792
9.740
11.68815.000

600
600
600
600
600
600
600

angle(rad)0.004638

5.844

600

Getting to be accumulated without loss

Not killed by the next kicks

The reference orbit was restored to the normal reference orbit

A snapshot of Web-based monitoring software on March, 27.

In Conclusion
such that dU = M-1 · V
where U is the required strengthand V is the desired Orbit.
and Mmeasured work well.

- PLS has Mdesigned- Mdesigned- Matlab-based code MML will be in active
to develop the Mcalibrateded
and adjust the quadrupole strengths using this Mcalibrateded.
This MML with COCU could bea great help to the operation of the PLS II.
Thank you!

AndWelcome to PLS !