lead ion tests in lear ppc - 19 septembre 1997 m. chanel

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LEAD ION TESTS IN LEAR • PPC - 19 Septembre 1997 M. CHANEL

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Page 1: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

LEAD ION TESTS IN LEAR

• PPC - 19 Septembre 1997 M. CHANEL

Page 2: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

PARTICIPANTS• D. Allen

• L. Badano

• D. Berlin

• J.L. Blanc

• J. Bosser

• B. Bouriquet

• H. Broere

• R. Brown

• C. Carli

• M. Chanel

• J. Duran-Lopez

• F. Formis

• A. Fowler

• H. Haseroth

• C. Hill

• S. Jacobsen

• C. Lacroix

• A. Lombardi

• R. Maccaferri

• P. Maesen

• S. Maury

• K. Metzmacher

• D. Möhl

• G. Molinari

• B. Moine

• H. Mulder

• F. Nanni

• M. O’Neil

• J.C. Perrier

• U. Raich

• S. Rossi

• E. Roux

• J. Sanchez

• R. Sautier

• E. Tanke

• G. Tranquille

• M. Vretenar

• et les autres

Page 3: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

LES MODIFICATIONS DE LEAR

The Lear machine layout in 1997

E-Coollong drift( 3m )

Fast Bump

ElectrostaticSeptum

The Lear machine layout in 1996

E-Coolshort drift( 1.5m )

Lear adapted for slow extraction

and jetset

Lear adapted for Multiturn injection and long ecool:-line transfo(2)-bumpers, move SEH-exchange s2/s3-ecool 3m drift-vacuum improvements

Page 4: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

The electron-cooling device in 1997

6

12

34

56

6

7

8

9

10 11

6

67

8

10

1213

1415

1617

9

1 Variable perveance gun2 Cathode3 Grid anode4 Ground potential anode5 NEG pump6 Solenoid7 Neutralisation electrodes8 Toroid chambers with pumps and diagnostic ports

9 Toroid NEG pumps10 Pick-up stations11 Central drift tube12 Collector drift tube13 Collector vacuum valve14 Collector entrance coil15 Repeller16 Collector17 Collector end coil

3.0 m

5

Longer, more negs, magnetic measurements, new controls, smooth continuous tube(no natural neutralisation)

Page 5: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Caractéristiques des Machines Machine 1

• Cooler: D=3.5m, h=1.7m, v=6.5m

• Injection:D=3.5m,h=1.7m, v=6.5m

Machine 97

• Cooler: D=0 m, h =5 m v=4.4m Injection:D=10 m, h =3.3m v=6.6m

Machine 4/96

• Cooler: D=0 m, h =9.5 m, v=7m

• Injection: D=0 m, h =9.5 m, v=7m

Page 6: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

LE REFROIDISSEMENTEN INJECTION MONOTOUR

• La charge d’espace

• Le cooling des grandes émittances

• les comparaisons des différentes machines

Page 7: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Charge d'espace pour Ie=288mA,machine 1,eps=50pi

-8

-3

2

7

12

17

-30 -20 -10 0 10 20 30

x[mm]

dp

/p

dp/pecool

dp/pmach

xeps-

xeps+

Page 8: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Charge d'espace pour Ie=288mA,machine 97,eps=50pi

-8

-3

2

7

12

17

-30 -20 -10 0 10 20 30

x[mm]

dp

/p

dp/pecool

dp/pmach

xeps-

xeps+

Page 9: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Charge d'espace pour Ie=288mA,machine 97-2,eps=50pi

-8

-3

2

7

12

17

-30 -20 -10 0 10 20 30

x[mm]

dp

/p

dp/pecool

dp/pmach

xeps-

xeps+

Page 10: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Charge d'espace pour Ie=288mA,machine 1, neutralisation 36%

-8

-3

2

7

12

17

-30 -20 -10 0 10 20 30

x[mm]

dp

/p

dp/pecool

dp/pmach

xeps-

xeps+

Page 11: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

TRANSVERSE COOLING OF LARGE AMPLITUDES

Charge d'espace pour Ie=288mA,machine 97,eps=50pi

-8

-3

2

7

12

17

-30 -20 -10 0 10 20 30

x[mm]

dp

/p

dp/pecool

dp/pmach

at beginning

after long. cool.

after transv. cool.

Page 12: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

MEASURED TRANSVERSE COOLING OF LARGE AMPLITUDESbeam partially kicked, Ie=120 mA, machine 1, ‘eps’=22 pi

• Top view longitudinal Schottky • Top view horizontal SchottkyT

i me [

160m

s to

t.]

dp/p[4%o tot]df/f[4%o tot]

Tim

e[16

0ms

tot.]

Pbrk09Pbrk09

Page 13: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

MEASURED COOLING OF A MONOTURN INJECTED BEAMIe=52 mA, machine 97

• Top view longitudinal Schottky • Top view horizontal SchottkyT

i me [

1 s

tot .]

Time[1 s tot.]

Tim

e[1

s to

t .]

pb97g03pb97g03

Page 14: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

MEASURED COOLING OF A MONOTURN INJECTED BEAMIe=52 mA, machine 97

• BIPMH: one measurement every 50ms

• here at 0, 200, 350, 1000 ms

• BIPMH:evolution of beam dimension

-20 -10 0 10 200

2

4

6

8

10

0 500 1000 1500 2000-2

0

2

4

6

8

10

12

40

50

60

70

80

90

100

-20 -10 0 10 200

1

2

3

4

5

6

7

-20 -10 0 10 200

1

2

3

4

5

-20 -10 0 10 200

2

4

6

8 [m

m]

sum

Time[ms]

pb97g03pb97g03

Page 15: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Machine 1-97 260mApbb013pbb013

• Top view longitudinal Schottky • Top view horizontal Schottky

Ti m

e [45

0ms

tot.]

Ti m

e [45

0ms

tot.]

dp/p[4%o tot]

Page 16: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Machine 1-96 256mA

pb96009pb96009

• Top view longitudinal Schottky • Top view horizontal Schottky

Ti m

e [40

0ms

tot.]

Ti m

e [40

0ms

tot.]

dp/p[4%o tot]

Page 17: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Machine 1-97 260mA better adjusted

pbb021pbb021

• Top view longitudinal Schottky • Top view horizontal SchottkyT

i me [

300m

s to

t.]

Ti m

e [30

0ms

tot.]

dp/p[4%o tot]

Page 18: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

MEASURED COOLING OF A MONOTURN INJECTED BEAM BY BIPM

compare BIPM machine1-97/machine1-96, Ie=260mA

0

2

4

6

8

10

12

14

0 100 200 300 400 500 600

t[ms]

[mm

]

machine1-97 x[mm]

machine1-96 x[mm]

compare BIPM machine97/machine4-96, Ie=200mA

0

2

4

6

8

10

12

0 200 400 600 800 1000

t[ms]

[mm

]

machine97 x[mm]

machine4-96 x[mm]

Compare.xlsCompare.xls PRELIMINARY

Page 19: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Comparaison ‘cooling rates’ 97/96

machine 1 ecool 3m,1.5m

0

1

2

3

4

5

6

7

8

9

10

0 50 100 150 200 250 300 350 400

Ie[mA]

1/th[s

-1]

machine1-97:1/th[ms]

machine1-96:1/th[ms]

machine 97 et machine4-96

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

0 50 100 150 200 250 300 350 400

Ie[mA]

1/th[

s-1]

machine4-96:1/th[ms]

machine97:1/th[ms]

Compare.xlsCompare.xlsPRELIMINARY

Page 20: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Comparaison de toutes les machines testées

0

2

4

6

8

10

12

14

0 50 100 150 200 250 300 350 400

Ie[mA]

1/th

[s-1

]machine 7-96 1/th[ms-1]

machine97:1/th[ms]

machine4-96:1/th[ms]

machine1-97:1/th[ms]

machine1-96:1/th[ms]

PRELIMINARY

Compare.xlsCompare.xls

Page 21: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

L’INJECTION MULTITOURS COMBINÉE

• Le Principe

• Le LinacIII

• Les bumpers

• Le résultat sur la machine 97

• Conséquences sur le vide

Page 22: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Le principe• Pendant la décroissance du bump, augmenter P du faisceau

injecté tel que le point d’injection reste le même (D grand).

Injection into machine 97 (dp/p from -1 to 3%o)

0

5

10

15

20

25

30

35

40

45

50

-30 20 70 120 170 220

t[s]

x[m

m]

bump[mm]

D dp/p[mm]

inj. point[mm]

Le septum

Compare.xlsCompare.xls

Page 23: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Le linacIII• Change the amplitude

of Tank 3.• Change the phase of

the Debuncher• All in 80 to 200 s

Phase debuncherTank3 amplitude

Linac3.pcxLinac3.pcx

Page 24: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Les bumpers

• 4 bumpers with 4 individual power supplies.

• 4 slopes (15, 25, 70 200 s).

• The kick at 340/MeV/c/charge is 10 mrad max

Bumpers.pcxBumpers.pcx

Page 25: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Les résultats

• 4‰ (-1 to 3) injected.• Up to 6 109 charges per

injection with machine 97 and 200s bump fall.

• With injection all day long, degradation of vacuum.

Spectre.pcxSpectre.pcx

Page 26: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Conséquences sur le vide• Losses due to multiturn

injection, charge exchange with résidual gases and électron recombination give outgassing of vacuum chamber and specially BIPM( Vespel®, Kapton®).

• Limit accumulation (next chapter) and gives life time of less than 1 s.

• BIPMV out gives 5 s. during accumulation with Ie=100 mA.

pression partielles des gaz principaux (%)

0

10

20

30

40

50

60

70

80

H2 CH4 C0

Axis

Titl

e

avant injection

injection permanente

Page 27: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

LA MULTI-INJECTION

• Le principe

• les résultats

Page 28: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Le Principe• Inject a beam and cool it

to -x‰ in momentum in less than the répétition cycle.

• -x‰ is such that the stack is not lossed during next injection

• The cooling could be done using beam dragging for machine with zéro-dispersion at the cooler -3

-2

-1

0

1

2

3

4

5

-30 -20 -10 0 10 20 30

x[mm]

dp/p

dp/pecool

dp/pmach

xeps-

xeps+

dp/pecool

Page 29: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Les résultats• Up to 1.7 1010 charges

accumulated (saturation effect due to vacuum degradation and other beam losses) using machine 97 and Ie=100 mA. Cooling time with dragging is less than 400 ms.

Nombre de charges injectées et durée de vie en fonction du nombre de shots]

0

2

4

6

8

10

12

14

0 20 40 60 80 100 120

nombre de shot injectés

Multishots.xlsMultishots.xls

Page 30: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

Multi-injection seen on transfo

Stacking.pcxStacking.pcx

Page 31: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

MULTI-INJECTION WITH MACHINE 97 (Ie=110mA,ht=10V,300ms,R=50 ms)

• Top view of long. Schottky • Top view horizontal Schottky

pbc027pbc027

Ti m

e [10

00m

s t o

t.]

Ti m

e [10

00m

s t o

t.]dp/p[4%o tot]

Page 32: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

MULTI-INJECTION WITH MACHINE 97 (Ie=110mA,ht=10V,300ms,R=50 ms) BIPMH

BIPM Beam Size During Stacking

0

2

4

6

8

10

12

0 1000 2000 3000 4000 5000 6000

time [s]

sig

ma [

mm

]

without sweeping

with sweeping

Tcool1.xlsTcool1.xls

Page 33: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

MULTI-INJECTION WITH MACHINE 1

• The first tests show that no dragging is (needed) possible.

• Cooling with Ie=100mA is about 400 ms.

Page 34: LEAD ION TESTS IN LEAR PPC - 19 Septembre 1997 M. CHANEL

CONCLUSIONS

• Ecool 2 times longer give ~2 times more cooling rate

• Machine 97 good for combined multi-turn injection

• beam stacking up to 1.7 1010 charges is working well

• machine 1 not completely tested

• stacking at 3 Hz rate not tested

• Good vacuum quality very important

• Still to do