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

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

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

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)

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

LE REFROIDISSEMENTEN INJECTION MONOTOUR

• La charge d’espace

• Le cooling des grandes émittances

• les comparaisons des différentes machines

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+

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+

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+

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+

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.

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

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

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

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]

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]

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]

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

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

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

L’INJECTION MULTITOURS COMBINÉE

• Le Principe

• Le LinacIII

• Les bumpers

• Le résultat sur la machine 97

• Conséquences sur le vide

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

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

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

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

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

LA MULTI-INJECTION

• Le principe

• les résultats

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

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

Multi-injection seen on transfo

Stacking.pcxStacking.pcx

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]

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

MULTI-INJECTION WITH MACHINE 1

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

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

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