View
44
Download
0
Category
Preview:
DESCRIPTION
SPS Kicker-Magnet Outgassing with Different Bunch Spacing's. M.J. Barnes, E. Mahner & V. Senaj Acknowledgements: V. Baglin, E. Benedetto, F. Caspers, E. Chapochnikova, K. Cornelis, L. Ducimetière, G. Papotti, G. Rumolo. II. Overview of Presentation. - PowerPoint PPT Presentation
Citation preview
1 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
SPS Kicker-Magnet SPS Kicker-Magnet Outgassing with Different Outgassing with Different
Bunch Spacing'sBunch Spacing's
M.J. Barnes, E. Mahner & V. Senaj
Acknowledgements:V. Baglin, E. Benedetto, F. Caspers, E. Chapochnikova,
K. Cornelis, L. Ducimetière, G. Papotti, G. Rumolo
2 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
II. Overview of PresentationOverview of Presentation
• Brief description of a kicker magnet; • During MD of August 12th to 14th, 2008 interlocks (trips) due to pressure rise, with 50ns beam, at MKDV1 and ion traps.
• Summary, for SPS kicker magnets, of temperature and pressure;
• Significant temperature rise of some kicker magnets noted, at some bunch spacing's; this is thought to be understood and independent of out-gassing;• Out-gassing summary for a bunch spacing of 25ns, 50ns or 75ns.
• During MD of October 6th to 8th, 2008 pressure rise-noted at MKDV1, but no trips (however, interlocks due to ion traps).
• Summary of out-gassing for SPS kicker magnet, from MD, of high resolution vacuum measurements.
• Overall summary.
3 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
PS
LHC
SPS
PS ComplexPS
LHC
SPS
PS Complex
30 x MKD
12 x MKBV
8 x MKBH
MKQH
2 x MKDV
3 x MKDH
MKQV
5 x MKE
4 x MKQAV
4 x KKQAH
4 x MKQAV
4 x KKQAH
4 x MKI4 x MKI
30 x MKD
12 x MKBV
8 x MKBH
4 x MKI
4 x MKE5 x MKE4
MKQH
2 x MKDV
3 x MKDH
MKQV
3 x MKE6
4 x MKP
PS
LHC
SPS
PS ComplexPS
LHC
SPS
PS ComplexPS
LHC
SPS
PS ComplexPS
LHC
SPS
PS Complex
30 x MKD
12 x MKBV
8 x MKBH
MKQH
2 x MKDV
3 x MKDH
MKQV
5 x MKE
4 x MKQAV
4 x KKQAH
4 x MKQAV
4 x KKQAH
4 x MKQAV
4 x KKQAH
4 x MKQAV
4 x KKQAH
4 x MKI4 x MKI4 x MKI4 x MKI
30 x MKD
12 x MKBV
8 x MKBH
4 x MKI
4 x MKE5 x MKE4
MKQH
2 x MKDV
3 x MKDH
MKQV
3 x MKE6
4 x MKP
SPS & SPS & LHCLHC KICKER SYSTEMS KICKER SYSTEMS
4 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT1 cell
Simplified view of a transmission Simplified view of a transmission line kicker magnet line kicker magnet
Transition pieces, between magnet tank and magnet frame, installed in some kicker magnets.
MKE magnet:
FERRITE
Return Conductor
Go Conductor
Vap
Hap
Cross-Section of MKDV1 (Vertical) ApertureMKDV1:
Pumps
Pressure Gauge
Pipe: ~16cm ID & ~49cm long
5 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
SUMMARY OF SPS KICKER SUMMARY OF SPS KICKER APERTURES & MATERIALSAPERTURES & MATERIALS
SPS
KICKER
COMMENTS Hap (mm) Vap (mm) MAGNETIC MATERIAL
Max. Pressure [MD Aug 2008] (1s
resolution)
MKP-SMKP-L
Beryllium for return cond.
101141
6154
8C11 Ferrite8C11 Ferrite
Not significantly: ~2e-8mbar
MKQH Inserts with Silver paint
135 33.9 8C11 Ferrite 75ns beam: ~3e-7mbar
MKQV 56 102 8C11 Ferrite 50ns beam: ~2e-7mbar
MKDV1A
MKDV25656
7583
8C11 Ferrite8C11 Ferrite
50ns beam: ~1e-6mbar50ns beam: ~7e-7mbar
MKDH1/2MKDH3
Glass fibre 96105
5660
Laminated Si SteelLaminated Si Steel
50ns beam: ~1e-7mbar50ns beam: ~5e-8mbar
MKE-SMKE-L
Silver/Glass stripes for L10
135147.7
3235
8C11 Ferrite8C11 FerriteB
MKE6 (50ns):~4e-7mbarMKE4 No: : ~3e-8mbar
Aluminium (Anticorodal 110) generally used for conductors.A Remnant field estimated to be <1 G for 8C11 and ~5G for 4E2;B Except “L9” @ MKE6 4E2 ferrite (higher degassing rate than 8C11) FERRITE
Vap
Hap
6 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
MKDV Temperature & Pressure on 12, MKDV Temperature & Pressure on 12, 13 & 1413 & 14thth August 2008 August 2008
0.0E+00
5.0E-08
1.0E-07
1.5E-07
2.0E-07
2.5E-07
3.0E-07
3.5E-07
4.0E-07
4.5E-07
5.0E-07
12-08-08 0:00
12-08-08 6:00
12-08-08 12:00
12-08-08 18:00
13-08-08 0:00
13-08-08 6:00
13-08-08 12:00
13-08-08 18:00
14-08-08 0:00
14-08-08 6:00
14-08-08 12:00
14-08-08 18:00
15-08-08 0:00
Date & Time
Pre
ss
ure
(m
ba
r)
26
28
30
32
34
36
38
40
42
44
46
Te
mp
era
ture
(C
)
MKDV1: pressureMKDV2: pressureMKDV1: TemperatureMKDV2: Temperature
25ns beam
3 batches 50ns beam @ 01:43:immediate trip
50ns beam 05:13 to 07:00
75ns beam to 01:30
Normally: MKDV1 temperature>MKDV2 and pressure < 6e-8 mbar (as per 25ns beam);
For 75ns beam MKDV2 temperature > MKDV1 and pressure < 6e-8 mbar;
For 50ns beam MKDV temperature is not an issue, but pressure is an issue!.
8s resolution for pressure.
See next 2 slides.
8s resolution:
Note: Ecloud monitors show maximum Ecloud with 25ns bunch spacing.
7 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
MKDV Pressure on 14/08/2008, MKDV Pressure on 14/08/2008, between 01:20hrs & 02:10hrs.between 01:20hrs & 02:10hrs.
0.00E+00
1.00E-07
2.00E-07
3.00E-07
4.00E-07
5.00E-07
6.00E-07
7.00E-07
8.00E-07
9.00E-07
1.00E-06
14-08-08 1:20
14-08-08 1:25
14-08-08 1:30
14-08-08 1:35
14-08-08 1:40
14-08-08 1:45
14-08-08 1:50
14-08-08 1:55
14-08-08 2:00
14-08-08 2:05
14-08-08 2:10
Date & Time
Pre
ss
ure
(m
ba
r)
26
28
30
32
34
36
38
40
42
44
46
Te
mp
era
ture
(C
)MKDV1: pressureMKDV2: pressureMKDV1: TemperatureMKDV2: Temperature
75ns beam to ~01:30
Started 1 batch 50ns beam at 1:32hrs,
continuously.
Single shot of 4 batches of 50ns beam at 2:05hrs: interlock.
One shot of 2 batches of 50ns beam at
1:42hrs.
One shot of 3 batches of 50ns beam at
1:43hrs: interlock.
Information from: Giulia Papotti:
Summary: 50ns beam causes pressure rise; high pressure with 3 or 4 batches per shot.
1s resolution
8 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
MKDV Pressure on 14/08/2008, MKDV Pressure on 14/08/2008, between 05:00hrs & 07:00hrs.between 05:00hrs & 07:00hrs.
0.0E+00
1.0E-07
2.0E-07
3.0E-07
4.0E-07
5.0E-07
6.0E-07
7.0E-07
8.0E-07
9.0E-07
14-08-08 5:00
14-08-08 5:10
14-08-08 5:20
14-08-08 5:30
14-08-08 5:40
14-08-08 5:50
14-08-08 6:00
14-08-08 6:10
14-08-08 6:20
14-08-08 6:30
14-08-08 6:40
14-08-08 6:50
14-08-08 7:00
Date & Time
Pre
ssu
re (
mb
ar)
26
27
28
29
30
31
32
33
34
35
Te
mp
era
ture
(C
)
MKDV1: pressureMKDV2: pressureMKDV1: TemperatureMKDV2: Temperature
Started 1 batch 50ns beam at 5:13hrs.
One shot of 3 batches of 50ns beam at
5:39hrs.
Four shots of 4 batches of 50ns beam at 5:41hrs: interlock.
Four shots of 4 batches of 50ns beam
at 5:45hrs.
Two shots of 4 batches of 50ns beam
at 5:49hrs.
Information from: Giulia Papotti:
One batch per shot of 50ns beam from
6:05hrs to 7:00hrs.
Summary: 50ns beam causes pressure rise; high pressure with 3 or 4 batches per shot.
1s resolution
9 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
SPS Kickers: Vacuum, August SPS Kickers: Vacuum, August 14, 200814, 2008
August 14, 2008
0.0E+00
1.0E-07
2.0E-07
3.0E-07
4.0E-07
5.0E-07
6.0E-07
7.0E-07
8.0E-07
9.0E-07
1.0E-06
0:000:30
1:001:30
2:002:30
3:003:30
4:004:30
5:005:30
6:006:30
7:00
Time
Pre
ss
ure
(m
ba
r)
MKDV1
MKDV2
MKE6: August 14, 2008
0.0E+00
5.0E-08
1.0E-07
1.5E-07
2.0E-07
2.5E-07
3.0E-07
3.5E-07
4.0E-07
0:000:30
1:001:30
2:002:30
3:003:30
4:004:30
5:005:30
6:006:30
7:00
Time
Pre
ss
ure
(m
ba
r)
MKE1 (serigraphed)
MKE2 (No cells serigraphed)
MKE3 (2 cells serigraphed)
75ns beam
3 batches, 50ns 4 batches, 50ns
4x4 batches, 50ns
50ns beam
August 14, 2008
0.0E+00
1.0E-08
2.0E-08
3.0E-08
4.0E-08
5.0E-08
6.0E-08
7.0E-08
8.0E-08
9.0E-08
1.0E-07
0:301:00
1:302:00
2:303:00
3:304:00
4:305:00
5:306:00
6:307:00
Time
Pre
ss
ure
(m
ba
r)
MKDH1
MKDH2
MKDH3
75ns beam
75ns beam
3 batches, 50ns 4 batches, 50ns
4 batches, 50ns3 batches, 50ns
4x4 batches, 50ns
4x4 batches, 50ns
50ns beam
50ns beam
MKDV1: Hap=56mm, Vap=75mmMKDV2: Hap=56mm, Vap=83mm
MKDH1: Hap=96mm, Vap=56mmMKDH2: Hap=96mm, Vap=56mmMKDH3: Hap=105mm, Vap=60mm
MKE1: Hap=147.7mm, Vap=35mmMKE2: Hap=147.7mm, Vap=35mmMKE3: Hap=135mm, Vap=32mm
Transition pieces Ferrite
No transition piecesFerrite
No transition pieces.0.35mm laminated steelNo temperature probes.
1s resolution
- 4E2 ferrite, 1 of 2
pumps inoperative
0.00E+00
1.00E-08
2.00E-08
3.00E-08
4.00E-08
5.00E-08
6.00E-08
7.00E-08
8.00E-08
9.00E-08
Time
Pre
ss
ure
(m
ba
r)
MKE1MKE2MKE3MKE4MKE5
75ns beam
3 batches, 50ns
4 batches, 50ns 4x4 batches, 50ns
50ns beam
MKE1: Hap=147.7mm, Vap=35mmMKE2: Hap=147.7mm, Vap=35mmMKE3: Hap=135mm, Vap=32mmMKE4: Hap=135mm, Vap=32mmMKE5: Hap=147.7mm, Vap=35mm
Transition pieces
MKE4
10 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
SPS Kickers: Vacuum, August SPS Kickers: Vacuum, August 14, 200814, 2008
August 14, 2008
0.0E+00
1.0E-07
2.0E-07
3.0E-07
4.0E-07
5.0E-07
6.0E-07
7.0E-07
8.0E-07
9.0E-07
1.0E-06
0:000:30
1:001:30
2:002:30
3:003:30
4:004:30
5:005:30
6:006:30
7:00
Time
Pre
ss
ure
(m
ba
r)
MKDV1
MKDV2
0.0E+00
2.0E-09
4.0E-09
6.0E-09
8.0E-09
1.0E-08
1.2E-08
1.4E-08
1.6E-08
1.8E-08
2.0E-08
0:000:30
1:001:30
2:002:30
3:003:30
4:004:30
5:005:30
6:006:30
7:00
Time
Pre
ssu
re (
mb
ar)
MKP4
MKP3
MKP2
MKP1
75ns beam
75ns beam
3 batches, 50ns 4 batches, 50ns
4 batches, 50ns
3 batches, 50ns
4x4 batches, 50ns
4x4 batches, 50ns
50ns beam
50ns beam
MKDV1: Hap=56mm, Vap=75mmMKDV2: Hap=56mm, Vap=83mm
12xMKP-S: Hap=101mm, Vap=61mm4xMKP-L: Hap=141mm, Vap=54mm
No transition piecesFerrite
1s resolution
SPS MKQ: 14th August 2008
1.0E-09
5.1E-08
1.0E-07
1.5E-07
2.0E-07
2.5E-07
0:000:30
1:001:30
2:002:30
3:003:30
4:004:30
5:005:30
6:006:30
7:00
Time
Pre
ss
ure
(m
ba
r)
MKQH (ceramic substrate for impedance reduction)
MKQV
75ns beam4 batches, 50ns
3 batches, 50ns
4x4 batches, 50ns
50ns beam
MKQH: Hap=135mm, Vap=33.9mmMKQV: Hap=56mm, Vap=102mm
MKQH less sensitive to 50ns & more sensitive to 75 bunch spacing….No temperature probes.
11 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
MKDV1 Kicker: Vacuum, MKDV1 Kicker: Vacuum, October 6October 6thth to 8th, 2008 to 8th, 2008
30
32
34
36
38
40
42
44
46
48
500
6/1
0 0
0:0
0
06
/10
03
:00
06
/10
06
:00
06
/10
09
:00
06
/10
12
:00
06
/10
15
:00
06
/10
18
:00
06
/10
21
:00
07
/10
00
:00
07
/10
03
:00
07
/10
06
:00
07
/10
09
:00
07
/10
12
:00
07
/10
15
:00
07
/10
18
:00
07
/10
21
:00
08
/10
00
:00
08
/10
03
:00
08
/10
06
:00
08
/10
09
:00
08
/10
12
:00
08
/10
15
:00
08
/10
18
:00
08
/10
21
:00
09
/10
00
:00
Date (2008) & Time
Tem
per
atu
re (
C)
0.0E+00
5.0E-08
1.0E-07
1.5E-07
2.0E-07
2.5E-07
3.0E-07
3.5E-07
4.0E-07
4.5E-07
5.0E-07
Pre
ssu
re (
mb
ar)
MKDV1MKDV2MKDV1
50ns
bea
m
50ns beam, intensity scan
50ns beam
450e
10
ppba
tch
75ns
be
am
23:5
5: n
om.
Inte
nsity
25ns beam
4 ba
tche
s
1 bu
nch
3 ba
tche
s
high intensity
8s resolution
See next side
12 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
• Volume of MKDV1 tank is ~0.3m3;• 3 ion pumps for each magnet, rated at 350 l/s each (1050 l/s total);• ideal τ for decay of pressure of 0.3s;• 3τ is ~ consistent with measurement (16cm ID, 49cm long pipes connecting to pump...).
MKDV1 Kicker: Vacuum, MKDV1 Kicker: Vacuum, October 7October 7thth, 2008: 50ns beam, 2008: 50ns beam
16ms resolution
~4s2s
21.6s supercycle
BCT data courtesy of Elena Benedetto
13 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
MKDV Pressure Peak versus MKDV Pressure Peak versus Bunch Intensity (4 batches)Bunch Intensity (4 batches)
50ns bunch spacing; The instantaneous pressure rises in MKDV kickers
shows a clear threshold effect with intensity.
MKDV1
MKDV2
(mba
r)
Plot courtesy of Karel Cornelis
14 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
SummarySummary 50ns bunch spacing causes immediate pressure rise (surface
effect-e.g. electron cloud) for both MKDV1 & MKDV2 – but MKDV1 is more significant;
Pressure rise shows an intensity threshold (>6x1010 protons/bunch);
Measured pressure rise appears to be real as pressure fall is reasonably consistent with installed pumping rate;
Pressure rise is dependent upon: Beam intensity; Number of batches; Bunch length (K. Cornelis presentation to SPSU 18/11/2008);
MKE6, MKDH, MKDH & MKQV kickers all show immediate pressure rise with 50ns bunch spacing ….. But MKQH sensitive to 75ns bunch spacing;
• But Ecloud monitors show maximum Ecloud with 25ns bunch spacing...
15 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
Questions & CommentsQuestions & Comments
16 ECLOUD Workshop: Nov. 20-21, 2008
Mike Barnes, AB/BT
MKE: Beam Coupling MKE: Beam Coupling Impedance ReductionImpedance Reduction
Beam coupling impedance is reduced using conductive stripes (serigraphy), i.e. interleaved comb structure, directly printed onto the ferrite blocks and a reliable contact to the metallic HV plates at either side;
Capacitive coupling between stripes (stripes carry beam image current).
Printed strips in MKE-L10
Interdigital comb structure 20mm spacing
surface discharge
Recommended