new fast wire scanners in 4l1 and 11l1 - vacuum outgassing measurements and vacuum pressure...
TRANSCRIPT
Friederike Salveter 1
New Fast Wire Scanners in 4L1 and 11L1- Vacuum outgassing measurements and vacuum
pressure simulations –(Friederike Salveter, Jose Antonio Ferreira Somoza, Paul Demarest, Alice Ingrid Michet, Jan Hansen)
2
Layout of the PSB ring
2
Simulation 4L1
Simulation 11L1
Position of the new Wirescanners
3
• Outgassing tests on wire scanner components were conducted in 2013 and 2014 The highest value of the
sum of the measured outgassing
Q10h= 1.34∙10-5 mbar∙l∙s-1
•An outgassing test of an assembled SPS wire scanner was done in 2014:
Outgassing of this Wire scanner:
Q10h= 8.1∙10-5 mbar∙l∙s-1
Pumpdown:
P∝1/t0.5
No contamination observed
=>The tested components don’t explain the outgassing observed
=> Proposal: test all the possible sources (non-metal) before building the next wire scanners
SPS Fast Wire Scanner - Outgassing measurements in 2014
Curtesy of Jose Antonio Ferreira Somoza
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Tests of the new Fast Wire Scanners components
Component Outgassing, 10h (mbar l s-1)
Pollution
The arm
8.4x10-7 Sulfur
The optical fibre
6.8x10-6 Presence of air
The nut
2.6x10-6 Presence of oil
The ferritesEstimated to 2.0x10-7 None
•The optical fiber has the highest gas load 2 types of optical fibers available
(tested in November 2013) It is recommended to use the
one with the lower outgassing rate
•The sulfur detected in the arm is not acceptable in a vacuum system
•Not all the components that will be installed in the wire scanners have been received for the measurements
Curtesy of Alice Ingrid Michet
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Ion Pump270 l s-1
Pressure simulation - Current pumping
Beam
Ion Pump270 l s-1
Ion Pump400 l s-1
Beam
Ion Pump400 l s-1
2.5x10-8 1x10-7
1x10-8 3.5x10-8
Pressure Gradient (mbar)
Pressure Gradient (mbar) BR.BHZ 32
Multipole4L1 type A
Corrector4L1 type 1
BR.BHZ 41
BR.BHZ 102
Corrector
11L1 ty
pe 1
Multipole
11L1 ty
pe IIB
BR.BHZ
121
11L1
4L1
Parameter used in the simulation Value Unit
Time 4 Weeks
Outgassing Stainless Steel 2x10-11 mbar l s-1 cm-2
Total outgassing of 1 Wire scanner 1x10-5 mbar l s-1
Current Pumping SpeedIon pump 1 & 2 400 l s-1
Current Pumping SpeedIon pump 3 270 l s-1
Pumping speed Titanium Sublimation Pump (TSP) 1000 l s-1
Simulated Gas N2 -
TSP
TSP
TSP
TSPTSP
TSP
11L2
11L1
10L5
4L2
4L1
3L5
10000 8000 6000 4000 2000 01E-9
2E-9
3E-9
4E-9
5E-9
6E-9
7E-9
p (
mb
ar)
Length (mm)
20_400/400/270 -1- 20_400/400/270 -2- 20_400/400/270 -3- 20_400/400/270 -4- 21_400/400/270_TSP -1- 21_400/400/270_TSP -2- 21_400/400/270_TSP -3- 21_400/400/270_TSP -4-
8000 6000 4000 2000 01E-9
2E-9
3E-9
4E-9
5E-9
6E-9
p (
mb
ar)
Length (mm)
9_400/400/270 -1- 9_400/400/270 -2- 9_400/400/270 -3- 9_400/400/270 -4- 10_400/400/270_TSP -1- 10_400/400/270_TSP -2- 10_400/400/270_TSP -3- 10_400/400/270_TSP -4-
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Pressure simulation - Current pumping
11L1
4L1
Solid graphs:• No wire scanners• TSPs not sublimated
Dashed graphs:• No Wire scanners• TSPs sublimated
Beam
Beam
BR.BHZ 32
Multipole 4L1Corrector 4L1
BR.BHZ 41
BR.BHZ 102Corrector 11L1
Multipole 11L1
BR.BHZ 121
Manifold 11L2
Manifold 11L1
Manifold 10L5
Manifold 4L2Manifold 4L1
Manifold 3L5
! Due to the amount of simulations only the green slopes will be shown as reference in the following graphs
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Pressure simulation - with Wire Scanners
Beam
Beam
BR.BHZ 32
Multipole4L1 type A
Corrector4L1 type 1
BR.BHZ 41
BR.BHZ 102
Corrector
11L1 ty
pe 1
Multipole
11L1 ty
pe IIB
BR.BHZ
121
11L1
4L1
11L2
11L1
10L5
4L2
4L1
3L5Outgassing per W
ire sc
anner:
1. 10-5 mbar l
s-1
8
9000 8000 7000 6000 5000 4000 3000 2000 1000 01E-9
1E-8
1E-7
p (
mb
ar)
Length (mm)
2_WS320_400/400/270 -1- 2_WS320_400/400/270 -2- 2_WS320_400/400/270 -3- 2_WS320_400/400/270 -4- 6_WS320_400/400/270_TSP -1- 6_WS320_400/400/270_TSP -2- 6_WS320_400/400/270_TSP -3- 6_WS320_400/400/270_TSP -4- 1_WS000_400/400/270 -1- 4_WS000_400/400/270_TSP -1- 9_400/400/270 -1- 10_400/400/270_TSP -1-
10000 9000 8000 7000 6000 5000 4000 3000 2000 1000 01E-9
1E-8
1E-7
p (
mb
ar)
Length (mm)
20_400/400/270 -1- 21_400/400/270_TSP -1- 22_WS000_400/400/270 -1- 23_WS000_400/400/270_TSP -1- 24_WS320_400/400/270 -1- 24_WS320_400/400/270 -2- 24_WS320_400/400/270 -3- 24_WS320_400/400/270 -4- 25_WS320_400/400/270_TSP -1- 25_WS320_400/400/270_TSP -2-
Pressure simulation - with Wire Scanners
11L1
4L1
Solid graphs:• Wire scanners in place• TSP not sublimated
Dashed graphs:• Wire scanners in place• TSP sublimated
Beam
Beam
BR.BHZ 32BR.BHZ 41
BR.BHZ 102BR.BHZ 121
Wire scanners
Wire scanners
Manifold 11L1
Manifold 4L1
BASELINE without Wire scanners:TSP not sublimated TSP sublimated
BASELINE without Wire scanners:TSP not sublimated TSP sublimated
With Wire scanners:TSP not sublimated + WSTSP sublimated + WS
With Wire scanners:TSP not sublimated + WSTSP sublimated + WS
+ ca. 1.2 decades!
+ ca. 1.2 decades!
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Pressure simulation - additional pumping
Beam
Beam
BR.BHZ 32
Multipole4L1 type A
Corrector4L1 type 1
BR.BHZ 41
BR.BHZ 102
Corrector
11L1 ty
pe 1
Multipole
11L1 ty
pe IIB
BR.BHZ
121
11L1
4L1
11L2
11L1
10L5
4L2
4L1
3L5Outgassing per W
ire sc
anner:
1. 10-5 mbar l
s-1
Þ Additional pumps installed on the wire scanner: 1 NEG pump (SAES Nextorr® D-1000-10) at each
wire scanner (320 l s-1 for N2)
4x320 l s-1
4x320 l s-1
10
9000 8000 7000 6000 5000 4000 3000 2000 1000 01E-9
1E-8
1E-7
p (
mb
ar)
Length (mm)
2_WS320_400/400/270 -1- 2_WS320_400/400/270 -2- 2_WS320_400/400/270 -3- 2_WS320_400/400/270 -4- 6_WS320_400/400/270_TSP -1- 6_WS320_400/400/270_TSP -2- 6_WS320_400/400/270_TSP -3- 6_WS320_400/400/270_TSP -4- 1_WS000_400/400/270 -1- 4_WS000_400/400/270_TSP -1- 9_400/400/270 -1- 10_400/400/270_TSP -1-
10000 9000 8000 7000 6000 5000 4000 3000 2000 1000 01E-9
1E-8
1E-7
p (
mb
ar)
Length (mm)
20_400/400/270 -1- 21_400/400/270_TSP -1- 22_WS000_400/400/270 -1- 23_WS000_400/400/270_TSP -1- 24_WS320_400/400/270 -1- 24_WS320_400/400/270 -2- 24_WS320_400/400/270 -3- 24_WS320_400/400/270 -4- 25_WS320_400/400/270_TSP -1- 25_WS320_400/400/270_TSP -2-
Pressure simulation - Wire Scanners & additional pumping
11L1
Beam
Beam
BR.BHZ 41
BR.BHZ 102BR.BHZ 121
Manifold 11L1
Manifold 4L1
BR.BHZ 32
With Wire scanners:TSP not sublimated + WSTSP sublimated + WS
With Wire scanners:TSP not sublimated + WSTSP sublimated + WS
4L1
Solid graphs:• Wire scanners in place• Add. pumping of 320 l s-1 per Wire scanner• TSP not sublimated
Dashed graphs:• Wire scanners in place• Add. pumping of 320 l s-1 per Wire scanner• TSP sublimated
BASELINE without Wire scanners:TSP not sublimated TSP sublimated
BASELINE without Wire scanners:TSP not sublimated TSP sublimated
+ ca. 1.2 decades!
+ ca. 1.2 decades!
< 1 decade
< 1 decade
Wire scanners
Wire scanners
11
Summary (pressure after 4 weeks)
Wire scanner Add. Pumping(Wire scanner)
Add. Pumping (Manifold)
Pressure 4L1 (Wire scanner)
Pressure 11L1(Wire scanner)
No NoNo 4.5x10-9 mbar 4.4x10-9 mbar
Sublimation 2.2x10-9 mbar 2.1x10-9 mbar
Yes NoNo 8.0x10-8 mbar 7.9x10-8 mbar
Sublimation 5.2x10-8 mbar 4.7x10-8 mbar
Yes 4x320 l s-1No 2.9x10-8 mbar 3.1x10-8 mbar
Sublimation 2.7x10-8 mbar 2.6x10-8 mbar
> 1 decade!
Conclusion:• With the current high outgassing additional pumping at the wire scanners
is required to meet the vacuum specifications Extra costs (pumps, cabling, controls) Proposal: Use a manifold for 4 Wire Scanners
=> One big pump could be used instead of four small ones• The outgassing of the different components should be reduced whenever
possible
< 1 decade