MuCool RF Status MICE C ollaboration Meeting June 7-10, 2006, Fermilab
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MuCool RF Status MICE C ollaboration Meeting June 7-10, 2006, Fermilab A. Moretti June 9 , 2006
description
MuCool RF Status MICE C ollaboration Meeting June 7-10, 2006, Fermilab. A. Moretti June 9 , 2006. Talk Outline. Purpose and Description of the Experimental 201 MHz and 805 MHz Setups Conditioning Radiation measurements over time with some Old Lab G measurements - PowerPoint PPT Presentation
Transcript of MuCool RF Status MICE C ollaboration Meeting June 7-10, 2006, Fermilab
MuCool RF StatusMICE Collaboration Meeting
June 7-10, 2006, Fermilab
A. Moretti
June 9 , 2006
A. Moretti, Mice Collaboration Meetin, 06/09/06 2Fermilab
Talk Outline
• Purpose and Description of the Experimental 201 MHz and 805 MHz Setups
• Conditioning Radiation measurements over time with some Old Lab G measurements
• Effect of 2.5 T Magnetic Field on Breakdown limit and radiation.
• Current Status 06/09/2006• Conclusions and future plans
A. Moretti, Mice Collaboration Meetin, 06/09/06 3Fermilab
Purpose for Test Setups in the MTA
• Study Breakdown Limit of Vacuum Cavities.• Study Dark Current and X-Ray emissions at
high gradient.• Study the effect of High Magnetic on Breakdown,
Dark Current and X-Ray emissions.• Study Fast Muon Detectors in this environment.• Study methods to reduce dark current with
different materials, Coatings and processing.• Also used by Muoninc to study same in High
Pressure Gas (H2) Cavities.
A. Moretti, Mice Collaboration Meetin, 06/09/06 4Fermilab
Description of the Experimental Setups
• Same as in Lab G and the Fermilab Linacs:• Linac Modulator and Controls.• 12 MW, 805 MHz Klystron and WR975 Waveguide; and
5 MW, 201 MHz Amplifier and 0.23 m Coax Line.• Cavity High Vacuum System. • Cavity Water System.• 5.0 T Solenoid.• Support Cryogenic System.• X-Ray Shielded Cave and X-Ray monitors.
Surrounding the cavity.• Interlocked RF with Sparking, Cavity Vacuum• and External X-Ray level.
A. Moretti, Mice Collaboration Meetin, 06/09/06 5Fermilab
MTA Experimental Layout
Rad Detector # 1
Detector # 2
805 MHz Cavity 201 MHz
Cavity
5 T Solenoid
1.34 m 1.16 m
Window
0.2 m
Detector
# 3
8 scintillation counter are being installed to measure angular Radiation Distribution.
A. Moretti, Mice Collaboration Meetin, 06/09/06 6Fermilab
View of MTA Experimental Layout
201 MHz Drive Line:
.23 Dia Coax Split in middle to Drive the Two cavity coupling Ports. Coax is necked down in size to 0.15 Dia and finally 0.10 Coax for the Couplers; length 120 m
805 MHz Drive Line:
WR975 Waveguide; length 120 m
A. Moretti, Mice Collaboration Meetin, 06/09/06 7Fermilab
201 MHz Photo-multiplier Arc Detector
•Operates at 24 V with internal HV multiplier,
•0.038 m Dia and 0.088 m Length
A. Moretti, Mice Collaboration Meetin, 06/09/06 8Fermilab
201 MHz Triode Cavity Amplifier 5 MW
• RF Power- 5 MW
• Pulse- 500us, 15 Hz
• Grounded Grid
• Cathode driven
• Freq- 201.25 MHz
• Gain- 28 dB.
• 25-30 KV, 300 A
Modulator
Cavity Amplifier
A. Moretti, Mice Collaboration Meetin, 06/09/06 9Fermilab
Control Racks and Modulator for the 201 MHz Amplifier
Linac Gallery:
Control Racks
Modulator
A. Moretti, Mice Collaboration Meetin, 06/09/06 10Fermilab
805 MHz Amplifier in the Linac Gallery
805 MHz in Linac Gallery:
12 MW klystron
Pulse Forming Network
Power Supply
A. Moretti, Mice Collaboration Meetin, 06/09/06 11Fermilab
First MTA 805 MHz Cavity under Test
• First test with Curved Be Windows coated with TiN.
• Flat windows were Freq unstable because EM impulse.
• Frequency instability stopped by Eddy current brake in Magnetic Field.
• Curved window have been shown to be frequency stable without magnetic field.
A. Moretti, Mice Collaboration Meetin, 06/09/06 12Fermilab
First RF 805 MHz Commissioning in the MTA without Magnetic Field
Radation Mon.#1 vs Gradient
0
100
200
300
400
500
600
700
800
900
1000
10 15 20 25 30 35
Gradient in MV/m
Ra
dia
tio
n in
mR
em
/hr
+ Time
A. Moretti, Mice Collaboration Meetin, 06/09/06 13Fermilab
805 MHz MTA 10Log(Radiation) versus Gradient
-12
-2
8
18
28
38
48
58
10 15 20 25 30 35
Gradient in MV/m
An
tiL
og
Rad
iati
on
in
mR
em
/hr
Time IncreasingOver a 30 day span
First RF 805 MHz Commissioning in the MTA without Magnetic Field
View of same on 10Log scale
A. Moretti, Mice Collaboration Meetin, 06/09/06 14Fermilab
First 805 MHz Radiation Measurement in the MTA with Magnetic Field compared to No Field Data
Rad Mon #1 vs Grad with 2.5 T, justa-positioned with no Field
0
200
400
600
800
1000
1200
0 5 10 15 20 25 30 35
Grad mV/m
Ra
dia
tio
n m
Re
m/h
r
2.5 T Line
Lines Without Magnetic Field
A. Moretti, Mice Collaboration Meetin, 06/09/06 15Fermilab
805 MHz Rad Data Before, During and After Operation with Magnetic field
Rad Data Before, During and After opertion with Magnetic Field
0
200
400
600
800
1000
1200
1400
0 5 10 15 20 25 30 35
Gradient MV/m
Rad
iati
on
mR
em
/m
2.5 T Line
Lines After Field operation
First lines No Field
A. Moretti, Mice Collaboration Meetin, 06/09/06 16Fermilab
Comparison of Lab G Results with the MTA Data
Safe Operating Gradient Limit vs Magnetic Field Level at Window for the three different
Coil modes
40403736
3432.431.73128.8
26.7426.425.922
404037.663535.2
3028.527.327
4040
25.7523.2522.521.520.9
16.5 15 13.5
0
5
10
15
20
25
30
35
40
45
0 1 2 3 4 5Peak Magnectic Field in T at the Window
Ele
ctr
ic G
ra
die
nt
in M
V/m
(Solenoid)Yellow
(Opposing) Red
(Single Coil)Black Diamond
MTA Result
A. Moretti, Mice Collaboration Meetin, 06/09/06 17Fermilab
201 MHz Radiation vs. RF Commissioning Time
201 MHz Cavity X-ray level 0.33 m in Front Cu Window
0
50
100
150
200
250
300
0 5 10 15 20Gradient in MV/m
Rad
iati
on
in m
Rem
/hr
Day 1
Day 2
Day 5 of RF commissioning
A. Moretti, Mice Collaboration Meetin, 06/09/06 18Fermilab
Lab G Pill Box Cavity X-Ray levels
Lab G Pill Box Cavity X-Ray Levels with Magnatic Feild level
0
100
200
300
400
500
600
700
800
900
1000
20 30 40
Peak Surface Electric Field in MV/m
Ra
dia
tio
n L
ev
el
in m
Re
m/h
r
2.9 T1.7 T0.8 T
0.65 T
0.22 T
0.43 T0.0 T
A. Moretti, Mice Collaboration Meetin, 06/09/06 19Fermilab
Muons, Inc MTA High Pressure H2 Experimental results
A. Moretti, Mice Collaboration Meetin, 06/09/06 20Fermilab
Conclusions and future plans
• Results of Lab G have been verified in the first running at 805 MHz in the MTA.
• We need to continue the study to determine the mechanism for the enhancement of Dark Current in Large Magnetic fields: does it increase number of emitters, the electric enhancement factor, or both?
• The button cavity will be used to study these and other questions: materials, coatings, etc.
• Scintillations counters to Study Angular Distribution of Emissions.
A. Moretti, Mice Collaboration Meetin, 06/09/06 21Fermilab
Button Cavity to continue the 805 MHz Study with different Materials and Coatings.
Removable Button Insert to study different materials, treatments processes and coatings for their effects on breakdown and eissions.
A. Moretti, Mice Collaboration Meetin, 06/09/06 22Fermilab
Current Status
After the long 3 Month Accelerator Shut Down.
•201 MHz Amplifier Refurbishing is nearly completed.
•Magnet Cryogenics Problems have been studied and solutions implemented.
•The 805 MHz and 201 MHz Experimental Program is scheduled to resume on or about 06/15/06.
•805 MHz and 201 MHz Study of Radiation Angular Distribution is ready; Paddle scintillation and Electronics is nearly completed.
•Plans are underway to move the 201 MHz cavity closer to the Magnet so as to be in the Fringe Field of about 1.25 T.
•Plan to install Proton Beam is underway and funded (1 Year)
