MUTAC Review 3/16/06A. Bross
MuCool Overview and Plans
Muon Cooling R&DMUTAC ReviewMarch 16, 2006
A. Bross
MUTAC Review 3/16/06A. Bross
MuCool
Currently consists of 9 institutions from the US and Japan
RF DevelopmentANLFermilabIITJLABLBNLMississippi
Absorber R&DFermilabIITKEKNIUMississippiOsaka
SolenoidsLBNLMississippi
Mission Design, prototype and test all cooling channel components
(SFOFO) 201 MHz RF Cavities, absorbers, SC solenoids
Support MICE (cooling demonstration experiment) Perform high beam-power engineering test of cooling
section components
MUTAC Review 3/16/06A. Bross
MuCool
R&D Focus of MuCool Component testing Fermilab
RF Cavities– High RF-power Testing
Absorbers– Technology tests– High power-load testing
•With beam Magnets
MUTAC Review 3/16/06A. Bross
MuCool Test Area
Facility to test all components of cooling channel (not a test of ionization cooling)
At high beam power Designed to accommodate full Linac Beam 1.6 X 1013
p/pulse @15 Hz – 2.4 X 1014 p/s
– 600 W into 35 cm LH2 absorber @ 400 MeV
RF power from Linac (201 and 805 MHz test stands)
Waveguides pipe power to MTA
MUTAC Review 3/16/06A. Bross
MTA
The MTA is the focus of our Activities
RF testing (805 and 201 MHz)
High pressure H2 gas-filled RF
LH2 Absorber tests
Two parts of infrastructure yet to be completed
Cryo Plant Beam Line
MUTAC Review 3/16/06A. Bross
Towards Experimental Hall
Refrigerator RoomRefrigerator Room
• Tevatron satellite refrigerator to be operated on 5 K mode and 14 K mode (3” DE, 3” WE)
• Helium and nitrogen Dewar
Compressor RoomCompressor Room
• Two 400 HP 2-stage oil injected screw compressors
Heat exchanger
MTA Cryo-Infrastructure
Compressor Installation and piping are complete
Needed forMagnet Operations
andLH2 Absorber Tests
MUTAC Review 3/16/06A. Bross
MTA Cryo Infrastructure
Our goal was to have Cryo Plant Operational by NOW Needed signficant support from AD and PPD Cryo Groups
AD – Wet engine installation/Controls/Commissioning PPD – Transfer line system
But there was a problem Due to resource allocation to ILC cryo work, completing
the MTA Cryo by end of March did not happen Negotiations with the Lab are in progess
Start installation effort again in earnest after shutdown cryo work is completed
New goal is to be operational late Fall Running off 500L LHe dewars will cost the collaboration
approximately $3-4k/week of magnet operation Expensive! – Working to optimize system for most efficient use
of LHe
MUTAC Review 3/16/06A. Bross
MTA High Intensity Beam
MTA
400 MeV beamline for the MTA has been designed
Under Craig Moore/Carol Johnstone
External Beams Department Developed Engineering Design
Cost Schedule
Safety Analysis Linac Area and Beamline Shielding Assessment for MTA
The current beam line design allows for Linac diagnostic
High-Quality emittance measurement
Our goal is to bring Low Intensity to the MTA as soon as possible
MUTAC Review 3/16/06A. Bross
Proceeding with the MTA Beam Line
Cost Estimate: $388k (including 30% contingency) Low-Intensity initial phase
Resources: $100k from Muon Collaboration Requests
PPD Pulsed Extraction Magnets: $75k in FY06 M&S Magnet stand fab
AD – SWF for installation Internal AD review November 30th. The response from the committee
was positive, but they asked a number of questions. A response to these questions has been prepared has submitted.
Review Committee’s final report:– It was agreed that the basic design philosophy is sound, and that the
diagnostic section will be of great use not only to the MTA, but to the general Linac operation as well. Assuming that the items in the above list are addressed, and that doing so identifies no new issues, then the committee can fully support the MTA beam line design.
Modifications in Linac area have just been completed Isolates future MTA beam line work from Linac operations
MUTAC Review 3/16/06A. Bross
MTA – Near Term Test Program
805 MHz high-power testing begins 1/1/06 TiN coated curved Be windows tests Various B field configurations
201 MHz cavity testing begun 3/06 Major Milestone has been reached
LH2 Absorber test Summer 06 Second phase of testing with KEK convective absorber This is dependent on new safety review
MUTAC Review 3/16/06A. Bross
Phase I of RF Cavity Closed Cell Magnetic Field Studies (805 MHz)
Data seem to follow universal curve
Max stable gradient degrades quickly with B field
Sparking limits max gradient
Copper surfaces the problem
Gra
die
nt
in M
V/m
Peak Magnetic Field in T at the Window
MUTAC Review 3/16/06A. Bross
Phase II of 805 MHz studies
Study breakdown and dark current characteristics as function of gradient and applied B field in Pillbox cavity
Curved Be window Test TiN coated Cavity has been
conditioned to 32MV/m without B field
Measurements at 2.5T– So Far – stable
gradient limited to about 14MV/m
Button test Evaluate various
materials and coatings Quick Change over
MUTAC Review 3/16/06A. Bross
RF R&D – 201 MHz Cavity Design
The 201 MHz Cavity is now operating Recently reached 16MV/m at B=0 (design gradient!)
MUTAC Review 3/16/06A. Bross
High Pressure H2 Filled Cavity WorkMuon’s Inc
High Pressure Test Cell Study breakdown properties
of materials in H2
In B field next
MUTAC Review 3/16/06A. Bross
2D Transverse Cooling
and
Figure of merit: M=LRdE/ds
M2 (4D cooling) for different absorbers
Absorber Design Issues
Absorber Accelerator
Momentum loss is opposite to motion, p, p x , p y , E decrease
Momentum gain is purely longitudinal
Large emittance
Small emittance
H2 is clearly Best -Neglecting Engineering
Issues Windows, Safety
MUTAC Review 3/16/06A. Bross
Absorber Design Issues
Design Criteria High Power Handling
Study II – few 100 W to 1 KW with “upgraded” (4MW) proton driver
10 KW in ring cooler– Must remove heat
Safety issues regarding use of LH2 (or gaseous H2)
Window design paramount– H2 containment
Proximity to RF adds constraints (ignition source)
Two Design Approaches Convective Cooling
– Shown to the right Forced flow
– High power handling
H2 implies engineering complexity
MUTAC Review 3/16/06A. Bross
Convective Absorber Activities
First Round of studies of the KEK absorber performed in the MTA
GHe used to input power
MUTAC Review 3/16/06A. Bross
Convective Absorber Activities III
Next Round of tests will use a modified absorber
Test Electrical Heater New
Temperature sensors
LH liquid level sensor
Absorber Body being modified in Lab 6 at Fermilab
Instrumentation will be usedin MICE
MUTAC Review 3/16/06A. Bross
LiH Test Program
Produce encapsulating cast (not pressed) samples Small disk (5-10 cm) for intense radiation
exposure At Fermilab Radiation Test Facility Look at Material stability primarily Temperature Profile
Large disk (30 cm) for detailed thermal conductivity studies
External Cooling + Internal Heating Potential absorber for MICE Phase I
– Non-instrumented, no cooling
This will be far more involvedthan these 3 bullets mightindicate.
MUTAC Review 3/16/06A. Bross
Engineering Concept
SS ring with brazed cooling tubes
Encapsulated with thin SS windows
5-10 micron Instrumentation ports
Hermetic connectors Temp sensors Heater power
Gas pressure port For decomposition
under intense rad studies
Cast LiH with sensors Encapsulate via e-beam
welding of thin windows
MUTAC Review 3/16/06A. Bross
MuCool Plans for the Coming Year
After a long pause due to the loss of our 805 MHz RF test facility in Lab G at Fermilab, we are now up and running again
805 MHz RF studies (with and without B field) Be Window tests Materials tests Surface treatment
201 MHz RF test program off to a Rousing start! B field tests Curved Be Windows
Second round of tests with KEK convective absorber Prototype and test encapsulated LiH absorbers IIT ME thesis student to work on flow-absorber
simulation and test Complete MTA cryo infrastructure installation and
commission system Continue installation of 400 MeV beam line from Linac to
the extent that resources allow
RFHighest Priority!