mutac review 3/16/06 a. bross mucool overview and plans muon cooling r&d mutac review march 16,...

MUTAC Review 3/16/06A. Bross

MuCool Overview and Plans

Muon Cooling R&DMUTAC ReviewMarch 16, 2006

A. 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


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


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


MTA Hall Today


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


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


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


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


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


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


RF Cavity R and D

ANL/FNAL/IIT/LBNL/UMiss


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


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


RF R&D – 201 MHz Cavity Design

The 201 MHz Cavity is now operating Recently reached 16MV/m at B=0 (design gradient!)


High Pressure H2 Filled Cavity WorkMuon’s Inc

High Pressure Test Cell Study breakdown properties

of materials in H2

In B field next


Absorber R and D

IIT/KEK/NIU/Osaka/UMiss


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


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


Convective Absorber Activities

First Round of studies of the KEK absorber performed in the MTA

GHe used to input power


Convective Absorber Activities II


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


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.


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


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!

mutac review 3/16/06 a. bross mucool overview and plans muon cooling r&d mutac review march 16,...

Documents

u negotiations

mta slide

u cryo plant u beam

rf u lh

bross slide

mev u rf power

linac beam s

high beam power s