technical challenges of future neutrino beams
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Technical Challenges of future neutrino beams. Mary Anne Cummings Northern Illinois University WIN ’03 Lake Geneva, Wisconsin. The current story. Recent results from SNO and SuperK have convinced most of the HEP community that n ’s oscillate, most likely among 3 known n species - PowerPoint PPT PresentationTRANSCRIPT
Technical Challenges of future neutrino beams
Mary Anne CummingsNorthern Illinois University
WIN ’03Lake Geneva, Wisconsin
The current story..
Recent results from SNO and SuperK have convinced most of the HEP community that ’s oscillate, most likely among 3 known species
There exists now ongoing R & D in accelerator and experimental physics based on beams, and the beams that can be extracted from them.
New machines can be developed in an incremental fashion, with a physics program for each step.
Proton drivers can provide intense conventional beams, and can provide an intense source of low energy ’s (via decay)
These ’s must be cooled – an very active R & D program has sprung from developing this new technology.
As a proton driver is being constructed, work on collecting the ’s and cooling them would be continued.
An intense source of cold muons could be immediately used for E and B dipole moments, muonium-antimuonium oscillations, rare decays…
As cooling and acceleration capability is developed, a storage ring could be the basis of the first neutrino factory.
Source of e’s and v’s and their charged conjugates from + an - beams During factory construction, further R & D on acceleration can create
a Higgs factory and higher energy muon colliders … using relatively compact collider rings
A bit of background
Concept of a muon collider: Tinlot (1960), Tikhonin (1968), Budker (1969), Skrinsky
Neuffer (1979), Palmer (1995) Muon Collider Collaboration
Many advantages over electron collider comes from the mass of a muon:
But, they decay, and luminosity becomes a challenge
Fast cooling technique – ionisation cooling – invented 1981:Skrinsky and Parkhomchuk
Another problem…….neutrino radiation!
Idea for a Neutrino Factory comes from seeking a use for beams produced a muon collider storage rings.. this turns out to be very positive! (S. Geer, 1997 FNAL workshop)
207emm
Neutrino Neutrino Factory!Factory!
Enough neutrinos to be a problem …. must be enough to do physics
- R. Edgecock
Muon Collaboration
• Now referred to as the Neutrino Factory and Muon Collider Collaboration– > 140 scientists– MC is sponsored by three national laboratories (BNL, FNAL, LBNL)
• Active Program:– Targetry– Cooling Simulations– RF Hardware – LH2 absorber Designs– High-field solenoids– Emmitance Exchange– Muon Acceleration– Neutrino Factory design studies I and II
• Experiments:– MUCOOL (FNAL) : Cooling channel component development: MTA completed!– MICE (Rutherford-Appleton) Muon cooling measurement: Approved!
• University Participation:– ICAR (Illinois Consortium for Accelerator Research)– Ph.D. and Masters students involvement– State of Illinois support to promote accelerator R & D
Not THAT ICAR…• xx•
• New Book by David M. Jacobs!• Thinking Clearly About UFO Abductions• Video Interview with David Jacobs
• • xxx•
• Welcome to the ICAR•
• Straight Talk About UFO Abductions• The International Center for Abduction Research (ICAR) is an organization devoted to the dissemination of trustworthy information about UFO abductions. The ICAR will provide accurate information to therapists and lay individuals who are interested in abductions, and help cope with the myriad of problems that arise from the use of hypnosis and other memory collection
procedures. David M. Jacobs is the Director of the ICAR and there is a small Board.• A personal note from David M. Jacobs:
I wrote most of the information on this website based on thirty-four years of UFO research and over twelve years of hypnotic regressions with abductees. I have tried to be as objective and as "agenda free" as possible, sticking close to the evidence that I have gathered over the course nearly 800 hypnotic regressions. However, there is no possibility that I have avoided error. The reader must be skeptical of what I say and what all others say in this difficult arena of abductions, hypnosis, popular culture, and cultural expectations. We are all amateurs doing our best to get to the truth knowing that objective reality may elude us.
Muon Collider R & D
Three stage scenario:Neutrino FactoryHiggs FactoryMuon Collider
5 different Neutrino Factory layouts: BNL
CERNFNAL
J-PARC RAL
For example, at least 2 generations of colliders would fit on FNAL site…
Technical Issues:Technical Issues:
1. Proton driver
2. Target and Capture
3. Decay and Phase Rotation
4. Bunching and Cooling
5. Acceleration
6. Storage Ring
BUT…BUT…
Large PH init. Large PH init. beam beam rapid beam rapid beam coolingcooling
Short lifetime Short lifetime rapid rapid acceleration acceleration
Backgrounds:Backgrounds:
Muon colliders: compact design
Technical Staging and Physics
Muon Collider SchematicMuon Collider Schematic
Study II Study II factory.. factory..
Possible Higgs factory..Possible Higgs factory..
JHF Superbeam
Kobayashi
ProtonBeam
Target FocusingDevices
Decay Pipe
Beam Dump
,K
“Conventional” neutrino beam
TargetHornsDecay Pipe
Far Det.“Off-axis”
Proton Driver
Main requirements:
4 MW beam power, 1 ns bunch length, 50Hz
Two types:Linac (BNL type) RCS (FNAL type)
Range of energies:
2.2 to 50 GeV
BNL, FNAL parameters:
R & D: HIPPI
Target
Proposed rotating tantalum target ring
Many challenges: enormous power density lifetime problems pion capture
Replace target between bunches:
Liquid mercury jet or rotating solid target
Stationary target:
RAL
CERN
Liquid Mercury Tests
Tests with a proton beam at
BNL.
• Proton power 16kW in 100ns Spot size 3.2 x 1.6 mm
• Hg jet - 1cm diameter; 3m/s
0.0ms 0.5ms 1.2ms 1.4ms 2.0ms 3.0ms
Dispersal velocity ~10m/s, delay ~40s
Target Facility
Carbon or liquid mercury jet target
20 Tesla capture solenoid
Issues: 1.power dissipation,
target durability2.pion yield of solid &
liquid target3.performance of
capture solenoid in a high radiation environment
Pion Capture
20T 1.25T
Horn Capture
Protons
Current of 300 kA
To decay channel
Hg target B1/R
B = 0
Phase Rotation & Bunching
Beam after drift & adiabatic buncher – Beam is formed into string of ~ 200MHz bunches
Beam after ~200MHz rf rotation; formed into string of equal-energy bunches;matched to cooling RF acceptance
1B & R
2R & B
Alternative:1. Rotation by induction Linac (E-field
gradient on axis) into longer pulse, lower energy spread
2. Bunching by RF lattice (similar to cooling channel) into 200MHz
Ionization Cooling
With transverse focussing (solenoid) ~ beam envelope:
Rμ3
trans
xx
LmEβ
βf
L
ε
dz
dεHeating term (mult.scatt.)
Cooling term
x x
z zP1
P2
absorber
accelerator accelerator
absorber
P1
Multiple scattering
RF cavity RF cavity
The miracle of muons is that they can focus going through matter!
Phase space equation:
Liouville’s Theorem states that phase space is invariant.. need to remove energy to increase particle density…
LR large LH2
Transverse Cooling Channel Design
Shown here, a cooling cell with LH2 Absorbers, RF cavities and Solenoid Magnet:
Issues:LH2 safety, windows strong but thin, RF cavities
“benign”, structural intregrity in very large E and B fields
Ignition source: very high E fields!Incendiary
device (LH2)
Quench site: very high B
fields!
MuCool ResearchCurrent experiments at laboratories and universities.
LH2 WindowsPhotogrammetry:Non-contact measurement of strain by calculating displacement
Photogrammetry ~1000 points
Strain gages ~ 20 “points”
MuCool/ICAR researchCurrent design and simulation programs atlaboratories and universities.
Cooling channel RF cavities…
Large E fields inside of large B fields!
Large E field: cavity performance is determine by field emission from surface.
MTA LH2 Experiment
Beamline: C. Johnstone
Mucool Test Area LH2 Setup
Lab G magnet
MICE
T.O.F. IIIT.O.F. IIIPrecise timingPrecise timing
Electron IDElectron IDEliminate muons that decay Eliminate muons that decay
Tracking devices: Tracking devices: He filled TPC-GEM (similar to TESLA R&D)He filled TPC-GEM (similar to TESLA R&D)or sci-fior sci-fiMeasurement of momentum angles and positionMeasurement of momentum angles and position
T.O.F. I & IIT.O.F. I & IIPion /muon IDPion /muon IDprecise precise timingtiming
201 MHz RF cavities
Liquid H2 absorbersor LiH ?
SC Solenoids;Spectrometer, focus pair, compensation coil
Muon Ionisation Cooling Experiment: Approved by RAL
Technical Design Report in December
Muon Acceleration
Needs to be fast – muon lifetime
Needs to be a reasonable cost – not all linacs all the way
Baseline: Recirculating Linear Accelerators
• Other possibilities…… FFAGs & VRCS
FFAGs
• Fixed Field Alternating Gradient magnets not ramped
krB ~
Cheaper/faster RLAs/RCSs
Large momentum acceptance
Large transverse acceptance less cooling required!
Neutrino Factory Neutrino Factory
Japanese staged physics Japanese staged physics programprogram
• High Power Proton Driver– Muon g-2
• Muon Factory (PRISM)– Muon LFV
• Muon Factory-II (PRISM-II)– Muon EDM
• Neutrino Factory– Based on 1 MW proton beam
• Neutrino Factory-II– Based on 4.4 MW proton
beam• Muon Collider
FFAG’s
Proof Of Principle machine built and tested in Japan.
50keV to 500keV in 1ms.
150MeV FFAG under construction at KEK.
VRCS
Fastest existing RCS: ISIS at 50Hz 20ms
Proposal: accelerate in 37s 4.6kHz
Do it 30 times a second
920m circumference for 4 to 20 GeV
Combined function magnets 100 micron laminations of grain oriented silicon steel 18 magnets, 20T/m
Eddy currents iron: 100MW 350kW Eddy currents cu : 170kW
RF: 1.8GV @ 201MHz; 15MV/m
Muons: 12 orbits, 83% survival
Parting Remarks
Neutrino oscillations: one of most important physics results
Many new experiments conceived
New beam neutrino facilities required :- Superbeams - - Neutrino Factory- Beta beams
All require extensive R&D
For Neutrino Factory: a thriving research program- proton driver
- target - cooling (MuCool, MICE)
- acceleration
Real Experiments are planned and approved