Transcript Lab/University Accelerator R&D Partnerships

Lab/University
Accelerator R&D Partnerships
(Models, Progress, & Opportunities)
Gerald C. Blazey
Northern Illinois Center for
Accelerator and Detector Design
(http://nicadd.niu.edu)
Northern Illinois University
Jerry Blazey
NICADD/NIU
Why?
• An interesting field in its own right, with interesting
challenges and questions.
• Shortage of qualified physicists and resources
committed to design of new machines and technologies.
• For the linear collider in particular
– Many of the unresolved technical issues are ideally suited for
contributions from university groups.
– HEP material and intellectual resources will be required.
• Involvement of university will foster innovation,
increase number of qualified individuals, leverage
resources.
(there is a well developed program for advanced concepts)
Jerry Blazey
NICADD/NIU
Representative Efforts
• Illinois Consortium for Accelerator
Research (ICAR).
• The Fermilab/NICADD PhotoInjector
(FNPL)
• Single University/Laboratory Partnerships
Opportunities
• The linear collider research topic database
• The evolving consortia & working groups
Jerry Blazey
NICADD/NIU
Illinois Consortium of Accelerator Research
• 1999 - IIT organized university consortium to assist
Fermilab w/ future technologies
• 2000 - IIT, NIU, NW, UC, UIUC received funding from
state of Illinois and NSF.
• Current budget ~$2.5M/yr
– which supports in whole or part ~25 faculty /
scientists.
– has resulted in three new accelerator faculty
positions.
• Groups loosely organized by Executive and Advisory
Boards.
• Pursue topics collaboratively and independently.
• Almost all have backgrounds in HEP.
Jerry Blazey
NICADD/NIU
Activities
• Neutrino factory feasibility studies I & II.
• Proton driver physics and design studies.
• Muon cooling (as part of MuCool Collaboration) effort instructive
– Simulations and theoretical investigations
– Absorber development and engineering
– Fast Instrumentation
– RF cavity mechanical design
– Fermilab linac test beam
• Linear Collider
– Vibration studies
– Photoinjector R&D for LC
– g-g collider studies (at SLAC)
• Outreach: surveys, citizen involvement
Jerry Blazey
NICADD/NIU
Comment on Structure
• HEPAP has recommended advanced R&D.
• The NSF funding for ICAR was part of a
Muon Cooling joint proposal led by Cornell
–
–
–
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Component Construction: ICAR, Mississippi
Theory: Cornell, MSU
Simulations: Indiana, Columbia, ICAR
200 MHz SC Cavity: Cornell
• The “subcontracting” structure successfully
advanced project.
Jerry Blazey
NICADD/NIU
“4-dim. cooling”
sufficient for a
neutrino factory.
“6-dim. cooling”
required for a
muon collider.
d n
1 dE  n
1   (0.014) 2
- 2
 3
ds
 ds E  2 E m LR
Jerry Blazey
NICADD/NIU
Cooling Channel Design
Quench
site
LH2 under
Pressure
Ignition
source
A cooling cell with LH2 Absorbers, RF cavities and
Solenoid Magnet
Jerry Blazey
NICADD/NIU
Photogrammetric studies of window (minimum heating, heat
management, safety or burst tests)
Focus has
been on
component
testing here
the window.
Beam detection and
profiling using bolometry
(strips of material on the
absorber window that
change resistance when
radiated.)
Jerry Blazey
NICADD/NIU
Dark current due in high gradient 800 MHz RF cavity within a
solenoid destroys Plexiglas windows.
Jerry Blazey
NICADD/NIU
Proton Linac Absorber Tests
Tests heat and current
capabilities of components
ICAR: FTEs & Capital Equip.
FNAL: FTEs & Site
Jerry Blazey
NICADD/NIU
Ground Stability at Fermilab
• Coordinated by SLAC.
• NW purchased equipment & will participate.
Portable Data
Recorder DL-24
Broadband Three-component
Seismometers KS-2000
• NUMI tunnel motion vs. depth measurements start
in July.
Jerry Blazey
NICADD/NIU
Fermilab/
Photoinjector
Laboratory
• An electron source at A0 location
• Starting 2001 jointly operated by Fermilab/NICADD
• Missions:
– Investigation of beam physics
– Development of beam diagnostics Training of
Acc. Phys.
– Simulations
• An international facility (ICAR: Chicago, Georgia,
Michigan, Pennsylvania, Rochester, Fermilab, DESY,
CERN, LBNL)
• About 50% of the university types from HEP
Jerry Blazey
NICADD/NIU
Jerry Blazey
NICADD/NIU
FNPL University Activities
• Theses
– Five completed
– Three current
• Beam Physics
–
–
–
–
–
Flat Beam Studies
Plasma Wakefield Acceleration
Laser Acceleration
Studies of Space Charge
Coherent Synchrotron Radiation Studies
Simulations
• Electron Beam Diagnostics
– Interferometric bunch length measurements
– Electro-optics
• Open to new collaborators, ideas!
Jerry Blazey
NICADD/NIU
Dissertations
• Completed
• E. R. Colby, Ph.D., UCLA, 1997. Design, Construction, and Testing of a Radiofrequency Electron
Photoinjector for the Next Generation Linear Collider. RF guns currently operating at Fermilab and
DESY were constructed in the course of this work.
• A. Fry, Ph.D., Rochester, 1996. Novel Pulse Train Glass Laser for RF Photoinjectors. Design and
initial performance of the laser at the Fermilab photoinjector.
• S. Fritzler, Diplomarbeit, Darmstadt, 2000. This thesis covers the first observation of channeling
radiation in the high flux environment of A0, and extends observations as a function of bunch charge
two orders of magnitude higher than any earlier measurement.
• M. Fitch, Ph.D., Rochester, 2000. Electro-Optic Sampling of Transient Electric Fields from
Charged Particle Beams. In addition to the discussion and measurement of wakefields induced by
bunch passage through the photoinjector, further data on laser and injector performance is given.
• J.-P. Carneiro, Ph.D., Universite de Paris-Sud, 2001. Etude experimental du photo-injecteur de
Fermilab. This is a thorough documentation of the performance of the photoinjector, including
comparison with the predictions of E. Colby.
• Current
• D.Bollinger, NIU, Plasma Acceleration
• R.Tikhoplav, Rochester, Laser Acceleration.
• Y-e Sun, Chicago, Flat Beams.
Jerry Blazey
NICADD/NIU
Flat Beams
• LC specifications: x=300nm, y = 5nm.
• A non-zero magnetic field at photo cathode imparts angular
momentum to beam
• Skew quadrupole triplet transforms round beam to flat beam
• Key Question: How to optimize beam quality with flat-beam
transformation?
• Goal (eliminate
e-damping ring):
εy/εx ~ 100 with
εgeom ~ 1 μm/nC.
• Achieved to date:
εy/εx ~ 50 with
εgeom ~ 6 μm/nC
Jerry Blazey
NICADD/NIU
Plasma Wake-field Acceleration
Accelerated electrons up to 20.3 MeV
Decelerated electrons down to ~3 MeV:
Principle:
• e-beam punches structures in plasma
• part of the beam is accelerated
Parameters:
• Charge: 6-8 nC
• Bunch length: < 1 mm RMS
14
• Plasma: L=8cm, 10 /cc density
• Initial energy: 13.8 MeV
• Acceleration gradient: 72 MeV/m
Simulated energy spectrum
Jerry Blazey
NICADD/NIU
Laser Acceleration of Electrons
• Study the possibilities of
using a laser beam to
accelerate charged particles
in a wave guide structure
with dimensions much larger
than the laser wavelength
• The laser operates in the
TEM01*
mode
which
provides the largest possible
longitudinal component of
the electric field.
• For 34 TW of laser power
(the maximum that that can
be supported by the structure)
the accelerating field Ea=0.54
GV/m.
Jerry Blazey
NICADD/NIU
Bunch Compression
• Coherent synchrotron radiation and other wake-fields
generally complicate bunch compression, e.g.,
microbunching can arise
• Energy fragmentation
of compressed bunch
as seen in FNPL:
Beam Energy ~ 15 MeV
Bunch Charge ~1 nC
• Dynamics are sensitive
to phase space input to
the bunch compressor.
E 
• Careful measurement
of input and output
longitudinal phase spaces is needed  FIR
interferometer to measure coherent synchrotron rad.
Jerry Blazey
NICADD/NIU
Simulations
• Complication: Space charge, rf focusing “ruin” the linear
round-to-flat transformation by introducing nonlinear
forces.
• Codes that include these nonlinear forces are, e.g.,:
PARMELA, ASTRA, HOMDYN.
• Canonical simplification: cylindrical symmetry ⇒ codes
must be generalized! Authors of ASTRA, HOMDYN are
working on generalizations.
• Working to benchmark generalized codes against FNPL
experiments. Ultimate goal is end-to-end simulation
Jerry Blazey
NICADD/NIU
Topics/Dissertations
http://nicadd.niu.edu/fnplres.html
•Electron-Beam Diagnostics
- electro-optic crystal
- Michelson interferometer
- diffraction-radiation
- deflecting srf cavity
• Superconducting RF Cavities
- “kaon-separator” (deflecting) cavity
- “beam-shaper” (accelerating) cavity
• RF Gun
- high-duty-factor (srf?)
- polarized beam
- dark current and photocathode
• Fundamental Studies of Space Charge &
Coherent Synchrotron Radiation
• Simulations
Jerry Blazey
NICADD/NIU
A High-Brightness Photoinjector
• A collaboration modeled on large detector
collaborations for the construction and
operation of a high-brightness electron beam
at Fermilab.
• Five year construction, then operation.
• Advanced beam research, diagnostics 
promotes university based research
• Have encouragement from Fermilab & ANL.
Site selection and timescales under discussion.
Jerry Blazey
NICADD/NIU
Notional Layout of Photoinjector
(as envisioned by DESY)
Emittance ~1 micron, Bunch Length <270 microns
A long term facility to study beam physics, diagnostics
(not an endorsement)
Jerry Blazey
NICADD/NIU
Example partnerships w/ Labs
• NLC structures at Fermilab – NIU
• Inertial anchor - University of British
Columbia
• Prototype intra-train beam-beam
deflection feedback - Oxford
• Many others….my apologies…
Jerry Blazey
NICADD/NIU
NICADD/ NIU Furnaces at Fermilab
Jerry Blazey
NICADD/NIU
Vibration Suppression R&D
• U of B.Columbia, Tom Mattison + 2 students
• Problem:
– LC requires 2 nm vertical stability of beam & final quadrupoles.
– Ground motion exceeds this at frequencies above 10 Hz.
– Quads on cantilever supports amplify ground motion.
• Possible Solution: Optical Anchor suggested by SLAC
– measure quad positions w/ interferometers
– correct positions/ with feedback.
• SLAC provides equipment
• First piece of
Piezo
engineering mockup
Mounts
• A comment: the quads
are in the detector,
contributions to this
should clearly “punch”
collaboration ticket,
why stop there?
Detector
Quads
Laser
Beams
Bedrock
Jerry Blazey
NICADD/NIU
Inertial Anchor Concept Test
Platform Position vs Sample
nm
Sample Number
10-meter interferometer
prototype
Jerry Blazey
NICADD/NIU
Feedback on Nanosecond Timescales
• FONT Collaborators: Oxford HEP group (Phil
Burrows + 2 postdocs + students), SLAC, KEK, Kicker
CERN.
• Problem: Beam offset must be 2 nm or less
Processors
• Solution: Use feedback between
Controls
beams to ensure deflection is zero.
• The challenge: Nanosecond
feedback on beam
BPM
offset to correct train.
• Simulation, design,
construction at
Oxford
Jerry Blazey
NICADD/NIU
NLCTA Prototype Tests
• Now running Xband BPM &
kicker to
demonstrate
feedback loop
and measure
latency.
• Will also migrate
to engineering
mockup
Beam direction
Feedback loop
Jerry Blazey
NICADD/NIU
The LC R&D List
• Organized by Tom Himel with input from Dave
Finley and Joe Rogers
• Database of accelerator LC R&D in response to
requests from the university community.
• Contains a wide variety of priorities, project
sizes, and needed skills.
• NLC, TESLA, and generic accelerator R&D
items are on the list
• On Web: http://wwwproject.slac.stanford.edu/lc/Project_List/intro.h
tm
Jerry Blazey
NICADD/NIU
Example
ID: 10
project_size: Medium skill_type: Monte Carlo
short project description: Background Calculation and Reduction in the
IR.
Detailed project description: There are many types of backgrounds:
Halo muons, low energy e+e- pairs, synchrotron radiation. Use
existing simulation tools (and perhaps write new ones) to calculate the
background levels and to design shielding and masks to minimize it.
Needed by who: NLC and TESLA present status: In progress, help
needed Needed by date: 6/1/2005
ContactPerson1: Tom Markiewicz WorkPhone1: 6509262668
EmailAddress1: [email protected]
Jerry Blazey
NICADD/NIU
Example
ID: 14
project_size: Medium skill_type: physicist
short project description: Damping Ring beam size monitor
Detailed project description: The beam height in the damping ring will
be about 4 microns. We need to non-disruptively measure this on an
individual turn in the ring. Traditionally this is done with a synchrotron
light monitor. The spot here is so small that one must go to very short
(x-ray) wavelengths to get the necessary resolution. We would like a
conceptual design of some way to do this. It would then be evaluated
whether a prototype is needed
Needed by who: generic accelerator Present status: need good
idea Needed by date: 6/1/2005
ContactPerson1: Marc Ross WorkPhone1: 6509263526
EmailAddress1: [email protected]
Jerry Blazey
NICADD/NIU
Example
ID: 38
project_size: Small
skill_type: Optics design
short project description: beam profile monitor via optical transition
radiation
Detailed project description: In low intensity beam lines (injector), and
possibly at the bunch length deflector cavity, measure the beam profile
on a single bunch. A prototype system (with somewhat different
parameters) is operating at the ATF.
Needed by who: generic accelerator present status: Prototype
done Needed by date: 1/1/2007
ContactPerson1: Joe Frisch WorkPhone1: 6509264005
EmailAddress1: [email protected]
Jerry Blazey
NICADD/NIU
Other Selected Topics
• Electronics standards – VME replacement
• Production of polarized positrons.
• Beam diagnostics
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–
–
–
–
Laser wire beam monitor
Inteferometry (Bunch Compression/Frag.)
Optical Transition Radiation
Polarimetry
Luminosity Monitors
• Remote Operations
Jerry Blazey
NICADD/NIU
A Diagnostic Interferometer
•
•
•
•
Optics diameter:
75 mm
Dimensions: 30cm x 15 cm x 15 cm
Frequency range:
3 cm-1 to 500 cm-1 (3.3 mm to 20 m).
Translation stage:
20 mm travel, 2 m accuracy
6.0”
11.0”
CTR:
S:
M1:
M2:
PM:
DET:
Coherent Transition Radiation
Beamsplitter
Mirror on Translation Stage
Fixed Mirror, Semi-Transparent
Off-Axis Parabolic Mirror
Detector Module
An opportunity for other
disciplines…
Jerry Blazey
NICADD/NIU
Interferometer Operation
(Fourier
transform)
Interferogram
Autocorrelation
Energy spectrum
Bunch Density
(Hilbert transform
of energy spectrum)
• Resolution of fine structure requires access to short wavelengths,
• Existing interferometers average over many bunches, not single shots.
Jerry Blazey
NICADD/NIU
Electro-Optics
[M.J. Fitch, et al., Phys. Rev. Lett. 87, 034801 (2001)]
•
Major Advantage: Noninvasive
(Does not intersect beam.)
•
Works via Pockels effect:
- Electric field modifies
dielectric tensor;
- Laser beam monitors
the modifications.
•
Potential: Direct time-domain
observation of beam field.
BUT – Chamber wakefield
must be small!
Jerry Blazey
NICADD/NIU
New Organizations
– Framework for university involvement in detector &
accelerator R&D on LC.
– Currently :
• 3 groups (Cornell, Fermilab, SLAC)
• 2 funding agencies (NSF & DOE)
• 1 Linear Collider
– Relationships evolving
• NSF groups naturally cluster under a single proposal
submitted by Cornell?
• DOE groups naturally cluster w/ Fermilab & SLAC
under a individual or single proposals?
• But work where convenient & communicate!
• Proposals vetted by the USLCSG Working Groups
Jerry Blazey
NICADD/NIU
History
• April 5th, Fermilab Meeting, 123 participants
• April 19th, University Consortium for the Linear
Collider @ Ithaca, 55 participants
• May 30th, Linear Collider R&D Opportunities @
SLAC, 106 participants
• June 27-30th , Santa Cruz
– Linear Collider Retreat w/ Acc. R&D Sessions.
– UCLC statements of interest
– Joint Fermilab/SLAC meeting
• September, NSF submission
Jerry Blazey
NICADD/NIU
Closing Comments
• There are successful models for significant,
university sponsored accelerator R&D
– University based consortia.
– Facility based collaborations.
– Single groups w/ laboratory support.
• We should broaden our definition of hardware
contributions to include collider components.
• There is ample opportunity to get involved, the
skill set, project scopes are similar to HEP.
• The new organizations offer opportunity!
• Need new support, either from the universities or
funding agencies – we need to move together.
Jerry Blazey
NICADD/NIU