Transcript JTO`s perspective and investment in HEL systems

JTO’s Perspective and Investment
in High Energy Laser Systems
8 Nov 2004
LCDR Rich Nguyen
NAVY Rep, HEL JTO
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Outline
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JTO Organization
JTO Portfolio
JHPSSL
FEL
FY05 S&A Call for Papers
MRI
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JTO Programmatic Organization
DUSD(S&T)
Technology Council
Contractor
Technical
Support
S&T Executives
(Army,Navy, AF,
MDA, DARPA, DTRA)
Director, Joint
Technology Office
Executive
Assistant
Army
Representative
Tech Area,
Contracts Monitor
Budget/Finance
Navy
Representative
Air Force
Representative
Tech Area,
Contracts Monitor
Tech Area,
Contracts Monitor
MDA
DARPA
DTRA
USMC Reps
Technology Area Working Groups
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JTO Mission, Vision, and
Objectives
• Mission:
To lead DOD’s development of HEL weapon
technology
• Vision:
Lasers will be a viable weapons in modern warfare
• Objectives:
Make HELs Lightweight, Affordable, and
Supportable
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JTO Thrust Areas
Laser Device
Thermal Management
- Solid State
- Chemical
- Free Electron
- Advanced
Heat
Beam
Combining
Beam Control
Lethality
Atmospheric Propagation
- Thermal Blooming
- Turbulence
Laser-Target
Interaction
Pointing
Beam Conditioning
& Adaptive Optics
Heat
Power Conditioning
Wavefront
Sensor
Windows &
Mirrors
Engagement
Modeling
Illuminator
Fire Control
Example: Solid
State Laser
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JTO Portfolio
• JTO maintains a portfolio of approx 80
Projects/Programs
• Addresses all thrust areas of HEL system
• Typical program size is $1M/yr
• Have larger programs in Electric Laser
Initiative
 JHPSSL
 FEL
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JTO Investments
(Larger Programs)
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JTO – 25KW JHPSSL
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AFRL – 25KW JHPSSL
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$26M (FY03/04)
JTO – 10KW Free Electron Laser
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$10.2M (FY03/04)
Army – 25KW JHPSSL
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$15M (FY03), $15M (FY04), $3.7M (FY05)
$4M (FY03), $4M (FY04)
Navy – 10 KW Free Electron Laser
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$14.1M (FY03/04)
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Joint High Power Solid State
Laser Program (JHPSSL)
Mission: to significantly accelerate development of
solid state laser technology for future High Power
Tactical Laser programs
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Near Term Goal: Demonstration and Fabrication of a 25 kW
Laser System with near diffraction limited beam quality and
useful metrics
Ultimate Goal: Demonstration of 100 kW Militarily
Significant Laser System
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JHPSSL Technical
Requirements
SOA: P=500W, BQ=1.1xDL, Eff<5%, <2W/kg
Parameter
Desired Value
Development Goals
Output Power
 25 kW
> 100 kW
Beam Quality
<1.5 xDL (goal: 1.2)
1.1 x DL
Run Time
 300 s
300 s
Start-up Time
 1 s (goal: 100 ms)
10 ms
Wall-Plug Efficiency
> 10 %
> 20%
Output Power-to-Mass
20 W/kg
50 W/kg
Beam Jitter
5%
5%
Temperature Range
Operate: 5 to 35 °C
Store: –29 to 49 °C
Operate: 5 to 35 °C
Store: –29 to 49 °C
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JHPSSL
Program Plan
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25 KW lab demonstrations is scheduled in Jan-Mar
2005 at all three facilities (LLNL, Raytheon, NGST)
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Raytheon & NGST contracts are fully funded
LLNL will need 1QFY05 funds from Army
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Gov’t team (MIT/LL, JTO, ARL, SMDC, & AFRL)
perform BQ and power measurements at each
facility, Mar 2005
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100KW RFP plan in 3QFY05 (open competition); Tech
Council decision for contract(s) award Sep 2005
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BAA solicitation/ technical criteria set by joint team
FY05 JTO funds available for kick-off effort
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FEL -- Surface Navy Threats
Protection
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FEL
Tactical System Goal
Injector & Accelerator
Top Level
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Power = 1 to 3 MW, controllable
down to 100 kW
λ = 1 - 3 µm
BQ < 2 times diffraction limit
Duty Cycle = 30 seconds run time,
repeatable after 5 minutes
 ~ 0.5 Amp average current & ~ 0.5 nC/bunch per MW
 2 °K Superconducting RF (500 - 750 MHz) linac
 100 MeV Beam with Energy Recovery
Wiggler & Resonator
 Short Rayleigh length
 1% - 2% Extraction efficiency wiggler
 Near concentric resonator
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MW-Class FEL
Key Technical Issues
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Photoinjectors with ~ 1 A average current, ~ 1 nC/bunch injector
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Development needed to achieve all requirements simultaneously
Issues with photocathodes, drive lasers, and emittance control
Anchored Models & Simulations
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Coherent synchrotron radiation (CSR) and other beam break-up effects degrade
the electron beam quality when focusing & bending
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Efficient wiggler & compact, survivable optical resonator
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Where are the limits? - More data & better models are required to manage effects
High intracavity power & small beam stress conventional resonators & optics
Need short Raleigh length wigglers, resonator concepts & improved optics/coatings
Propagation efficiency of an intense FEL beam
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Effects of maritime and other tactical atmospheric paths not yet adequately
understood
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Effect of the FEL pulse format on beam propagation (degrade or enhance?)
Optimum FEL concept for scale-up
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Trades required to balance the challenges faced by the evolving subsystem
requirements and competing approaches
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FEL
Photo Injectors
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Three classes of potentially scalable Photo Injectors are
being developed
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DC guns (Jlab & AES)
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Accelerate the electron bunch using a DC electrostatic field (~500 kV)
Inject 500 kV electrons into SRF cavity to accelerate to 5 – 10 MeV
Have demonstrated continuous (hi rep-rate), low charge/bunch operation
Challenge: large charge/bunch without space charge effects degrading emittance
Most mature, probably leading candidate for 100 kW FEL
RF guns (LANL & AES)
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All generate free electrons by striking a photocathode emitter with a pulsed laser beam
All need robust, long life drive lasers and high QE photocathodes in visible
Accelerate/control the electron bunch using RF fields & focusing magnets
Uses normal conducting RF accelerators if are required
Have demonstrated low rep-rate, high charge/bunch operation
Challenge: thermal management of room temperature RF accelerator at high accelerator
gradient
Less mature than DC gun, probably lowest risk for MW FEL
SRF guns (BNL & AES)
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Accelerate the electron bunch using RF fields in SRF linac cavities
Cryogenic photocathode
Challenge: thermal management of cryogenic and superconducting portions of the injector
with high power drive laser beam and high average current
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Least mature but best fit to SRF FEL if technical challenges can be addressed
FY05 S&A Call
FEL
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FEL: 01) High Average Current Electron Gun and
Injector Technology
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FEL: 02) Amplifier Technology Development
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FEL: 03) Technologies To Reduce FEL Construction
Costs
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FEL: 04) Compact RF Sources
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FY05 S&A Call
FEL: 01
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FEL: 01) High Average Current Electron Gun and
Injector Technology
“ Proposals in this area should address technologies
that support low-emittance consistent with 1 micron
wavelength FELs and average currents approaching
1 ampere. Robust electron gun technology, e.g.
employing photocathodes, is required that permits
long term operation in realistic vacuum environments
with a quantum efficiency leading to workable power
requirements for the cathodes drive laser.
Superconducting and normal conducting
technologies are of interest.”
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Multi-Disciplinary Research
Initiative Projects
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High Average Power Diode Pumped Solid State Lasers
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Affordable High Energy Laser Systems
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PM: Michael Berman, Air Force Office of Scientific Research
Principal Investigator: Dr. William McDermott, Denver University
High Power, Closed-Cycle Chemical Lasers
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PM: Arje Nachman, Air Force Office of Scientific Research
Principal Investigator: Dr. Jerry Moloney, University of Arizona
High Power, Closed-Cycle Chemical Lasers
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PM: John Zavada, Army Research Office
Principal Investigator: Dr. Robert Byer, Stanford University
PM: Michael Berman, Air Force Office of Scientific Research
Principal Investigator: Dr. Wayne Solomon, University of Illinois UrbanaChampaign
Atmospheric Propagation & Compensation of HEL
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PM: Kent Miller, Air Force Office of Scientific Research
Principal Investigator: Dr. Steve Gibson, University of California-Los Angeles
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Multi-Disciplinary Research
Initiative Projects (Cont’d)
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High Power, Lightweight Optics
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PM: Charles Lee, Air Force Office of Scientific Research
Principal Investigator: Dr. Hubert Martin, University of Arizona
FEL -- High Quantum Efficiency Robust Dispenser Photocathodes
PM: Quentin Saulter, Office of Naval Research
 Principal Investigator: : Dr. Patrick O'Shea, University of Maryland
Issues: Photocathodes are a weak link in FELs
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Goal: High quantum efficiency, robust dispenser photocathode using green light
or IR drive laser
Approach: Theory and Experiment with a focus on dispenser photocathodes
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FEL -- Diagnostics & Control Methods
PM: Quentin Saulter, Office of Naval Research
 Principal Investigator: Dr. Todd Smith, Stanford University
Issues: Need Better Phase Space Mapping techniques for High-Quality Beams
Goal: Develop techniques for measuring high average current beams that are
suitable for interface with control system
Approach: New schemes using: Optical Diffraction radiation, Optical pepper
pots, Optical synchrotron interferometry
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Questions?
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