College of Science
University of Nevada, Reno
Department of Physics
Nevada Terawatt Facility
APPLICATION FOR THE JULY – DECEMBER 2014
EXPERIMENTAL CAMPAIGN SEASON
AT THE NEVADA TERAWATT FACILITY USING THE
ZEBRA Z-PINCH PULSED-POWER GENERATOR
and/or THE LEOPARD TERAWATT LASER
JULY 21, 2014 – DECEMBER 19, 2014
(REQUESTS DUE AT NTF BY MAY 9, 2014 @ 12:00 P.M.)
Must be submitted in WORD format ONLY
Dear Colleagues,
Interested Researchers are encouraged to submit a request for time during the next experimental
cycle on the Zebra and Leopard systems at the Nevada Terawatt Facility. Experimental
campaigns are scheduled to begin on or about JULY 21, 2014 and proceed through DECEMBER
19, 2014.
The NTF has performed experiments in the following areas as part of its scientific portfolio:
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Nonlinear development of magnetic Rayleigh-Taylor instabilities, i.e. interchange
instabilities in high-beta plasmas with inhomogeneous magnetic fields.
Sheared plasma flows.
Warm dense plasmas and isochoric heating of solid-density plasmas.
Kelvin-Helmholtz flow instability in strongly magnetized plasmas.
Flyer-plate acceleration for shock generation in steep gradients.
Linear Current Multiplier (LCM) operations.
Plasma formation and radiation features of multi-planar wire arrays.
Studies of wire-array z-pinches at the stagnation phase.
Mechanisms of plasma heating in wire-array z-pinches.
Atomic processes in astrophysical plasmas produced by Zebra.
The development of doped target materials for NTF experiments.
Using the Leopard terawatt laser for x-ray backlighting and development of x-ray
absorption spectroscopy in z-pinch plasmas.
The development of novel plasma diagnostics on Leopard and Zebra which support the
NTF mission.
We encourage everyone to present experimental campaign requests with these research areas in
mind.
Included in the application package is a request form for experimental time on the Zebra and/or
Leopard instruments. NTF will accept experimental campaign requests for this cycle starting on
April 4, 2014 and extending through May 9, 2014 at 12:00 p.m. The requests will be reviewed
and experimental campaign times allocated on or about May 23, 2014. This schedule should
allow enough time to prepare and execute approved experimental requests.
The scientific merit of the proposed research project will be assessed along with project
feasibility. Requests are limited to three pages (Abstract, Anticipated Outcomes and Proposal).
Exceeding the three-page limit can be grounds for removing the experimental campaign request
from consideration.
Judging Criteria for these experimental campaign requests are as follows:
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Grants proposal – priority for experiments with date constraints or other
commitments.
Coupled high-intensity laser / Zebra experiments.
Zebra experiments whose focus is basic understanding or applications of Zpinches.
Stand-alone, high-intensity laser-target experiments (other than those
including Zebra) which support the NTF mission.
Zebra experiments supporting traditional fusion concepts supported by
NNSA or the Office of Fusion Energy Sciences.
Other high-quality scientific proposals with priority to those supporting highenergy-density physics.
Financial restrictions – Cost to NTF.
Lead time – on critical supplies, design and fabrication.
Facility availability – maintenance, upgrades, and installations.
Experiments should be designed to answer specific questions of interest to the HEDP community
as outlined in major HEDP documents1,2. Other types of experiments falling outside these
criteria will require pre-consultation with NTF management. Proposals should answer the
question, “Why are the results of the proposed experiment important?”
Requests with significant student involvement and leadership are encouraged. Proposals must
include an explanation of how the experiment will contribute to the Ph.D. dissertation(s) or
Master’s Theses of participating graduate student(s).
NOTE: Changes in the NTF’s budgetary environment may result in the NTF Director arbitrarily
changing the above judging criteria. Under certain circumstances, priority may go to proposals
involving students who are close to graduation.
Experimental campaign requests should be submitted electronically in Word format only to:
Ferguson@unr.edu
Please forward this message to your collaborators or colleagues who are not on this mailing list.
Thank you
Aaron Covington
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Basic Research Needs for High Energy Density Laboratory Physics, Report of the Workshop on HEDLP Research
needs, November, 2009, U.S. DOE FES & NNSA.
2
Report of Research Needs Workshop (ReNeW), 2009, U.S. DOE OFES.
Nevada Terawatt Facility
Application for Experimental Time on Zebra / Leopard
July 21, 2014 – December 19, 2014
Title:
Date:
Grant Number and Title (for grant-supported efforts):
Lead Scientist:
Student Participation:
Contact Information (phone # & e-mail):
Collaborating Scientists and Affiliations:
Type of Experiment (e.g. Zebra only, Leopard Laser only, Coupled Zebra/Leopard):
Requested number of shots:
Requested number of days to complete experiment:
Scientific Theme:
Suggested Dates not available1:
Requested Core Diagnostics:
1
Note that any proposal, regardless of merit, may not be allocated campaign time if too many restrictions are placed
on available dates. Campaign time is also subject to machine availability.
Guidelines
1) Indicate Zebra / Leopard operating parameters, and port requirements anticipated for
diagnostic instruments.
a)
Load measurements (standard or custom)
b)
Pulse duration – Long or Short
c)
Chamber Requirements – (ports, location of diagnostics equipment)
d)
Screen Box requirements
2) Describe any special needs that are relevant, such as equipment, cables, fast or slow
trigger signals, tools.
3) A clear statement of scientific importance; why are NTF facilities needed and if so
what characteristics are most important. Include scientific deliverables and a clear path
for achieving these deliverables
4) Mechanical drawing: Electronic or manual drawings are acceptable. The design
should be as complete as possible. NTF Technical Teams will work with the
experimenter(s) to assure compatibility with zebra and the goals of the experiment.
5) Vacuum test certification: All instruments intended for attachment to the Zebra load
chamber must be certified in advance for vacuum integrity. NTF Technical Staff will
work with experimenter(s) to assure compatibility.
6) Budgetary requirements must be estimated. An approved experimental campaign does
not obligate the NTF to support campaign costs. Researchers must coordinate with NTF
management to clarify level-of-support.
Abstract (One Page)
Anticipated Outcomes (One Page)
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Proposal (One Page)
Equipment, Materials, Engineering & Budgetary Requirements
(This must be completed)
Engineering Requirements
(Mechanical drawing, vacuum test certification, etc.)
1)
2)
3)
Materials
(Disclose all materials comprising loads and diagnostics instruments. Experiments that
require the use of certain hazardous materials will be sampled and/or monitored so that
non-exposure documentation can be completed).
1)
2)
3)
Equipment
1)
2)
3)
Leopard Laser
Laser parameters
Pulse energy – up to 12 J;
Pulse duration - 350 fs;
Wavelength - λ0=1056 nm, Δλ = 6 nm;
Beam diameter - 8.6 cm;
Rate of shots (disk amplifier cooling) - 1/ 40min;
Contrast ratio (ASE) - 106.
Alignment beam (from the regenerative amplifier)
λ0=1056 nm, ν = 100 Hz
Laser beam diagnostics
Energy
Near Field
Far Field (with parabola, F=15cm)
Pulse duration (FROG)
Contrast ratio
Vacuum beam paths from the compressor to vacuum chambers
Experimental areas
(Supported by the principal experimentalist)
Phoenix vacuum chamber
Lens focusing system, F=30-100 cm
Al parabola mirror, F=15 cm
Targeting positioning system
Zebra vacuum chamber
Lens focusing system, F=80-110cm
Targeting system
Zebra
Load current
Regime
Short pulse
Long pulse
Maximum current intensity
1 MA
0.6 MA
Current rise time
100 ns
200 ns
The Zebra current depends on load characteristics. The maximum current intensities cited are
measured with standard short-circuit loads. Their geometry is available upon request.
In the short-pulse regime, the current has a pedestal that increases approximately linearly for
about 100 ns to about 50 kA.
Load vacuum chamber
The walls of the vacuum chamber function as the current return path. It is not recommended to
place any component in the high-field region. The minimum safe distance for diagnostics is 30
cm from the chamber axis.
Sixteen diagnostics ports, equally spaced at 22.5 degrees, with alternating diameters of 7.6 cm
and 4.4 cm are available. Diagnostics access along the z-axis and at 9 degrees to the axis is also
available.
Synchronization
Trigger pulses with jitter lower than 5 ns rms with respect to the maximum load current intensity
are available for diagnostics that require delay time shorter than 350 ns. If the delay required is
longer, the trigger pulse available has a 25-ns rms jitter.
Other information
A vacuum of at least 4×10-5 Torr (or better) in the Zebra experimental chamber is required for
the Zebra to operate. The anode-cathode gap shrinks ~ 1 mm during vacuum pump-down.
In the short pulse configuration, the load region is accelerated to more than 300g during the shot.
The feasibility of any proposed modification of the Zebra set-up must be discussed in a timely
manner with the technical team.
Diagnostics
Laser diagnostics
Diagnostics: shadow and/or schlieren diagnostics along two lines of sight at 22.5 degrees from
each other; two pulses separated by a variable delay along each line-of-sight. Total pulse train
duration: 9 ns or 34 ns.
Laser parameters: 532-nm wavelength, 150-ps pulse duration.
Support is available in the operation of the laser diagnostics.
Support may be available for the set-up of delay lines and the magnification of optical systems.
Visible-light diagnostics
Time-gated intensified CCD camera (iCCD) with exposure time longer than 2 ns (3 ns 1-σ jitter).
Streak camera (30 ns 1-σ jitter).
X-ray diagnostics
Time-gated pinhole camera (film detection)
Time-gated spectrometer (convex KAP crystal, film detection)
Time-integrated spectrometer (convex KAP crystal, film detection)
Bolometer (Ni or Au)
Filtered Photoconductive detectors (PCD)
Filtered X-ray diodes (XRD)
The bolometer and a combination of PCDs and XRDs installed in 5-channel heads (two such
detector heads are available).
Support with installing and operating theses devices (including setting delays, applying biases,
filter replacement and film development) is available from the NTF Technical Team. The
Technical Team is also available to train the experimental team on these tasks.
Instrumentation
Oscilloscopes
Delay generators (DG 535, BNC 500, Quantum)
Low voltage power supplies
High voltage power supplies
Other information
Magnetic protection of several diagnostics beam lines is available upon request.
Installation of any other diagnostics instruments must be coordinated in advance with the
technical team.
Operations
Hours of Operation
Zebra operations: Monday through Friday (Hours: 9:00 am – 5:00 pm).
Requests to extend the above daily schedule may be considered, and are subject to operational
and budgetary constraints.
Operational and Planning Considerations
By NTF policy, technical staff support is available to support actual campaign operations no
earlier than 8:00 am on the first scheduled day of the campaign. The facility is not generally
available to the PI (or the research team) for set-up or actual campaign operations prior to that
time. Access to the NTF facility for set-up and/or operational support prior to that time must be
coordinated in advance with the Director of Scientific Operations.
There is no “standard” configuration for NTF research machines. The NTF will normally
configure its major research instruments to most effectively meet the needs of a variety of users
while maintaining a high scientific throughput. Because of the fluid and changing nature of this
type of scientific research, The NTF cannot guarantee the configuration of the facility and the
major research machines for specific campaign operations at the start of any particular campaign.
In general, each team should expect 1-2 days of set-up on the front end of each campaign. In
planning experimental campaigns, the PI should account for any and all set-up time needed at the
beginning of the campaign to put the Zebra and/or Leopard into desired configurations, to
emplace needed diagnostics, or to install/uninstall additional campaign-specific equipment.
Campaign operations terminate at 5:00 pm on the last scheduled day of the campaign. The
facility will no longer be available for the campaign after that time unless prior arrangements are
made with the Director of Scientific Operations. It is expected that PIs will ensure that their own
“individual” equipment is removed as quickly as possible as a courtesy to subsequent
researchers, and PIs should allow for time to do so in their campaign planning. PIs must have
“individual” equipment removed no later than 8:00 am of the next business day. Access to the
NTF facility during non-business hours for post-campaign activities (e.g., equipment breakdown, etc.) must be coordinated in advance with the Director of Scientific Operations.
As soon as practical, the NTF will publish a fall experimental campaign season calendar. The
NTF strongly encourages coordination between PIs of adjacent campaigns to ensure a smooth
transition from one campaign to the next and to help minimize lost shots due to excessive
machine reconfiguration.
A pre-campaign coordination meeting between the Research Team and the NTF Technical Staff
will take place on-site approximately two months prior to the start of all approved experimental
campaigns. Daily operations meetings will take place each and every day of the actual campaign
(usually) at 8:45 am. The PI or a knowledgeable member of his team must be present at these
meetings to coordinate operations and support for the day.
Campaign time is subject to machine availability. The PI assumes all risk for unanticipated
delays. The NTF does not guarantee that time lost due to maintenance or related issues will be
made up.
Budgetary constraints may preclude the NTF from providing material and supplies that have
been traditionally provided in the past. The constrained budgetary environment expected for
calendar year 2014 may also adversely affect the pace of operations.
Training of the experimental teams in operational tasks (e.g. chamber set-up, safety operator) is
available.
For more information, contact
Dr. Aaron Covington, acovington@unr.edu