R&D100 Award Winner:
High Flux Fast Neutron Source
A team of scientists at
Adelphi Technology and
the University of Florida
Training Reactor have
developed a neutron
source that produces
high fluxes of fast
neutrons that are 100
times greater than those
produced by other sources. These fluxes are
large enough to analyze fissile and high density
materials. The generator has a long lifetime
and can to be used in small laboratory settings.
2003 E. Bayshore Rd,
Redwood City, CA 94063 USA,
Improved High-power X-rays
The excellence of brilliant x-ray beams produced by the
latest generation of synchrotron radiation facilities is
undermined by the difficulty of keeping intense x-ray
beams co-located with samples to sufficient precision.
Long optical paths and widely spaced reflective elements mean that small relative displacements will
cause large displacements and defocusing. With
the introduction of the NanoBPM, scientists
at Univ. of Manchester and FMB Oxford Ltd.
have invented a diagnostics method for intense,
highly collimated x-ray or particle beams that allows a non-destructive method of characterizing the beam
in full detail, without placing a detector into the beam where it would suffer from radiation damage.
The in situ, or transparent, system uses an off-axis coded aperture camera that provides a magnified
image of the beam cross-section, enabling beam positioning with high precision. The new method
magnifies any motions of the beam position, allowing highly precise beam position measurements.
Unique geometry and lensless imaging using coded apertures provide a simple way of magnifying
beam movements by a factor of up to 30 times, resulting in sub-micrometer precision of beam position measurement.
; Univ. of Manchester, http://www.manchester.ac.uk
Lithium Crystal Corrals
Traditional thermal neutron detectors are proportional counter tubes, filled with helium or boron
trifluoride, which react with impinging neutrons
and generate a charge proportional to the Q-value,
or energy value, of the reaction. They have a host
of uses in security, defense and nuclear safety; but
the gases used are either highly toxic or in increasingly short supply.
LISe: A High-Efficiency Thermal Neutron
Detector, developed by Y- 12 National Security
Complex and Fisk Univ., offers an alternative to
existing technologies. LISe contains the neutron
absorber within the semiconductor itself. LISe,
based on the 6LiInSe2 crystal, is the first large,
single-crystal lithium semiconductor of high resistivity that directly detects thermal neutrons. Every
fourth atom in the semiconductor is lithium, so
the average distance traversed by a thermal neutron before capture by the detector is just 0.1 mm.
This enables a factor-of- 25 improvement in both
detector thickness, compared to helium tubes, and
efficiency, compared to coated-silicon diode.
; Y- 12 National Security Complex,
Maximum Flux for Fast Neutrons
Analysis of nuclear materials using fast neutron sources has
become more common. Greater intensity, or flux (neutrons per
unit area), of these sources ensures more effective analysis. However, in current devices samples must be placed a distance from
the neutron source emitter where the flux of the fast neutron is
small. The “High Flux Fast Neutron Source” Model DD-109X,
introduced by Adelphi Technology Inc. and the Univ. of Florida, changes that by positioning the sample to be irradiated in
the acceleration chamber next to the high-voltage target that
produces the fast neutrons. This produces fluxes of fast neutrons
that are 10 to 100 times greater than those produced by alternatives that use the same deuterium-deuterium fusion reaction.
This is high enough to analyze fissile materials, and permits
long-term analysis. Long life also reduces operating costs.
; Adelphi Technology Inc., http://www.adelphitech.com
Compact, Lightweight X-ray Scans
X-ray scanners are, even after decades of development, bulky, heavy,
expensive and not always reliable. Los Alamos National Laboratory, with
the help of several industry experts in optics, has introduced an x-ray
device, MiniMAX, that overcomes these limitations. MiniMAX
(Miniature, Mobile, Agile X-ray system) is light, portable, relatively
inexpensive and robust. A point-and-shoot device that records on
conventional storage phosphor screens, it uses no consumables, no
chemicals and little power. Several industry leaders in optics contributed hardware to build the system. Leica Camera AG produced the
world’s lightest, most compact, 35-mm monochrome digital camera.
JDS Uniphase contributed high-performance dichroic filters that have
a rejection ratio of more than a billion-to-one. Jenoptik Optics LLC
produced a special-purpose, fixed-focus lens for MiniMAX that mixes
high resolution with high speed in a lightweight package. These components enable MiniMAX to seamlessly perform a remarkable x-ray to
; Los Alamos National Laboratory, http://www.lanl.gov