11-12-2012, 02:09 PM
Antimatter Driven Sail for Deep Space Exploration
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Antiproton Annihilation
• On average, the annihilation
produces three 400 MeV charged
pions and three gamma-rays (from
neutral pion decay).
• On average, 1.25 pions are
absorbed by the nucleus, causing
the nucleus to recoil and fragment,
carrying on average 150 MeV.
• For heavier elements, annihilation
causes fission: Homeland Security!
• In living tissue, neutron annihilation
usually produces PET isotopes.
Phase II Role in Overall Enterprise
• No one grant or institution
is ready to devote sufficient
resources to develop
antimatter-based propulsion
concepts.
• To date we have funded
theoretical and
experimental development
efforts through a tag-team
approach between private
investors, DOE, NIAC, the
NASA Marshall Space
Flight Center Propulsion
Research Center, and Hbar
Tech.
Fermilab Overview
• The Fermi National Accelerator
Laboratory, also called Fermilab or
FNAL, is sited 40 miles west of
Chicago in Batavia, Illinois.
• Fermilab’s mission is to perform
high-energy particle physics, and
currently operates the highest
energy accelerator in the world (the
Tevatron proton-antiproton collider)
• The Main Injector accelerates
protons to 120 GeV and directs them
into the antiproton production target.
• The Antiproton Source accumulates
and cools the antiprotons.
Antiproton Production @ Fermilab
• Present: 1011 antiprotons/hour for 4500 hours per year.
• Present: 27.4 M$/year for purchase of all antiprotons.
• Basic Research: At present, research that is published in
peer-reviewed journals are the subject of collaborative
agreements wherein antiprotons are provided free.
• Availability: Fermilab has discussed giving us approx. 1%
of the antiproton production rate (2.4x1010/day), though for
good reason this number can be increased.
• Deceleration and Extraction: Antiproton pulse intensities
between 109 and 1011 can be decelerated and extracted.
Robotic Accessibility
• The only feasible option for accessing Fermilab
antiprotons on the time and financial scale of this
Phase II award is to construct a robot that can carry
the torsion balance to a convenient extraction point
in an existing beam line.
• Robot fabrication is complete, though tinkering is
ongoing. Fabrication of magnets and other
ancilliary hardware is mostly complete, again with
ongoing tinkering taking place.
Antiproton Detection
• An important way to reduce costs is to measure
the antiproton trajectory, transverse size and
shape, and energy distribution with innovative and
inexpensive detectors.
• One of the effects of antiproton annihilation
against a nucleus is the occasional creation of
positron emitting isotope.
• In the case of fluorine, the annihilation against a
neutron generates fluorine-18, which has a half life
of 110 minutes.
• Exposing a Teflon cylinder (CF2) to antiprotons will
produce a fluorine-18 with roughly 16% efficiency.
• Once the cylinder is exposed, a local hospital PET
scanner will be used to measure the above
antiproton beam properties.