AAWSAP DIRD, Positron Aerospace Propulsion, March 2010

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Table 5, the required 150 µg for this epic flight could be manufactured in 6 months for
$96 million, or 0.0007 percent of U.S. GDP.
Positron Storage
Confinement of antimatter has been reviewed extensively in the literature. 64
Historically, the first approach was the Penning trap. 65 Stores of 109 positrons for 1
hour have been achieved .66 Electric potentials are required to overcome space charge
forces. 67 To illustrate, confinement of 1015 positrons in a 10-cm-radius sphere in a
perfect vacuum requires an electric potential of 240 kilovolts. Laboratory control of such
large potentials restricts stores to < 1 picogram (10 15 ) .
Figure 19. Penning Trap With Trapping Volume of 1,000 Cubic Centimeters (center), Injection
Apparatus (left) and Controls (right) (courtesy Positronics Research LLC) 68
In addition, with a magnetic field there are magnetic energy density restrictions on
confinement of positron plasmas. The Brillouin Density Limit is:
2
n =EB /2m
(1)
B
o
e.
For a practical magnetic field of 1 Tesla, ns = 9.7 x 1012/cubic centimeters. In a 10-cm
rad ius sphere, the Brillouin Number Limit is 4 x 1016 (40 picograms). Therefore, by
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