AW: [ RadSafe ] Californium vs. Americium

[Franz Schönhofer]

Mike (and others interested),

Far from being an expert on neutron sources I remember that Cf-252 is used
as a single source of neutrons because of spontaneous fission - as you
pointed out. I never heard that its alpha-particles were used to generate
neutrons together with Be. 

Po/Be neutron-sources have been and are obviously still used in nuclear
reactors and in nuclear bombs. 

The first neutron-sources were obviously Ra-Be mixtures. I doubt they are
still used.

Using DU as a source for alpha-particles would - if it were possible - not
reduce the quantity of DU stored significantly.....

Best regards,

Franz

Franz Schoenhofer, PhD
MinRat i.R.
Habicherg. 31/7
A-1160 Wien/Vienna
AUSTRIA


-----Ursprüngliche Nachricht-----
Von: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] Im Auftrag
von Brennan, Mike (DOH)
Gesendet: Donnerstag, 28. Juni 2007 20:38
An: radsafe
Betreff: RE: [ RadSafe ] Californium vs. Americium

I admit to not knowing much about these kinds of neutron sources (in my
program, if you wanted to expose something to neutrons you ran it into
the reactor), but I was under the impression that the reason for using
CF was the SF neutrons.  My source says that CF-252 decays via SF about
11% of the time.  I have no idea of what percentage of the alpha decays
cause an "alpha + Be => n" reaction, but I suspect it is a function of
the energy of the alpha and the abundance of Be atoms to encounter.

I realize there are non-trivial drawbacks, but it is a shame that they
can't use some of the DU to make DUBE sources.  In addition to a cool
name, you could calibrate your logging equipment once, and you'd be good
to go for your lifetime.