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RE: Earth georeactor - recent publications
Dale,
I think you're right that neutrinos from the beta decay of the neutron are
not an issue, because there aren't any D-D reactions in the sun.
In his seminal book "Principles of Stellar Evolution and Nucleosynthesis,"
Donald Clayton writes concerning p-p fusion that the weak nuclear
interaction is so exceedingly rare, that the deuterium (D) that has been
formed never actually encounters another D.
As Clayton explains, "after the deuterium has been formed [in the p-p
fusion], one could imagine that He-4 might be produced by the reaction D +
D --> He-4 + ?. This reaction, however, suffers from..... the fact that the
deuterium abundance is kept very small by its interaction with protons [in
the reaction D + p --> He-3 + ?, following which the helium nuclei fuse
according to He-3 + He-3 --> He-4 + p + p ].
.....That these are the major reactions comes about because..... D can build
up only to a very small abundance." [ie. two Ds never bump into each other
in the sea of protons....]
According to
http://www.shef.ac.uk/uni/academic/N-Q/phys/people/vdhillon/teaching/phy213/
phy213_fusion3.html , "This [p-p] reaction occurs via the weak nuclear force
and the average proton in the Sun will undergo such a reaction approximately
once in the lifetime of the Sun, i.e. once every 10 billion years" (the
sun's life) ...this in spite of the fact that the protons undergo
approximately 10 billion collisions per second with other protons in the
solar interior.
Additional reference :
http://www2.slac.stanford.edu/vvc/theory/weakinteract.html
Beta Decay: The First Known Weak Interaction
The weak interaction was first recognized in cataloging the types of nuclear
radioactive decay chains, as alpha, beta, and gamma. decays. Alpha and gamma
decays can be understood in terms of other known interactions (residual
strong and electromagnetic, respectively). But, to explain beta decay
required the introduction of an additional rare type of interaction --
called the weak interaction.
Beta decay is a process in which a neutron (two down quarks and one up)
disappears and is replaced by a proton (two up quarks and one down), an
electron, and an anti-electron neutrino. According to the Standard Model, a
down quark disappears in this process and an up quark and a virtual W boson
is produced.. The W boson then decays to produce an electron and an
anti-electron type neutrino.
I can't answer your second question properly right now, since I'm not that
familiar with neutrino detectors (scintillators).
But the articles I've seen so far - including the ones I referenced in the
initial posting - don't seem too concerned about the solar neutrino
background.
Part of it is no doubt because the detectors used are directional (ie.
neutrinos coming from above can be discounted) and part of it seems to be
taken into account with the typical statement, "The signal can be tagged by
the signal produced after several tens of microseconds by the thermalised
neutron captured by hydrogen in the aromatic organic liquid scintillator.
The delayed coincidences suppress background enormously and the chance
coincidence rate in a kiloton scintillator mass detector such as installed
at Kamioka, Japan, can be limited to several events/year (Rhagavan, 2002)."
It is this thermalised neutron capture by hydrogen which also allows the
detector to be directional, since " The initial neutron direction vector is
kinematically correlated to the neutrino vector. Despite the thermalization
and diffusion of the neutron, the e+-n spatial displacement vector still
retains the memory of the original neutron direction, thus also the incident
neutrino vector. This major result was demonstrated in a practical liquid
scintillation detector recently in the CHOOZE experiment5 which observed the
`ne spectrum from a 3GW reactor ~1km away. They showed that the data could
point to the known direction of the reactor within a cone of half-angle of
18°. [...] Thus in principle, with reasonably good signal/background and
signal rates, `ne signals from surface power reactors and geo-U.Th could be
unscrambled from those of a georeactor in the center of the earth by their
orthogonal directions of origin even in a liquid scintillation detector."
(Rhagavan, 2002)
Hope this helps -- perhaps someone more knowledgeable can fill us in in
greater detail ?
Jaro
http://www.cns-snc.ca/branches/quebec/quebec.html
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-----Original Message-----
From: owner-radsafe@list.vanderbilt.edu
[mailto:owner-radsafe@list.vanderbilt.edu]On Behalf Of daleboyce@charter.net
Sent: Thursday, April 15, 2004 3:10 PM
To: Franta, Jaroslav; Radsafe (E-mail)
Subject: Re: Earth georeactor - recent publications
Franta,
It's an interesting article. My first reaction was to wonder how they sort
the georeactor signal out from the solar flux. Most of the solar flux is
neutrinos instead of antineutrinos. Since the main fusion cycle in the sun
doesn't generate any neutrons, the products tend to be neutron deficient. I
don't have a ready reference, but I would expect there to be some component
that does generate neutrons. For example D + D -> He3 + n. The neutrino
from the beta decay of the neutron wouldn't be energetic enough to produce a
positron though. However it could be captured to form an isotope that does
have a high enough decay energy. The rate should be small compared to the
neutrino flux, so it may not be an issue.
My other question would be how are they differentiating positrons from
negatrons? It doesn't say anything about looking for the annihilation
gamma-rays, and a positron looks a lot like a negatron in a scintillation
counter.
All this may be well thought through, but it would be interesting to know
how they are making the differentiation. Ray Davis got a piece of the Nobel
Prize in physics in 2002 for his solar neutrino work that began in 1964.
For years his results that the solar neutrino flux was a factor of 3 lower
than predicted were looked upon as flawed, but he kept up the battle and was
vindicated. The electron neutrino flux was low due to oscillations of
electron neutrinos into other flavors of neutrino, and their energy was too
low to create the inverse reaction into their respective lepton.
If the georeactor detector has a background due to solar neutrinos then
picking the signal out of the background could be difficult. That's an
understatement since the experiment is very difficult to begin.
Now off to dust off the old E&M book to see if 3TW is enough to generate the
earth's magnetic field. Small field but big magnet. Thanks for the post.
It's something to play with for a bit.
Does anyone know more about these experiments?
Dale
----- Original Message -----
From: Franta, Jaroslav
To: Multiple (E-mail) ; Radsafe (E-mail) ; ANS listserv (E-mail)
Sent: Thursday, April 15, 2004 7:17 AM
Subject: Earth georeactor - recent publications
A couple of publications from Russia's RAS and the Kurchatov Institute, and
one from the Netherlands, are available in pdf format on Marvin Herndon's
web site, nuclearplanet.com
G. Domogatski, V. Kopeikin, L. Milaelyan and V. Sinev, "Neutrino Geophysics
at Baksan I: Possible Detection of Georeactor Antineutrinos" arXiv.org
(January 28, 2004).
http://www.nuclearplanet.com/Neutrino%20Geophysics%20at%20Baksan%20I.pdf
And also arXiv.org (March 17, 2004).
http://www.nuclearplanet.com/0403155.pdf
R. J. de Meijer, E. R. van der Graaf and K. P. Jungmann, "Quest for a
Nuclear Georeactor", arXiv.org (April 8, 2004).
http://www.nuclearplanet.com/0404046.pdf
It appears that interest in this is building world-wide.
Exciting times !
Jaro
http://www.cns-snc.ca/branches/quebec/quebec.html
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