Branching Intensity – the reference below is a dead link and the info comes
from a google cache.
www.fas.org/sgp/othergov/doe/lanl/docs1/00326396.pdf
"The fraction of decays that is accompanied by the emission of a specific
energy gamma ray is called the branching intensity… Uranium-235 decays by
alpha-particle emission with a half-life of 7 x 10^8 yr…. 54% of the alpha
particles are accompanied by a 185.7-keV gamma ray…
The gist of the situation for those performing gamma testing is that half of
alpha emissions can be accompanied by direct gamma radiation (at least for U,
but who knows what the actual ratio is for radon). I suspect the Branching
Intensity (BI) is higher for Rn than the 54% for U, since the alpha emission is
stronger for Rn.
Jones
-------------------------
Bob,
In addition to gamma rays from those two daughters you mentioned, one must also
include the branching intensity of radon itself.
Often with high energy alpha decay, as in radon – the alpha is accompanied by a
gamma ray which shares a fraction of the net energy released.
The branching intensity is the fraction of alpha decay that is accompanied by
the emission of a gamma. I do not have the exact number handy for radon, but if
memory serves it is relevant when the counts are this low.
From: Bob Higgins
I stand corrected. It appears that 214Bi and 214Pb are gamma emitters in the
radon daughter chain. Most of the signatures are between 100keV and 1MeV with
a few above.
Jones Beene wrote:
Bob,
All three radon isotopes have gamma decay channels in addition to alpha. The
signatures are well known (around 6 MeV).
Radon detection is a cottage industry in silicon valley
From: Bob Higgins
Jeff's setup may be more sensitive to radon than Alan's. The NaI detector that
Alan used is only sensitive to gamma, and not beta. Radon decay chains are
primarily alpha and beta emissions. With the foil wrapped around Jeff's GM
detector, he probably does not have much alpha sensitivity, but he will still
have beta sensitivity - which could come from radon. Beta and alpha
sensitivity can be evaluated with check sources. If Jeff is in the same area
as Alan, he could borrow Alan's check sources, but I am not sure if Alan has a
beta source. A good 24 hour background collection would also be useful as a
null test to look for radon caused variation.
On Sat, Mar 5, 2016 at 8:35 AM, Jones Beene <jone...@pacbell.net> wrote:
From: Jack Cole
Ø Jeff Morriss has just published a nice study showing radiation of 7x
background.
https://www.lenr-forum.com/forum/index.php/Thread/2847-Celani-Type-Replication/
This is nice. Here is one comment to file away as a possible mundane
explanation.
Jeff Morriss is in the same general geographic area as Alan Goldwater, and is
probably working in his garage. Radon gas is known to be high in Alan’s area,
and probably in Jeff’s also -- and 7x background is fully explainable by radon,
if it is there… as is the apparent half-life average.
… but wait, you say, Jeff did calibrate against background before seeing the
higher rate, and also the half-life of 222Rn is about 4 days, not one hour.
Yes, but this calibration would not eliminate the source being Radon, since he
is running a charged wire experiment - and when the experiment is turned on, it
would attract radon to the wire and thus concentrate the signal. Plus a factor
of 7 concentration is not unusual; plus the average of all three radon isotopes
can be in the one hour half-life range.
Therefore – the source of radiation could be radon. At least it has not yet
been ruled out.
One way to lessen radon is to move the experiment outside, or to an area of
lower radon emission (assuming it is high at Jeff’s location).
