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Re: WIMP=big big neutrino?

I just checked the web site where there is an abstract of a
preprint about searching for WIMPS. "Search" means that they are not
really claiming detection. The experiment is at Gran Sasso where they
have a detector consisting of 100 kg of NaI. I'm not sure of the nature
of the signal, but whatever it is, they look for an annual variation.
They claim to see such a variation at the 4 sigma level (which is the
usual minimum for claiming an effect). The trouble is that it takes
about 300 years to identify an annual effect with a precision of one
day (that's an uncertainty principle calculation that most of you can
easily reproduce).
I don't think that this will get very far unless it is
substantiated from one of the other underground labs, all of which have
been aware of the search. I stated in an earlier post that an apparent
annual effect in the Soudan Mine was explained as radon contamination
chich is seasonal (because of changes in ventilation of the mine).
Regards,
Jack


Adam was by constitution and proclivity a scientist; I was the same, and
we loved to call ourselves by that great name...Our first memorable
scientific discovery was the law that water and like fluids run downhill,
not up.
Mark Twain, <Extract from Eve's Autobiography>

On Sat, 19 Feb 2000, Ludwik Kowalski wrote:

The front page of The New York Times reports today about
the announcement the Italian physicists will make at the meeting
on Dark Matter in California next Friday. WIMP stands for
the "weakly interacting massive particle" presumably found
through the "cumulative analysis of data collected over the
three year". There is a public web site about it but it did not
see it (www.lngs.infn.it).

They say that billions of WIMPs (each at least 50 times more
massive than a proton) pass our bodies each seconds but the
interaction cross sections are extremely small. The particles
were presumably discovered via scintillations in a sodium
iodine detector. Hard to believe, but who knows?
Ludwik Kowalski