Re: Experiments At Super K

[Leigh Palmer <palmer@SFU.CA>]

At 8:28 PM -0500 1/1/01, Robert B Zannelli wrote:
> Dear List members:
>         I would like to give an account of some rather exciting results of
> detection of cosmic ray induced Neutrinos at the Super Kamiokande site,
> hereafter known as Super K.
[remainder omitted]

If this is a new result (it looks like it is) please post the LANL
archive URLs which are relevant. The only result of which I have heard
previously involves the *anisotropy* of the ratio of muon neutrinos to
electron neutrinos, there being relatively fewer muon neutrinos
incident from below the horizon than from above, after compensating
for solar neutrinos, of course. The interpretation of the older result
was the the neutrinos incident from below the horizon had originated
from atmospheric cosmic ray events the other side of Earth (in the
most extreme case) and that those neutrinos had travelled for a
considerably greater distance than neutrinos incident from above the
horizon. Hence the Earth-penetrating neutrinos had had a greater time
to undergo oscillations between neutrino types, and a deficiency in
muon neutrinos resulted. There was also speculation that the MSW
effect (in which passage through matter somehow catalyzes neutrino
oscillations) was important.

It is always helpful to us nonspecialists if you tell us the archive
reference. A search on "atmospher* neutrinos" yielded 34 papers in the
year 2000 alone, and 224 in all. While it is possible to eliminate
some of these by title alone, it is a great deal of trouble to search
through that many to find the one to which you could direct us. I did
look up the papers of Gerald L. Fitzpatrick. I am unable to read them,
but he does cite a single Kamiokande result (hep-ex/9810001) which is
the result I already knew about.

Leigh