On May 5th we had a neutrino day in Uppsala.

1) First D. Kielczewska from
Warsaw and Univ. of California, who is a member of the Superkamiokande and K2K
Collaborations, gave an extensive lecture on recent results on neutrino
oscillations, especially from underground detectors. The results included
both atmospheric and solar neutrinos. We shall try to scan in her
transparenciesto make them publicly available.

2) C.P. de los Heros talked about the status and future of AMANDA.

3) T.Ekeloef presented an idea (with T.Ypsilantis and R. Forty)
of a tau neutrino appearance detector potentially
suited for the (second generation ?) of the long-baseline neutrino experiments.
It relies on the direct identification of the tau leptons produced in
charge-current interactions, by imaging the Cherenkov light that the tau
generates in the C_{6}F_{14} liquid. In a simple simulation about half
of the tau leptons can be successfully identified that way.
More about that detector can be found in JHEP 12 (1999) 002.

4) B. Badelek reviewed ICANOE and OPERA, the two planned CERN LBL experiments.
The difference between squared neutrino masses, \Delta m^2 is proportional
to the neutrino beam energy, E and inversely proportional to the
source-detector distance, L. Thus a sensitive experiment should have
a large L and small E. There are now
3 such setups planned in the world: K2K, Japan (L=250 km, E=1.5 GeV,
already started to take data), NUMI, USA (L=732 km, E=16 GeV (? depends on
the configuration), start in 2002)
and NGS ("Neutrinos to Gran Sasso", L=732, E=17 GeV, start in 2005).
The CERN neutrino beam has been approved in Dec. 1999 and will start operation
in 2005. At the Grans Sasso lab, which already points towards CERN, the
muon background will be reduced to about 1/m^2/hour.

ICANOE
======

The detector merges liquid argon imaging of ICARUS with NOE fine grain
calorimeter, upgraded for magnetic analysis of the muon. Measurement
and identification of final state electrons, photons, muons and hadron jets
will be possible. Layout is supermodule: events reconstructed with a quality
of a bubble-chamber (liquid target), complemented by an external identifier
(solid target). One supermodule (1 liquid + 1 solid target) is about
1.4 + 0.8 = 2.2 kton active mass. 4 supermodules are planned -> 8.8 kton.

The goal is to observe directly the oscillation mechanism and to measure
the full mixing matrix and mass differences. Atmospheric and NGS neutrinos
will be studied simultaneously, the latter in direct tau and electron
appearance and in muon disappearance. Nucleon decays will also be searched for.
Expected number of \nu_{\mu} CC events is 2450/kton/year
(admixture of other CC events is below 2%). CC events with \tau production
and decay (or electron production) will define a signature; background will be
rejected through kinematics and direct observation of a (\tau) decay topology.
For \Delta m^2 ~ 3.5 *10^{-3} eV^2, about 30 events/kton/year are predicted
for the tau appearance.
ICANOE will be much more precise in determination of \Delta m^2 than the
SuperKamiokande and and more sensitive to sin^2(2\theta) than MINOS.
Tests of the LiAr imaging are going on on the 600 ton module. They will be
completed by end of 2000; if successful the proposal (which is ready)
will be formally submitted to the SPSC (SPSC has already started to review
ICANOE).

More on ICANOE: their proposal (to be found on their home page). Recommended
is Andre Rubbia's talk on the Cracow EPIPHANY200 conference (transparencies
on the home page).

OPERA
=====

This is a \nu_\mu -> \nu_\tau appearance experiment, designed to measure
just that oscillation channel (possible extension to the \nu_\mu -> \nu_e
is investigated). Will employ a lead/emulsion target (segmented in
bricks-> modules -> supermodules) to detect tau
(through its decays) and electrons from the CC interactions. The bricks
will be dismounted/scanned/mounted back "on line" (serious technical problems!)
Emulsions, supplied by a Japanese company,
will be read out by compurt controlled CCD cameras. The total target mass
(mostly Pb) is about 800 tons. Expected number of events after 4 years running
will be 10 - 100 depending on the \Delta m^2 value.

More on OPERA: their proposal, especially CERN/SPS 98-25, to be found on their
home page.

Both experiments
================
are open to new members; needed are contributions in detector elements and
simulations. No finantial or engagement "thresholds" are defined.
 

5) To further structure our neutrino interests the "Neutrino Sverige" home
page has been created (www3.tsl.uu.se/~damet/neutrino.html) where all the current information,
links etc will be put. Special news will still be distributed by e-mail.
Everybody is kindly asked to respond whether she/he wishes to continue
receiving these mails. NO ANSWER BY JUNE 1 WILL BE UNDERSTOOD AS RESIGNATION
from participation in the information network.
 

Thank you very much.
With kind regards,

Barbara Badelek
Jerome Damet

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