Last Update: October 2000 |
MONOLITH-RD
Collaboration
Berlin, Bonn, Hamburg, Muenster, Bologna, LNF, LNGS, Milano,
Napoli, Torino,INR (Moscow), MEPhI
(Moscow), Frescati (Stockholm), Columbia University
Laboratory and beam:
Laboratori Nazionali del Gran Sasso and atmospheric neutrino beam
1. Goal of the experiment
MONOLITH is a proposed experiment on atmospheric neutrinos at the
Gran Sasso laboratory in Italy. The detector would consist in a
massive (34 kt) magnetized tracking calorimeter, optimized for
the detection of atmospheric muon neutrinos. The main goal is to
establish (or reject) the neutrino oscillation hypothesis through
an explicit observation of the full first oscillation swing.
Oscillations will be discriminated against alternative hypothesis
like decay or decoherence The sensitivity range for this
measurement comfortably covers the full Dm2 (square of the mass
difference of the two neutrinos involved in the oscillation)
region allowed by the Super-Kamiokande experiment. Other
measurements include studies of matter effects, the neutral
currents up/down ratio, the neutrino/antineutrino ratio, the
study of cosmic ray muons in the multi-TeV range, and auxiliary
measurements from the CERN to Gran Sasso neutrino beam. Depending
on approval, data taking with part of the detector could start
towards the end of 2004.
2. Physics achievements during 2000
In the year 2000 the principles of the MONOLITH experiment have
been proven. It was shown that a detector with the proposed
design will be able to observe the first oscillation period and
discriminate the oscillation from alternative hypothesis: decay
or decoherence. The time resolution of the proposed detector
components (glass RPCs) was also measured in a dedicated run; it
was shown that the resulting up/down discrimination is sufficient
to reduce the cosmic ray background to a negligible level. The
proof of the principles and the demonstration of the existence of
a suitable technique led the collaboration to submit an
Experiment Proposal to the Scientific Committee of the LNGS.
3. INFN contribution to the experiment in
terms of manpower and financial support
- 9 full-time equivalent physicists and 5 technicians from INFN
groups were involved in MONOLITH R&D in the year 2000.
- In the year 2000 MONOLITH was funded by INFN as R&D. Total
financial support was 330 MLit
4. Number of publications in refereed
journals: 0
5. Number of talks to conferences: 5
6. Number of undergraduate and doctoral
thesis on the experiment:
- n.1 Ph.D.;
- n.4 graduates (Laurea thesis)
7. Leadership of the experiment
The spokesman of the experiment is Stefano Ragazzi of the Milano
group. Four out of five members of the Executive Committee are
from Italian INFN groups.
8. Innovative instruments:
In the R&D phase the collaboration is developing glass RPCs.
Glass RPCs cannot withstand a high particle rate per unit
area,but in a low rate environment as a cosmic ray
experiment- they represent a very promising detector technique:
high space resolution, down to 1 mm, depending on read-out pitch,
time response better than 1 ns, and low cost per unit
area(MONOLITH aims to large-scale industrial production at a cost
around 200 kLit, 100 $, per square meter).
9.Competing experiments
Competing experiments are Super-Kamiokande in Japan, running
since 1996, and MINOS on the NUMI long baseline neutrino beam
from Fermilab, which is foreseen to start data taking in fall
2003. Concerning the main goal of MONOLITH detection of the
oscillation pattern- Super-Kamiokande is most likely limited by
resolution, while MINOS will not cover the lower Dm2 values allowed by
Super-Kamiokande.
10.International committee that has
reviewed the experiment
The experiment proposal has been submitted and reported to the
Scientific Committee of Laboratori Nazionali del Gran Sasso
(LNGS).