Last Update: October 2000

THE CHORUS EXPERIMENT at the CERN SPS

1. Goal of the experiment

The main goal of The CHORUS experiment is the detection of possible

Oscillations of muon neutrinos to tau neutrinos via the detection

of neutrino tau interactions in a neutrino tau free beam (Wbb neutrino

beam at the CERN SPS). Chorus is an appearance experiment based on

the observation of tau decays in nuclear emulsions.

2. Physics achievements during the year 2000

The phase 2 of the experiment has started. This phase will be based on

the complete study of the interaction region. This will allow a better

efficiency in the detection of tau neutrino interactions and a study of

charm particles physics with unprecedented statistics.

Final results on the phase 1 search have been obtained.A limit of

6.3 10-4 on the nu mu nu tau mixing between has been reached.

3. INFN contribution to the experiment in terms of manpower and financial

support

* Manpower: INFN contributes with 6 Sections: Bari(6 physicts, 5.5 phe)

Cagliari (3 ,2.3),Ferrara (1, 1. ),Napoli (12, 10.5),Roma(7, 6.3),

Salerno(5, 3.)

* INFN financial support: 896 ML for year 2000

4. Number of publications in refereed journals:

* New results on neutrino mu to neutrino tau and neutrino e

oscillation. Physics letters in press

5. Number of talks to conferences (1999-2000)from INFN): 9

* P Righini: Electroweak Physics Lake Louise (Canada)

* M. Messina: Rencontres de Moriond on Electroweak Int.

and Unified Theories Les Arcs (France)

* E. Radicioni: Neutrino and Astroparticle Physics

San Miniato, Florence (Italy)

* S. Buontempo: Int. Conf. on Calorimetry in HEP (CALOR99)

* D'Ambrosio: Int Conf. on Position Sensitive Detectors

University College, London

* A. Satta: Results and perspectives in Part. Physics

La Thuile, Aosta (Italy)

* G De Lellis: Rencontres de Moriond, Electroweak Physics

Les Arcs (France)

* S. Ricciardi: Intersections in Particle and Nuclear Physics

(CIPANP2000), Quebec City (Canada)

* L. Ludovici: Neutrino 2000 Sadbury Canada

6. Number of undergraduate thesis on the experiment :5

Number of doctoral thesis on the experiment :6

7. Leadership role in the experiment:

* P.Strolin Spoke person of the experiment

8. Innovative Instruments:

Development of authomatic systems for emulsion measurements

9. Competing experiments:

Nomad experiment same physics goal as CHORUS at the same beam

but with a different technique.

10. International committees which have reviewed the experiment:

the SPSC committee at CERN.