II UCLEAR PHYSIC~ I11 PROCEEDINGS SUPPLEMENTS ELSEVIER Nuclear Physics B (Proc. Suppl.) 48 (1996) 183-187 The CHORUS experiment Presented by Daniela Macina for the CHORUS Collaboration: J. Konijn, R. G. C. Oldeman, C. A. F. J. van der Pod, J. W. E. Uiterwijk (NIKHEF, Amsterdam, The Netherlands) E. Eskut, G. Onengfit (~ukurova University, Adana, Turkey) E. Pesen, M. Serin-Zeyrek, R. Sever, P. Tolun, M. T. Zeyrek (METU, Ankara, Turkey) N. Armenise, F. Cassol, M. G. Catanesi, M. T. Muciaccia, S. Simone (INFN and University, Bari, Italy) K. HSpfner, T. Patzak (Humboldt University, Berlin, Germany) P. Annis, M. Gruw~, C. Mommaert, M. Van der Donckt, P. Vilain, G. Wilquet (Inter-University Institute for High Energies (ULB-VUB), Brussels, Belgium) C. H. Hahn ( Changwon National University, Changwon, Korea) J.Y. Kim (Chonnam National University, Chonnam, Korea) E. Di Capua, C. Luppi, S. Rieciardi, B. Saitta, P. Zucchelli (Universitd di Fewara and Istituto Nationale di Fisica Nucleare (INFN), Ferrara, Italy) J. Brunner, A. Capone, M. de Jong, J. P. Fabre, R. Ferreira, W. Flegel, J. Goldberg(Haifa), P. Gorbunov, R. Gurin, D. Macina, H. Meinhard, E. Niu, H. Over's, J. Panman, F. Riecardi, J. L. Visschers, Ch. Weinheimer, K. Winter, H. Wong ( CERN, Geneva, Switzerland) K. Nakazawa ( Gifu University, Gifu, Japan) H. Chikawa (Kinki University, Higashiosaka, Japan) E. Arik, I. Birol, A. A. Mailov (Bogazici University, Istanbul, Turkey) I. G. Park, J. S. Song (Gyeongsang National University, Jinju, Korea) K. Kodama, N. Ushida (Aichi University of Education, Kariya, Japan) S. Aoki, T. Haxa (Kobe University, Kobe, Japan) D. Favart, G. GrSgoire, G. Brooijmmas, J. HSrin, V. Lema~tre, L. Michel (Universitd Catholique de Louvain, Louvain-la-Neuve, Belgium) A. Artamonov, V. Khovansky, A. RoT.ahoy, V.Shamanov, V.Smirnitsky (Institute for Theoretical and Ezpevimental Physics, Moscow, Russian Federation) D. Bonekaemper, D. Frekers, D. Rondeshagen (MFmster University, M~nster, Germany) K. Hoshino, M. Kobayashi, M. Nakamura, Y. Nakamura, K.Nin, K. Niwa, T. Nakano, O. Sato (Nagoya University, Nagoya, Japan) S. Buontempo, A. Coeeo, A. Ereditato, G. Fiorillo, F. Garufi, F. Marehetti-Stasi, P. Migliozzi, V. Palladino, P. Strolin (Universitg~ and Istituto Nazionale di Fisica Nucleare (INFN), Naples, Italy) K. Nakamura, T. Okusawa, M. Teranaka (Osaka City University, Osaka, Japan) D. De Pedis, S. Di Liberto, U. Dote, P. F. Loverre, M. A. Mrm~.oni, A. Maslennikov, F. Meddi, G. Piredda, R. Santaeesaria (Universitd 'La Sapienza' and Istituto Nazionale di Fisica Nucleare (INFN), Rome, Italy) A. di Bartolomeo, G. Grella, G. Romano, G. Rosa (INFN and University, Salerno, Italy) S. Ogawa, H. Shibuya (Toho University, Funabashi, Japan) Y. Sato, I. Tezuka (Utsunomiya University, Utsunomiya, Japan) The Chorus experiment, which alms at a search for vt, ---" t~ oscillations using the neutrino beam of the CERN-SPS, has successfully taken data in 1994 and 1995. The detection technique will be discussed and the performances of the apparatus as well as a status report will be given. 1. INTRODUCTION The fundamental questions about neutrinos remain one of the most challenging questions of experimental high energy physics. Answers may come from searches of neutrino oscillations. Results from recent experiments on solar neu- trinos are consistent with a Mikheyev-Smirnov- 0920-5632/96/$15.00© 1996 ElsevierScienceB.V. All rights reserved. PII: S0920-5632(96)00234-4 Wolfenstein solution to the solar problem [1]. One of the favoured solutions gives a mass of ~ 3 meV to the v u and through the see-saw mech- anism a mass to the v~ (m~. ~ 10 eV) which would make it a candidate for dark matter [2]. Recent results on the anisotropy of the cosmic background radiation favour m~. ~ 7 eV. None of these considerations is compelling however, it