Orateur
Natalia Di Marco
(L'Aquila University & INFN)
Description
The OPERA experiment aims at measuring the numu->nutau oscillation through the nutau appearance in an almost pure numu beam produced at CERN SPS, 730 Km far from the detector. The nutau appearance signal is detected through the measurement of the decay daughter particles of the tau lepton produced in CC nutau interaction.
Since the short-lived tau particle owns, at the energy of the beam, an average decay length of about 1 mm, a micrometric detection resolution is needed. For this purpose the OPERA detector placed in the hall ”C” of the Gran Sasso National Underground Laboratories, makes use of nuclear emulsions, the highest spatial resolution tracking detector, combined with lead plates in an emulsion cloud chamber structure (ECC). The ECCs are arranged in a compact structure called ”brick” and composed by 57 300-micron tick, emulsion films alternated with 56 1-micron tick, lead layers.
The target is made of 150 000 bricks for a total mass of 1.3 ktons. Electronic detectors complete the target section of the apparatus, while muon identification is performed by means of two magnetised spectrometers
The detector construction was fully equipped in summer 2008 and data taking started at the end of June 2008. In five years of data taking, the experiment is expected to collect about 10 to 15 nutau interactions while the estimated background is less than ~0.8 events.
In this talk, we will review the physics potential of the experiment, the performances of the detector and the first results obtained in the analysis of the 2008 run events.
Auteur principal
Natalia Di Marco
(L'Aquila University & INFN)
