NA61/SHINE

NA61/SHINE experiment logo

NA61/SHINE (SHINE = SPS Heavy Ion and Neutrino Experiment) is a particle physics experiment at the Super Proton Synchrotron (SPS) at the European Organization for Nuclear Research (CERN).^[1] The experiment studies the hadronic final states produced in interactions of various beam particles (pions, protons and carbon, sulfur, and indium nuclei) with a variety of fixed nuclear targets at the SPS energies.

About 120 physicists from 14 countries and 24 institutions work in NA61/SHINE, led by Marek Gazdzicki. Until the start of the LHC experiments, NA61/SHINE was the second largest experiment at CERN taking data.

Physics program

The NA61/SHINE physics program has been designed to measure hadron production in three different types of collisions:^[1]

• In nucleus–nucleus (heavy ion) collisions, in particular the measurement of fluctuations and long range correlations, with the aim to identify the properties of the onset of deconfinement and find evidence for the critical point of strongly interacting matter.
• In proton–proton and proton–nucleus interactions needed as reference data for better understanding of nucleus–nucleus reactions; in particular with regards to correlations, fluctuations and high transverse momenta.
• In hadron–nucleus interactions needed for neutrino (T2K) and cosmic-ray experiments (Pierre Auger Observatory and KASCADE).

Detector

NA61/SHINE detector layout

The NA61/SHINE experiment uses a large acceptance hadron spectrometer located on the H2 beam line in the North Area of CERN.^[1] The basic components of the current detector were constructed and used by the heavy ion NA49 experiment.^[2]

The main tracking devices are four large volume time projection chambers (TPCs), which are capable of detecting up to 70% of all charged particles created in the studied reactions. Two of them, the vertex TPCs, are located in the magnetic field of two super-conducting dipole magnets with maximum bending powers of 9 Tesla meters. Two others (MTPC-L and MTPC-R) are positioned downstream of the magnets symmetrically with respect to the beam line. One additional small TPC, the gap TPC, is installed on the beam axis between the vertex TPCs. The setup is supplemented by time of flight detector arrays, two of which were inherited from NA49 and can provide a time measurement resolution of about 60 ps.

In 2007, pilot run data for the T2K neutrino experiment on p+C interactions at 31 GeV/c were recorded. For this run a new forward time of flight detector was constructed in order to extend in these low-multiplicity events the acceptance for pion and kaon identification to low momenta (1 < p < 4 GeV/c). The forward time of flight detector is installed downstream of MTPC-L and MTPC-R, closing the gap between the other time of flight detectors. Furthermore, one super-module of the Projectile Spectator Detector (a calorimeter) was installed downstream of this time of flight detector.

A major step forward in the detector performance, the TPC readout and data acquisition upgrade, was achieved for the 2008 run. During the run the upgrade was tested and resulted in an increase of the data rate by a factor of about 10 compared to the NA49 rate. The 2008 run was cut short due to the 19 September 2008 LHC incident.

See also

• List of Super Proton Synchrotron experiments

References

1. ^ ^{a b c} Antoniou, N. et al.; (NA61 Collaboration) (2006). "Study of hadron production in hadron–nucleus and nucleus–nucleus collisions at the CERN SPS". SPSC-P-330, CERN-SPSC-2006-034. http://cdsweb.cern.ch/record/995681?ln=en. 
2. ^ Afanasiev, S. et al.; (NA49 Collaboration) (1999). "The NA49 large acceptance hadron detector". Nuclear Instruments and Methods in Physics Research A 430 (2–3): 210. Bibcode 1999NIMPA.430..210A. doi:10.1016/S0168-9002(99)00239-9. 

External links

• NA61/SHINE Collaboration web-site
• NA61/SHINE proposal
• NA49 Collaboration web-site