ALICE is the heavy-ion experiment at the CERN Large Hadron Collider. The experiment continuously took data during the first physics campaign of the machine from fall 2009 until early 2013, using proton and lead-ion beams. In this paper we describe the running environment and the data handling procedures, and discuss the performance of the ALICE detectors and analysis methods for various physics observables.

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Triple-differential cross sections have been measured as a function of product mass, total kinetic energy, and center-of-mass scattering angle in reactions induced by "'U on ' 0, Mg, "Al, "S, "Cl, Ca, Ca, and ""Zn targets at several bombarding energies between 4.6 and 7.5 MeV /nucleon. The analysis focuses on binary processes in which the product masses are substantially different from the target-projectile masses. These include the complete fusion followed by fission as well as quasifission processes in which large mass transfers occur on a short time scale. The relative contributions of these two components are estimated from the mass-angle correlations and analyzed within the extra and extra-extra push concepts. The time scale for mass transfer in quasifission reactions is derived from turning angles of the intermediate complex, and it is found that the mass drift toward symmetry shows the characteristics of an overdamped motion with a universal time constant independent of scattering system and bombarding energy. This is consistent with the one-body nuclear dissipation mechanism being responsible for the damping in the mass asymmetry degree of freedom. Also the average total kinetic energy of reaction products in quasifission is independent of temperature, supporting the one-body dissipation hypothesis.The elimination of background arising from, e.g. , target impurities and ternary processes, does, however, in practice require the determination of additional parameters. This is especially important in the present experiment where the contribution from the various target constituents of composite targets, such as ZnS and LiCl, can be separated on the basis of these additional parameters.The experimental arrangement consists of four large area (20&(30 cm ) position sensitive avalanche detectors, ' two of which are positioned side by side around the beam axis at a distance of -60 cm from the target, the remaining two being situated at larger angles on opposite sides of the beam axis at a distance of -35 cm. The detector arrangement is shown in Fig. 1. Both binary and ternary coincidences occurring in the four detectors within a resolving time of -SOO -700 ps are recorded. This arrangement allows for the detection of coincident binary products over an angular range of 6' -70 in the laboratory corresponding to 0, =18 -162 . The system is efficient for products spanning the entire mass range from the target to the projectile, and the complete range of fragment kinetic energies.An identical detector arrangement and method of analysis were employed in earlier experiments as described in more detail in Ref. 13. The c.m. angular resolution and the mass resolution were b, HFwHM=2 (FWHM denotes full width at half maximum) and 6 A = 5 u, respectively.In addition, three 7.5 em&7. 5 cm diam NaI detectors were placed at backward angles for the detection of y rays

The design, construction, and commissioning of the ALICE Time-Projection Chamber (TPC) is described. It is the main device for pattern recognition, tracking, and identification of charged particles in the ALICE experiment at the CERN LHC. The TPC is cylindrical in shape with a volume close to 90 m 3 and is operated in a 0.5 T solenoidal magnetic field parallel to its axis.In this paper we describe in detail the design considerations for this detector for operation in the extreme multiplicity environment of central Pb-Pb collisions at LHC energy. The implementation of the resulting requirements into hardware (field cage, readout chambers, electronics), infrastructure (gas and cooling system, laser-calibration system), and software led to many technical innovations which are described along with a presentation of all the major components of the detector, as currently realized. We also report on the performance achieved after completion of the first round of stand-alone calibration runs and demonstrate results close to those specified in the TPC Technical Design Report.

HADES is a versatile magnetic spectrometer aimed at studying dielectron production in pion, proton and heavy-ion induced collisions. Its main features include a ring imaging gas Cherenkov detector for electron-hadron discrimination, a tracking system consisting of a set of 6 superconducting coils producing a toroidal field and drift chambers and a multiplicity and electron trigger array for additional electron-hadron discrimination and event characterization. A two-stage trigger system enhances events containing electrons. The physics program is focused on the investigation of hadron properties in nuclei and in the hot and dense hadronic matter. The detector system is characterized by an 85 % azimuthal coverage over a polar angle interval from 18• to 85• , a single electron efficiency of 50 % and a vector meson mass resolution of 2.5 %. Identification of pions, kaons and protons is achieved combining time-of-flight and energy loss measurements over a large momentum range. This paper describes the main features and the performance of the detector system.