109357009
Data quality monitor as the final quality assurance procedure for the ALICE-TOF detector
All the steps which led to the construction of the ALICE-TOF detector were strictly followed by a set of quality assurance procedures to guarantee high and uniform performances. Once a module of the detector (whose basic element is the Multigap Resistive Plate Chamber) is assembled, a final test concerning the data readout applies. While the detector is taking data, both during test and physics runs, a check of the quality of the data is needed. For this purpose some monitoring tools have been developed. These tools have been used since the beginning of the TOF commissioning and finally they have also been successfully used during the first global data-taking test-runs of ALICE.
121872628
The ALICE Time-Of-Flight detector: status and expected performance at the LHC startup
A. Akindinova, A. Alicib,c, P. Antoniolic, S. Arcellib,c, M. Basileb,c, G. Cara Romeoc, L. Cifarellib,c, F. Cindoloc, A. De Carod, D. De Gruttolad, S. De Pasqualed, M. Fusco Girardd, B. Guerzonib,c, D. Hatzifotiadouc, H.T. Junge, W.W. Junge, D.S. Kime, D.W. Kime, H.N. Kime, J.S. Kime, S. Kiseleva, G. Laurentic, K. Leee, S.C. Leee, D. Malkevicha, A. Margottic, R. Naniac, A. Nedosekina, F. Noferinic,g , P. Paganod, A. Pescic, O. Pinazzac, R. Preghenellac,f,∗, M. Ryabinina, E. Scapparonec, G. Sciolib,c, A. Silenzib,c, M. Tchoumakova, K. Voloshina, M.C.S. Williamsc, B. Zagreeva, C. Zampollig,h, A. Zichichib,c,f . a Institute for Theoretical and Experimental Physics, Moscow, Russia b Dipartimento di Fisica dell’Universita, Bologna, Italy c Sezione INFN, Bologna, Italy d Dipartimento di Fisica dell’Universita and INFN, Salerno, Italy e Department of Physics, Kangnung National University, Republic of Korea f Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, Rome, Italy g INFN–CNAF, Bologna, Italy h CERN, Geneva, Switzerland
124469673
The ALICE Time-Of-Flight system: Construction, assembly and quality tests
16382276
Multiplicity studies and effective energy in ALICE at the LHC
In this work we explore the possibility to perform “effective energy” studies in very high energy collisions at the CERN large hadron collider (LHC). In particular, we focus on the possibility to measure in pp collisions the average charged multiplicity as a function of the effective energy with the ALICE experiment, using its capability to measure the energy of the leading baryons with the zero degree calorimeters. Analyses of this kind have been done at lower centre-of-mass energies and have shown that, once the appropriate kinematic variables are chosen, particle production is characterized by universal properties: no matter the nature of the interacting particles, the final states have identical features. Assuming that this universality picture can be extended to ion–ion collisions, as suggested by recent results from RHIC experiments, a novel approach based on the scaling hypothesis for limiting fragmentation has been used to derive the expected charged event multiplicity in AA interactions at LHC. This leads to scenarios where the multiplicity is significantly lower compared to most of the predictions from the models currently used to describe high energy AA collisions. A mean charged multiplicity of about 1000–2000 per rapidity unit (at η∼0) is expected for the most central Pb–Pb collisions at $\sqrt{s_{{\text{NN}}}} = 5.5\,\text{TeV}$.
108880980
A topological trigger based on the Time-of-Flight detector for the ALICE experiment
The goal of the ALICE Time-of-Flight detector, based on MRPC technology, is to perform the charged-particle identification at midrapidity, in the region |η| < 0.9. This large area (∼150 m 2 ), finely segmented detector (∼157,000 channels), provides fast signals which will contribute to the Level 0 and Level 1 trigger decisions. We use the TOF detector information to perform an online estimate of the total track multiplicity and to identify simple and peculiar topologies, like those produced by minimum bias p-p, Ultra Peripheral ion-ion collisions and cosmic muons. The system architecture foresees a first layer of 72 VME boards interfacing the detector front-end to a second layer, which receives and processes all the information and takes trigger decisions.
120503228
Construction and tests of the MRPC detectors for TOF in ALICE
Abstract CERN-LHC (Large Hadron Collider) accelerator facility will provide heavy ions (Pb–Pb) collisions with a center-of-mass (CM) energy of about 5.5 TeV per nucleon pair. In the extreme conditions of temperature and energy density created in such collisions, a transition from hadronic matter towards a deconfined state of quarks and gluons is predicted by Quantum Chromodynamics (QCD) calculations on the lattice. The Time Of Flight (TOF) detector system of the ALICE (A Large Ion Collider Experiment) apparatus, is presently progressing in the assembling process at LHC at CERN. The TOF, in combination with the other central tracking detectors of ALICE provides an excellent Particle IDentification (PID) in the momentum range 0.2 – 2.5 GeV / c for K / π and up to 4 GeV/ c for K/p. The ALICE TOF is a barrel detector consisting of double-stack Multigap Resistive Plate Chamber (MRPC) strips, equipped with readout pads. The MRPC is characterized by an intrinsic time resolution below 50 ps and an efficiency over 99%. The assembling procedures, the tests of mechanics, cooling system and electronics of the 8 m long TOF “supermodules”, together with the performance tests before installation in the experimental area, will be presented.
125063915
Experimental study of resonant states in P-27 via elastic scattering of Si-26 + p
120873348
Installation and commissioning of EURICA – Euroball-RIKEN Cluster Array
Abstract EURICA is a project at RIKEN Nishina Center aimed at studying a wide range of exotic nuclei through β -decay measurements and high-resolution γ -ray spectroscopy. The setup is located behind the BigRIPS fragment separator and the ZeroDegree spectrometer at the RIBF. EURICA consists of the HPGe cluster detectors from the previous Euroball and RISING projects, together with double-sided silicon-strip detectors for β -decay counting and lifetime measurements. In total, this setup provides us with the possibility to study several aspects of the exotic nuclei produced at the RIBF.
120011305
β-decay spectroscopy at RIBF: The EURICA project
EURICA is a project at the RIKEN Nishina Center aimed at studying a wide range of exotic nuclei through β-decay measurements and high-resolution γ-ray spectroscopy. During its first two years of operation, about 80 days of beam time have been dedicated to the project allowing the exploration of several very exotic regions of the nuclear chart, which include key nuclei such as 78Ni, 100Sn, 110Zr, 128Pd, and 138Sn. Data analysis of the EURICA experiments is currently ongoing.
117824458
A confirmative spin-parity assignment for the key 6.15 MeV state in $^{18}$Ne of astrophysical importance
Proton resonant states in $^{18}$Ne have been investigated by the resonant elastic scattering of $^{17}$F+$p$. The $^{17}$F beam was separated by the CNS radioactive ion beam separator (CRIB), and bombarded a thick H$_2$ gas target at 3.6 MeV/nucleon. The recoiled light particles were measured by using three sets of ${\Delta}$E-E Si telescope at scattering angles of $\theta$$_{lab}$$\approx 3^\circ$, 10$^\circ$ and 18$^\circ$, respectively. Four resonances, {\it i.e.}, at $E_{x}$=6.15, 6.30, 6.85, and 7.05 MeV, were observed clearly. By $R$-matrix analysis of the excitation functions, $J^{\pi}$=1$^-$ was firmly assigned to the 6.15 MeV state which is a key state in calculating the reaction rate of $^{14}$O($\alpha$,$p$)$^{17}$F reaction. This reaction was thought to be one of the most probable key reactions for the breakout from the hot-CNO cycle to the $rp$-process in type I x-ray bursts In addition, a new excited state observed at $E_{x}$=6.85 MeV was tentatively assigned as 0$^{-}$, which could be the analog state of 6.880 MeV, 0$^{-}$ in mirror $^{18}$O.
131106858
Isomer and beta decay spectroscopy in the 132Sn region with EURICA
A. Jungclaus et al.; 4 pags.; 1 fig.; Open Access funded by Creative Commons Atribution Licence 2.0