2 research outputs found
Technical Design Report for the Upgrade of the ALICE Inner Tracking System
No full textALICE (A Large Ion Collider Experiment) is preparing a major upgrade of its experimental apparatus, planned for installation in the second long LHC shutdown (LS2) in the years 2018-2019. These plans are presented in the ALICE Upgrade Letter of Intent submitted to the LHCC in September 2012. A key element of the upgrade is the construction of a new, ultra-light, high-resolution Inner Tracking System based on monolithic pixel detectors. This Technical Design Report is an update of the Conceptual Design Report for the Upgrade of the ALICE Inner Tracking System, which was presented to the LHCC in September 2012. The primary focus of the ITS upgrade is on the improved performance for detection of heavy-flavour hadrons, and of thermal photons and low-mass di-electrons emitted by the QGP. The Conceptual Design Report demonstrated that it is possible to build a new silicon tracker with greatly improved features in terms of determination of the distance of closest approach to the primary vertex, tracking efficiency at low transverse momenta, and read-out rate capabilities. This document presents an update of R&D activities, with particular focus on the technical implementation of the main detector components, and detector and physics performance. The detector performance and physics studies are based on Monte Carlo simulations that include the transport of particles in a detailed model of the new detector
Pseudorapidity dependence of the anisotropic flow of charged particles in Pb-Pb collisions at TeV
No full textWe present measurements of the elliptic (), triangular () and quadrangular () anisotropic azimuthal flow over a wide range of pseudorapidities (). The measurements are performed with Pb-Pb collisions at TeV using the ALICE detector at the Large Hadron Collider (LHC). The flow harmonics are obtained using two- and four-particle correlations from nine different centrality intervals covering central to peripheral collisions. We find that the shape of is largely independent of centrality for the flow harmonics , however the higher harmonics fall off more steeply with increasing . We assess the validity of extended longitudinal scaling of by comparing to lower energy measurements, and find that the higher harmonic flow coefficients are proportional to the charged particle densities at larger pseudorapidities. Finally, we compare our measurements to both hydrodynamical and transport models, and find they both have challenges when it comes to describing our data.We present measurements of the elliptic ( v2 ), triangular ( v3 ) and quadrangular ( v4 ) anisotropic azimuthal flow over a wide range of pseudorapidities ( −3.5<η<5 ). The measurements are performed with Pb–Pb collisions at sNN=2.76 TeV using the ALICE detector at the Large Hadron Collider (LHC). The flow harmonics are obtained using two- and four-particle correlations from nine different centrality intervals covering central to peripheral collisions. We find that the shape of vn(η) is largely independent of centrality for the flow harmonics n=2–4 , however the higher harmonics fall off more steeply with increasing |η| . We assess the validity of extended longitudinal scaling of v2 by comparing to lower energy measurements, and find that the higher harmonic flow coefficients are proportional to the charged particle densities at larger pseudorapidities. Finally, we compare our measurements to both hydrodynamical and transport models, and find they both have challenges when it comes to describing our data.We present measurements of the elliptic (), triangular () and quadrangular () anisotropic azimuthal flow over a wide range of pseudorapidities (). The measurements are performed with Pb-Pb collisions at TeV using the ALICE detector at the Large Hadron Collider (LHC). The flow harmonics are obtained using two- and four-particle correlations from nine different centrality intervals covering central to peripheral collisions. We find that the shape of is largely independent of centrality for the flow harmonics , however the higher harmonics fall off more steeply with increasing . We assess the validity of extended longitudinal scaling of by comparing to lower energy measurements, and find that the higher harmonic flow coefficients are proportional to the charged particle densities at larger pseudorapidities. Finally, we compare our measurements to both hydrodynamical and transport models, and find they both have challenges when it comes to describing our data
