共查询到20条相似文献,搜索用时 312 毫秒
1.
The large hadron collider (LHC) under construction at CERN will deliver ion beams up to centre of mass energies of the order
of 5.5 TeV per nucleon, in case of lead. If compared to the available facilities for the study of nucleus-nucleus collisions
(SpS and RHIC), this represents a huge step forward in terms of both volume and energy density that can be attained in nuclear
interactions. ALICE (a large ion collider experiment) is the only detector specifically designed for the physics of nuclear
collisions at LHC, even though it can also study high cross-section processes occurring in proton-proton collisions. The main
goal of the experiment is to observe and study the phase transition from hadronic matter to deconfined partonic matter (quark
gluon plasma —QGP). ALICE is conceived as a general-purpose detector and will address most of the phenomena related to the
QGP formation at LHC energies: for this purpose, a large fraction of the hadrons, leptons and photons produced in each interaction
will be measured and identified. 相似文献
2.
This review of low-p
T proton-proton physics at low luminosity at the large hadron collider (LHC) should cover all LHC experiments, but in practice,
is mainly related to ALICE, for reasons which will be explained. However, the relevance to other LHC experiments is clear,
as low-pT. phenomena represent an important component of the background to their high-pT. phenomena which needs to be calibrated. The ALICE collaboration will study proton-proton collisions as part of their heavy-ion
programme, where most signals are relative to the proton-proton system. In addition, the ALICE detector’s unique acceptance
at low pT as well as its unique particle identification capability will make it possible to carry out a program of genuine proton-proton
physics complementary to those of other LHC experiments. 相似文献
3.
N. Bastid 《Physics of Atomic Nuclei》2008,71(9):1505-1513
ALICE, the dedicated heavy-ion experiment at the LHC, has also an important proton-proton physics program. The ALICE muon
spectrometer will be presented and the corresponding physics analysis will be reviewed. A particular emphasis will be placed
on heavy-flavor measurement.
(for the ALICE Collaboration)
The text was submitted by the author in English. 相似文献
4.
K. Gallmeister B. Kämpfer O.P. Pavlenko 《The European Physical Journal C - Particles and Fields》1999,8(3):473-478
In ultrarelativistic heavy-ion collisions at 20 (120) AGeV a copious production of charm (bottom) production sets in which, via correlated semileptonic () decays, gives rise to a dilepton yield at invariant mass 2–3 GeV in excess of the Drell-Yan yield and the thermal dilepton signal from deconfined matter as well. We show that appropriate
single-electron transverse momentum cuts (suitable for ALICE at LHC) cause a threshold like behavior of the dilepton spectra
from heavy-quark meson decays and the Drell-Yan process and can allow to observe a thermal dilepton signal from hot deconfined
matter.
Received: 28 September 1998 / Revised version: 27 November 1998 / Published online: 22 March 1999 相似文献
5.
M. Estienne 《Physics of Atomic Nuclei》2008,71(9):1535-1542
The observation of the strong suppression of high-p
t hadrons in heavy-ion collisions at the Relativistic Heavy Ion Collider (RHIC) at BNL has motivated a large experimental program
using hard probes to characterize the deconfined medium created. However, what can be denoted as “leading particle” physics
accessible at RHIC presents some limitations which motivate at higher energy the study of much more penetrating objects: jets.
The gain in center-of-mass energy expected at the Large Hadron Collider (LHC) at CERN will definitively improve our understanding
on how the energy is lost in the system, opening a major new window of study: the physics of jets on an event-by-event basis.
We will concentrate on the expected performance for jet reconstruction in ALICE using the EMCal calorimeter.
(for the ALICE Collaboration)
The text was submitted by the author in English. 相似文献
6.
A. Morsch 《The European Physical Journal C - Particles and Fields》2005,43(1-4):333-336
In central Pb-Pb collisions at the LHC, jet rates are expected to be high at energies at which ALICE can reconstruct jets
over the background of the underlying event. This will open the possibility to quantify the effect of partonic energy loss
through medium induced gluon radiation, jet quenching, by detailed measurement of the modification of the longitudinal and transverse structure of identified jets. In order to
obtain probes sensitive to the properties of the QCD medium, it is mandatory to measure the high-
parton fragments together with the low-
particles from the radiated gluons. Hence, the excellent charged particle tracking capabilities of ALICE combined with the
proposed electromagnetic calorimeter for ALICE, EMCAL, represent an ideal tool for jet quenching studies at the LHC.
Electronic Supplementary Material Supplementary material is available for this article at
PACS:
25.75.Nq, 24.85. + p, 13.87.-a 相似文献
7.
A. Marín 《The European Physical Journal C - Particles and Fields》2009,61(4):735-740
Heavy-ion collisions will enter a new era with the start of the CERN Large Hadron Collider (LHC). A first short run with proton-proton
collisions at the injection energy of 0.9 TeV will be followed by a longer one with pp collisions at 10 TeV. First Pb-Pb collisions at
TeV will take place in 2009. Three experiments (ALICE, ATLAS, and CMS) will study both pp and Pb-Pb collisions. A selection of results showing the capabilities of the three experiments for the study of the LHC medium
with direct photons is presented. 相似文献
8.
大型重离子对撞实验(A Large heavy-Ion Collision Experiment,ALICE)按计划在大型强子对撞机(Large Hadron Collider,LHC)的第二次停机(2019—2021)期间进行探测器升级工作。为了对强相互作用物质——夸克胶子等离子体(Quark-Gluon Plasma,QGP)的性质进行更细致的研究,作为升级计划中重要的一个内容是把ALICE实验现有的内径迹系统探测器(Inner Tracking System,ITS)全面升级为基于单片有源像素传感器(Monolithic Active Pixel Sensor,MAPS)技术的硅像素探测器(习惯称之为ITS2),并在Run 3和Run 4期间采集更多的铅核-铅核碰撞数据。新的ITS2共由7层(内3层,中间2层和外2层)探测桶面组成,共由24 000余片尺寸为3 cm × 1.5 cm的MAPS硅像素芯片(该芯片称之为ALPIDE)构成,有效探测面积达10 m2,共约120亿像素。ALPIDE芯片厚度为50 μm,单个像素的尺寸是27 μm × 29 μm,该芯片具有低功耗、高空间分辨率和高速读出等特点。ITS2将使ALICE探测器在测量极低横动量粒子时具备优异的探测效率和碰撞参数分辨率,同时也使ALICE探测器适应于LHC高束流亮度环境。目前ITS2的探测器模块量产和测试已于2019年完成,并在欧洲核子中心(CERN)洁净室完成了7层桶面的组装与安装,于2020年完成试运行测试。2021年1月启动ITS2在ALICE探测器中的安装与试运行工作,计划于2021年5月底完成ITS2的安装与测试。本工作将对ALICE/ITS2的探测器结构、ALPIDE芯片和升级进展等方面进行介绍。 相似文献
9.
The Large Hadron Collider (LHC) under construction at CERN is also planned as a heavy ion collider with lead ions colliding at an energy of 2.7+2.7 ATeV. This corresponds to collisions of matter with cosmic rays of the utmost energies observed so far promising the study of new and exciting aspects of physics. Minor improvements of the newly commissioned lead ion source at the CERN SPS are necessary in order to provide a luminosity of L=2×1027 cm?2s?1. The detector ALICE has been chosen as the third detector for the LHC and will be dedicated to the physics of these nuclear collisions and also to the large cross section physics in p+p collisions. 相似文献
10.
R. Vernet 《Physics of Atomic Nuclei》2008,71(9):1523-1534
The study of strangeness production at LHC will bring significant information on the bulk chemical properties, its dynamics,
and the hadronization mechanisms involved at these energies. The ALICE experiment will measure strange particles from topology
(secondary vertices) and from resonance decays over a wide range in transverse momentum and shed light on this new QCD regime.
These motivations will be presented as well as the identification performance of ALICE for strange hadrons.
(for the ALICE Collaboration)
The text was submitted by the author in English. 相似文献
11.
F. Noferini 《The European Physical Journal C - Particles and Fields》2007,52(1):247-251
The aim of this work is to extend to LHC the results observed for two-particle correlations at RHIC, especially in terms of
jet quenching effects. In this study a parton quenching model developed in the BDMPS-Z-SW framework is considered and implemented
as an afterburner for PYTHIA and HIJING. A simplified parametrization of the quenching mechanism at the parton level is included
in one of the most popular Monte Carlo event generators for AA collisions, HIJING. The simulation method, tuned on the RHIC
data, is then used to make predictions for the LHC energy regime in order to probe the scenario we will study in the ALICE
experiment. 相似文献
12.
B. G. Zakharov 《JETP Letters》2011,93(12):683-687
We perform a joint jet tomographic analysis of the data on the nuclear modification factor R
AA
from PHENIX at RHIC and ALICE at LHC. The computations are performed accounting for radiative and collisional parton energy
loss with running coupling constant. Our results show that the observed slow variation of R
AA
from RHIC to LHC indicates that the QCD coupling constant is suppressed in the quark-gluon plasma produced at LHC. 相似文献
13.
Y P Viyogi 《Pramana》2000,54(4):589-602
We describe the important results from the recent experiments using lead beams at the CERN SPS. The results of the WA98 experiment,
which has substantial Indian participation along with the photon multiplicity detector is described in some detail. Combining
the preliminary results from various experiments looking at different signals of phase transition, one finds enough evidences
to suggest that phase transition has taken place in nuclear collisions at the SPS. Future programme of heavy ion physics at
the LHC is being greared around the ALICE experiment. This will comprise of detector subsystems capable of studying almost
all the signals in the same event. The photon multiplicity detector will be an important component of the ALICE experiment,
being a totally Indian contribution to ALICE. 相似文献
14.
A study of energy behavior of the pion spectra and interferometry scales is carried out for the top SPS, RHIC and for LHC
energies within the hydrokinetic approach. The main mechanisms that lead to the paradoxical, at first sight, dependence of
the interferometry scales with an energy growth, in particular, a decrease R
out/R
side ratio, are exposed. The hydrokinetic predictions for the HBT radii at LHC energies are compared with the recent results of
the ALICE experiment. 相似文献
15.
Special features and parameters of detectors, front-end electronics, and trigger electronics of the ALICE setup, which is intended for investigations of ultrarelativistic nucleon-nucleon collisions at the LHC and for studies of heavy ion collisions, starting from protons to several types of ions, which have 5.5 TeV/nucleon energy in the center of mass, are described. One of the first collisions of lead ions was recorded by the ALICE detector on November 8, 2010. 相似文献
16.
The European Physical Journal C - The ALICE experiment at the CERN LHC will be dedicated to the investigation of heavy ion reactions at the highest energies. The main objective is the study of... 相似文献
17.
B. Hippolyte 《The European Physical Journal C - Particles and Fields》2007,49(1):121-124
Strange quark and hadron production will be studied at the large hadron collider (LHC) energies in order to explore the properties
of both pp and heavy-ion collisions. The ALICE experiment will be specifically efficient in the strange sector with the identification
of baryons and mesons over a wide range of transverse momentum. Dedicated measurements are proposed for investigating chemical
equilibration and bulk properties. Strange particles can also help to probe kinematical regions where hard processes and pQCD
dominate. We try to anticipate here several ALICE analyses to be performed as the first Pb–Pb and pp data will be available.
PACS 25.75.-q; 25.75.Dw 相似文献
18.
Simulation study on ω, ϕ, ρ decays to e
−
e
+ pairs in the ALICE detector for Pb-Pb collisions at LHC energy was performed. The possibility of selecting resonance signals
over the combinatorial backgrounds is demonstrated using the realistic simulation tracking and particle identification algorithms
of the ALICE offline framework (AliRoot). Results for J/ψ are presented also for comparison. 相似文献
19.
Physics of Atomic Nuclei - During the upcoming Run 3 and Run 4 at the LHC the upgraded ALICE (A Large Ion Collider Experiment) will operate at a significantly higher luminosity and will collect two... 相似文献
20.
F. Guérin 《The European Physical Journal C - Particles and Fields》2007,49(1):143-148
ALICE (A Large Ion Collider Experiment) is the LHC detector dedicated to the study of nucleus–nucleus collisions, in which
the formation of the quark–gluon plasma (QGP) is expected. Heavy quarkonia, especially the Upsilon states, are relevant for
studying the QGP since they provide an essential probe of the earliest and hottest stages of heavy ion collisions. They will
be measured via their dimuon decay channel in ALICE in the muon spectrometer. The muon spectrometer performance has been studied
in simulations, the results will be presented with emphasis on the trigger efficiency and rate in Pb–Pb collisions. The expected
yields of Upsilon states will be extracted from a simulation based on a global fit of the dimuon mass spectra for different
collision centralities. 相似文献