scholarly journals OPEN CHARM ANALYSIS ON THE FIRST PP COLLISIONS AT $\sqrt{s} = 7~{\rm TeV}$ WITH ALICE

2011 ◽  
Vol 02 ◽  
pp. 25-30 ◽  
Author(s):  
◽  
GIACOMO ORTONA
Keyword(s):  
Production Cross ◽  
Hadron Collider ◽  
Heavy Ion ◽  
Nucleon Nucleon ◽  
Relativistic Heavy Ion Collisions ◽  
Alice Experiment ◽  
Proton Proton ◽  
Ion Collisions ◽  
Density State ◽  
Energy Domain

A Large Ion Collider Experiment (ALICE) is one of the four large experiments at the Large Hadron Collider (LHC), and the one dedicated to ultra relativistic heavy ion collisions, aiming at investigating the properties of the high-density state of QCD matter produced in such events. ALICE started to collect data in proton-proton collisions at the LHC at CERN in November 2009 (with a centre of mass energy [Formula: see text]). Since March 2010 data are being recorded at an energy of [Formula: see text] while from November 7 to December 6 LHC provided Pb-Pb collisions at an energy of [Formula: see text] per nucleon-nucleon pair. In Pb-Pb collisions heavy quarks are regarded as sensitive probes of the interaction dynamics between the parton and medium produced in the collisions, and the energies available at LHC will allow to study the production of heavy flavours with high statistics. Proton-proton data will be used to measure the heavy flavours production cross section to compare with perturbative QCD calculations in an unexplored energy domain and they will provide the reference for the study of Pb-Pb collisions. After a description of the ALICE experiment focused on its heavy flavour related performance, the status of the first analysis on charm production, measured by reconstructing the decays of D0, D+, D*+, and Ds into hadronic and semi-leptonic channels will be presented. An outlook of the same measurements for the upcoming Pb-Pb run will also be discussed.

scholarly journals Heavy-ion physics with the ALICE experiment at the CERN Large Hadron Collider

2012 ◽  
Vol 370 (1961) ◽  
pp. 917-932 ◽  
Author(s):  
J. Schukraft
Keyword(s):  
Large Hadron Collider ◽  
Hadron Collider ◽  
Heavy Ion ◽  
Relativistic Heavy Ion Collisions ◽  
Alice Experiment ◽  
Proton Proton ◽  
Heavy Ion Physics ◽  
Cern Large Hadron Collider ◽  
Ion Collisions ◽  
And Performance

After close to 20 years of preparation, the dedicated heavy-ion experiment A Large Ion Collider Experiment (ALICE) took first data at the CERN Large Hadron Collider (LHC) accelerator with proton collisions at the end of 2009 and with lead nuclei at the end of 2010. After a short introduction into the physics of ultra-relativistic heavy-ion collisions, this article recalls the main design choices made for the detector and summarizes the initial operation and performance of ALICE. Physics results from this first year of operation concentrate on characterizing the global properties of typical, average collisions, both in proton–proton (pp) and nucleus–nucleus reactions, in the new energy regime of the LHC. The pp results differ, to a varying degree, from most quantum chromodynamics-inspired phenomenological models and provide the input needed to fine tune their parameters. First results from Pb–Pb are broadly consistent with expectations based on lower energy data, indicating that high-density matter created at the LHC, while much hotter and larger, still behaves like a very strongly interacting, almost perfect liquid.

scholarly journals (Anti-)(hyper-)nuclei production in Pb–Pb collisions with ALICE at the Large Hadron Collider

2020 ◽  
Vol 1643 (1) ◽  
pp. 012017
Author(s):  
Stefano Trogolo
Keyword(s):  
Hadron Collider ◽  
System Size ◽  
Heavy Ion ◽  
Particle Identification ◽  
Relativistic Heavy Ion Collisions ◽  
Particle Multiplicity ◽  
Charged Particle Multiplicity ◽  
Alice Experiment ◽  
Ion Collisions ◽  
Theoretical Predictions

Abstract In ultra-relativistic heavy-ion collisions a great variety of (anti-)(hyper-)nuclei are produced, namely deuteron, triton, 3He, 4He, hypertriton ( Λ 3 H ) and their antiparticles. The ALICE experiment is the most suited to investigate the production of (hyper-)nuclei at the LHC, thanks to an excellent particle identification and low-material budget detectors. Recent results on (hyper-)nuclei production as a function of transverse momentum (pT) and charged particle multiplicity (dN ch/d η ) in Pb–Pb collisions are presented. The evolution of the production yields with the system size is also shown, via comparison to the results obtained in small collision systems, like pp and p–Pb. The results on the production of (hyper-)nuclei are also compared with the predictions based on a naive coalescence approach and the statistical hadronization models. Furthermore, the latest and currently most precise measurement of the hypertriton lifetime is presented. It is compared with results obtained by different experimental techniques and with theoretical predictions.

scholarly journals ηQ Meson Photoproduction in Ultrarelativistic Heavy Ion Collisions

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Gong-Ming Yu ◽  
Gao-Gao Zhao ◽  
Zhen Bai ◽  
Yan-Bing Cai ◽  
Hai-Tao Yang ◽  
...  
Keyword(s):  
Heavy Ion Collisions ◽  
Hadron Collider ◽  
Heavy Ion ◽  
Relativistic Heavy Ion Collisions ◽  
Heavy Quarkonium ◽  
Color Singlet ◽  
Initial State ◽  
Color Octet ◽  
Ion Collisions ◽  
The Matrix

The transverse momentum distributions for inclusive ηc,b meson described by gluon-gluon interactions from photoproduction processes in relativistic heavy ion collisions are calculated. We considered the color-singlet (CS) and color-octet (CO) components within the framework of Nonrelativistic Quantum Chromodynamics (NRQCD) in the production of heavy quarkonium. The phenomenological values of the matrix elements for the color-singlet and color-octet components give the main contribution to the production of heavy quarkonium from the gluon-gluon interaction caused by the emission of additional gluon in the initial state. The numerical results indicate that the contribution of photoproduction processes cannot be negligible for midrapidity in p-p and Pb-Pb collisions at the Large Hadron Collider (LHC) energies.

scholarly journals Correlation of Heavy and Light Flavors in Simulations

Universe ◽  
2019 ◽  
Vol 5 (5) ◽  
pp. 118
Author(s):  
Eszter Frajna ◽  
Róbert Vértesi
Keyword(s):  
Large Hadron Collider ◽  
Heavy Ion Collisions ◽  
Hadron Collider ◽  
D Meson ◽  
Heavy Ion ◽  
High Energy ◽  
Secondary Vertex ◽  
Alice Experiment ◽  
Ion Collisions ◽  
B Quarks

The ALICE experiment at the Large Hadron Collider (LHC) ring is designed to study the strongly interacting matter at extreme energy densities created in high-energy heavy-ion collisions. In this paper we investigate correlations of heavy and light flavors in simulations at LHC energies at mid-rapidity, with the primary purpose of proposing experimental applications of these methods. Our studies have shown that investigating the correlation images can aid the experimental separation of heavy quarks and help understanding the physics that create them. The shape of the correlation peaks can be used to separate the electrons stemming from b quarks. This could be a method of identification that, combined with identification in silicon vertex detectors, may provide much better sample purity for examining the secondary vertex shift. Based on a correlation picture it is also possible to distinguish between prompt and late contributions to D meson yields.

scholarly journals Aspects of Relativistic Heavy-Ion Collisions

Universe ◽  
2020 ◽  
Vol 6 (5) ◽  
pp. 61 ◽  
Author(s):  
Georg Wolschin
Keyword(s):  
Heavy Ion Collisions ◽  
Initial Conditions ◽  
Hadron Collider ◽  
Heavy Ion ◽  
Charged Hadron ◽  
Distribution Functions ◽  
Relativistic Heavy Ion Collisions ◽  
Short Time Scale ◽  
Relativistic Heavy Ion Collider ◽  
Ion Collisions

The rapid thermalization of quarks and gluons in the initial stages of relativistic heavy-ion collisions is treated using analytic solutions of a nonlinear diffusion equation with schematic initial conditions, and for gluons with boundary conditions at the singularity. On a similarly short time scale of t ≤ 1 fm/c, the stopping of baryons is accounted for through a QCD-inspired approach based on the parton distribution functions of valence quarks, and gluons. Charged-hadron production is considered phenomenologically using a linear relativistic diffusion model with two fragmentation sources, and a central gluonic source that rises with ln 3 ( s N N ) . The limiting-fragmentation conjecture that agrees with data at energies reached at the Relativistic Heavy-Ion Collider (RHIC) is found to be consistent with Large Hadron Collider (LHC) data for Pb-Pb at s N N = 2.76 and 5.02 TeV. Quarkonia are used as hard probes for the properties of the quark-gluon plasma (QGP) through a comparison of theoretical predictions with recent CMS, ALICE and LHCb data for Pb-Pb and p-Pb collisions.

RAPIDITY AND AZIMUTHAL CORRELATION PATTERNS IN NUCLEON-NUCLEON AND RELATIVISTIC HEAVY ION COLLISIONS AT $\sqrt{s} = 200\, {\rm GeV}$

2007 ◽  
Vol 16 (10) ◽  
pp. 3379-3385 ◽  
Author(s):  
MEIJUAN WANG ◽  
YUANFANG WU
Keyword(s):  
Heavy Ion Collisions ◽  
System Size ◽  
Heavy Ion ◽  
Nucleon Nucleon ◽  
Relativistic Heavy Ion Collisions ◽  
Production Mechanism ◽  
Azimuthal Correlation ◽  
Pp Collisions ◽  
Ion Collisions

Rapidity and azimuthal correlation patterns for nucleon and relativistic heavy ion collisions are systematically studied by using PYTHIA for pp collisions, RQMD and AMPT for Au − Au collisions at [Formula: see text], respectively. The results show that the measures are sensitive to the collision particles, system size and production mechanism of the system.

scholarly journals An Experimental Review on Elliptic Flow of Strange and Multistrange Hadrons in Relativistic Heavy Ion Collisions

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Shusu Shi
Keyword(s):  
Large Hadron Collider ◽  
Cross Sections ◽  
Heavy Ion Collisions ◽  
Hadron Collider ◽  
Elliptic Flow ◽  
Heavy Ion ◽  
Relativistic Heavy Ion Collisions ◽  
Relativistic Heavy Ion Collider ◽  
Flow Measurements ◽  
Ion Collisions

Strange hadrons, especially multistrange hadrons, are good probes for the early partonic stage of heavy ion collisions due to their small hadronic cross sections. In this paper, I give a brief review on the elliptic flow measurements of strange and multistrange hadrons in relativistic heavy ion collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC).

scholarly journals Measurement of Open Heavy-Flavour Production in pp and p–Pb Collisions with ALICE at the LHC

2018 ◽  
Vol 46 ◽  
pp. 1860019
Author(s):  
Renu Bala
Keyword(s):  
Cross Section ◽  
Production Cross Section ◽  
Heavy Ion Collisions ◽  
D Mesons ◽  
Production Cross ◽  
Hadron Collider ◽  
Heavy Ion ◽  
Nuclear Modification Factor ◽  
Ion Collisions ◽  
Modification Factor

The Large Hadron Collider at CERN allows us to study heavy-ion collisions at an un- precedented energy. ALICE, A Large Ion Collider Experiment, is the experiment ded- icated to the investigation of heavy-ion collisions. In this contribution, recent open heavy-flavour results from pp collisions at [Formula: see text]= 5.02, 7, 8 and 13 TeV and p–Pb collisions at [Formula: see text] = 5.02 TeV, collected with the ALICE detector during the LHC Run-1 and Run-2 are presented. The results include the production cross section, nuclear modification factor and multiplicity dependence studies of production of D mesons and electrons from heavy-flavour hadron decays at mid-rapidity and of muons from heavy-flavour hadron decays at forward rapidity. Charm production was measured down to [Formula: see text] = 0 GeV/[Formula: see text] in pp and p–Pb collisions. Recent measurements of the production cross section of heavy charmed baryons such as [Formula: see text] (in pp and p–Pb) and [Formula: see text] (in pp) are discussed. The results are compared with theoretical model predictions.

Investigating the microscopic properties of strongly interacting matter with HADES

Open Physics ◽  
2012 ◽  
Vol 10 (6) ◽  
Author(s):  
Tetyana Galatyuk ◽  
Manuel Lorenz
Keyword(s):  
Phase Diagram ◽  
Heavy Ion ◽  
Nucleon Nucleon ◽  
Reference Spectrum ◽  
Medium Effects ◽  
Ion Collisions ◽  
Strongly Interacting ◽  
Energy Domain ◽  
Matter Phase ◽  
Chemical Freeze

AbstractIn the energy domain of 1–2 GeV kinetic energy per nucleon, HADES has measured rare and penetrating probes in elementary and heavy ion collisions. Our results demonstrate that electron pair emission in C+C collisions can essentially be explained as a superposition of independent N+N collisions. HADES results on e+e− production in Ar+KCl collisions, however, show a strong enhancement of the dilepton yield relative to a reference spectrum obtained from elementary nucleon-nucleon reactions, signal the onset of medium effects beyond the superposition of individual N+N collisions. Intriguing results where also obtained from the reconstruction of hadrons with open and hidden strangeness. Analyses of the experimentally obtained hadronic yields measured in Ar+KCl allows to extract the chemical freeze-out conditions in the T -µB phase diagram of strongly interacting matter. While the measured abundance of all reconstructed particles are well described assuming thermalization, the also reconstructed double strange baryon ≡− appears about ten times more abundant than expected. This result will be discussed in the context of the exploration of the nuclear matter phase diagram in the region of finite density. Further investigations to search for significant medium effects, will be followed over the coming years with an upgraded HADES detector.

Sign in / Sign up

Export Citation Format

Share Document