scholarly journals Particle production at RHIC and LHC energies

2015 ◽  
Vol 30 (22) ◽  
pp. 1550131 ◽  
Author(s):  
A. Tawfik ◽  
E. Gamal ◽  
A. G. Shalaby
Keyword(s):  
Particle Production ◽  
Hadron Collider ◽  
Center Of Mass ◽  
System Size ◽  
Alice Experiment ◽  
Center Of Mass Energy ◽  
Particle Ratios ◽  
Strangeness Enhancement ◽  
Homogeneous Particle ◽  
Energy Formula

The production of pion, kaon and proton was measured in Pb–Pb collisions at nucleus–nucleus center-of-mass energy [Formula: see text] by the ALICE experiment at Large Hadron Collider (LHC). The particle ratios of these species compared to the RHIC measurements are confronted to the hadron resonance gas (HRG) model and to simulations based on the event generators PYTHIA 6.4.21 and HIJING 1.36. It is found that the homogeneous particle–antiparticle ratios (same species) are fully reproducible by means of HRG and partly by PYTHIA 6.4.21 and HIJING 1.36. The mixed kaon–pion and proton–pion ratios measured at RHIC and LHC energies seem to be reproducible by the HRG model. On the other hand, the strange abundances are underestimated in both event generators. This might be originated to strangeness suppression in the event generators and/or possible strangeness enhancement in the experimental data. It is apparent that the values of kaon–pion ratios are not sensitive to the huge increase of [Formula: see text] from 200 (RHIC) to 2760 GeV (LHC). We conclude that the ratios of produced particle at LHC seem not depending on the system size.

A-DEPENDENCE OF Z-SCALING

2001 ◽  
Vol 16 (07) ◽  
pp. 1281-1301 ◽  
Author(s):  
M. V. TOKAREV ◽  
Yu. A. PANEBRATSEV ◽  
I. ZBOROVSKÝ ◽  
G. P. ŠKORO
Keyword(s):  
Cross Sections ◽  
Particle Production ◽  
Center Of Mass ◽  
Nucleon Nucleon ◽  
Hadron Production ◽  
Scale Transformation ◽  
Invariant Cross Section ◽  
Center Of Mass Energy ◽  
Energy Formula ◽  
Nucleon Nucleon Interaction

The A-dependence of z-scaling in inclusive hadron production in pA collisions at high transverse momenta is studied. The concept of z-scaling based on the fundamental principles of Nature such as self-similarity, locality, scale relativity and fractality reflecting the general features of particle interactions is applied for the description of processes of hadron production in pA collisions. The scaling function ψ is expressed via the invariant cross-section Ed3σ/dq3 and the average multiplicity density dN/dη of particles produced at pseudorapidity η=0 in the corresponding nucleon–nucleon interaction. The independence of the function ψ(z) on the center-of-mass energy [Formula: see text] for particle production near 90° in the NN c.m. system for different nuclei from D up to Pb is shown. The scale transformation z→az, ψ→a-1ψ is used to determine the A-dependence of the transformation parameter a. Based on the properties of z-scaling the dependence of the cross-sections for the π±, K±, and [Formula: see text] hadrons produced in pA collisions on transverse momentum q⊥ in the central region (η=0) at RHIC energies is predicted.

scholarly journals HADRON SPECTRA IN p+p COLLISIONS AT RHIC AND LHC ENERGIES

2013 ◽  
Vol 28 (16) ◽  
pp. 1350066 ◽  
Author(s):  
P. K. KHANDAI ◽  
P. SETT ◽  
P. SHUKLA ◽  
V. SINGH
Keyword(s):  
Hadron Collider ◽  
Center Of Mass ◽  
Heavy Ion ◽  
Relativistic Heavy Ion Collider ◽  
Systematic Analysis ◽  
Center Of Mass Energy ◽  
Hadron Spectra ◽  
200 Gev ◽  
Energy Formula ◽  
Two Parameters

We present the systematic analysis of transverse momentum (pT) spectra of identified hadrons in p+p collisions at Relativistic Heavy Ion Collider ([Formula: see text] and 200 GeV) and at Large Hadron Collider (LHC) energies ([Formula: see text], 2.76 and 7.0 TeV) using phenomenological fit functions. We review various forms of Hagedorn and Tsallis distributions and show their equivalence. We use Tsallis distribution which successfully describes the spectra in p+p collisions using two parameters, Tsallis temperature T which governs the soft bulk spectra and power n which determines the initial production in partonic collisions. We obtain these parameters for pions, kaons and protons as a function of center-of-mass energy [Formula: see text]. It is found that the parameter T has a weak but decreasing trend with increasing [Formula: see text]. The parameter n decreases with increasing [Formula: see text] which shows that production of hadrons at higher energies are increasingly dominated by point like qq scatterings. Another important observation is with increasing [Formula: see text], the separation between the powers for protons and pions narrows down hinting that the baryons and mesons are governed by same production process as one moves to the highest LHC energy.

scholarly journals Multiplicity dependence of $$\pi $$, K, and p production in pp collisions at $$\sqrt{s} = 13$$ TeV

2020 ◽  
Vol 80 (8) ◽  
Author(s):  
S. Acharya ◽  
◽  
D. Adamová ◽  
A. Adler ◽  
J. Adolfsson ◽  
...  
Keyword(s):  
Particle Production ◽  
Center Of Mass ◽  
Particle Multiplicity ◽  
Charged Particle Multiplicity ◽  
Mass Energy ◽  
Pp Collisions ◽  
Proton Proton ◽  
Center Of Mass Energy ◽  
Particle Ratios ◽  
Rapidity Interval

Abstract This paper presents the measurements of $$\pi ^{\pm }$$π±, $$\mathrm {K}^{\pm }$$K±, $$\text {p}$$p and $$\overline{\mathrm{p}} $$p¯ transverse momentum ($$p_{\text {T}}$$pT) spectra as a function of charged-particle multiplicity density in proton–proton (pp) collisions at $$\sqrt{s}\ =\ 13\ \text {TeV}$$s=13TeV with the ALICE detector at the LHC. Such study allows us to isolate the center-of-mass energy dependence of light-flavour particle production. The measurements reported here cover a $$p_{\text {T}}$$pT range from 0.1 to 20 $$\text {GeV}/c$$GeV/c and are done in the rapidity interval $$|y|<0.5$$|y|<0.5. The $$p_{\text {T}}$$pT-differential particle ratios exhibit an evolution with multiplicity, similar to that observed in pp collisions at $$\sqrt{s}\ =\ 7\ \text {TeV}$$s=7TeV, which is qualitatively described by some of the hydrodynamical and pQCD-inspired models discussed in this paper. Furthermore, the $$p_{\text {T}}$$pT-integrated hadron-to-pion yield ratios measured in pp collisions at two different center-of-mass energies are consistent when compared at similar multiplicities. This also extends to strange and multi-strange hadrons, suggesting that, at LHC energies, particle hadrochemistry scales with particle multiplicity the same way under different collision energies and colliding systems.

scholarly journals Study of charged-particle multiplicity fluctuations in pp collisions with Monte Carlo event generators at the LHC

2020 ◽  
Vol 29 (09) ◽  
pp. 2050074
Author(s):  
E. Shokr ◽  
A. H. El-Farrash ◽  
A. De Roeck ◽  
M. A. Mahmoud
Keyword(s):  
Charged Particle ◽  
Particle Production ◽  
Local Density ◽  
Particle Density ◽  
Hadron Collider ◽  
Center Of Mass ◽  
Monte Carlo Event ◽  
Particle Multiplicity ◽  
Charged Particle Multiplicity ◽  
Proton Proton

Proton–Proton ([Formula: see text]) collisions at the Large Hadron Collider (LHC) are simulated in order to study events with a high local density of charged particles produced in narrow pseudorapidty windows of [Formula: see text] = 0.1, 0.2, and 0.5. The [Formula: see text] collisions are generated at center of mass energies of [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] TeV, i.e., the energies at which the LHC has operated so far, using PYTHIA and HERWIG event generators. We have also studied the average of the maximum charged-particle density versus the event multiplicity for all events, using the different pseudorapidity windows. This study prepares for the multi-particle production background expected in a future search for anomalous high-density multiplicity fluctuations using the LHC data.

scholarly journals TOP AND HIGGS PHYSICS AT THE HADRON COLLIDERS

2013 ◽  
Vol 28 (26) ◽  
pp. 1330038 ◽  
Author(s):  
SHABNAM JABEEN
Keyword(s):  
Top Quark ◽  
Hadron Collider ◽  
Center Of Mass ◽  
Charge Asymmetry ◽  
Mass Energy ◽  
Top Quark Mass ◽  
Proton Antiproton ◽  
Proton Proton ◽  
Center Of Mass Energy ◽  
Single Top

This review summarizes the recent results for top quark and Higgs boson measurements from experiments at Tevatron, a proton–antiproton collider at a center-of-mass energy of [Formula: see text], and the Large Hadron Collider, a proton–proton collider at a center-of-mass energy of [Formula: see text]. These results include the discovery of a Higgs-like boson and measurement of its various properties, and measurements in the top quark sector, e.g. top quark mass, spin, charge asymmetry and production of single top quark.

scholarly journals Diboson production at LHC and Tevatron

2014 ◽  
Vol 31 ◽  
pp. 1460279 ◽  
Author(s):  
Jian Wang ◽  
Keyword(s):  
Standard Model ◽  
Center Of Mass ◽  
Mass Energy ◽  
Diboson Production ◽  
Center Of Mass Energy ◽  
Triple Gauge Couplings ◽  
Model Predictions ◽  
Energy Formula ◽  
Anomalous Triple Gauge Couplings ◽  
8 Tev

This is a report at the conference Physics In Collision 2013. The experimental results on physics of diboson production are reviewed. The measurements use pp collision at the LHC with center-of-mass energy [Formula: see text] and 8 TeV, and [Formula: see text] collision at the Tevatron with [Formula: see text]. These include measurements of Wγ, Zγ, WW, WZ and ZZ production. The results are compared with Standard Model predictions, and are interpreted in terms of constraints on charged and neutral anomalous triple gauge couplings.

scholarly journals Collider searches for nonperturbative low-scale gravity states

2015 ◽  
Vol 30 (34) ◽  
pp. 1530061 ◽  
Author(s):  
Douglas M. Gingrich
Keyword(s):  
Large Hadron Collider ◽  
Hadron Collider ◽  
Center Of Mass ◽  
Mass Energy ◽  
Personal View ◽  
Proton Proton ◽  
Center Of Mass Energy ◽  
8 Tev

The possibility of producing nonperturbative low-scale gravity states in collider experiments was first discussed in about 1998. The ATLAS and CMS experiments have searched for nonperturbative low-scale gravity states using the Large Hadron Collider with a proton–proton center-of-mass energy of 8 TeV. These experiments have now seriously confronted the possibility of producing nonperturbative low-scale gravity states which were proposed over 17 years ago. I will summarize the results of the searches, give a personal view of what they mean, and make some predictions for 13 TeV center-of-mass energy. I will also discuss early ATLAS 13 TeV center-of-mass energy results.

Modeling charged-particle multiplicity distributions at LHC

2020 ◽  
Vol 35 (36) ◽  
pp. 2050302
Author(s):  
Amr Radi
Keyword(s):  
High Energy Physics ◽  
Hadron Collider ◽  
Center Of Mass ◽  
Charged Particles ◽  
High Energy ◽  
Particle Multiplicity ◽  
Charged Particle Multiplicity ◽  
Proton Proton ◽  
Center Of Mass Energy ◽  
8 Tev

With many applications in high-energy physics, Deep Learning or Deep Neural Network (DNN) has become noticeable and practical in recent years. In this article, a new technique is presented for modeling the charged particles multiplicity distribution [Formula: see text] of Proton-Proton [Formula: see text] collisions using an efficient DNN model. The charged particles multiplicity n, the total center of mass energy [Formula: see text], and the pseudorapidity [Formula: see text] used as input in DNN model and the desired output is [Formula: see text]. DNN was trained to build a function, which studies the relationship between [Formula: see text]. The DNN model showed a high degree of consistency in matching the data distributions. The DNN model is used to predict with [Formula: see text] not included in the training set. The expected [Formula: see text] had effectively merged the experimental data and the values expected indicate a strong agreement with Large Hadron Collider (LHC) for ATLAS measurement at [Formula: see text], 7 and 8 TeV.

scholarly journals The LUCID Detector for LHC Run-2

Universe ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 11
Author(s):  
Carla Sbarra ◽  
Keyword(s):  
Large Hadron Collider ◽  
Hadron Collider ◽  
Center Of Mass ◽  
Detector Response ◽  
Mass Energy ◽  
Detector Performance ◽  
Center Of Mass Energy ◽  
Long Term Stability ◽  
Early Signal

LUCID (LUminosity Cerenkov Integrating Detector) is the main luminosity monitor of the ATLAS (A Toroidal LHC Apparatus) experiment at the Large Hadron Collider (LHC) and in particular is the only one capable of providing bunch-by-bunch luminosity information, both online and offline, for all beam conditions and luminosity ranges. LUCID-2 refers to the detector upgrade designed to cope with the running conditions to be met in Run-2 (2015–2018): a center of mass energy of 13 TeV, with 50 pp interactions per bunch-crossing on average and a 25 ns bunch-spacing. This report summarizes all changes with respect to the detector deployed in Run-1 (2010–2012), including smaller sensors for higher granularity, new readout electronics for early signal digitization, and a completely new calibration concept guaranteeing long-term stability of the detector response. In addition, the overall detector performance in Run-2 and preliminary results on luminosity measurements are presented.

scholarly journals JET AND HIGH PT MEASUREMENTS WITH THE ALICE EXPERIMENT

2011 ◽  
Vol 20 (07) ◽  
pp. 1533-1538
Author(s):  
◽  
CHRISTIAN KLEIN-BÖSING
Keyword(s):  
Particle Production ◽  
Center Of Mass ◽  
Heavy Ion ◽  
First Year ◽  
Alice Experiment ◽  
Elementary Reactions ◽  
Ion Collisions ◽  
New Energy ◽  
First Results ◽  
Medium Influence

Since the beginning of 2010 the LHC provides p + p collisions at the highest center of mass energies to date, allowing to study high p T particle production and jet properties in a new energy regime. For a clear interpretation and the quantification of the medium influence in heavy-ion collisions on high p T observables a detailed understanding of these elementary reactions is essential. We present first results on the observation of jet-like properties with the ALICE experiment and discuss the performance of jet reconstruction in the first year of data taking.

Sign in / Sign up

Export Citation Format

Share Document