scholarly journals Measurements of multiplicity fluctuations of identified hadrons in inelastic proton–proton interactions at the CERN Super Proton Synchrotron

2021 ◽  
Vol 81 (5) ◽  
Author(s):  
A. Acharya ◽  
H. Adhikary ◽  
A. Aduszkiewicz ◽  
K. K. Allison ◽  
E. V. Andronov ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Data Analysis ◽  
Collision Energy ◽  
Beam Momentum ◽  
Particle Identification ◽  
Proton Synchrotron ◽  
Super Proton Synchrotron ◽  
Proton Proton ◽  
Intensive Quantities ◽  
Multiplicity Distributions

AbstractMeasurements of multiplicity fluctuations of identified hadrons produced in inelastic p+p interactions at 31, 40, 80, and 158 $$\text {Ge}\text {V}/c$$ Ge / c beam momentum are presented. Three different measures of multiplicity fluctuations are used: the scaled variance $$\omega $$ ω and strongly intensive measures $$\Sigma $$ Σ and $$\Delta $$ Δ . These fluctuation measures involve second and first moments of joint multiplicity distributions. Data analysis is preformed using the Identity method which corrects for incomplete particle identification. Strongly intensive quantities are calculated in order to allow for a direct comparison to corresponding results on nucleus–nucleus collisions. The results for different hadron types are shown as a function of collision energy. A comparison with predictions of string-resonance Monte-Carlo models: Epos, Smash and Venus, is also presented.

scholarly journals Measurements of $$\pi ^-$$ production in $$^7$$Be + $$^9$$Be collisions at beam momenta from 19A to 150$$A\,\text{ GeV }\!/\!c$$ in the NA61/SHINE experiment at the CERN SPS

2020 ◽  
Vol 80 (10) ◽  
Author(s):  
A. Acharya ◽  
H. Adhikary ◽  
A. Aduszkiewicz ◽  
K. K. Allison ◽  
E. V. Andronov ◽  
...  
Keyword(s):  
Particle Production ◽  
Nucleon Nucleon ◽  
Particle Identification ◽  
Hadronic Matter ◽  
Transverse Mass ◽  
Proton Synchrotron ◽  
Super Proton Synchrotron ◽  
The Mean ◽  
Onset Of Deconfinement ◽  
Formula Method

AbstractThe NA61/SHINE collaboration studies at the CERN Super Proton Synchrotron (SPS) the onset of deconfinement in hadronic matter by the measurement of particle production in collisions of nuclei with various sizes at a set of energies covering the SPS energy range. This paper presents results on inclusive double-differential spectra and mean multiplicities of $$\pi ^{-}$$ π - mesons produced in the 5% most central$$^7$$ 7 Be + $$^9$$ 9 Be collisions at beam momenta of 19A, 30A, 40A, 75A and 150$$A\,\text{ GeV }\!/\!c$$ A GeV / c obtained by the so-called $$h^-$$ h - method which does not require any particle identification. The shape of the transverse mass spectra differs from the shapes measured in central Pb + Pb collisions and inelastic p+p interactions. The normalized width of the rapidity distribution decreases with increasing collision energy and is in between the results for inelastic nucleon–nucleon and central Pb + Pb collisions. The mean multiplicity of pions per wounded nucleon in central$$^7$$ 7 Be + $$^9$$ 9 Be collisions is close to that in central Pb + Pb collisions up to 75$$A\,\text{ GeV }\!/\!c$$ A GeV / c . However, at the top SPS energy the result lies between those for nucleon–nucleon and Pb + Pb interactions. The results are discussed in the context of predictions for the onset of deconfinement at the CERN SPS collision energies.

scholarly journals Searching for Minimum in Dependence of Squared Speed-of-Sound on Collision Energy

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Fu-Hu Liu ◽  
Li-Na Gao ◽  
Roy A. Lacey
Keyword(s):  
Speed Of Sound ◽  
Center Of Mass ◽  
Incident Beam ◽  
Gluon Plasma ◽  
Beam Momentum ◽  
Proton Synchrotron ◽  
Super Proton Synchrotron ◽  
Center Of Mass Energy ◽  
Knee Point ◽  
Charged Pions

Experimental results of the rapidity distributions of negatively charged pions produced in proton-proton (p-p) and beryllium-beryllium (Be-Be) collisions at different beam momentums, measured by the NA61/SHINE Collaboration at the super proton synchrotron (SPS), are described by a revised (three-source) Landau hydrodynamic model. The squared speed-of-sound parametercs2is then extracted from the width of rapidity distribution. There is a local minimum (knee point) which indicates a softest point in the equation of state (EoS) appearing at about40A GeV/c(or 8.8 GeV) incs2excitation function (the dependence ofcs2on incident beam momentum (or center-of-mass energy)). This knee point should be related to the searching for the onset of quark deconfinement and the critical point of quark-gluon plasma (QGP) phase transition.

scholarly journals Study of energy response and resolution of the ATLAS Tile Calorimeter to hadrons of energies from 16 to 30 GeV

2021 ◽  
Vol 81 (6) ◽  
Author(s):  
Jalal Abdallah ◽  
Stylianos Angelidakis ◽  
Giorgi Arabidze ◽  
Nikolay Atanov ◽  
Johannes Bernhard ◽  
...  
Keyword(s):  
Large Hadron Collider ◽  
Hadron Collider ◽  
Simulated Data ◽  
Simulation Program ◽  
Proton Synchrotron ◽  
Energy Response ◽  
Super Proton Synchrotron ◽  
Proton Proton

AbstractThree spare modules of the ATLAS Tile Calorimeter were exposed to test beams from the Super Proton Synchrotron accelerator at CERN in 2017. The detector’s measurements of the energy response and resolution to positive pions and kaons, and protons with energies ranging from 16 to 30 GeV are reported. The results have uncertainties of a few percent. They were compared to the predictions of the Geant4-based simulation program used in ATLAS to estimate the response of the detector to proton-proton events at the Large Hadron Collider. The determinations obtained using experimental and simulated data agree within the uncertainties.

scholarly journals Two-particle correlations in azimuthal angle and pseudorapidity in central $$^7\hbox {Be}+{}^9\hbox {Be}$$ collisions at the CERN Super Proton Synchrotron

2020 ◽  
Vol 80 (12) ◽  
Author(s):  
A. Aduszkiewicz ◽  
◽  
E. V. Andronov ◽  
T. Antićić ◽  
V. Babkin ◽  
...  
Keyword(s):  
Azimuthal Angle ◽  
Incident Beam ◽  
Charged Hadron ◽  
Proton Synchrotron ◽  
Super Proton Synchrotron ◽  
Proton Proton ◽  
Pair Correlations ◽  
Proton Collisions ◽  
Hadron Pairs ◽  
Proton Proton Collisions

AbstractA measurement of charged hadron pair correlations in two-dimensional $$\Delta \eta \Delta \phi $$ Δ η Δ ϕ   space is presented. The analysis is based on total 30 million central Be + Be collisions observed in the NA61/SHINE detector at the CERN SPS for incident beam momenta of 19A, 30A, 40A, 75A, and 150A $$\text {Ge} \text {V}/c$$ Ge / c . Measurements were carried out for unlike-sign and like-sign charge hadron pairs independently. The $$C(\Delta \eta ,\Delta \phi )$$ C ( Δ η , Δ ϕ ) correlation functions were compared with results from a similar analysis on p + p interactions at similar beam momenta per nucleon. General trends of the back-to-back correlations are similar in central Be + Be collisions and p + p interactions, but are suppressed in magnitude due to the increased combinatorial background. Predictions from the Epos and UrQMD models are compared to the measurements. Evolution of an enhancement around $$(\Delta \eta ,\Delta \phi ) = (0,0)$$ ( Δ η , Δ ϕ ) = ( 0 , 0 ) with incident energy is observed in central Be + Be collisions. It is not predicted by both models and almost non-existing in proton–proton collisions at the same momentum per nucleon.

scholarly journals Latest Results from the NA61/SHINE Experiment

KnE Energy ◽  
2018 ◽  
Vol 3 (1) ◽  
pp. 188 ◽  
Author(s):  
D T Larsen
Keyword(s):  
Critical Point ◽  
Energy Dependence ◽  
System Size ◽  
Beam Momentum ◽  
Strong Interactions ◽  
Proton Synchrotron ◽  
Momentum Range ◽  
Super Proton Synchrotron ◽  
Hadron Spectra ◽  
Onset Of Deconfinement

The NA61/SHINE experiment at the CERN Super Proton Synchrotron is pursuing a rich programme on strong interactions, which covers the study of the onset of deconfinement and aims to discover the critical point of strongly interacting matter by performing an energy and system-size scan over the full CERN SPS beam momentum range. So far the scans of p+p, p+Pb, Be+Be, and Ar+Sc interactions have been completed, samples of Pb+Pb data at three energies have already been taken and Xe+La collisions will be registered this year. Results from the different reactions are now emerging, in particular the energy dependence of hadron spectra and yields as well as fluctuations. This contribution presents status and preliminary results from this effort, as well as an outlook for future extensions of the strong interactions programme.

Sign in / Sign up

Export Citation Format

Share Document