26 research outputs found
Measurements of and production in proton–proton interactions at in the NA61/SHINE experiment
Double-differential yields of and
resonances produced in \pp interactions
were measured at a laboratory beam momentum of 158~\GeVc. This measurement is
the first of its kind in \pp interactions below LHC energies. It was performed
at the CERN SPS by the \NASixtyOne collaboration. Double-differential
distributions in rapidity and transverse momentum were obtained from a sample
of 2610 inelastic events. The spectra are extrapolated to full phase
space resulting in mean multiplicity of (6.73
0.25 0.67) and (2.71
0.18 0.18). The rapidity and transverse momentum
spectra and mean multiplicities were compared to predictions of string-hadronic
and statistical model calculations
Measurements of and production in proton–proton interactions at in the NA61/SHINE experiment
International audienceThe production of and hyperons in inelastic p+p interactions is studied in a fixed target experiment at a beam momentum of 158 . Double differential distributions in rapidity and transverse momentum are obtained from a sample of 33M inelastic events. They allow to extrapolate the spectra to full phase space and to determine the mean multiplicity of both and . The rapidity and transverse momentum spectra are compared to transport model predictions. The mean multiplicity in inelastic p+p interactions at 158 is used to quantify the strangeness enhancement in A+A collisions at the same centre-of-mass energy per nucleon pair
Monte Carlo Studies of the MPD Detector Performance for the Measurement of Hypertritons in Heavy-Ion Collisions at NICA Energies
International audienceHeavy-ion collisions at NICA energies provide a unique opportunity for the study of the production of hypernuclei in dense baryonic matter. In this paper, the details of the reconstruction procedure for hypertritons with the MPD detector in Bi + Bi collisions at NICA energies are presented
Measurements of total production cross sections for +C, +Al, +C, and +Al at 60 GeV/c and +C and +Al at 31 GeV/c
International audienceThis paper presents several measurements of total production cross sections and total inelastic cross sections for the following reactions: π++C, π++Al, K++C, K++Al at 60 GeV/c, π++C and π++Al at 31 GeV/c. The measurements were made using the NA61/SPS Heavy Ion and Neutrino Experiment spectrometer at the CERN Super Proton Synchrotron (SPS). Comparisons with previous measurements are given and good agreement is seen. These interaction cross sections measurements are a key ingredient for neutrino flux prediction from the reinteractions of secondary hadrons in current and future accelerator-based long-baseline neutrino experiments
Spectra and mean multiplicities of π− in central 40Ar+45Sc collisions at 13A, 19A, 30A, 40A, 75A and 150A GeV/c beam momenta measured by the NA61/SHINE spectrometer at the CERN SPS
The physics goal of the strong interaction program of the NA61/SHINE experiment at the CERN Super Proton Synchrotron (SPS) is to study the phase diagram of hadronic matter by a scan of particle production in collisions of nuclei with various sizes at a set of energies covering the SPS energy range. This paper presents differential inclusive spectra of transverse momentum, transverse mass and rapidity of π− mesons produced in central 40Ar+45Sc collisions at beam momenta of 13A, 19A, 30A, 40A, 75A and 150A Ge V /c. Energy and system size dependence of parameters of these distributions – mean transverse mass, the inverse slope parameter of transverse mass spectra, width of the rapidity distribution and mean multiplicity – are presented and discussed. Furthermore, the dependence of the ratio of the mean number of produced pions to the mean number of wounded nucleons on the collision energy was derived. The results are compared to predictions of several models
Measurements of higher-order cumulants of multiplicity and net-electric charge distributions in inelastic proton-proton interactions by NA61/SHINE
This paper presents the energy dependence of multiplicity and net-electric charge fluctuations in interactions at beam momenta 20, 31, 40, 80, and 158 GeV/. Results are corrected for the experimental biases and quantified with the use of cumulants and factorial cumulants. Data are compared with the Epos1.99 and FTFP-BERT model predictions
Excess of charged over neutral meson production in high-energy collisions of atomic nuclei
International audienceCollisions of atomic nuclei at relativistic velocities produce new particles, predominantly mesons containing one valence quark and one valence anti-quark. These particles are produced in strong interactions, which preserve an approximate symmetry between up () and down () quarks. In the case of meson production, if this symmetry were exact, it would result in equal numbers of charged ( and ) and neutral ( and ) mesons in the final state. In this Letter, we report a measurement of the relative abundance of charged over neutral meson production in collisions of argon and scandium nuclei at a center-of-mass energy of 11.9~GeV per nucleon pair. We find that production of and mesons at mid-rapidity displays a significant excess of relative to that of the neutral mesons. The origin of this unexpected excess remains to be elucidated
Measurements of multiplicity fluctuations of identified hadrons in inelastic proton–proton interactions at the CERN Super Proton Synchrotron
Measurements of multiplicity fluctuations of identified hadrons produced in inelastic p+p interactions at 31, 40, 80, and 158 GeV/c beam momentum are presented. Three different measures of multiplicity fluctuations are used: the scaled variance ω and strongly intensive measures Σ and 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
KS0 meson production in inelastic p+p interactions at 158 GeV/c beam momentum measured by NA61/SHINE at the CERN SPS
The production of K0S mesons in inelastic p+p collisions at beam momentum 158 GeV /c (sNN√=17.3 GeV ) was measured with the NA61/SHINE spectrometer at the CERN Super Proton Synchrotron. Double-differential distributions were obtained in transverse momentum and rapidity. The mean multiplicity of K0S was determined to be 0.162±0.001(stat.)±0.011(sys.) . The results on K0S production are compared with model predictions (EPOS 1.99, SMASH 2.0, PHSD and UrQMD 3.4 models) as well as with published world data.publishedVersio