14 research outputs found
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
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
Optimal multilevel methods for H(grad), H(curl), and H(div) systems on graded and unstructured grids
Measurements of π±, K±, p and p¯ spectra in 7Be+9Be collisions at beam momenta from 19A to 150A GeV/c with the NA61/SHINE spectrometer at the CERN SPS
The NA61/SHINE experiment at the CERN Super Proton Synchrotron (SPS) studies the onset of deconf inement in hadron 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 results on inclusive double-differential spectra, transverse momentumandrapidity distributions and mean multiplicities of π±, K±, p and ¯p produced in the 20% most central 7Be+9Be collisions at beam momenta of 19A,30A,40A,75A and 150A GeV/c. The energy dependence of the K±/π± ratios as well as of inverse slope parameters of the K± transverse mass distributions are close to those found in inelastic p+p reactions. The new results are compared to the world data on p+p and Pb+Pb collisions as well as to predictions of the Epos, Urqmd, Ampt, Phsd and Smash models
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 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
Measurements of production in Be+Be collisions at beam momenta from 19 to 150GeV/ in the NA61/SHINE experiment at the CERN SPS
International audienceThe 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 mesons produced in the 5% most centralBe + Be collisions at beam momenta of 19A, 30A, 40A, 75A and 150 obtained by the so-called 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 centralBe + Be collisions is close to that in central Pb + Pb collisions up to 75. 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