K*(892)^0 production in p+p interactions at 158 GeV/c from NA61/SHINE

The measurement of $K^{*}(892)^0$ resonance production via its $K^{+}\pi^{-}$ decay mode in inelastic p+p collisions at beam momentum 158~GeV/c ($\sqrt{s_{NN}}=17.3$~GeV) is presented. The data were recorded by the NA61/SHINE hadron spectrometer at the CERN Super Proton Synchrotron. The first ever double differential measurements and $p_T$-integrated spectra of $K^{*}(892)^0$ at beam momenta of 158 GeV/c was done by using the \textit{template} fitting method. The full phase-space yields, mass and width of $K^{*}(892)^0$ mesons are compared with Hadron Resonance Gas models as well as with world data on p+p and nucleus-nucleus collisions.Comment: 12 pages, to be published in proceedings of CPOD 201

Measurements of π±\pi^\pm, K±^\pm, p and pˉ\bar{\textrm{p}} spectra in proton-proton interactions at 20, 31, 40, 80 and 158 GeV/c with the NA61/SHINE spectrometer at the CERN SPS

Measurements of inclusive spectra and mean multiplicities of $\pi^\pm$, K$^\pm$, p and $\bar{\textrm{p}}$ produced in inelastic p+p interactions at incident projectile momenta of 20, 31, 40, 80 and 158 GeV/c ($\sqrt{s} =$ 6.3, 7.7, 8.8, 12.3 and 17.3 GeV, respectively) were performed at the CERN Super Proton Synchrotron using the large acceptance NA61/SHINE hadron spectrometer. Spectra are presented as function of rapidity and transverse momentum and are compared to predictions of current models. The measurements serve as the baseline in the NA61/SHINE study of the properties of the onset of deconfinement and search for the critical point of strongly interacting matter

Multiplicity and transverse momentum fluctuations in inelastic proton-proton interactions at the CERN Super Proton Synchrotron

Measurements of multiplicity and transverse momentum fluctuations of charged particles were performed in inelastic p+p interactions at 20, 31, 40, 80 and 158 GeV/c beam momentum. Results for the scaled variance of the multiplicity distribution and for three strongly intensive measures of multiplicity and transverse momentum fluctuations \$\Delta[P_{T},N]\$, \$\Sigma[P_{T},N]\$ and \$\Phi_{p_T}\$ are presented. For the first time the results on fluctuations are fully corrected for experimental biases. The results on multiplicity and transverse momentum fluctuations significantly deviate from expectations for the independent particle production. They also depend on charges of selected hadrons. The string-resonance Monte Carlo models EPOS and UrQMD do not describe the data. The scaled variance of multiplicity fluctuations is significantly higher in inelastic p+p interactions than in central Pb+Pb collisions measured by NA49 at the same energy per nucleon. This is in qualitative disagreement with the predictions of the Wounded Nucleon Model. Within the statistical framework the enhanced multiplicity fluctuations in inelastic p+p interactions can be interpreted as due to event-by-event fluctuations of the fireball energy and/or volume.Comment: 18 pages, 12 figure

Measurements of π±\pi^\pm, K±K^\pm, KS0K^0_S, Λ\Lambda and proton production in proton-carbon interactions at 31 GeV/cc with the NA61/SHINE spectrometer at the CERN SPS

Measurements of hadron production in p+C interactions at 31 GeV/c are performed using the NA61/ SHINE spectrometer at the CERN SPS. The analysis is based on the full set of data collected in 2009 using a graphite target with a thickness of 4% of a nuclear interaction length. Inelastic and production cross sections as well as spectra of $\pi^\pm$, $K^\pm$, p, $K^0_S$ and $\Lambda$ are measured with high precision. These measurements are essential for improved calculations of the initial neutrino fluxes in the T2K long-baseline neutrino oscillation experiment in Japan. A comparison of the NA61/SHINE measurements with predictions of several hadroproduction models is presented.Comment: v1 corresponds to the preprint CERN-PH-EP-2015-278; v2 matches the final published versio

Hidden strangeness shines in NA61/SHINE

Preliminary results on the ϕ (1020) meson production in inelastic proton-proton collisions measured by the NA61/SHINE experiment at the CERN SPS are presented in these proceedings. The results include the first ever differential pT and y measurements at beam momenta of 40 and 80 GeV and the most ever detailed experimental data at 158GeV. The comparison of p + p to Pb + Pb results shows a non-trivial system size dependence of the widths of the rapidity distributions for ϕ mesons, contrasting with that of other hadrons. The results are furthermore compared to the world data on ϕ meson production, demonstrating the better accuracy achieved by the NA61/SHINE experiment, and to several models. None of the models is found to be able to describe simultaneously the shape of transverse momentum spectra, the shape of rapidity distribution and the total yield

Measurements of multiplicity fluctuations of identified hadrons in inelastic proton–proton interactions at the CERN Super Proton Synchrotron: NA61/SHINE Collaboration

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

Search for the critical point by the NA61/SHINE experiment

NA61/SHINE is a fixed target experiment operating at CERN SPS. Its main goals are to search for the critical point of stronglyinteractingmatterandtostudytheonsetofdeconfinement. Forthesegoalsascanofthetwodimensionalphase diagram (T-μB) is being performed at the SPS by measurements of hadron production in proton-proton, proton-nucleus and nucleus-nucleus interactions as a function of collision energy. In this paper the status of the search for the critical point of strongly interacting matter by the NA61/SHINE Collaboration is presented including recent results on proton intermittency, strongly intensive fluctuation observables of multiplicity and transverse momentum fluctuations. These measurements are expected to be sensitive to the correlation length and, therefore, have the ability to reveal the existence of the critical point via possible non-monotonic behavior. The new NA61/SHINE results are compared to the model predictions