233 research outputs found
Open charm and beauty production in hadron reactions
The production of charmed and beauty hadrons in proton-proton and
proton-antiproton collisions at high energies is analyzed within the modified
quark-gluon string model (QGSM) including the internal motion of quarks in
colliding hadrons. It is shown that using both the QGSM and NLO QCD one can
describe the experimental data rather successfully in a wide region of
transverse momenta. We also present some predictions for the future experiments
on the beauty baryon production in collisions at LHC energies and on the
charmed meson production in reactions at GSI energies.Comment: 8 pages, 10 figures. Talk given at International Conference on Hadron
Structure (HS 09), Tatranska Strba, Slovak Republic, August 29th-September
3rd, 200
Methods to Determine Neutrino Flux at Low Energies:Investigation of the Low Method
We investigate the "low-" method (developed by the CCFR/NUTEV
collaborations) to determine the neutrino flux in a wide band neutrino beam at
very low energies, a region of interest to neutrino oscillations experiments.
Events with low hadronic final state energy (of 1, 2 and 5 GeV)
were used by the MINOS collaboration to determine the neutrino flux in their
measurements of neutrino () and antineutrino (\nub_\mu) total cross
sections. The lowest energy for which the method was used in MINOS is
3.5 GeV, and the lowest \nub_\mu energy is 6 GeV. At these energies, the
cross sections are dominated by inelastic processes. We investigate the
application of the method to determine the neutrino flux for ,
\nub_\mu energies as low as 0.7 GeV where the cross sections are dominated by
quasielastic scattering and (1232) resonance production. We find that
the method can be extended to low energies by using values of 0.25
and 0.50 GeV, which is feasible in fully active neutrino detectors such as
MINERvA.Comment: 25 pages, 32 figures, to be published in European Physics Journal
Quasielastic axial-vector mass from experiments on neutrino-nucleus scattering
We analyze available experimental data on the total and differential
charged-current cross sections for quasielastic neutrino and antineutrino
scattering off nucleons, measured with a variety of nuclear targets in the
accelerator experiments at ANL, BNL, FNAL, CERN, and IHEP, dating from the end
of sixties to the present day. The data are used to adjust the poorly known
value of the axial-vector mass of the nucleon.Comment: 27 pages, 19 figures. Typos corrected; tables, figures and references
added, discussion extended; matches published versio
Pion emission from the T2K replica target: method, results and application
The T2K long-baseline neutrino oscillation experiment in Japan needs precise
predictions of the initial neutrino flux. The highest precision can be reached
based on detailed measurements of hadron emission from the same target as used
by T2K exposed to a proton beam of the same kinetic energy of 30 GeV. The
corresponding data were recorded in 2007-2010 by the NA61/SHINE experiment at
the CERN SPS using a replica of the T2K graphite target. In this paper details
of the experiment, data taking, data analysis method and results from the 2007
pilot run are presented. Furthermore, the application of the NA61/SHINE
measurements to the predictions of the T2K initial neutrino flux is described
and discussed.Comment: updated version as published by NIM
Search for the exotic resonance in the NOMAD experiment
A search for exotic Theta baryon via Theta -> proton +Ks decay mode in the
NOMAD muon neutrino DIS data is reported. The special background generation
procedure was developed. The proton identification criteria are tuned to
maximize the sensitivity to the Theta signal as a function of xF which allows
to study the Theta production mechanism. We do not observe any evidence for the
Theta state in the NOMAD data. We provide an upper limit on Theta production
rate at 90% CL as 2.13 per 1000 of neutrino interactions.Comment: Accepted to European Physics Journal
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
Search for the QCD critical point at SPS energies
Lattice QCD calculations locate the QCD critical point at energies accessible at the CERN Super Proton Synchrotron (SPS). We present average transverse momentum and multiplicity fluctuations, as well as baryon and anti-baryon transverse mass spectra which are expected to be sensitive to effects of the critical point. The future CP search strategy of the NA61/SHINE experiment at the SPS is also discussed.Lattice QCD calculations locate the QCD critical point at energies accessible at the CERN Super Proton Synchrotron (SPS). We present average transverse momentum and multiplicity fluctuations, as well as baryon and anti-baryon transverse mass spectra which are expected to be sensitive to effects of the critical point. The future CP search strategy of the NA61/SHINE experiment at the SPS is also discussed
Open charm measurements in NA61/SHINE at CERN SPS
The measurements of open charm production was proposed as an important tool to investigate the properties of
the hot and dense matter formed in nucleus-nucleus collisions as well as to provide the means for model independent interpretation of the existing data on J/ψ suppression. Recently, the experimental setup of the NA61/SHINE experiment was supplemented with a Vertex Detector which was motivated by the importance and the possibility of the first
direct measurements of open charm meson production in heavy ion collisions at SPS energies. First test data taken in December 2016 on Pb+Pb collisions at 150A GeV/c allowed to validate the general concept of D0 meson detection via its D0 → π+ + K− decay channel and delivered a first indication of open charm production.
The physics motivation of open charm measurements at SPS energies, pilot results on open charm production, and finally, the future plans of open charm measurements in the NA61/SHINE experiment after LS2 are presented
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