96 research outputs found
New Results from the Cosmic-Ray Program of theNA61/SHINE facility at the CERN SPS
The NA61/SHINE experiment at the SPS accelerator at CERN is a unique facility
for the study of hadronic interactions at fixed target energies. The data
collected with NA61/SHINE is relevant for a broad range of topics in cosmic-ray
physics including ultrahigh-energy air showers and the production of secondary
nuclei and anti-particles in the Galaxy.
Here we present an update of the measurement of the momentum spectra of
anti-protons produced in +C interactions at 158 and 350 GeV/c and
discuss their relevance for the understanding of muons in air showers initiated
by ultrahigh-energy cosmic rays.
Furthermore, we report the first results from a three-day pilot run aimed at
investigating the capability of our experiment to measure nuclear fragmentation
cross sections for the understanding of the propagation of cosmic rays in the
Galaxy. We present a preliminary measurement of the production cross section of
Boron in C+p interactions at 13.5 AGeV/c and discuss prospects for future data
taking to provide the comprehensive and accurate reaction database of nuclear
fragmentation needed in the era of high-precision measurements of Galactic
cosmic rays.Comment: To appear on the proceedings of the 36th International Cosmic Ray
Conference (ICRC 2019
NA49/NA61: results and plans on beam energy and system size scan at the CERN SPS
This paper presents results and plans of the NA49 and NA61/SHINE experiments
at the CERN Super Proton Synchrotron concerning the study of relativistic
nucleus-nucleus interactions. First, the NA49 evidence for the energy threshold
of creating quark-gluon plasma, the onset of deconfinement, in central
lead-lead collisions around 30A GeV is reviewed. Then the status of the
NA61/SHINE systematic study of properties of the onset of deconfinement is
presented. Second, the search for the critical point of strongly interacting
matter undertaken by both experiments is discussed. NA49 measured large
fluctuations at the top SPS energy, 158A GeV, in collisions of light and medium
size nuclei. They seem to indicate that the critical point exists and is
located close to baryonic chemical potential of about 250 MeV. The NA61/SHINE
beam energy and system size scan started in 2009 will provide evidence for the
existence of the critical point or refute the interpretation of the NA49
fluctuation data in terms of the critical point.Comment: 11 pages, invited talk at Quark Matter 201
On saturation of charged hadron production in pp collisions at LHC
First results on charged hadron transverse momentum spectra in pp collisions
obtained by the CMS Collaboration at LHC were analyzed in z-scaling approach.
The first LHC data confirm z-scaling. The saturation regime of the scaling
function psi(z) observed in pp and antp-pp interactions at lower energy sqrt s
= 19-1960 GeV is verified. The saturation of psi(z) for charged hadrons is
found down to z=0.05 at the highest energy sqrt s = 2360 GeV reached till now
at colliders. A microscopic scenario of hadron production is discussed in
connection with search for new signatures of phase transitions in hadron
matter. Constituent energy loss and its dependencies on the transverse momentum
of charged hadrons and collision energy are estimated. The beam energy scan at
LHC in the saturation region is suggested.Comment: LaTeX, 6 pages, 6 figure
Ion Program of Na61/Shine at the CERN SPS
The NA61/SHINE experiment at the CERN SPS aims to discover the critical point
of strongly interacting matter and study properties of the onset of
deconfinement. These goals will be reached by measurements of hadron production
properties in nucleus-nucleus, proton-proton and proton-lead interactions as a
function of collision energy and size of the colliding nuclei. Furthermore,
NA61/SHINE will perform numerous precision measurements needed for neutrino
(T2K) and cosmic-ray (Pierre Auger Observatory and KASCADE) experiments. This
paper summarizes physics arguments for the NA61/SHINE ion program and presents
the status and plans of the experiment.Comment: 8 pages, 4 figures, invited talk at the SQM 2008, typos correcte
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