In this paper, we analyze the correlations between the mean transverse momentum and the multiplicity of charged particles in proton–proton collisions using four different models: EPOS, SMASH, PHSD ...and UrQMD. Three strongly intensive quantities, as well as second- and third-order cumulants of transverse momentum, were chosen as variables for the resaerch. In the dependences of strongly intensive quantities on energy, discrepancies between the models were found. In the model SMASH, both for strongly intensive quantities and for cumulants, a certain ‘‘wave’’ arise, which can become evidence of a transition from the resonance regime to strings. Such a nontrivial behavior of
correlations in
collisions as ‘‘baseline’’ may later cause difficulties in explaining the results for
collisions. All models coincide with the prediction of the hydrodynamic model. Experimental results obtained at MPD/NICA can clarify this model analysis.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This paper presents multiplicity measurements of charged hadrons produced in 120 GeV/$c$ proton-carbon interactions. The measurements were made using data collected at the NA61/SHINE experiment ...during two different data-taking periods, with increased phase space coverage in the second configuration due to the addition of new subdetectors. Particle identification via $dE/dx$ was employed to obtain double-differential production multiplicities of $\pi^+$, $\pi^-$, $p$, $\bar{p}$, $K^+$ and $K^-$. These measurements are presented as a function of laboratory momentum in intervals of laboratory polar angle covering the range from 0 to 450 mrad. They provide crucial inputs for current and future long-baseline neutrino experiments, where they are used to estimate the initial neutrino flux.
Full text
Available for:
CMK, CTK, FMFMET, IJS, NUK, PNG, UM
The critical point of dense, strongly interacting matter is searched for at the CERN SPS in
40
Ar +
45
Sc collisions at 150
A
Ge V /
c
. The dependence of second-order scaled factorial moments of ...proton multiplicity distribution on the number of subdivisions of transverse momentum space is measured. The intermittency analysis is performed using both transverse momentum and cumulative transverse momentum. For the first time, statistically independent data sets are used for each subdivision number. The obtained results do not indicate any statistically significant intermittency pattern. An upper limit on the fraction of correlated proton pairs and the power of the correlation function is obtained based on a comparison with the Power-law Model developed for this purpose.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Measurements of $K_S^0$ meson production via its $\pi^{+} \pi^{-}$ decay mode
in inelastic $\textit{p+p}$ interactions at incident projectile momenta of 31,
40 and 80 GeV/$c$ ($\sqrt{s_{NN}}=7.7, ...8.8$ and $12.3$ GeV, respectively) are
presented. The data were recorded by the NA61/SHINE spectrometer at the CERN
Super Proton Synchrotron. Double-differential distributions were obtained in
transverse momentum and rapidity. The mean multiplicities of $K_S^0$ mesons
were determined to be $(5.95 \pm 0.19 (stat) \pm 0.22 (sys)) \times 10^{-2}$ at
31 GeV/$c$, $(7.61 \pm 0.13 (stat) \pm 0.31 (sys)) \times 10^{-2}$ at 40
GeV/$c$ and $(11.58 \pm 0.12 (stat) \pm 0.37 (sys)) \times 10^{-2}$ at 80
GeV/$c$. The results on $K^{0}_{S}$ production are compared with model
calculations (Epos1.99, SMASH 2.0 and PHSD) as well as with published data from
other experiments.
The critical point of strongly interacting matter is searched for at the CERN
SPS by the NA61/SHINE experiment in central $^{40}$Ar +$^{45}$Sc collisions at
13$A$, 19$A$, 30$A$, 40$A$, and 75$A$ ...GeV/$c$. The dependence of the
second-order scaled factorial moments of proton multiplicity distributions on
the number of subdivisions in transverse momentum space is measured. The
intermittency analysis uses statistically independent data sets for every
subdivision in transverse and cumulative-transverse momentum variables.
The results obtained do not indicate the searched intermittent pattern. An
upper limit on the fraction of correlated protons and the intermittency index
is obtained based on a comparison with the Power-law Model.
Collisions 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 ($u$) and down ($d$) quarks. In the case of $K$
meson production, if this symmetry were exact, it would result in equal numbers
of charged ($K^+$ and $K^-$) and neutral ($K^0$ and $\overline K^0$) mesons in
the final state. In this Letter, we report a measurement of the relative
abundance of charged over neutral $K$ 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 $\mathit{K^+}$ and $\mathit{K^-}$ mesons at
mid-rapidity is $(18.4\pm 6.1)\%$ higher than that of the neutral $K$ mesons.
The origin of this unexpected excess remains to be elucidated.
Eur. Phys. J. C 84, 416 (2024) The NA61/SHINE experiment at the CERN Super Proton Synchrotron studies the
onset of deconfinement in strongly interacting matter through a beam energy
scan of particle ...production in collisions of nuclei of varied sizes. This paper
presents results on inclusive double-differential spectra, transverse momentum
and rapidity distributions and mean multiplicities of $\pi^\pm$, $K^\pm$, $p$
and $\bar{p}$ produced in $^{40}$Ar+$^{45}$Sc collisions at beam momenta of
13$A$, 19$A$, 30$A$, 40$A$, 75$A$ and 150$A$~\GeVc. The analysis uses the 10\%
most central collisions, where the observed forward energy defines centrality.
The energy dependence of the $K^\pm$/$\pi^\pm$ ratios as well as of inverse
slope parameters of the $K^\pm$ transverse mass distributions are placed in
between those found in inelastic $p$+$p$ and central Pb+Pb collisions. The
results obtained here establish a system-size dependence of hadron production
properties that so far cannot be explained either within statistical or
dynamical models.
This paper presents multiplicity measurements of charged hadrons produced in
120 GeV/$c$ proton-carbon interactions. The measurements were made using data
collected at the NA61/SHINE experiment ...during two different data-taking
periods, with increased phase space coverage in the second configuration due to
the addition of new subdetectors. Particle identification via $dE/dx$ was
employed to obtain double-differential production multiplicities of $\pi^+$,
$\pi^-$, $p$, $\bar{p}$, $K^+$ and $K^-$. These measurements are presented as a
function of laboratory momentum in intervals of laboratory polar angle covering
the range from 0 to 450 mrad. They provide crucial inputs for current and
future long-baseline neutrino experiments, where they are used to estimate the
initial neutrino flux.
