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.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Measurements of multiplicity fluctuations of identified hadrons produced in inelastic p+p interactions at 31, 40, 80, and 158 Formula omitted beam momentum are presented. Three different measures of ...multiplicity fluctuations are used: the scaled variance Formula omitted and strongly intensive measures Formula omitted and Formula omitted. 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.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This paper reports measurements of two-pion femtoscopic correlations in Be+Be collisions at a beam momentum of 150
A
GeV
/
c
(energy available in the center-of-mass system for nucleon pair
s
NN
=
...16.84
GeV) by the NA61/SHINE experiment at the CERN SPS accelerator. The obtained momentum space correlation functions can be well described by a Lévy distributed source model. The transverse mass dependence of the Lévy source parameters is presented, and their possible theoretical interpretations are discussed. The results show that the Lévy exponent
α
is approximately constant as a function of
m
T
, and far from both the Gaussian case of
α
=
2
or the conjectured value at the critical endpoint,
α
=
0.5
. The radius scale parameter
R
shows a slight decrease in
m
T
, which can be explained as a signature of transverse flow. Finally, an approximately constant trend of the intercept parameter
λ
as a function of
m
T
was observed, similar to previous NA44 S + Pb results (obtained with a Gaussian approximation, but unlike RHIC results).
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This paper presents measurements of production cross sections and inelastic cross sections for the following reactions: 60 GeV/c protons with C, Be, Al targets and 120 GeV/c protons with C and Be ...targets. The analysis is performed using the NA61/SHINE spectrometer at the CERN Super Proton Synchrotron. First measurements are obtained using protons at 120 GeV/c, while the results for protons at 60 GeV/c are compared with previously published measurements. These interaction cross section measurements are critical inputs for neutrino flux prediction in current and future accelerator-based long-baseline neutrino experiments.
Abstract
The measurement of
$$K^{*}(892)^0$$
K
∗
(
892
)
0
resonance production via its
$$K^{+}\pi ^{-}$$
K
+
π
-
decay mode in inelastic p+p collisions at beam momentum 158
$$\text{ Ge }\text{ V ...}\!/\!c$$
Ge
V
/
c
(
$$\sqrt{s_{NN}}=17.3$$
s
NN
=
17.3
$$\text{ Ge }\text{ V }$$
Ge
V
) is presented. The data were recorded by the NA61/SHINE hadron spectrometer at the CERN Super Proton Synchrotron. The
template
method was used to extract the
$$K^{*}(892)^0$$
K
∗
(
892
)
0
signal and double-differential transverse momentum and rapidity spectra were obtained. The full phase-space mean multiplicity of
$$K^{*}(892)^0$$
K
∗
(
892
)
0
mesons was found to be
$$(78.44 \pm 0.38 \mathrm {(stat)} \pm 6.0 \mathrm {(sys)) \cdot 10^{-3}}$$
(
78.44
±
0.38
(
stat
)
±
6.0
(
sys
)
)
·
10
-
3
. The NA61/SHINEresults are compared with the
Epos1.99
and Hadron Resonance Gas models as well as with world data from p+p and nucleus–nucleus collisions.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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
π
±
,
K
±
,
p
and
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
Ge
V
/
c
. The analysis uses the 10% most central collisions, where the observed forward energy defines centrality. The energy dependence of the
K
±
/
π
±
ratios as well as of inverse slope parameters of the
K
±
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.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Measurements of
K
∗
(
892
)
0
resonance production via its
K
+
π
-
decay mode in inelastic
p+p
collisions at beam momenta 40 and 80
GeV
/
c
(
s
NN
=
8.8
and 12.3
GeV
) are presented. The data were ...recorded by the NA61/SHINE hadron spectrometer at the CERN Super Proton Synchrotron. The
template
method was used to extract the
K
∗
(
892
)
0
signal. Transverse momentum and rapidity spectra were obtained. The mean multiplicities of
K
∗
(
892
)
0
mesons were found to be
(
35.1
±
1.3
(
stat
)
±
3.6
(
sys
)
)
·
10
-
3
at 40
GeV
/
c
and
(
58.3
±
1.9
(
stat
)
±
4.9
(
sys
)
)
·
10
-
3
at 80
GeV
/
c
. The NA61/SHINE results are compared with the
Epos1.99
and Hadron Resonance Gas models as well as with world data. The transverse mass spectra of
K
∗
(
892
)
0
mesons and other particles previously reported by NA61/SHINE were fitted within the Blast-Wave model. The transverse flow velocities are close to 0.1–0.2 of the speed of light and are significantly smaller than the ones determined in heavy nucleus-nucleus interactions at the same beam momenta.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The production of
K
S
0
mesons in inelastic
p+p
collisions at beam momentum 158
GeV
/
c
(
s
NN
=
17.3
GeV
) was measured with the NA61/SHINE spectrometer at the CERN Super Proton Synchrotron. ...Double-differential distributions were obtained in transverse momentum and rapidity. The mean multiplicity of
K
S
0
was determined to be
0.162
±
0.001
(
s
t
a
t
.
)
±
0.011
(
s
y
s
.
)
. The results on
K
S
0
production are compared with model predictions (
EPOS 1.99
, SMASH 2.0, PHSD and UrQMD 3.4 models) as well as with published world data.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This paper presents multiplicity measurements of $K^0_S$, Λ, and $\bar{Λ}$ produced in 120 GeV/c proton-carbon interactions. The measurements were made using data collected at the NA61/SHINE ...experiment during two different periods. Decays of these neutral hadrons impact the measured π+, π-, p and $\bar{p}$ multiplicities in the 120 GeV/c proton-carbon reaction, which are crucial inputs for long-baseline neutrino experiment predictions of neutrino beam flux. The double-differential multiplicities presented here will be used to more precisely measure charged-hadron multiplicities in this reaction, and to reweight neutral hadron production in neutrino beam Monte Carlo simulations.
We present measurements of ρ0, ω and K∗0 spectra in π-+ C production interactions at 158 GeV/c and ρ0 spectra at 350 GeV/c using the NA61/SHINE spectrometer at the CERN SPS. Spectra are presented as ...a function of the Feynman’s variable xF in the range 0<xF<1 and 0<xF<0.5 for 158 and 350 GeV/c respectively. Furthermore, we show comparisons with previous measurements and predictions of several hadronic interaction models. These measurements are essential for a better understanding of hadronic shower development and for improving the modeling of cosmic ray air showers.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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