Overview of the results from the NA61/SHINE
strong interaction program
Piotr Podlaskifor the NA61/SHINE Collaboration

NA61/SIHNE two-dimensional scan
In 2017 NA61/SHINE finished a two-dimensional scan in collision energy and size of thecolliding system. Results of the measurements are used to study the phase diagram ofstrongly interacting matter.

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

3 / 19Study of the onset ofdeconfinement

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

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T (MeV)T (MeV)

Onset of deconfinement: step
K+400y ≈0-K400y ≈0200

200
PRELIMINARYAGS SPS

NA61/SHINE
p+p
Be+Be
Ar+Sc

RHIC

1102

LHC

PRELIMINARY

WORLD
p+p
Pb+Pb
Au+Au

AGS SPS104sNN (GeV)

NA61/SHINE
p+p
Be+Be
Ar+Sc

RHIC

102

1LHCWORLD
p+p
Pb+Pb
Au+Au

104
sNN (GeV)

Plateau in the inverse slope parameter T of mT spectra of K ± spectra in Pb+Pb was predictedwithin SMES due to mixed phase of hadron gas and QGP Acta Phys. Polon. B30, 2705 (1999)
Similar structures are visible in other systems
Magnitude of the T parameter increases with the colliding system size
Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

5 / 19

NA61/SHINE
p+p
Be+Be
Ar+Sc

PRELIMINARY〈K+〉/ 〈π+〉K+/ π+ (y≈0)

Onset of deconfinement: horn
WORLD
p+pPb+Pb
Au+Au

0.2

NA61/SHINE
p+p
Be+Be
Ar+Sc

PRELIMINARY

WORLD
p+pPb+Pb
Au+Au

0.2

0.10AGS SPS

RHIC

1102AGS

LHC0104sNN (GeV)

1SPS

10RHIC

102sNN (GeV)

Rapid change in the energy dependence of K + /π + ratio in Pb+Pb collisions indicated the onsetof deconfinement in the SPS energy range, as predicted within SMES
Plateau like structure visible in small systems (p+p and Be+Be)
Ar+Sc systematically higher, shows dependence on collision energy qualitatively similar to p+pand Be+Be (no horn structure)
Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

6 / 19Study of the onset of fireballPiotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

7 / 19System size dependence of K + /π + and T at 150A GeV/c
K + /π +150A GeV/ cPHSD

150A GeV/ c

CE HRG γs=10.2
CE/GCE SMES

0.1

110

K+PHSD

WNM
SMASH

Be+Be

150A GeV/ c

UrQMD

EPOS

p+p

250

200

0.15

0.15

0.05

0.25

T [MeV] (y≈0)

0.25

0.2

T
dynamical models

statistical models
K+/ π+ (y≈0)

K+/ π+ (y≈0)

dynamical models

Ar+Sc

0.1

102

WNM

150

p+pPb+Pb
0.05

EPOS

p+p

1

Be+Be

Ar+Sc10Pb+Pb
210p+p1

Be+Be
10Ar+Sc

Pb+Pb

102

〈W〉

〈W〉

〈W〉

None of the models reproduce K + /π + ratio or T in the whole hW i range
PHSD: Eur.Phys.J.A 56 (2020) 9, 223, arXiv:1908.00451 and private communication;
SMASH: J.Phys.G 47 (2020) 6, 065101 and private communication;
UrQMD and HRG: Phys. Rev. C99 (2019) 3, 034909;
SMES: Acta Phys. Polon. B46 (2015) 10, 1991 - recalculated
Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

p+p: Eur. Phys. J. C77 (2017) 10, 671
Be+Be: Eur. Phys. J. C81 (2021) 1, 73
Ar+Sc: NA61/SHINE preliminary
Pb+Pb: Phys. Rev. C66, 054902 (2002)
20th Lomonosov Conference, August 19-25, 2021

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Unique NA61/SHINE results on heavy ion collisions

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

9 / 19

Search for Critical Point

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

10 / 19

Second factorial moment - proton intermittency
using statistically independent points and cumulative variables:

F2 (M) =1hMPMi=1 ni (ni − 1)ih i=1 ni i2

PM

M - number of pT subdivision intervals
ni - number of particles in i-th pT bin

At the second order phasetransition F2 (M) exhibits apower-law dependence on M:
F2 (M) ∼ (M 2 )φ2Piotr Podlaski (Univ. of Warsaw)

F2 (M) of protons for Ar+Sc at 150A GeV/c and Pb+Pb at
30A GeV/c show no indication of power-law increase withnumber of bins
NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

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Exclusion plots for parameters of simple power-law model

The intermittency index φ2 for a system freezing out at the QCD critical endpoint is
expected to be φ2 = 5/6 assuming that the latter belongs to the 3-D Ising universality
class.
Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

12 / 19

Strangeness production in p+p
at 158 GeV/c

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

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arXiv:2105.09144

Eur.Phys.J.C 80 (2020) 9, 833

Strangeness production in p+p at 158 GeV/c

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

First measurements of Ξ± andΞ0 (1530) in p+p interactionsat CERN SPS energies

Present theoretical models do
not describe the NA61/SHINE
results on strange particles
production in p+p interactions

20th Lomonosov Conference, August 19-25, 2021

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Strangeness enhancement factors

2 dn/dy (A + A)EΞs =hW i dn/dy (p + p)
Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE results give new base-line for strangenessenhancement study in SPS energy range
NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

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NA61/SHINE in 2022-2024

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

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NA61/SHINE program for 2022-2024
What is the mechanism of open charm production?
How does the onset of deconfinement impact open charm production?
How does the formation of quark-gluon plasma impact J/ψ production?
To answer these questions a mean number of charm quark pairs, hcc̄i, produced in A+A
collisions has to be known. Up to now corresponding experimental data does not exist andonly NA61/SHINE can perform this measurement in the near future.

Foreseen NA61/SHINE
resolution is sufficient toanswer addressed questions

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

17 / 19

Summary

Unique 2D scan in system size and the collision energy is completed
So-called step structure visible in p+p, Be+Be, and Ar+Sc
So-called horn structure does not appear in p+p, Be+Be, and Ar+Sc
Unexpected system-size dependence: (p+p ≈ Be+Be) 6= (Ar+Sc 6 Pb+Pb)
So far no convincing indication of the Critical Point
Unique results on multi-strange baryons production in p+p interactions in SPS
NA61/SHINE will measure open charm production in 2022-2024

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

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Thank you

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

19 / 19

Backup

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

20 / 19

NA61/SHINE
Fixed target experiment located at the CERN SPS accelerator:

Beams:
hadrons (π, K , p)pbeam =13-400 GeV/cions (Be, Ar, Xe, Pb)pbeam =13-150A GeV/c√sNN =5.1-16.8(27.4) GeV

Large acceptance hadron spectrometer covers the full forward hemisphere, down to pT = 0
Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

21 / 19

Transition from resonances to strings

Rates of increase of K + /π + and T change
sharply in p+p collisions at SPS energies
The fitted change energy is ≈7 GeV close to the energy of the onset ofdeconfinement ≈8 GeV
Models assuming change from resonances
to string production mechanism show
similar trend

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

22 / 19

Proton intermittency - simple power-law model

Lots of model data sets generated:correlated-to-all ratio: vary from 0.0 to
4.0% (with 0.2 step)
power-law exponent: vary from 0.00 to
1.00 (with 0.05 step)and compared with the experimental data
For the construction of exclusion plots,
statistical uncertainties were calculated using
model with statistics corresponding to the data.

Piotr Podlaski (Univ. of Warsaw)

NA61/SHINE overview

20th Lomonosov Conference, August 19-25, 2021

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