# Investigating the nature of the K\*\_0(700) state with $\pi^{\pm}K^0_S$ correlations at the LHC

Shreyasi Acharya, Dagmar Adamova, Gianluca Aglieri Rinella, Luca Aglietta, Michelangelo Agnello, Neelima Agrawal, Zubayer Ahammed, Shakeel Ahmad, Sang Un Ahn, Ishaan Ahuja, et al.

► To cite this version:

Shreyasi Acharya, Dagmar Adamova, Gianluca Aglieri Rinella, Luca Aglietta, Michelangelo Agnello, et al.. Investigating the nature of the K\*\_0(700) state with $\pi^{\pm}K^0_S$ correlations at the LHC. Phys.Lett.B, 2024, 856, pp.138915. 10.1016/j.physletb.2024.138915. hal-04372040

HAL Id: hal-04372040

https://hal.science/hal-04372040v1

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Letter

# Investigating the composition of the $K_0^*(700)$ state with $\pi^\pm K_S^0$ correlations at the LHC

ALICE Collaboration *

<figure><img src="image_2.png" /></figure>

## ARTICLE INFO

Editor: M. Doser

Dataset link: https://www.hepdata.net/record/ins2739149

## ABSTRACT

The first measurements of femtoscopic correlations with the particle pair combinations $\pi^\pm K_S^0$ in pp collisions at $\sqrt{s} = 13$ TeV at the Large Hadron Collider (LHC) are reported by the ALICE experiment. Using the femtoscopic approach, it is shown that it is possible to study the elusive $K_0^*(700)$ particle that has been considered a tetraquark candidate for over forty years. Source and final-state interaction parameters are extracted by fitting a model assuming a Gaussian source to the experimentally measured two-particle correlation functions. The final-state interaction in the $\pi^\pm K_S^0$ system is modeled through a resonant scattering amplitude, defined in terms of a mass and a coupling parameter, The extracted mass and Breit–Wigner width, derived from the coupling parameter, of the final-state interaction are found to be consistent with previous measurements of the $K_0^*(700)$. The small value and increase of the correlation strength with increasing source size support the hypothesis that the $K_0^*(700)$ is a four-quark state, i.e. a tetraquark state of the form $(q_1, \bar{q}_2, q_3, \bar{q}_3)$ in which $q_1, q_2$ and $q_3$ indicate the flavor of the valence quarks of the $\pi$ and $K_S^0$. This latter trend is also confirmed via a simple geometric model that assumes a tetraquark structure of the $K_0^*(700)$ resonance.

## 1. Introduction

Femtoscopy with identical charged pions has been a useful tool for many years to experimentally probe the geometry of the space-time structure of the freeze-out probability distribution in high-energy pp and heavy-ion collisions [1]. Identical-kaon femtoscopic measurements have also been carried out to complement the identical pion studies, examples of which are measurements in Au–Au collisions at center-of-mass energy per nucleon pair $\sqrt{s_{NN}} = 200$ GeV at the Relativistic Heavy-Ion Collider by the STAR Collaboration [2] ($K_S^0 K_S^0$) and PHENIX Collaboration [3] ($K^\pm K^\pm$), and for pp collisions at $\sqrt{s} = 5.02, 7$, and 13 TeV and Pb–Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV at the CERN LHC by the ALICE Collaboration [4–7] ($K_S^0 K_S^0$ and $K^\pm K^\pm$).

In the femtoscopic method, the momentum correlations of pairs of particles when interactions with the other particles in the collision system cease, i.e. during “freeze out” [8], can be utilized to get insight into the strength of the pair interaction, i.e. the final-state interaction (FSI), at low relative momentum. The homogeneity region size, the strength, and even the nature of the FSI at freeze out can be determined by fitting the experimental two-particle correlation function to a model based on the FSI. Results on non-identical kaon femtoscopy with $K_S^0 K_S^\pm$ pairs were published by ALICE in pp collisions at $\sqrt{s} = 5.02, 7$, and 13 TeV and Pb–Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV [7,9,10]. Although the general goals

of non-identical kaon femtoscopy studies overlap with those for identical kaon femtoscopy, e.g. to extract information about the space–time geometry of the collision region and determine the pair-wise interaction strength, the latter is different in each case. For the identical kaon cases, in which pair-wise quantum statistical correlations are present, the interactions are the following: $K^\pm K^\pm$–Coulomb interaction, and $K_S^0 K_S^0$–strong FSI through the $f_0(980)/a_0(980)$ resonances. For the $K_S^0 K_S^\pm$ pairs, there are no quantum statistical correlations and the only interaction present is the strong FSI through the $a_0(980)$ resonance.

$K_S^0 K_S^\pm$ femtoscopy should thus be sensitive to the properties of the $a_0(980)$ resonance. It has been suggested in many papers in the literature that the $a_0(980)$ could be a four-quark or tetraquark state [11]. It was first proposed in 1977 that experimentally-observed low-lying mesons, such as the $a_0(980)$ and $K_0^*(700)$, are part of a SU(3) tetraquark nonet using the MIT Bag model [12], which was later followed up with lattice QCD calculations [13]. There have been a number of QCD studies of these mesons that can be categorized as QCD-inspired models, see for example Refs. [11,14–16], and lattice QCD calculations, see for example Refs. [17–19].

Indeed, the results of the ALICE $K_S^0 K_S^\pm$ studies mentioned above suggested that the $a_0(980)$ is a tetraquark state. This suggestion is based on comparing the extracted pair-wise interaction strength of $K_S^0 K_S^\pm$ between pp and Pb–Pb collisions as well as with the $K_S^0 K_S^0$ studies [4,6,7,9,10].

<footnote>* E-mail address: alice-publications@cern.ch.</footnote>
From a geometric picture, since a tetraquark version of the $a_0(980)$ con-
tains a strange – anti-strange quark pair, a FSI through it should be
suppressed for a small system as in pp collisions due to an increased
annihilation probability, whereas for a large Pb–Pb collision this sup-
pression should not be present. Thus, a strong FSI would be expected
from Pb–Pb collisions and weak FSI from pp collisions, and this is what
was observed in experiments. It would also be expected that a strong
pair-wise correlation would be seen for $K_S^0K_S^0$ studies since quantum
statistics is dominant over FSI effects. This exception is corroborated
by experimental findings [4,6,7].

The success of the ALICE $K_S^0K_\pm$ studies on the nature of the $a_0(980)$ resonance motivated the first femtoscopic study ever of $\pi^\pm K_S^0$ correlations in $\sqrt{s} = 13$ TeV pp collisions. Another resonance that is a tetraquark candidate is the $K_0^*(700)$ that decays with a branching ratio of $\sim 100\%$ into $\pi K$ pairs [12]. The $K_0^*(700)$ is listed in the Review of Particle Physics [20] as a strange meson with spin 0 and isospin $\frac{1}{2}$, the quark content of the $K_0^*(700)^+$ state being $u\bar{s}$. Its mass is listed as $845 \pm 17$ MeV/c$^2$ and it is a very broad resonance with Breit-Wigner width of $468 \pm 30$ MeV/c$^2$. The mass of the $K_0^*(700)$ is above the $\pi^\pm K_S^0$ threshold, that is of about 637.18 MeV/c$^2$, and its width is seen to encompass this threshold and below. The tetraquark version of the $K_0^*(700)^+$ would have quark content $u\bar{s}dd$ and would decay by direct quark transfer into a $\pi^+K^0$ pair [12]. Thus by measuring $\pi^\pm K_S^0$ correlations it should be possible to study the quark nature of the $K_0^*(700)$ using similar methods as mentioned above for the $a_0(980)$ studies, i.e. measuring the strength of the FSI, assuming that the $\pi^\pm K_S^0$ FSI goes solely through the $K_0^*(700)$. This scenario will be studied by extracting the mass and width parameters of the FSI and comparing them with previous measurements of the $K_0^*(700)$ [21]. In the present Letter, a study of femtoscopic correlations with the non-identical pair combination $\pi^\pm K_S^0$ in pp collisions at $\sqrt{s} = 13$ TeV is presented for the first time to study the nature of the $K_0^*(700)$ resonance. The choice of using pp collisions for this work responds to the necessity of studying the FSI in a small system in which the strength of the FSI is expected to be more sensitive to the system size and thus to the quark nature of the resonance [7]. Due to the short-range nature of the strong interaction which might produce the resonant state, measurements in pp collisions are more suited since interparticle distances of a few fm are obtained [8]. Moreover, it has already been observed that the presence of resonances in the correlation function is enhanced for measurements in small colliding systems, since the signal-to-background for the considered state scales as $1/multiplicity$ [8].

The results presented in this Letter are obtained using data collected
by the ALICE Collaboration [22,23] during the 2015–2018 pp LHC run.
The Letter is organized into seven sections: Introduction, Data Analysis,
Correlation Function, Fitting, Systematic uncertainties, Results and Dis-
cussion, and Summary. The Data Analysis section gives details on how
the data were taken and how the $\pi^\pm$ and $K_S^0$ were reconstructed and
identified. The Correlation Function section describes how the $\pi^\pm K_S^0$
pairs were used to construct the correlation functions for this analy-
sis. The Fitting section describes the model used to fit the correlation
functions in order to extract the source parameters and FSI parame-
ters. The Systematic uncertainties section discusses how the system-
atic uncertainties were calculated. The Results and Discussion section
presents the results for the extracted parameters and discusses their in-
terpretation. The Summary section summarizes the results of the present
work.

## 2. Data analysis

The ALICE detector and its performance are described in detail in Refs. [22,24]. Collision events are selected by using the information from the V0 detectors composed of the VOC and V0A scintillator arrays [25,26], located on both sides of the interaction point, covering the pseudorapidity intervals $-3.7 < \eta < -1.6$ and $2.8 < \eta < 5.1$, respectively.

In the analysis $5 \times 10^8$ minimum bias triggered pp collisions at $\sqrt{s} = 13$ TeV were used. Charged particle multiplicity classes, given in terms of multiplicity percentile intervals of the visible inelastic pp cross section, were also determined from the V0 detectors [27].

The Time Projection Chamber (TPC) [28] and the Inner Tracking System (ITS) [22] were used for charged particle tracking. These detectors cover the pseudorapidity range of $|\eta| < 0.9$ and are located within a solenoid magnet with a field strength of magnitude $B = 0.5$ T. The momentum (p) determination for charged tracks was made using only the TPC space points. The ITS provided excellent spatial resolution in determining the primary collision vertex. This vertex was used to constrain the tracks reconstructed with the TPC, requiring it to be within $\pm 10$ of the center of the ALICE detector. The average momentum resolution typically obtained in this analysis for charged tracks was less than 10 MeV/c [24]. The selections based on the quality of track fitting [24,28,29], in addition to the standard track quality criteria [24], were used to ensure that only well-reconstructed tracks were taken into account in the analysis. The quality of the track was determined by the $\chi^2/N$ value for the Kalman fit to the particle trajectory in the TPC, where N is the number of TPC clusters attached to the track [24]. The track was rejected if the value was larger than 4.0.

Analysis specific event selection criteria were also applied. The event must have one accepted possible $\pi^\pm K_S^0$ pair. To reduce the effects of mini-jets which tend to produce non-flat structures in the two-particle correlation functions used in femtoscopy [30], a selection on the event transverse sphericity, calculated from the azimuthal distribution of tracks, was applied by requiring $S_T > 0.7$. $S_T$ is a scalar quantity that takes values in the range $0-1$ characterizing the event shape, i.e. $S_T \sim 0$ values represent elongated events that are “jet-like” and result from a single hard-scattering of partons, whereas $S_T \sim 1$ values represent spherical “non-jet-like” events resulting from many soft parton scatterings or several hard parton scatterings. See Ref. [30] for more details. Note that the $S_T > 0.7$ selection is estimated to have < 10% effect on the multiplicity of tracks entering the femtoscopy analysis since this selection tends to remove single hard-scattering events. Pile-up events were rejected using the timing information from the V0 (for out of bunch pile-up) and multiple reconstructed vertices from tracks (or track segments in the Silicon Pixel Detector layers of the ITS) [29,30]. The possible effect due to remaining pile-up events passing the event selection criteria described above was investigated by performing the analysis using only low interaction-rate data-taking periods. No significant difference was found in the results of the analysis compared with the higher interaction-rate runs used. Both sets of runs were combined for the present analysis.

Charged particles were identified with the central barrel detectors. Particle Identification (PID) for reconstructed tracks was carried out using both the TPC and Time-Of-Flight (TOF) detectors. For the TPC, the specific ionization energy loss $dE/dx$ was measured, and for the TOF, the flight time of the particle in the pseudorapidity range $|\eta| < 0.9$ was measured [29,31]. For the PID signal, a value ($N_\eta$) was assigned to each track denoting the number of standard deviations between the measured PID signal and the expected values, assuming a mass hypothesis, divided by the detector resolution for both detectors [6,24,29,31]. A parametrized Bethe-Bloch formula [24] was used for the TPC PID to calculate the expected energy loss $\langle dE/dx \rangle$ in the detector for a particle with a given charge, mass, and momentum. The particle mass was used to calculate the expected time-of-flight as a function of track length and momentum for the TOF PID. The detailed description of the particle identification methods is given in Ref. [32].

For Monte Carlo (MC) calculations, particles from pp collisions simulated by the general-purpose generator PYTHIA8 [33] with the Monash 2013 tune [34] were transported through a GEANT3 [35] model of the ALICE detector. The total number of simulated pp collisions used in this analysis is $5 \times 10^8$.
<table><caption>**Table 1**
π± and K_S^0 selection criteria.</caption><thead><tr><th></th><th>Value</th></tr></thead><tbody><tr><td><strong>Neutral kaon selection</strong></td><td></td></tr><tr><td>Daughter p<sub>T</sub></td><td>&gt; 0.15 GeV/c</td></tr><tr><td>Daughter |η|</td><td>&lt; 0.8</td></tr><tr><td>Daughter DCA (3D) to primary vertex</td><td>&gt; 0.4 cm</td></tr><tr><td>Daughter TPC PID [N<sub>π</sub>]</td><td>&lt; 3</td></tr><tr><td>Daughter TOF PID [N<sub>π</sub>] (for p &gt; 0.8 GeV/c)</td><td>&lt; 3</td></tr><tr><td>Kalman fit χ<sup>2</sup>/N</td><td>≤ 4</td></tr><tr><td>|η|</td><td>&lt; 0.8</td></tr><tr><td>DCA (3D) between daughters</td><td>&lt; 0.3 cm</td></tr><tr><td>DCA (3D) to primary vertex</td><td>&lt; 0.3 cm</td></tr><tr><td>Decay length (3D, lab frame)</td><td>&lt; 30 cm</td></tr><tr><td>Decay radius (2D, lab frame)</td><td>&gt; 0.2 cm</td></tr><tr><td>Cosine of pointing angle</td><td>&gt; 0.99</td></tr><tr><td>Invariant mass</td><td>0.485 &lt; m &lt; 0.510 GeV/c<sup>2</sup></td></tr><tr><td><strong>Primary pion selection</strong></td><td></td></tr><tr><td>p<sub>T</sub></td><td>0.15 &lt; p<sub>T</sub> &lt; 1.2 GeV/c</td></tr><tr><td>|η|</td><td>&lt; 0.8</td></tr><tr><td>Transverse DCA to primary vertex</td><td>&lt; 2.4 cm</td></tr><tr><td>Longitudinal DCA to primary vertex</td><td>&lt; 3.0 cm</td></tr><tr><td>TOF PID [N<sub>π</sub>] with valid TOF signal and p &gt; 0.5 GeV/c</td><td>&lt; 2</td></tr><tr><td>TPC PID [N<sub>π</sub>] if no TOF signal for all p</td><td>&lt; 2</td></tr><tr><td>Kalman fit χ<sup>2</sup>/N</td><td>≤ 4</td></tr></tbody></table>

The methods used to select and identify individual $K_S^0$ and $\pi^\pm$ particles are similar to those used for the ALICE $K^\pm K_S^0$ analysis in pp collisions at $\sqrt{s} = 13$ TeV [7].

$K_S^0$ are reconstructed from their decay into $\pi^+\pi^-$, which has a branching ratio of 69% [20]. The neutral $K_S^0$ decay vertices and parameters are reconstructed and calculated from pairs of detected $\pi^+\pi^-$ tracks, and selected based on their invariant mass and the $K_S^0$ decay topology. The selection criteria for the $K_S^0$ and the daughter pions are shown in Table 1.

The selection criteria are based on decay topology, i.e. distance-of-closest-approach (DCA) between charged pion daughters, DCA of daughter pion to the primary vertex, DCA of reconstructed $K_S^0$ to the primary vertex, cosine of pointing angle, and decay length of $K_S^0$, and were tuned to optimize purity and statistical significance. If two reconstructed $K_S^0$ particles share a daughter track, both are removed from the analysis. The MC samples were used to study any bias that might be induced by this procedure, which resulted in rejecting < 1% of the $K_S^0$ candidates [6,7]. Reconstructed $K_S^0$ candidates within invariant mass range $0.485 < m(\pi^+\pi^-) < 0.510$ GeV/c$^2$ are used in this analysis which gives $98 \pm 1\%$ purity of $K_S^0$. The purity here is defined as signal/(signal + background). The signal and background counts are calculated by fitting a fourth-order polynomial to the side-bands of the signal region to estimate the background there and subtracting this from the invariant mass histogram. A Gaussian is used to fit the signal peak in the invariant mass distribution (see Fig. 2 of Ref. [6]).

Primary charged pions are selected using the PID information from the TPC and TOF detectors. The TPC is used for PID in the full momentum range, except if a valid TOF signal is available for $p > 0.5$ GeV/c then TOF PID is used. For more details, refer to Refs. [5,6]. Table 1 summarizes the criteria used for the charged pion selection. The average charged pion purity is found using MC simulations to be $98.1 \pm 0.1\%$, in agreement with the charged pion purity reported in Ref. [6].

Two-track effects, such as the merging of two real tracks into one reconstructed track and the splitting of one real track into two reconstructed tracks, are an important challenge for femtoscopic studies. A selection on the minimum separation distance between the primary pion and a daughter pion from the decay of the $K_S^0$ in the $\pi^\pm K_S^0$ pair was made from the corresponding TPC tracks using the same method as described in Ref. [7]. The distance between the two tracks was calculated in differ-

ent positions along their trajectory in the TPC (at radial distances from 85 to 150 cm from the interaction point) and a minimum separation distance of 20 cm was required.

### 3. Measurement of correlation functions

The momentum correlations of $\pi^\pm K_S^0$ pairs using the two-particle correlation function are studied in this analysis. The correlation function is defined as $C(k^*) = A(k^*)/B(k^*)$, where $A(k^*)$ is the measured distribution of pairs from the same event and $B(k^*)$ is the reference distribution of pairs from mixed events. The denominator $B(k^*)$ is formed by mixing particles from one event with particles from 10 different events that satisfy the conditions that the primary vertex positions along the beam direction are within 2 cm of each other, and have similar multiplicity, i.e. events within 2% difference in multiplicity percentile are mixed. Other sizes of the mixed events buffer were also investigated with no significant effect on the results of this work. All events used are required to satisfy the $S_T > 0.7$ selection. The $k^*$ is the magnitude of the momentum of each of the particles in the pair rest frame. In the present case of unequal mass particles in the pair, $m_1$ and $m_2$, $k^*$ is given by

$$k^* = \sqrt{\frac{a^2 - m_1^2 m_2^2}{2a + m_1^2 + m_2^2}} \quad (1)$$

where,

$$a = (q_{\text{inv}}^2 + m_1^2 + m_2^2)/2. \quad (2)$$

For convenience, the square of the invariant momentum difference $q_{\text{inv}}^2 = |\vec{p}_1 - \vec{p}_2|^2 - |E_1 - E_2|^2$ is evaluated with the momenta and energies of the two particles measured in the laboratory frame. In the case where $m_1 = m_2$, $k^*$ can be expressed as $k^* = q_{\text{inv}}/2$. A $k^*$ bin size of 20 MeV/c was used in the analyses presented in this Letter.

Correlation functions are analyzed for three cases: 1) 0–100% multiplicity class and $k_T > 0$ GeV/c, 2) 0–100% multiplicity class and $k_T < 0.5$ GeV/c, and 3) 0–5% multiplicity class and $k_T < 0.5$ GeV/c, where $k_T = |\vec{p}_{T1} + \vec{p}_{T2}|/2$, and where $\vec{p}_{T1}$ and $\vec{p}_{T2}$ are the transverse momenta of the particles in the pair. The three cases correspond to the following average $k_T$ and average charged-particle pseudorapidity density ($\langle dN/d\eta \rangle$ in the $|\eta| < 0.8$ range) values [27]: 1) $\langle k_T \rangle = 0.655$ GeV/c, $\langle dN/d\eta \rangle = 6.89$, 2) $\langle k_T \rangle = 0.323$ GeV/c, $\langle dN/d\eta \rangle = 6.89$, and 3) $\langle k_T \rangle = 0.326$ GeV/c, $\langle dN/d\eta \rangle = 21.2$. The purpose of analyzing these
<figure><img src="image_3.png" /><figcaption>Fig. 1. Top row: $\pi^{\pm}K_S^0$ correlation functions experimentally measured (blue dots) compared with PYTHIA8+GEANT3 simulations (red squares) obtained in pp collisions at $\sqrt{s} = 13$ TeV for 0–100% multiplicity class and $k_T > 0$ (left), 0–100% multiplicity class and $k_T < 0.5$ GeV/c (center), and 0–5% multiplicity class and $k_T < 0.5$ GeV/c (right). The PYTHIA8+GEANT3 correlation function is normalized to the data at $k^* = 0.5$ GeV/c. Bottom row: Ratio of Data to PYTHIA8+GEANT3 simulations for the three studied cases. Statistical uncertainties are represented by bars.</figcaption></figure>

cases is to obtain different femtoscopic source sizes and to study the effect of source size on the FSI. It has been found from femtoscopy measurements in pp collisions that the source size depends on both $\langle k_T \rangle$ and $\langle dN/d\eta \rangle$ [4,36]. In addition, case 1) was chosen to maximize the sample size and to provide a selection-free case to compare with the other cases having multiplicity and $k_T$ selections.

Monte Carlo simulations were used to simulate correlation functions which were compared with experimental data. Fig. 1 shows in the top row the correlation functions experimentally measured (blue) along with the simulated ones (red). The MC correlation functions are normalized to the experimental ones at $k^* = 0.5$ GeV/c for the three cases mentioned above. The single-event and mixed-event distributions of the correlation functions are summed over $\pi^+K_S^0$ and $\pi^-K_S^0$ pairs, since it is found that there is no significant difference between the $\pi^+K_S^0$ and $\pi^-K_S^0$ corresponding correlation functions. The decay of the $K^*(892)$ meson is clearly seen at $k^* \sim 0.3$ GeV/c for all cases. For $k^* > 0.35$ GeV/c a non-flat baseline is also observed in all cases. This non-flat baseline is associated with soft parton fragmentation, or mini-jets, that are not completely suppressed by the transverse sphericity selection [36–38], as well as the presence of momentum conservation effects. Non-flat baselines in two-particle correlation functions obtained in pp collisions are often observed [9,36,37]. In particular, measured correlation functions show a decreasing dependence of the baseline with increasing $k^*$ for low multiplicity classes, and a reversal of this dependence for higher multiplicity classes, as seen in Fig. 1. This effect in the data is seen to be present as well in the PYTHIA8 simulations. The simulations well reproduce the $K^*(892)$ peak and the background visible at larger $k^*$, hence in order to remove these two contributions, the measured correlation function is subsequently divided by the simulated one, defined as $C'(k^*)$, as shown in the bottom panels of Fig. 1. The statistical uncertainty from the MC correlation function is propagated with the uncertainty from the experimental one in the ratio, which becomes the final correlation function.

Finite track momentum resolution can smear the relative momentum correlation functions used in this analysis. This effect is corrected using MC simulations as done in previous works [22,23]. It is found that the effect of the momentum resolution correction is small for the very lowest $k^*$ bin with the largest statistical error bars and negligible

for the rest of the bins, resulting in a < 3% effect on the extracted fit parameters.

## 4. Fitting

The momentum resolution corrected ratio of the experimental $\pi^{\pm}K_S^0$ correlation function to the MC correlation function was fitted by a model in order to extract information on the size of the source, as well as the strength and nature of the FSI between the particles in the pair. The fit function is given by,

$$C'(k^*) = \kappa \left[ C_{\text{Lednicky}}(k^*) + \epsilon \frac{d N_{\text{BW}}}{dm} \frac{dm}{dk^*} \right] \quad (3)$$

where,

$$\frac{d N_{\text{BW}}}{dm} \propto \frac{\Gamma_{892}}{(m - m_{892})^2 + \Gamma_{892}^2/4} \quad (4)$$

is the Breit–Wigner resonance distribution. This last term fits out any residual presence of the $K^*(892)$ peak (see below).

The quantities $\epsilon$ and $\kappa$, where $\epsilon$ is the magnitude of a correction term on the MC modeling of the $K^*(892)$ (see below) and $\kappa$ is an overall normalization factor, are fit parameters, and $\Gamma_{892}$ and $m_{892}$ are the full-width at half maximum (FWHM) and mass of the $K^*(892)$, respectively, taken from the Review of Particle Physics [20]. The first term in Eq. (3) is a modified version of the Lednicky parametrization [2,39,40] which assumes that the pair interaction is due to strong final-state interaction of a near-threshold resonance. The second term in Eq. (3) is used to fit out the small residual bump in the ratio that results from a slight overcompensation of the MC in modeling the $K^*(892)$ peak in the data that can be seen in Fig. 1, located at $k^* \sim 0.3$ GeV/c. Fitting out this residual bump results in an improved $\chi^2$/ndf for all of the fits.

A Gaussian distribution of the source size in the pair reference frame is assumed in the FSI parameterization. More general forms for this distribution could be used, but using the Gaussian results in the analytic form of the Lednicky equation. Another motivation for staying with the Gaussian is to facilitate comparisons with previous published results that also used the Gaussian distribution.
<figure><img src="image_4.png" /><figcaption>Fig. 2. Example fit of Eq. (5) to the corrected correlation functions after Eq. (3) has been used to remove the PYTHIA8+GEANT3 overcompensation of the K*(892), for $\pi^{\pm}K_S^0$ from $\sqrt{s}$ = 13 TeV pp collisions for 0–100% multiplicity class and $k_T$ > 0 (left), 0–100% multiplicity class and $k_T$ < 0.5 GeV/c (center), and 0–5% multiplicity class and $k_T$ < 0.5 GeV/c (right). Statistical uncertainties are represented as bars.</figcaption></figure>

The quantity $C_{\text{Lednicky}}(k^*)$ has the form

$$C_{\text{Lednicky}}(k^*) = 1 + \left(\frac{\lambda\alpha}{2}\right) \left[ \left|\frac{f(k^*)}{R}\right|^2 + \frac{4Rf(k^*)}{\sqrt{\pi}R} F_1(2k^*R) - \frac{2If(k^*)}{R} F_2(2k^*R) + \Delta C \right] \quad (5)$$

and

$$F_1(z) = \int_0^z dx \frac{e^{x^2-z^2}}{z}; \quad F_2(z) = \frac{1-e^{-z^2}}{z}. \qquad (6)$$

$\alpha$ is the symmetry parameter and is set to 0.5 assuming symmetry in $K^0$ and $K^0$ production since the $K_S^0$ is a linear combination of these; $R$ is the radius parameter of the source; and $\lambda$ is the correlation strength. The term $f(k^*)$ is the s-wave $\pi^{\pm}K_S^0$ scattering amplitude whose FSI contribution is the near-threshold resonance. A relativistic Breit-Wigner amplitude is assumed,

$$f(k^*) = \frac{\gamma}{M_R^2 - s - i\gamma k^*}. \qquad (7)$$

In Eq. (7), $M_R$ is the mass of the resonance, and $\gamma$ is the coupling of the resonance to its decay channel, i.e. $\pi^{\pm}K_S^0$. Also, $s = (\sqrt{m_K^2 + k^*}^2 + \sqrt{m_{\pi}^2 + k^*})^2$ is the square of the energy of the pair in its rest frame. A Breit-Wigner form was chosen for $f(k^*)$ since the fitted $M_R$ and $\gamma$ to the FSI resonance from the present work will be compared with other measurements that used the Breit-Wigner form in order to identify the resonance [41,42].

The quantity $\Delta C$ is a correction to the derivation of Eq. (5), that assumes spherical outgoing waves, to account for the true scattered waves in the inner region of the short-range potential [2,7], and is given by,

$$\Delta C = \frac{(2 + m_{\pi}/m_{K} + m_{K}/m_{\pi}) |f(k^*)|^2}{2\sqrt{\pi}R^3\gamma} \quad (8)$$

As a test, a p-wave term was added to the s-wave term in the scattering amplitude in deriving the Lednicky equation to study whether there was interference of the K*(892) with the s-wave FSI. It was found that the p-wave term had a negligible effect on the fits, and was thus ignored.

The fitting strategy was to make a six-parameter fit of Eq. (3) to the corrected ratio of the experimental $\pi^{\pm}K_S^0$ correlation function to the corresponding MC correlation function to extract $R$, $\lambda$, $M_R$, $\gamma$, $\epsilon$, and $\kappa$. The nominal fit range is $0 < k^* < 0.76$ GeV/c in all cases. The nominal maximum of 0.76 GeV/c of the fit range was set to give the optimal overlap between the experimental and MC correlation functions in the baseline region.

Fig. 2 shows the correlation functions and fits. The MC overcompensation of the K*(892) has been removed from the “Data/MC” points by subtracting out the second term in Eq. (3) in order to show how well

$C_{\text{Lednicky}}(k^*)$ fits the ratio, and the ratio has been divided by $\kappa$. The $\chi^2$/ndf for the fits shown in Fig. 2 are 1.6, 1.8, and 0.92, with p-values of 1.7% and 0.36% and 60%, respectively.

## 5. Systematic uncertainties

Table 2 shows the total systematic uncertainties on the $R$, $\lambda M_R$, and $\gamma$ parameters extracted from the $\pi^{\pm}K_S^0$ correlation function in pp collisions at $\sqrt{s}$ = 13 TeV.

The “fit systematic uncertainty” column reports the systematic uncertainty due to varying the $k^*$ fit range. Varying the fit range by 20% resulted in < 3% effect on the fit parameters. Fitting uncertainties were calculated including correlations among the fit parameters as done using a MINOS algorithm in order to obtain conservative estimates of the uncertainties [43].

The “selection systematic uncertainty” column reports the systematic uncertainty related to the variation of track and PID selection criteria used in the data analysis. To determine this, the single particle selection criteria shown in Table 1 were varied by ±10%, and the value chosen for the minimum separation distance of same-sign tracks was varied by ±20% [7]. The systematic uncertainty related to the sphericity selection of $S_T$ > 0.7 is also included in this source of systematic uncertainty, where $S_T$ was varied by ±10% from its nominal selection value. The uncertainty was estimated from the variation of the results with respect to those obtained with the nominal selections. The resulting relative systematic uncertainties are of about 10% for $\lambda$, about 5% for $R$, and about 2% for the other parameters.

The “total systematic uncertainty” column is obtained as the sum in quadrature of the contribution of the two sources described above. The “total uncertainty” column is the sum in quadrature of the statistical uncertainty and the total systematic uncertainty. As seen, the total systematic uncertainties tend to be greater than or comparable to the statistical uncertainties. Table 3 shows an approximate breakdown of the relative systematic uncertainties (in percentage) from the different variations considered. See Table 1 in Section 2 for the nominal values of the selection criteria. Note that “min. sep. var.” refers to the variation of the selection for minimum separation between $K_S^0$ daughter and primary pions in the TPC, mentioned earlier, and “$m(\pi^+\pi^-)$” and primary vertex variations” refer to the combined effect of varying the invariant mass selection for $K_S^0$ and varying the selection for the primary vertex of the event. As seen, in general the variations have the largest effect on $\lambda$ and the smallest effect on $M_R$ and $\gamma$, with the $S_T$ variation having the largest single-variation effect on all of the parameters.

## 6. Results and discussion

The $R$, $\lambda$, $M_R$, and $\gamma$ parameters extracted from the present analysis of $\pi^{\pm}K_S^0$ correlation functions in pp collisions at $\sqrt{s}$ = 13 TeV are reported in Table 2 for the three cases mentioned above. The $\lambda$ parame-
<caption>**Table 2**</caption>

Fit results for $R, \lambda, M_R$, and $\gamma$ showing statistical and systematic uncertainties from the present analysis. Uncertainties are symmetric unless specified otherwise. See the text for the description of the various sources of uncertainties.

<table><caption>**Table 3**</caption><thead><tr><th>R, λ, M<sub>R</sub>, or γ</th><th>fit value</th><th>statistical uncertainty</th><th>fit systematic uncertainty</th><th>selection systematic uncertainty</th><th>total systematic uncertainty</th><th>total uncertainty</th></tr></thead><tbody><tr><td colspan="7">0-100% multiplicity class k<sub>T</sub> > 0</td></tr><tr><td>R (fm)</td><td>0.912</td><td>0.037</td><td>0.011</td><td>0.053</td><td>0.054</td><td>0.065</td></tr><tr><td>λ</td><td>0.0783</td><td>+0.0096</td><td>0.0032</td><td>0.0078</td><td>0.0084</td><td>+0.0127</td></tr><tr><td></td><td></td><td>-0.0086</td><td></td><td></td><td></td><td>-0.0121</td></tr><tr><td>M<sub>R</sub> (GeV/c<sup>2</sup>)</td><td>0.833</td><td>0.002</td><td>0.006</td><td>0.013</td><td>0.015</td><td>0.015</td></tr><tr><td>γ (GeV)</td><td>0.890</td><td>0.015</td><td>0.012</td><td>0.016</td><td>0.020</td><td>0.025</td></tr><tr><td colspan="7">0-100% multiplicity class k<sub>T</sub> < 0.5 GeV/c</td></tr><tr><td>R (fm)</td><td>1.063</td><td>0.058</td><td>0.015</td><td>0.064</td><td>0.066</td><td>0.088</td></tr><tr><td>λ</td><td>0.111</td><td>0.017</td><td>0.004</td><td>0.013</td><td>0.014</td><td>0.022</td></tr><tr><td>M<sub>R</sub> (GeV/c<sup>2</sup>)</td><td>0.804</td><td>0.003</td><td>0.005</td><td>0.013</td><td>0.014</td><td>0.014</td></tr><tr><td>γ (GeV)</td><td>0.801</td><td>0.023</td><td>0.020</td><td>0.014</td><td>0.024</td><td>0.033</td></tr><tr><td colspan="7">0-5% multiplicity class k<sub>T</sub> < 0.5 GeV/c</td></tr><tr><td>R (fm)</td><td>1.618</td><td>+0.136</td><td>0.015</td><td>0.089</td><td>0.090</td><td>+0.163</td></tr><tr><td></td><td></td><td>-0.109</td><td></td><td></td><td></td><td>-0.142</td></tr><tr><td>λ</td><td>0.274</td><td>+0.077</td><td>0.001</td><td>0.026</td><td>0.026</td><td>+0.081</td></tr><tr><td></td><td></td><td>-0.053</td><td></td><td></td><td></td><td>-0.059</td></tr><tr><td>M<sub>R</sub> (GeV/c<sup>2</sup>)</td><td>0.765</td><td>0.004</td><td>0.002</td><td>0.012</td><td>0.013</td><td>0.013</td></tr><tr><td>γ (GeV)</td><td>0.714</td><td>+0.042</td><td>0.005</td><td>0.013</td><td>0.014</td><td>+0.044</td></tr><tr><td></td><td></td><td>-0.037</td><td></td><td></td><td></td><td>-0.039</td></tr></tbody></table>

Breakdown of the relative systematic uncertainties for $R, \lambda, M_R$, and $\gamma$ from the variation of track, PID and mixed-event selection criteria. The %Δ row is the percentage that the quantity was changed. See the text for the description of the various uncertainties.

<table><thead><tr><th>Quantity changed</th><th>Fit range</th><th>Min. sep. var.</th><th>TOF, TPC N<sub>σ</sub></th><th>DCA var.</th><th>m(π<sup>+</sup>π<sup>-</sup>) and primary vertex var.</th><th>Multiplicity difference for event mixing</th><th>Decay length</th><th>S<sub>T</sub> var.</th></tr></thead><tbody><tr><td>%Δ</td><td>20</td><td>20</td><td>10</td><td>10</td><td>10</td><td>10</td><td>10</td><td>10</td></tr><tr><td>%R</td><td>1</td><td>1</td><td>2</td><td>2</td><td>1</td><td>1</td><td>1</td><td>3</td></tr><tr><td>%λ</td><td>3</td><td>5</td><td>3</td><td>3</td><td>3</td><td>2</td><td>2</td><td>5</td></tr><tr><td>%M<sub>R</sub></td><td>1</td><td>&lt; 1</td><td>&lt; 1</td><td>&lt; 1</td><td>&lt; 1</td><td>&lt; 1</td><td>&lt; 1</td><td>2</td></tr><tr><td>%γ</td><td>2</td><td>1</td><td>&lt; 1</td><td>&lt; 1</td><td>&lt; 1</td><td>&lt; 1</td><td>&lt; 1</td><td>2</td></tr></tbody></table>

ters are corrected for purity by dividing the extracted $\lambda$ values with the product of the $\pi^{\pm}$ and $K_S^0$ purities (see Section 2).

Since the main goal of this measurement is to study the $K_0^*(700)$ resonance, one must first establish that the FSI of the $\pi^{\pm}K_S^0$ pair occurs indeed through this resonance. This can be done by comparing the measured $M_R$ and $\gamma$ parameters extracted from this analysis with previously measured values of $M_R$ and $\Gamma_R$ for the $K_0^*(700)$ [41,42], where $\Gamma_R$ is the FWHM of the relativistic Breit-Wigner resonance distribution, whose amplitude is expressed as [44],

$$f(s) \sim \frac{1}{M_R^2 - s - i M_R \Gamma_R} \qquad (9)$$

Comparing this denominator with the denominator of Eq. (7), one can obtain an estimate for $\Gamma_R$ from the present results,

$$\Gamma_R = \frac{\langle k^* \rangle \gamma}{M_R}, \qquad (10)$$

where $\langle k^* \rangle$ is the average of $k^*$ determined by weighting $k^*$ by the experimental $dN/dk^*$ distribution over the fit range used in fitting Eq. (3) to the correlation function. Table 4 lists the values of $\Gamma_R$ extracted from the present work using Eq. (10) for the three cases studied. The uncertainties shown for $\langle k^* \rangle$ are estimated by considering different $k^*$ ranges

<caption>**Table 4**</caption>

The $\langle k^* \rangle$ and corresponding $\Gamma_R$ extracted from the three cases measured in the present work using Eq. (10).

<table><thead><tr><th>Case</th><th>⟨k*⟩ (GeV/c)</th><th>Γ<sub>R</sub> (GeV/c<sup>2</sup>)</th></tr></thead><tbody><tr><td>0-100% multiplicity class, k<sub>T</sub> > 0</td><td>0.403<sup>+0.093</sup><sub>-0.056</sub></td><td>0.430<sup>+0.088</sup><sub>-0.053</sub></td></tr><tr><td>0-100% multiplicity class, k<sub>T</sub> < 0.5 GeV/c</td><td>0.408<sup>+0.060</sup><sub>-0.050</sub></td><td>0.406<sup>+0.050</sup><sub>-0.042</sub></td></tr><tr><td>0-5% multiplicity class, k<sub>T</sub> < 0.5 GeV/c</td><td>0.418<sup>+0.072</sup><sub>-0.053</sub></td><td>0.390<sup>+0.068</sup><sub>-0.051</sub></td></tr></tbody></table>

for calculating the average, namely $0 < k^* < 0.6$ GeV/c and $0 < k^* < 2$ GeV/c, and taking the differences from the nominal $\langle k^* \rangle$ to obtain conservative estimates of the uncertainties.

Fig. 3 compares the values of $M_R$ and $\Gamma_R$ extracted in the present work with measurements of these quantities for the $K_0^*(700)$ from the BES [41] and E791 Collaborations [42]. The BES Collaboration measured the relativistic Breit-Wigner parameters of the $K_0^*(700)$ through the decay of the $J/\psi$ meson, whereas the E791 Collaboration measured them through the decay of the $D^+$ meson. The total uncertainties defined as the quadratic sum of the statistical and systematic uncertainties are shown on the points for all cases. As seen, the values reported in this work agree within uncertainties with the $K_0^*(700)$ Breit-Wigner param-
<figure><img src="image_5.png" /><figcaption>Fig. 3. The extracted Breit–Wigner parameters from the $\pi^{\pm}K_S^0$ femtoscopic correlation in pp collisions at $\sqrt{s} = 13$ TeV compared with those for $K_0^*(700)$ from the BES [41] and the E791 [42] experiments. The horizontal and vertical bars represent the total uncertainties. The “ALICE average” value is the weighted average of the three ALICE points.</figcaption></figure>

<figure><img src="image_6.png" /><figcaption>Fig. 4. The $\lambda$ parameter as a function of source size $R$ extracted from the $\pi^{\pm}K_S^0$ femtoscopy measurement in pp collisions at $\sqrt{s} = 13$ TeV. Results are compared with the previous ALICE measurements, obtained from $K_S^0K_S^0$ [6,7] and $\pi\pi$ [36] femtoscopy studies in pp and Pb–Pb collisions and the calculations from a toy geometric model (see text). The model calculations for the tetraquark and diquark hypotheses for the $K_0^*(700)$ are shown as black and light green dashed lines, respectively, the short dashed lines representing the Gaussian $\rho(r)$ and the long dashed lines representing the exponential $\rho(r)$.</figcaption></figure>

eters measured in the other two experiments. It is seen that the present results have smaller uncertainties than the previous measurements. It is also seen that although the three $\Gamma_R$ values from the present work agree within uncertainties, the differences among the three $M_R$ values are outside of their uncertainties. This could be a consequence of using the Breit–Wigner function to fit a resonance where the condition $\Gamma_R \ll M_R$ is not fulfilled, which can lead to kinematic dependences on the extracted $M_R$ and $\Gamma_R$ [20,44]. However, these differences in $M_R$ are small compared with the extracted $M_R$ values, and thus it is judged that these results strongly support the assumption that the resonance responsible for the FSI of the $\pi^{\pm}K_S^0$ pairs studied in the present work is the $K_0^*(700)$ resonance.

The extracted $R$ and $\lambda$ parameters shown in Table 2 can be used to obtain information about the quark configuration of the $K_0^*(700)$. Fig. 4 compares the values of $R$ and $\lambda$ extracted in the present work with published results for these parameters from ALICE measurements in pp and Pb–Pb collisions in which $\pi\pi$ and $K_S^0K_S^0$ pairs were analyzed [4,6,7,36]. The $\pi^{\pm}K_S^0$ results are shown with separate statistical (error bars) and systematic (boxes) uncertainties, whereas for the previous results, the error bars represent the combination of the statistical and systematic uncertainties. For the $\pi\pi$ femtoscopic measurements in pp collisions at $\sqrt{s} = 7$ TeV reported in [36] with average $k_T$ values of ~0.15 and ~0.35 GeV/c, the $\lambda$ values are given as varying in the range 0.42–0.55, so $\lambda$

is plotted as the center of this range with uncertainties extending to the upper and lower limits of the range.

For the $R$ parameter, the values from the present $\pi^{\pm}K_S^0$ analysis are comparable with the published $\pi\pi$ and $K_S^0K_S^0$ measurements in pp collisions, i.e. in the range 1–2 fm, as would be expected from pp collisions where the source size is ~1 fm. For the $\lambda$ parameter, whereas the results from $\pi\pi$ and $K_S^0K_S^0$ are compatible with values of about 0.5 or greater, for the present $\pi^{\pm}K_S^0$ analysis significantly lower values are obtained, ranging from about 0.05 to about 0.25 depending on $R$. The expectation is that $\lambda$ would be the same for $\pi^{\pm}K_S^0$ as for the identical-meson measurements. The $\lambda$ value of ~0.5 has been shown to be due to the presence of long-lived resonances whose decay into the detected mesons impacts the measurement of the “direct” mesons coming from the source of interest [7,45]. Another significant difference between the present $\pi^{\pm}K_S^0$ results and the $\pi\pi$ and $K_S^0K_S^0$ results is that $\lambda$ has a strong $R$ dependence for the former, whereas there is no significant dependence of $\lambda$ on $R$ for the latter, i.e. even extending $R$ to the value from Pb–Pb collisions shows no significant effect on $\lambda$.

As discussed in Refs. [7] and [9], a physics effect that could cause this difference in $\lambda$ values for $\pi^{\pm}K_S^0$ pairs is related to the possibility that the $K_0^*(700)$ resonance, that is assumed to be solely responsible for the FSI in the $\pi^{\pm}K_S^0$ pair, is actually a tetraquark state of the form $(q_1, \bar{q}_2, q_3, \bar{q}_3)$, in which $q_1, q_2$ and $q_3$ indicate the flavor of the valence quarks of the $\pi$ and $K_S^0$. In particular, $q_1$ and $q_2$ can be a u or s quark, while $q_3$ is a d quark. For example, the quark content of a tetraquark $K_0^*(700)^+$ would be $u\bar{s}d\bar{d}$, whereas the diquark version would be $u\bar{s}$. The strength of the FSI through a tetraquark $K_0^*(700)^+$ could be decreased by the small source size of the $\pi^{\pm}K_S^0$ source, i.e. at $R \sim 1$ fm as is measured in these collisions. This could occur since $d\bar{d}$ annihilation would be enhanced due to the proximity of the $\pi^{\pm}$ and $K_S^0$ at their creation, which would open up a non-resonant channel in the scattering process that would be reflected by reducing $\lambda$. For a FSI through a diquark $K_0^*(700)^+$, with the form $u\bar{s}$, the small source geometry should not reduce its strength. For the $K_S^0K_S^0$ and $\pi\pi$ cases, $\lambda$ should not be affected by the source size since the pair correlation is dominated by the effect of quantum statistics, for which in the ideal case $\lambda$ does not depend on $R$, and which is found to be much stronger than the strong FSI present for these identical particle pairs [2].

In order to demonstrate the $R$ dependence of $\lambda$ for a tetraquark or a diquark $K_0^*(700)$ based on the geometric considerations discussed above, a simple toy model is constructed, taking the form of the $\lambda$ factor for a tetraquark state,

$$ \lambda = \lambda_0(1 - aP) \quad (11) $$

and for a diquark,

$$ \lambda = \lambda_0 a P \quad (12) $$

where,

$$ P \equiv \frac{\int \rho(r) \rho(|\vec{r} - \vec{R}|) dV}{\int |\rho(r)|^2 dV} \quad (13) $$

can be considered the “overlap probability” between the $\pi$ and $K_S^0$ in the pair as they are emitted from the pp collision. The quantity $\rho(r)$ is the meson volume distribution, assumed to be the same for the $\pi$ and $K_S^0$, $\lambda_0$ is the maximum value for $\lambda$, and $a$ is essentially the “d–d annihilation efficiency” that in principle could take any value in the range 0–1. Assuming $\rho(r) \sim e^{-r^2/(2\sigma^2)}$ or $\sim e^{-r/r_0}$, $\lambda_0 = 0.6$, the average value for $\pi\pi$ and $K_S^0K_S^0$ measurements from Refs. [36] and [6,7], and assuming 100% d–d annihilation efficiency for any non-zero overlap, $a=1$, the free parameters of the model, i.e. $\sigma$ and $r_0$, are adjusted to give a good fit to the $\pi^{\pm}K_S^0$ measurements. The results from Eqs. (11) and (12) are shown in Fig. 4, along with the results from $\pi^{\pm}K_S^0$ measurements of this work and
published ALICE measurements for $K_S^0 K_S^0$ [6,7] and $\pi\pi$ pairs [36] from pp and Pb-Pb collisions. The free model parameters are set to $\sigma = 1.1$ fm and $r_0 = 0.85$ fm for the Gaussian (short dashed lines) and exponential (long dashed lines) distributions, respectively, which are considered reasonable values since hadronic sizes are expected to be ~ 1 fm. As seen, using reasonable model parameter values, the tetraquark case, Eq. (11), describes the R dependence of $\lambda$ from the present measurements well for both the Gaussian and exponential meson shapes as being a geometric effect. The diquark case is seen to predict an R dependence that is incompatible with the measured one.

Therefore, the present results of $\pi^\pm K_S^0$ femtoscopy in pp collisions at $\sqrt{s} = 13$ TeV suggest that the $K_0^*(700)$ is a tetraquark state.

## 7. Summary

Femtoscopic correlations with the particle pair combination $\pi^\pm K_S^0$ are studied in pp collisions at $\sqrt{s} = 13$ TeV for the first time by the ALICE experiment at the LHC. Source parameters and final-state interaction parameters are extracted by fitting a model based on a Gaussian distribution of the source to the experimental two-particle correlation functions. The model used assumes that solely the final-state interaction through a resonance determines the correlations, and is defined in terms of a mass and the coupling parameter to the decay into a $\pi^\pm K_S^0$ pair. The extracted mass and width parameters of the FSI are consistent with previous measurements of the $K_0^*(700)$ resonance, and the smaller value and increasing behavior of the $\lambda$ parameter with R compared with identical boson measurements give support that the $K_0^*(700)$ is a four-quark state, i.e. a tetraquark state [19]. A simple geometric model that assumes a tetraquark FSI describes well the R dependence of $\lambda$ extracted from the measured correlation functions.

## Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

## Data availability

This manuscript has associated data in a HEPData repository at: https://www.hepdata.net/record/ins2739149.

## Acknowledgements

The ALICE Collaboration would like to thank all its engineers and technicians for their invaluable contributions to the construction of the experiment and the CERN accelerator teams for the outstanding performance of the LHC complex. The ALICE Collaboration gratefully acknowledges the resources and support provided by all Grid centres and the Worldwide LHC Computing Grid (WLCG) collaboration. The ALICE Collaboration acknowledges the following funding agencies for their support in building and running the ALICE detector: A. I. Alikhanyan National Science Laboratory (Yerevan Physics Institute) Foundation (ANSL), State Committee of Science and World Federation of Scientists (WFS), Armenia; Austrian Academy of Sciences, Austrian Science Fund (FWF): [M 2467-N36] and Nationalstiftung für Forschung, Technologie und Entwicklung, Austria; Ministry of Communications and High Technologies, National Nuclear Research Center, Azerbaijan; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Financiadora de Estudos e Projetos (Finep), Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) and Universidade Federal do Rio Grande do Sul (UFRGS), Brazil; Bulgarian Ministry of Education and Science, within the National Roadmap for Research Infrastructures 2020-2027 (object CERN), Bulgaria; Ministry of Education of China (MOEC), Ministry of Science & Technology of China (MSTC) and National Natural Science Foundation of China (NSFC), China; Ministry of Science and

Education and Croatian Science Foundation, Croatia; Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear (CEADEN), Cuba; The Ministry of Education, Youth and Sports of the Czech Republic, Czech Republic; The Danish Council for Independent Research | Natural Sciences, the Villum Fonden and Danish National Research Foundation (DNRF), Denmark; Helsinki Institute of Physics (HIP), Finland; Commissariat à l'Énergie Atomique (CEA) and Institut National de Physique Nucléaire et de Physique des Particules (IN2P3) and Centre National de la Recherche Scientifique (CNRS), France; Bundesministerium für Bildung und Forschung (BMBF) and GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany; General Secretariat for Research and Technology, Ministry of Education, Research and Religions, Greece; National Research, Development and Innovation Office, Hungary; Department of Atomic Energy, Government of India (DAE), Department of Science and Technology, Government of India (DST), University Grants Commission, Government of India (UGC) and Council of Scientific and Industrial Research (CSIR), India; National Research and Innovation Agency - BRIN, Indonesia; Istituto Nazionale di Fisica Nucleare (INFN), Italy; Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) and Japan Society for the Promotion of Science (JSPS) KAKENHI, Japan; Consejo Nacional de Ciencia (CONACYT) y Tecnología, through Fondo de Cooperación Internacional en Ciencia y Tecnología (FONCICYT) and Dirección General de Asuntos del Personal Académico (DGAPA), Mexico; Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO), Netherlands; The Research Council of Norway, Norway; Commission on Science and Technology for Sustainable Development in the South (COMSATS), Pakistan; Pontificia Universidad Católica del Perú, Peru; Ministry of Education and Science, National Science Centre and WUT ID-UB, Poland; Korea Institute of Science and Technology Information and National Research Foundation of Korea (NRF), Republic of Korea; Ministry of Education and Scientific Research, Institute of Atomic Physics, Ministry of Research and Innovation and Institute of Atomic Physics and Universitatea Nationala de Stiinta si Tehnologie Politehnia Bucuresti, Romania; Ministry of Education, Science, Research and Sport of the Slovak Republic, Slovakia; National Research Foundation of South Africa, South Africa; Swedish Research Council (VR) and Knut and Alice Wallenberg Foundation (KAW), Sweden; European Organization for Nuclear Research, Switzerland; Suranaree University of Technology (SUT), National Science and Technology Development Agency (NSTDA) and National Science, Research and Innovation Fund (NSRF via PMU-B B05F650021), Thailand; Turkish Energy, Nuclear and Mineral Research Agency (TENMAK), Turkey; National Academy of Sciences of Ukraine, Ukraine; Science and Technology Facilities Council (STFC), United Kingdom; National Science Foundation of the United States of America (NSF) and United States Department of Energy, Office of Nuclear Physics (DOE NP), United States of America. In addition, individual groups or members have received support from: Czech Science Foundation (grant no. 23-07499S), Czech Republic; European Research Council, Strong 2020 - Horizon 2020 (grant nos. 950692, 824093), European Union; ICSC - Centro Nazionale di Ricerca in High Performance Computing, Big Data and Quantum Computing, European Union - NextGenerationEU; Academy of Finland (Center of Excellence in Quark Matter) (grant nos. 346327, 346328), Finland.

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## ALICE Collaboration

S. Acharya¹²⁸, D. Adamová⁸⁷, G. Aglieri Rinella³³, L. Aglietta²⁵, M. Agnello³⁰, N. Agrawal²⁶, Z. Ahammed¹³⁶, S. Ahmad¹⁶, S.U. Ahn⁷², I. Ahuja³⁸, A. Akindinov¹⁴², M. Al-Turany⁹⁸, D. Aleksandrov¹⁴², B. Alessandro⁵⁷, H.M. Alfanda⁶, R. Alfaro Molina⁶⁸, B. Ali¹⁶, A. Alici²⁶, N. Alizadehvandchali¹¹⁷, A. Alkin³³, J. Alme²¹, G. Alocco⁵³, T. Alt⁶⁵, A.R. Altamura⁵¹, I. Altsybeev⁹⁶, J.R. Alvarado⁴⁵, M.N. Anaam⁶, C. Andrei⁴⁶, N. Andreou¹¹⁶, A. Andronic¹²⁷, E. Andronov¹⁴², V. Anguelov⁹⁵, F. Antinori⁵⁵, P. Antonioli⁵², N. Apadula⁷⁵, L. Aphecetche¹⁰⁴, H. Appelshäuser⁶⁵, C. Arata⁷⁴, S. Arcelli²⁶, M. Aresti²³, R. Arnaldi⁵⁷, J.G.M.C.A. Arneiro¹¹¹, I.C. Arsene²⁰, M. Arslandok¹³⁹, A. Augustinus³³, R. Averbeck⁹⁸, M.D. Azmi¹⁶, H. Baba¹²⁵, A. Badalà⁵⁴, J. Bae¹⁰⁵, Y.W. Baek⁴¹, X. Bai¹²¹, R. Bailhache⁶⁵, Y. Bailung⁴⁹, R. Bala⁹², A. Balbino³⁰, A. Baldisseri¹³¹, B. Balis², D. Banerjee⁴, Z. Banoo⁹², F. Barile³², L. Barioglio⁵⁷, M. Barlou⁷⁹, B. Barman⁴², G.G. Barnaföldi⁴⁷, L.S. Barnby¹¹⁶, E. Barreau¹⁰⁴, V. Barret¹²⁸, L. Barreto¹¹¹, C. Bartels¹²⁰, K. Barth³³, E. Bartsch⁶⁵, N. Bastid¹²⁸, S. Basu⁷⁶, G. Batigne¹⁰⁴, D. Battistini⁹⁶, B. Batyunya¹⁴³, D. Bauri⁴⁸, J.L. Bazo Alba¹⁰², I.G. Bearden⁸⁴, C. Beattie¹³⁹,
P. Becht 98, ID, D. Behera 49, ID, I. Belikov 130, ID, A.D.C. Bell Hechavarria 127, ID, F. Bellini 26, ID, R. Bellwied 117, ID, S. Belokurova 142, ID, L.G.E. Beltran 110, ID, Y.A.V. Beltran 45, ID, G. Bencedi 47, ID, A. Bensaoula 117, S. Beole 25, ID, Y. Berdnikov 142, ID, A. Berdnikova 95, ID, L. Bergmann 95, ID, M.G. Besoiu 64, ID, L. Betev 33, ID, P.P. Bhaduri 136, ID, A. Bhasin 92, ID, M.A. Bhat 4, ID, B. Bhattacharjee 42, ID, L. Bianchi 25, ID, N. Bianchi 50, ID, J. Bielčík 36, ID, J. Bielčíková 87, ID, A.P. Bigot 130, ID, A. Bilandzic 96, ID, G. Biro 47, ID, S. Biswas 4, ID, N. Bize 104, ID, J.T. Blair 109, ID, D. Blau 142, ID, M.B. Blidaru 98, ID, N. Bluhme 39, C. Blume 65, ID, G. Boca 22,56, ID, F. Bock 88, ID, T. Bodova 21, ID, S. Boi 23, ID, J. Bok 17, ID, L. Boldizsár 47, ID, M. Bombara 38, ID, P.M. Bond 33, ID, G. Bonomi 135,56, ID, H. Borel 131, ID, A. Borissov 142, ID, A.G. Borquez Carcamo 95, ID, H. Bossi 139, ID, E. Botta 25, ID, Y.E.M. Bouziani 65, ID, L. Bratrud 65, ID, P. Braun-Munzinger 98, ID, M. Bregant 111, ID, M. Broz 36, ID, G.E. Bruno 97,32, ID, M.D. Buckland 24, ID, D. Budnikov 142, ID, H. Buesching 65, ID, S. Bufalino 30, ID, P. Buhler 103, ID, N. Burmasov 142, ID, Z. Buthelezi 69,124, ID, A. Bylinkin 21, ID, S.A. Bysiak 108, J.C. Cabanillas Noris 110, ID, M.F.T. Cabrera 117, M. Cai 6, ID, H. Caines 139, ID, A. Caliva 29, ID, E. Calvo Villar 102, ID, J.M.M. Camacho 110, ID, P. Camerini 24, ID, F.D.M. Canedo 111, ID, S.L. Cantway 139, ID, M. Carabas 114, ID, A.A. Carballo 33, ID, F. Carnesecchi 33, ID, R. Caron 129, ID, L.A.D. Carvalho 111, ID, J. Castillo Castellanos 131, ID, F. Catalano 33,25, ID, S. Cattaruzzi 24, ID, C. Ceballos Sanchez 143, ID, R. Cerri 25, I. Chakaberia 75, ID, P. Chakraborty 137,48, ID, S. Chandra 136, ID, S. Chapeland 33, ID, M. Chartier 120, ID, S. Chattopadhyay 136, ID, S. Chattopadhyay 100, ID, T. Cheng 98,6, ID, C. Cheshkov 129, ID, V. Chibante Barroso 33, ID, D.D. Chinellato 112, ID, E.S. Chizzali 96, ID,II, J. Cho 59, ID, S. Cho 59, ID, P. Chochula 33, ID, D. Choudhury 42, P. Christakoglou 85, ID, C.H. Christensen 84, ID, P. Christiansen 76, ID, T. Chujo 126, ID, M. Ciacco 30, ID, C. Cicalo 53, ID, M.R. Ciupek 98, G. Clai 52,III, F. Colamaria 51, ID, J.S. Colburn 101, D. Colella 97,32, ID, M. Colocci 26, ID, M. Concas 33, ID, G. Conesa Balbastre 74, ID, Z. Conesa del Valle 132, ID, G. Contin 24, ID, J.G. Contreras 36, ID, M.L. Coquet 131, ID, P. Cortese 134,57, ID, M.R. Cosentino 113, ID, F. Costa 33, ID, S. Costanza 22,56, ID, C. Cot 132, ID, J. Crkovská 95, ID, P. Crochet 128, ID, R. Cruz-Torres 75, ID, P. Cui 6, ID, A. Dainese 55, ID, M.C. Danisch 95, ID, A. Danu 64, ID, P. Das 81, ID, P. Das 4, ID, S. Das 4, ID, A.R. Dash 127, ID, S. Dash 48, ID, A. De Caro 29, ID, G. de Cataldo 51, ID, J. de Cuveland 39, A. De Falco 23, ID, D. De Gruttola 29, ID, N. De Marco 57, ID, C. De Martin 24, ID, S. De Pasquale 29, ID, R. Deb 135, ID, R. Del Grande 96, ID, L. Dello Stritto 33,29, ID, W. Deng 6, ID, P. Dhankher 19, ID, D. Di Bari 32, ID, A. Di Mauro 33, ID, B. Diab 131, ID, R.A. Diaz 143,7, ID, T. Dietel 115, ID, Y. Ding 6, ID, J. Ditzel 65, ID, R. Divià 33, ID, D.U. Dixit 19, ID, Ø. Djuvsland 21, U. Dmitrieva 142, ID, A. Dobrin 64, ID, B. Dönigus 65, ID, J.M. Dubinski 137, ID, A. Dubla 98, ID, S. Dudi 91, ID, P. Dupieux 128, ID, M. Durkac 107, N. Dzalaiova 13, T.M. Eder 127, ID, R.J. Ehlers 75, ID, F. Eisenhut 65, ID, R. Ejima 93, D. Elia 51, ID, B. Erazmus 104, ID, F. Ercolessi 26, ID, B. Espagnon 132, ID, G. Eulisse 33, ID, D. Evans 101, ID, S. Evdokimov 142, ID, L. Fabbietti 96, ID, M. Faggin 28, ID, J. Faivre 74, ID, F. Fan 6, ID, W. Fan 75, ID, A. Fantoni 50, ID, M. Fasel 88, ID, A. Feliciello 57, ID, G. Feofilov 142, ID, A. Fernández Téllez 45, ID, L. Ferrandi 111, ID, M.B. Ferrer 33, ID, A. Ferrero 131, ID, C. Ferrero 57, ID,IV, A. Ferretti 25, ID, V.J.G. Feuillard 95, ID, V. Filova 36, ID, D. Finogeev 142, ID, F.M. Fionda 53, ID, E. Flatland 33, F. Flor 117, ID, A.N. Flores 109, ID, S. Foertsch 69, ID, I. Fokin 95, ID, S. Fokin 142, ID, E. Fragiacomo 58, ID, E. Frajna 47, ID, U. Fuchs 33, ID, N. Funicello 29, ID, C. Furget 74, ID, A. Furs 142, ID, T. Fusayasu 99, ID, J.J. Gaardhøje 84, ID, M. Gagliardi 25, ID, A.M. Gago 102, ID, T. Gahlaut 48, C.D. Galvan 110, ID, D.R. Gangadharan 117, ID, P. Ganoti 79, ID, C. Garabatos 98, ID, T. García Chávez 45, ID, E. Garcia-Solis 9, ID, C. Gargiulo 33, ID, P. Gasik 98, ID, A. Gautam 119, ID, M.B. Gay Ducati 67, ID, M. Germain 104, ID, A. Ghimouz 126, C. Ghosh 136, M. Giacalone 52, ID, G. Gioachin 30, ID, P. Giubellino 98,57, ID, P. Giubilato 28, ID, A.M.C. Glaenzer 131, ID, P. Glässel 95, ID, E. Glimos 123, ID, D.J.Q. Goh 77, V. Gonzalez 138, ID, P. Gordeev 142, ID, M. Gorgon 2, ID, K. Goswami 49, ID, S. Gotovac 34, V. Grabski 68, ID, L.K. Graczykowski 137, ID, E. Grecka 87, ID, A. Grelli 60, ID, C. Grigoras 33, ID, V. Grigoriev 142, ID, S. Grigoryan 143,1, ID, F. Grosa 33, ID, J.F. Grosse-Oetringhaus 33, ID, R. Grosso 98, ID, D. Grund 36, ID, N.A. Grunwald 95, G.G. Guardiano 112, ID, R. Guernane 74, ID, M. Guilbaud 104, ID,
K. Gulbrandsen 84, ID, T. Gündem 65, ID, T. Gunji 125, ID, W. Guo 6, ID, A. Gupta 92, ID, R. Gupta 92, ID, R. Gupta 49, ID,
K. Gwizdziel 137, ID, L. Gyulai 47, ID, C. Hadjidakis 132, ID, F.U. Haider 92, ID, S. Haidlova 36, ID, M. Haldar 4,
H. Hamagaki 77, ID, A. Hamdi 75, ID, Y. Han 140, ID, B.G. Hanley 138, ID, R. Hannigan 109, ID, J. Hansen 76, ID,
J.W. Harris 139, ID, A. Harton 9, ID, M.V. Hartung 65, ID, H. Hassan 118, ID, D. Hatzifotiadou 52, ID, P. Hauer 43, ID,
L.B. Havener 139, ID, E. Hellbär 98, ID, H. Helstrup 35, ID, M. Hemmer 65, ID, T. Herman 36, ID, S.G. Hernandez 117,
G. Herrera Corral 8, ID, F. Herrmann 127, S. Herrmann 129, ID, K.F. Hetland 35, ID, B. Heybeck 65, ID,
H. Hillemanns 33, ID, B. Hippolyte 130, ID, F.W. Hoffmann 71, ID, B. Hofman 60, ID, G.H. Hong 140, ID, M. Horst 96, ID,
A. Horzyk 2, ID, Y. Hou 6, ID, P. Hristov 33, ID, P. Huhn 65, L.M. Huhta 118, ID, T.J. Humanic 89, ID, A. Hutson 117, ID,
D. Hutter 39, ID, M.C. Hwang 19, ID, R. Ilkaev 142, H. Ilyas 14, ID, M. Inaba 126, ID, G.M. Innocenti 33, ID,
M. Ippolitov 142, ID, A. Isakov 85, ID, T. Isidori 119, ID, M.S. Islam 100, ID, M. Ivanov 98, ID, M. Ivanov 13, V. Ivanov 142, ID,
K.E. Iversen 76, ID, M. Jablonski 2, ID, B. Jacak 19,75, ID, N. Jacazio 26, ID, P.M. Jacobs 75, ID, S. Jadlovska 107,
J. Jadlovsky 107, S. Jaelani 83, ID, C. Jahnke 111, ID, M.J. Jakubowska 137, ID, M.A. Janik 137, ID, T. Janson 71,
S. Ji 17, ID, S. Jia 10, ID, A.A.P. Jimenez 66, ID, F. Jonas 75,88,127, ID, D.M. Jones 120, ID, J.M. Jowett 33,98, ID, J. Jung 65, ID,
M. Jung 65, ID, A. Junique 33, ID, A. Jusko 101, ID, J. Kaewjai 106, P. Kalinak 61, ID, A.S. Kalteyer 98, ID, A. Kalweit 33, ID,
A. Karasu Uysal 73, ID, V, D. Karatovic 90, ID, O. Karavichev 142, ID, T. Karavicheva 142, ID, P. Karczmarczyk 137, ID,
E. Karpechev 142, ID, M.J. Karwowska 33,137, ID, U. Kebschull 71, ID, R. Keidel 141, ID, D.L.D. Keijdener 60, M. Keil 33, ID,
B. Ketzer 43, ID, S.S. Khade 49, ID, A.M. Khan 121, ID, S. Khan 16, ID, A. Khanzadeev 142, ID, Y. Kharlov 142, ID,
A. Khatun 119, ID, A. Khuntia 36, ID, Z. Khuranova 65, ID, B. Kileng 35, ID, B. Kim 105, ID, C. Kim 17, ID, D.J. Kim 118, ID,
E.J. Kim 70, ID, J. Kim 140, ID, J. Kim 59, ID, J. Kim 70, ID, M. Kim 19, ID, S. Kim 18, ID, T. Kim 140, ID, K. Kimura 93, ID,
A. Kirkova 37, S. Kirsch 65, ID, I. Kisel 39, ID, S. Kiselev 142, ID, A. Kisiel 137, ID, J.P. Kitowski 2, ID, J.L. Klay 5, ID,
J. Klein 33, ID, S. Klein 75, ID, C. Klein-Bösing 127, ID, M. Kleiner 65, ID, T. Klemenz 96, ID, A. Kluge 33, ID,
C. Kobdaj 106, ID, T. Kollegger 98, A. Kondratyev 143, ID, N. Kondratyeva 142, ID, J. Konig 65, ID, S.A. Konigstorfer 96, ID,
P.J. Konopka 33, ID, G. Kornakov 137, ID, M. Korwieser 96, ID, S.D. Koryciak 2, ID, A. Kotliarov 87, ID, N. Kovacic 90,
V. Kovalenko 142, ID, M. Kowalski 108, ID, V. Kozhuharov 37, ID, I. Králik 61, ID, A. Kravčáková 38, ID, L. Krcal 33,39, ID,
M. Krivda 101,61, ID, F. Krizek 87, ID, K. Krizkova Gajdosova 33, ID, M. Kroesen 95, ID, M. Krüger 65, ID,
D.M. Krupova 36, ID, E. Kryshen 142, ID, V. Kučera 59, ID, C. Kuhn 130, ID, P.G. Kuijer 85, ID, T. Kumaoka 126,
D. Kumar 136, L. Kumar 91, ID, N. Kumar 91, S. Kumar 32, ID, S. Kundu 33, ID, P. Kurashvili 80, ID, A. Kurepin 142, ID,
A.B. Kurepin 142, ID, A. Kuryakin 142, ID, S. Kushpil 87, ID, V. Kuskov 142, ID, M. Kutyla 137, M.J. Kweon 59, ID,
Y. Kwon 140, ID, S.L. La Pointe 39, ID, P. La Rocca 27, ID, A. Lakrathok 106, M. Lamanna 33, ID, A.R. Landou 74, ID,
R. Langoy 122, ID, P. Larionov 33, ID, E. Laudi 33, ID, L. Lautner 33,96, ID, R. Lavicka 103, ID, R. Lea 135,56, ID, H. Lee 105, ID,
I. Legrand 46, ID, G. Legras 127, ID, J. Lehrbach 39, ID, T.M. Lelek 2, R.C. Lemmon 86, ID, I. León Monzón 110, ID,
M.M. Lesch 96, ID, E.D. Lesser 19, ID, P. Lévai 47, ID, X. Li 10, B.E. Liang-gilman 19, ID, J. Lien 122, ID, R. Lietava 101, ID,
I. Likmeta 117, ID, B. Lim 25, ID, S.H. Lim 17, ID, V. Lindenstruth 39, ID, A. Lindner 46, C. Lippmann 98, ID, D.H. Liu 6, ID,
J. Liu 120, ID, G.S.S. Liveraro 112, ID, I.M. Lofnes 21, ID, C. Loizides 88, ID, S. Lokos 108, ID, J. Lömker 60, ID,
P. Loncar 34, ID, X. Lopez 128, ID, E. López Torres 7, ID, P. Lu 98,121, ID, F.V. Lugo 68, ID, J.R. Luhder 127, ID,
M. Lunardon 28, ID, G. Luparello 58, ID, Y.G. Ma 40, ID, M. Mager 33, ID, A. Maire 130, ID, E.M. Majerz 2,
M.V. Makariev 37, ID, M. Malaev 142, ID, G. Malfattore 26, ID, N.M. Malik 92, ID, Q.W. Malik 20, S.K. Malik 92, ID,
L. Malinina 143, ID, I, VIII, D. Mallick 132, ID, N. Mallick 49, ID, G. Mandaglio 31,54, ID, S.K. Mandal 80, ID, V. Manko 142, ID,
F. Manso 128, ID, V. Manzari 51, ID, Y. Mao 6, ID, R.W. Marcjan 2, ID, G.V. Margagliotti 24, ID, A. Margotti 52, ID,
A. Marín 98, ID, C. Markert 109, ID, P. Martinengo 33, ID, M.I. Martínez 45, ID, G. Martínez García 104, ID,
M.P.P. Martins 111, ID, S. Masciocchi 98, ID, M. Masera 25, ID, A. Masoni 53, ID, L. Massacrier 132, ID, O. Massen 60, ID,
A. Mastroserio 133,51, ID, O. Matonoha 76, ID, S. Mattiazzo 28, ID, A. Matyja 108, ID, C. Mayer 108, ID,
A.L. Mazuecos 33, ID, F. Mazzaschi 25, ID, M. Mazzilli 33, ID, J.E. Mdhluli 124, ID, Y. Melikyan 44, ID,
A. Menchaca-Rocha 68, ID, J.E.M. Mendez 66, ID, E. Meninno 103, ID, A.S. Menon 117, ID, M. Meres 13, ID, Y. Miake 126,
L. Micheletti 33, ID, D.L. Mihaylov 96, ID, K. Mikhaylov 143,142, ID, D. Miśkowiec 98, ID, A. Modak 4, ID, B. Mohanty 81,
M. Mohisin Khan 16, ID, VI, M.A. Molander 44, ID, S. Monira 137, ID, C. Mordasini 118, ID, D.A. Moreira De Godoy 127, ID,
I. Morozov 142, ID, A. Morsch 33, ID, T. Mrnjavac 33, ID, V. Muccifora 50, ID, S. Muhuri 136, ID, J.D. Mulligan 75, ID,
A. Mulliri 23, ID, M.G. Munhoz 111, ID, R.H. Munzer 65, ID, H. Murakami 125, ID, S. Murray 115, ID, L. Musa 33, ID,
J. Musinsky 61, ID, J.W. Myrcha 137, ID, B. Naik 124, ID, A.I. Nambrath 19, ID, B.K. Nandi 48, ID, R. Nania 52, ID,
E. Nappi 51, ID, A.F. Nassirpour 18, ID, A. Nath 95, ID, C. Nattrass 123, ID, M.N. Naydenov 37, ID, A. Neagu 20,
A. Negru 114, E. Nekrasova 142, L. Nellen 66, ID, R. Nepeivoda 76, ID, S. Nese 20, ID, G. Neskovic 39, ID,
N. Nicassio 51, ID, B.S. Nielsen 84, ID, E.G. Nielsen 84, ID, S. Nikolaev 142, ID, S. Nikulin 142, ID, V. Nikulin 142, ID,
F. Noferini 52, ID, S. Noh 12, ID, P. Nomokonov 143, ID, J. Norman 120, ID, N. Novitzky 88, ID, P. Nowakowski 137, ID,
A. Nyanin 142, ID, J. Nystrand 21, ID, S. Oh 18, ID, A. Ohlson 76, ID, V.A. Okorokov 142, ID, J. Oleniacz 137, ID,
A. Onnerstad 118, ID, C. Oppedisano 57, ID, A. Ortiz Velasquez 66, ID, J. Otwinowski 108, ID, M. Oya 93, K. Oyama 77, ID,
Y. Pachmayer 95, ID, S. Padhan 48, ID, D. Pagano 135,56, ID, G. Paić 66, ID, S. Paisano-Guzmán 45, ID, A. Palasciano 51, ID,
S. Panebianco 131, ID, H. Park 126, ID, H. Park 105, ID, J. Park 59, ID, J.E. Parkkila 33, ID, Y. Patley 48, ID, B. Paul 23, ID,
M.M.D.M. Paulino 111, ID, H. Pei 6, ID, T. Peitzmann 60, ID, X. Peng 11, ID, M. Pennisi 25, ID, S. Perciballi 25, ID,
D. Peresunko 142, ID, G.M. Perez 7, ID, Y. Pestov 142, V. Petrov 142, ID, M. Petrovici 46, ID, R.P. Pezzi 104,67, ID,
S. Piano 58, ID, M. Pikna 13, ID, P. Pillot 104, ID, O. Pinazza 52,33, ID, L. Pinsky 117, C. Pinto 96, ID, S. Pisano 50, ID,
M. Płoskoń 75, ID, M. Planinic 90, F. Pliquett 65, M.G. Poghosyan 88, ID, B. Polichtchouk 142, ID, S. Politano 30, ID,
N. Poljak 90, ID, A. Pop 46, ID, S. Porteboeuf-Houssais 128, ID, V. Pozdniakov 143, ID, I.Y. Pozos 45, ID,
K.K. Pradhan 49, ID, S.K. Prasad 4, ID, S. Prasad 49, ID, R. Preghenella 52, ID, F. Prino 57, ID, C.A. Pruneau 138, ID,
I. Pshenichnov 142, ID, M. Puccio 33, ID, S. Pucillo 25, ID, Z. Pugelova 107, S. Qiu 85, ID, L. Quaglia 25, ID, S. Ragoni 15, ID,
A. Rai 139, ID, A. Rakotozafindrabe 131, ID, L. Ramello 134,57, ID, F. Rami 130, ID, M. Rasa 27, ID, S.S. Räsänen 44, ID,
R. Rath 52, ID, M.P. Rauch 21, ID, I. Ravasenga 33, ID, K.F. Read 88,123, ID, C. Reckziegel 113, ID, A.R. Redelbach 39, ID,
K. Redlich 80, ID, VII, C.A. Reetz 98, ID, H.D. Regules-Medel 45, A. Rehman 21, F. Reidt 33, ID, H.A. Reme-Ness 35, ID,
Z. Rescakova 38, K. Reygers 95, ID, A. Riabov 142, ID, V. Riabov 142, ID, R. Ricci 29, ID, M. Richter 20, ID,
A.A. Riedel 96, ID, W. Riegler 33, ID, A.G. Riffero 25, ID, C. Ristea 64, ID, M.V. Rodriguez 33, ID, M. Rodríguez
Cahuantzi 45, ID, S.A. Rodríguez Ramírez 45, ID, K. Røed 20, ID, R. Rogalev 142, ID, E. Rogochaya 143, ID,
T.S. Rogoschinski 65, ID, D. Rohr 33, ID, D. Röhrich 21, ID, P.F. Rojas 45, S. Rojas Torres 36, ID, P.S. Rokita 137, ID,
G. Romanenko 26, ID, F. Ronchetti 50, ID, A. Rosano 31,54, ID, E.D. Rosas 66, K. Roslon 137, ID, A. Rossi 55, ID,
A. Roy 49, ID, S. Roy 48, ID, N. Rubini 26, ID, D. Ruggiano 137, ID, R. Rui 24, ID, P.G. Russek 2, ID, R. Russo 85, ID,
A. Rustamov 82, ID, E. Ryabinkin 142, ID, Y. Ryabov 142, ID, A. Rybicki 108, ID, H. Rytkonen 118, ID, J. Ryu 17, ID,
W. Rzesa 137, ID, O.A.M. Saarimaki 44, ID, S. Sadhu 32, ID, S. Sadovsky 142, ID, J. Saetre 21, ID, K. Šafařík 36, ID,
S.K. Saha 4, ID, S. Saha 81, ID, B. Sahoo 49, ID, R. Sahoo 49, ID, S. Sahoo 62, D. Sahu 49, ID, P.K. Sahu 62, ID, J. Saini 136, ID,
K. Sajdakova 38, S. Sakai 126, ID, M.P. Salvan 98, ID, S. Sambyal 92, ID, D. Samitz 103, ID, I. Sanna 33,96, ID,
T.B. Saramela 111, D. Sarkar 84, ID, P. Sarma 42, ID, V. Sarritzu 23, ID, V.M. Sarti 96, ID, M.H.P. Sas 33, ID, S. Sawan 81, ID,
E. Scapparone 52, ID, J. Schambach 88, ID, H.S. Scheid 65, ID, C. Schiaua 46, ID, R. Schicker 95, ID, F. Schlepper 95, ID,
A. Schmah 98, C. Schmidt 98, ID, H.R. Schmidt 94, M.O. Schmidt 33, ID, M. Schmidt 94, N.V. Schmidt 88, ID,
A.R. Schmier 123, ID, R. Schotter 130, ID, A. Schröter 39, ID, J. Schukraft 33, ID, K. Schweda 98, ID, G. Scioli 26, ID,
E. Scomparin 57, ID, J.E. Seger 15, ID, Y. Sekiguchi 125, D. Sekihata 125, ID, M. Selina 85, ID, I. Selyuzhenkov 98, ID,
S. Senyukov 130, ID, J.J. Seo 95, ID, D. Serebryakov 142, ID, L. Serkin 66, ID, L. Šerkšnytė 96, ID, A. Sevcenco 64, ID,
T.J. Shaba 69, ID, A. Shabetai 104, ID, R. Shahoyan 33, A. Shangaraev 142, ID, B. Sharma 92, ID, D. Sharma 48, ID,
H. Sharma 55, ID, M. Sharma 92, ID, S. Sharma 77, ID, S. Sharma 92, ID, U. Sharma 92, ID, A. Shatat 132, ID, O. Sheibani 117, K. Shigaki 93, ID, M. Shimomura 78, J. Shin 12, S. Shirinkin 142, ID, Q. Shou 40, ID, Y. Sibiriak 142, ID, S. Siddhanta 53, ID, T. Siemiarczuk 80, ID, T.F. Silva 111, ID, D. Silvermyr 76, ID, T. Simantathammakul 106, R. Simeonov 37, ID, B. Singh 92, B. Singh 96, ID, K. Singh 49, ID, R. Singh 81, ID, R. Singh 92, ID, R. Singh 98,49, ID, S. Singh 16, ID, V.K. Singh 136, ID, V. Singhal 136, ID, T. Sinha 100, ID, B. Sitar 13, ID, M. Sitta 134,57, ID, T.B. Skaali 20, G. Skorodumovs 95, ID, M. Slupecki 44, ID, N. Smirnov 139, ID, R.J.M. Snellings 60, ID, E.H. Solheim 20, ID, J. Song 17, ID, C. Sonnabend 33,98, ID, J.M. Sonneveld 85, ID, F. Soramel 28, ID, A.B. Soto-hernandez 89, ID, R. Spijkers 85, ID, I. Sputowska 108, ID, J. Staa 76, ID, J. Stachel 95, ID, I. Stan 64, ID, P.J. Steffanic 123, ID, S.F. Stiefelmaier 95, ID, D. Stocco 104, ID, I. Storehaug 20, ID, P. Stratmann 127, ID, S. Strazzi 26, ID, A. Sturniolo 31,54, ID, C.P. Stylianidis 85, A.A.P. Suaide 111, ID, C. Suire 132, ID, M. Sukhanov 142, ID, M. Suljic 33, ID, R. Sultanov 142, ID, V. Sumberia 92, ID, S. Sumowidagdo 83, ID, I. Szarka 13, ID, M. Szymkowski 137, ID, S.F. Taghavi 96, ID, G. Taillepied 98, ID, J. Takahashi 112, ID, G.J. Tambave 81, ID, S. Tang 6, ID, Z. Tang 121, ID, J.D. Tapia Takaki 119, ID, N. Tapus 114, L.A. Tarasovicova 127, ID, M.G. Tarzila 46, ID, G.F. Tassielli 32, ID, A. Tauro 33, ID, A. Tavira García 132, ID, G. Tejeda Muñoz 45, ID, A. Telesca 33, ID, L. Terlizzi 25, ID, C. Terrevoli 117, ID, S. Thakur 4, ID, D. Thomas 109, ID, A. Tikhonov 142, ID, N. Tiltmann 33,127, ID, A.R. Timmins 117, ID, M. Tkacik 107, T. Tkacik 107, ID, A. Toia 65, ID, R. Tokumoto 93, K. Tomohiro 93, N. Topilskaya 142, ID, M. Toppi 50, ID, T. Tork 132, ID, V.V. Torres 104, ID, A.G. Torres Ramos 32, ID, A. Trifiró 31,54, ID, A.S. Triolo 33,31,54, ID, S. Tripathy 52, ID, T. Tripathy 48, ID, S. Trogolo 33, ID, V. Trubnikov 3, ID, W.H. Trzaska 118, ID, T.P. Trzcinski 137, ID, A. Tumkin 142, ID, R. Turrisi 55, ID, T.S. Tveter 20, ID, K. Ullaland 21, ID, B. Ulukutlu 96, ID, A. Uras 129, ID, M. Urioni 135, ID, G.L. Usai 23, ID, M. Vala 38, N. Valle 22, ID, L.V.R. van Doremalen 60, M. van Leeuwen 85, ID, C.A. van Veen 95, ID, R.J.G. van Weelden 85, ID, P. Vande Vyvre 33, ID, D. Varga 47, ID, Z. Varga 47, ID, P. Vargas Torres 66, M. Vasileiou 79, ID, A. Vasiliev 142, ID, O. Vázquez Doce 50, ID, O. Vazquez Rueda 117, ID, V. Vechernin 142, ID, E. Vercellin 25, ID, S. Vergara Limón 45, R. Verma 48, L. Vermunt 98, ID, R. Vértesi 47, ID, M. Verweij 60, ID, L. Vickovic 34, Z. Vilakazi 124, O. Villalobos Baillie 101, ID, A. Villani 24, ID, A. Vinogradov 142, ID, T. Virgili 29, ID, M.M.O. Virta 118, ID, V. Vislavicius 76, A. Vodopyanov 143, ID, B. Volkel 33, ID, M.A. Völkl 95, ID, S.A. Voloshin 138, ID, G. Volpe 32, ID, B. von Haller 33, ID, I. Vorobyev 33, ID, N. Vozniuk 142, ID, J. Vrláková 38, ID, J. Wan 40, C. Wang 40, ID, D. Wang 40, Y. Wang 40, ID, Y. Wang 6, ID, A. Wegrzynek 33, ID, F.T. Weiglhofer 39, S.C. Wenzel 33, ID, J.P. Wessels 127, ID, J. Wiechula 65, ID, J. Wikne 20, ID, G. Wilk 80, ID, J. Wilkinson 98, ID, G.A. Willems 127, ID, B. Windelband 95, ID, M. Winn 131, ID, J.R. Wright 109, ID, W. Wu 40, Y. Wu 121, ID, Z. Xiong 121, R. Xu 6, ID, A. Yadav 43, ID, A.K. Yadav 136, ID, S. Yalcin 73, ID, Y. Yamaguchi 93, ID, S. Yang 21, S. Yano 93, ID, E.R. Yeats 19, Z. Yin 6, ID, I.-K. Yoo 17, ID, J.H. Yoon 59, ID, H. Yu 12, S. Yuan 21, A. Yuncu 95, ID, V. Zaccolo 24, ID, C. Zampolli 33, ID, F. Zanone 95, ID, N. Zardoshti 33, ID, A. Zarochentsev 142, ID, P. Závada 63, ID, N. Zaviyalov 142, M. Zhalov 142, ID, B. Zhang 6, ID, C. Zhang 131, ID, L. Zhang 40, ID, M. Zhang 6, ID, S. Zhang 40, ID, X. Zhang 6, ID, Y. Zhang 121, Z. Zhang 6, ID, M. Zhao 10, ID, V. Zherebchevskii 142, ID, Y. Zhi 10, C. Zhong 40, D. Zhou 6, ID, Y. Zhou 84, ID, J. Zhu 55,6, ID, Y. Zhu 6, S.C. Zugravel 57, ID, N. Zurlo 135,56, ID

<footnote n="1">¹ A.I. Alikhanyan National Science Laboratory (Yerevan Physics Institute) Foundation, Yerevan, Armenia</footnote>

<footnote n="2">² AGH University of Krakow, Cracow, Poland</footnote>

<footnote n="3">³ Bogolyubov Institute for Theoretical Physics, National Academy of Sciences of Ukraine, Kiev, Ukraine</footnote>

<footnote n="4">⁴ Bose Institute, Department of Physics and Centre for Astroparticle Physics and Space Science (CAPSS), Kolkata, India</footnote>

<footnote n="5">⁵ California Polytechnic State University, San Luis Obispo, CA, United States</footnote>

<footnote n="6">⁶ Central China Normal University, Wuhan, China</footnote>

<footnote n="7">⁷ Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear (CEADEN), Havana, Cuba</footnote>

<footnote n="8">⁸ Centro de Investigación y de Estudios Avanzados (CINVESTAV), Mexico City and Mérida, Mexico</footnote>

<footnote n="9">⁹ Chicago State University, Chicago, IL, United States</footnote>

<footnote n="10">¹⁰ China Institute of Atomic Energy, Beijing, China</footnote>

<footnote n="11">¹¹ China University of Geosciences, Wuhan, China</footnote>

<footnote n="12">¹² Chungbuk National University, Cheongju, Republic of Korea</footnote>

<footnote n="13">¹³ Comenius University Bratislava, Faculty of Mathematics, Physics and Informatics, Bratislava, Slovak Republic</footnote>

<footnote n="14">¹⁴ COMSATS University Islamabad, Islamabad, Pakistan</footnote>

<footnote n="15">¹⁵ Creighton University, Omaha, NE, United States</footnote>
16 Department of Physics, Aligarh Muslim University, Aligarh, India

17 Department of Physics, Pusan National University, Pusan, Republic of Korea

18 Department of Physics, Sejong University, Seoul, Republic of Korea

19 Department of Physics, University of California, Berkeley, CA, United States

20 Department of Physics, University of Oslo, Oslo, Norway

21 Department of Physics and Technology, University of Bergen, Bergen, Norway

22 Dipartimento di Fisica, Università di Pavia, Pavia, Italy

23 Dipartimento di Fisica dell'Università and Sezione INFN, Cagliari, Italy

24 Dipartimento di Fisica dell'Università and Sezione INFN, Trieste, Italy

25 Dipartimento di Fisica dell'Università and Sezione INFN, Turin, Italy

26 Dipartimento di Fisica e Astronomia dell'Università and Sezione INFN, Bologna, Italy

27 Dipartimento di Fisica e Astronomia dell'Università and Sezione INFN, Catania, Italy

28 Dipartimento di Fisica e Astronomia dell'Università and Sezione INFN, Padova, Italy

29 Dipartimento di Fisica 'E.R. Caianiello' dell'Università and Gruppo Collegato INFN, Salerno, Italy

30 Dipartimento DISAT del Politecnico and Sezione INFN, Turin, Italy

31 Dipartimento di Scienze MIFT, Università di Messina, Messina, Italy

32 Dipartimento Interateneo di Fisica 'M. Merlin' and Sezione INFN, Bari, Italy

33 European Organization for Nuclear Research (CERN), Geneva, Switzerland

34 Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture, University of Split, Split, Croatia

35 Faculty of Engineering and Science, Western Norway University of Applied Sciences, Bergen, Norway

36 Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Prague, Czech Republic

37 Faculty of Physics, Sofia University, Sofia, Bulgaria

38 Faculty of Science, P.J. Šafárik University, Košice, Slovak Republic

39 Frankfurt Institute for Advanced Studies, Johann Wolfgang Goethe-Universität Frankfurt, Frankfurt, Germany

40 Fudan University, Shanghai, China

41 Gangneung-Wonju National University, Gangneung, Republic of Korea

42 Gauhati University, Department of Physics, Guwahati, India

43 Helmholtz-Institut für Strahlen- und Kernphysik, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany

44 Helsinki Institute of Physics (HIP), Helsinki, Finland

45 High Energy Physics Group, Universidad Autónoma de Puebla, Puebla, Mexico

46 Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest, Romania

47 HUN-REN Wigner Research Centre for Physics, Budapest, Hungary

48 Indian Institute of Technology Bombay (IIT), Mumbai, India

49 Indian Institute of Technology Indore, Indore, India

50 INFN, Laboratori Nazionali di Frascati, Frascati, Italy

51 INFN, Sezione di Bari, Bari, Italy

52 INFN, Sezione di Bologna, Bologna, Italy

53 INFN, Sezione di Cagliari, Cagliari, Italy

54 INFN, Sezione di Catania, Catania, Italy

55 INFN, Sezione di Padova, Padova, Italy

56 INFN, Sezione di Pavia, Pavia, Italy

57 INFN, Sezione di Torino, Turin, Italy

58 INFN, Sezione di Trieste, Trieste, Italy

59 Inha University, Incheon, Republic of Korea

60 Institute for Gravitational and Subatomic Physics (GRASP), Utrecht University/Nikhef, Utrecht, Netherlands

61 Institute of Experimental Physics, Slovak Academy of Sciences, Košice, Slovak Republic

62 Institute of Physics, Homi Bhabha National Institute, Bhubaneswar, India

63 Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic

64 Institute of Space Science (ISS), Bucharest, Romania

65 Institut für Kernphysik, Johann Wolfgang Goethe-Universität Frankfurt, Frankfurt, Germany

66 Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Mexico City, Mexico

67 Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil

68 Instituto de Física, Universidad Nacional Autónoma de México, Mexico City, Mexico

69 iThemba LABS, National Research Foundation, Somerset West, South Africa

70 Jeonbuk National University, Jeonju, Republic of Korea

71 Johann-Wolfgang-Goethe-Universität Frankfurt Institut für Informatik, Fachbereich Informatik und Mathematik, Frankfurt, Germany

72 Korea Institute of Science and Technology Information, Daejeon, Republic of Korea

73 KTO Karatay University, Konya, Turkey

74 Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble-Alpes, CNRS-IN2P3, Grenoble, France

75 Lawrence Berkeley National Laboratory, Berkeley, CA, United States

76 Lund University Department of Physics, Division of Particle Physics, Lund, Sweden

77 Nagasaki Institute of Applied Science, Nagasaki, Japan

78 Nara Women's University (NWU), Nara, Japan

79 National and Kapodistrian University of Athens, School of Science, Department of Physics, Athens, Greece

80 National Centre for Nuclear Research, Warsaw, Poland

81 National Institute of Science Education and Research, Homi Bhabha National Institute, Jatni, India

82 National Nuclear Research Center, Baku, Azerbaijan

83 National Research and Innovation Agency - BRIN, Jakarta, Indonesia

84 Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark

85 Nikhef, National institute for subatomic physics, Amsterdam, Netherlands

86 Nuclear Physics Group, STFC Daresbury Laboratory, Daresbury, United Kingdom

87 Nuclear Physics Institute of the Czech Academy of Sciences, Husinec-Řež, Czech Republic

88 Oak Ridge National Laboratory, Oak Ridge, TN, United States

89 Ohio State University, Columbus, OH, United States

90 Physics department, Faculty of science, University of Zagreb, Zagreb, Croatia

91 Physics Department, Panjab University, Chandigarh, India

92 Physics Department, University of Jammu, Jammu, India

93 Physics Program and International Institute for Sustainability with Knotted Chiral Meta Matter (SKCM2), Hiroshima University, Hiroshima, Japan

94 Physikalisches Institut, Eberhard-Karls-Universität Tübingen, Tübingen, Germany

95 Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
⁹⁶ Physik Department, Technische Universität München, Munich, Germany

⁹⁷ Politecnico di Bari and Sezione INFN, Bari, Italy

⁹⁸ Research Division and ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany

⁹⁹ Saga University, Saga, Japan

¹⁰⁰ Saha Institute of Nuclear Physics, Homi Bhabha National Institute, Kolkata, India

¹⁰¹ School of Physics and Astronomy, University of Birmingham, Birmingham, United Kingdom

¹⁰² Sección Física, Departamento de Ciencias, Pontificia Universidad Católica del Perú, Lima, Peru

¹⁰³ Stefan Meyer Institut für Subatomare Physik (SMI), Vienna, Austria

¹⁰⁴ SUBATECH, IMT Atlantique, Nantes Université, CNRS-IN2P3, Nantes, France

¹⁰⁵ Sungkyunkwan University, Suwon City, Republic of Korea

¹⁰⁶ Suranaree University of Technology, Nakhon Ratchasima, Thailand

¹⁰⁷ Technical University of Košice, Košice, Slovak Republic

¹⁰⁸ The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Cracow, Poland

¹⁰⁹ The University of Texas at Austin, Austin, TX, United States

¹¹⁰ Universidad Autónoma de Sinaloa, Culiacán, Mexico

¹¹¹ Universidade de São Paulo (USP), São Paulo, Brazil

¹¹² Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil

¹¹³ Universidade Federal do ABC, Santo Andre, Brazil

¹¹⁴ Universitatea Nationala de Stiinta si Tehnologie Politehnica Bucuresti, Bucharest, Romania

¹¹⁵ University of Cape Town, Cape Town, South Africa

¹¹⁶ University of Derby, Derby, United Kingdom

¹¹⁷ University of Houston, Houston, TX, United States

¹¹⁸ University of Jyväskylä, Jyväskylä, Finland

¹¹⁹ University of Kansas, Lawrence, KS, United States

¹²⁰ University of Liverpool, Liverpool, United Kingdom

¹²¹ University of Science and Technology of China, Hefei, China

¹²² University of South-Eastern Norway, Kongsberg, Norway

¹²³ University of Tennessee, Knoxville, TN, United States

¹²⁴ University of the Witwatersrand, Johannesburg, South Africa

¹²⁵ University of Tokyo, Tokyo, Japan

¹²⁶ University of Tsukuba, Tsukuba, Japan

¹²⁷ Universität Münster, Institut für Kernphysik, Münster, Germany

¹²⁸ Université Clermont Auvergne, CNRS/IN2P3, LPC, Clermont-Ferrand, France

¹²⁹ Université de Lyon, CNRS/IN2P3, Institut de Physique des 2 Infinis de Lyon, Lyon, France

¹³⁰ Université de Strasbourg, CNRS, IPHC UMR 7178, F-67000 Strasbourg, France

¹³¹ Université Paris-Saclay, Centre d'Etudes de Saclay (CEA), IRFU, Département de Physique Nucléaire (DPhN), Saclay, France

¹³² Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France

¹³³ Università degli Studi di Foggia, Foggia, Italy

¹³⁴ Università di Piemonte Orientale, Vercelli, Italy

¹³⁵ Università di Brescia, Brescia, Italy

¹³⁶ Variable Energy Cyclotron Centre, Homi Bhabha National Institute, Kolkata, India

¹³⁷ Warsaw University of Technology, Warsaw, Poland

¹³⁸ Wayne State University, Detroit, MI, United States

¹³⁹ Yale University, New Haven, CT, United States

¹⁴⁰ Yonsei University, Seoul, Republic of Korea

¹⁴¹ Zentrum für Technologie und Transfer (ZTT), Worms, Germany

¹⁴² Affiliated with an institute covered by a cooperation agreement with CERN

¹⁴³ Affiliated with an international laboratory covered by a cooperation agreement with CERN

¹ Deceased.

II Also at: Max-Planck-Institut für Physik, Munich, Germany.

III Also at: Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Bologna, Italy.

IV Also at: Dipartimento DET del Politecnico di Torino, Turin, Italy.

V Also at: Yildiz Technical University, Istanbul, Türkiye.

VI Also at: Department of Applied Physics, Aligarh Muslim University, Aligarh, India.

VII Also at: Institute of Theoretical Physics, University of Wroclaw, Poland.

VIII Also at: An institution covered by a cooperation agreement with CERN.