Testing CPT symmetry via precise mass measurements of multi-strange baryons in ALICE
Romain Schotter
备注：
6 pages, 1 figure, Proceedings for the 42nd International Conference on High Energy Physics (ICHEP 2024), 18-24 July 2024; submitted to Proceedings of Science (PoS)
本文报告了ALICE合作组在LHC Run 2期间收集的质子-质子碰撞数据（质心能量 $\sqrt{s} = 13$ TeV）中，对 $Ξ^{-}$、$\overlineΞ^{+}$、$Ω^{-}$、$\overlineΩ^{+}$ 的质量以及粒子与反粒子之间质量差的测量结果。所依赖的数据样本远大于以往实验使用的样本，这些结果显著改善了先前测量得到的数值，从而为在多奇异重子领域以前所未有的精度直接检验CPT对称性提供了机会。
英文摘要：
These proceedings present measurements of the $Ξ^{-}$, $\overlineΞ^{+}$, $Ω^{-}$, $\overlineΩ^{+}$ masses and mass differences between particle and anti-particle, in pp collisions at $\sqrt{s} = 13$ TeV collected by the ALICE Collaboration during the LHC Run 2. Relying on a data sample much larger than those used in past experiments, the results improve significantly the values obtained from previous measurements and thus offer the opportunity to test directly the CPT symmetry to an unprecedented level of precision in the multi-strange baryon sector.
The status of the charged multi-strange baryon analysis (Xi-, anti-Xi+, Omega-, anti-Omega+) at LHC energies is presented. This report is based on the results obtained with ALICE (A Large Ion Collider Experiment), profiting from the characteristic cascade-decay topology. A special attention is drawn to the early pp data-taking period (2009-2010) and subsequently, on the uncorrected pT-spectra extracted at mid-rapidity for centre of mass energies of 0.9 TeV and 7 TeV.
These proceedings summarise recent measurements of angular correlations between the $Ξ$ baryon and identified hadrons in pp collisions at $\sqrt{s}=13\,\mathrm{TeV}$ using the ALICE detector. The results are compared with both string-based (PYTHIA8 with extensions) and core-corona (EPOS-LHC) models, to improve our understanding of strangeness and baryon production in small systems. The results favour baryon production through string junctions over diquark breaking, but the PYTHIA models fail at describing the relatively wide $Ξ-$strangeness jet peak, indicating stronger diffusion of strange qu…
The production of charged multi-strange particles is studied with the ALICE experiment at the CERN LHC. Measurements of the central rapidity yields of $Ξ^-$ and $Ω^-$ baryons, as well as their antiparticles, are presented as a function of transverse momentum ($p_\mathrm{t}$) for inelastic pp collisions at $\sqrt{s}=7$ TeV and compared to existing measurements performed at the same and/or at lower energies. The results are also compared to predictions from two different tunes of the PYTHIA event generator. We find that data significantly exceed the production rates from those models. Finally, w…
We present the new studies which are performed with the aim of better understanding the production mechanisms for strange particles, and hence the strangeness enhancement phenomenon, in small-collision systems. In one of the recent studies, the very forward energy transported by beam remnants (spectators) and detected by the Zero Degree Calorimeters (ZDC) is used to classify events. The contribution of the effective energy and the particle multiplicity on strangeness production is studied using a multi-differential approach in order to disentangle initial and final state effects. In the second…
The production of strange and multi-strange hadrons in proton-proton (pp) and lead-lead (Pb-Pb) collisions is studied with the ALICE experiment at the CERN LHC. These particles are reconstructed via their weak decay topologies, exploiting the tracking and particle identification capabilities of ALICE. Measurements of central rapidity yields of $Λ$, $Ξ^{-}$ and $Ω^{-}$ baryons, their antiparticles and ${\mathrm K}^{0}_{S}$ mesons are presented as a function of transverse momentum for Pb-Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV. They are compared to those observed in pp collisions as well as to…
In the perspective of comparisons between proton-proton and heavy-ion physics, understanding the production mechanisms (soft and hard) in pp that lead to strange particles is of importance. Measurements of charged multi-strange (anti-)baryons (Omega and Xi) are presented for pp collisions at sqrt(s) = 7 TeV. This report is based on results obtained by ALICE (A Large Ion Collider Experiment) from the 2010 data-taking. Taking advantage of the characteristic cascade-decay topology, the identification of Xi-, anti-Xi+, Omega- and anti-Omega+ can be performed, over a wide range of momenta (e.g. fro…
Strange quark and particle production is studied at the LHC with unprecedented high beam energies in both heavy-ion and proton-proton collisions: on the one hand, strangeness is used for investigating chemical equilibration and bulk properties; on the other hand, strange particles contribute to probe different kinematical domains, from the one where collective phenomena are at play up to the region dominated by pQCD-calculable processes. We highlight the suitability of the ALICE experiment for this topic, presenting our latest measurements and comparing them to models.
Hadrons measured in proton-proton collisions at sqrt(s) = 0.9 and 7 TeV with the ALICE detector have been identified using various techniques: the specific energy loss and the time-of flight information for charged pions, kaons and protons, the displaced vertex resulting from their weak decay for K0, Lambda and Xi and the kink topology of decaying charged kaons. These various particle identification tools give the best separation at different momentum ranges and the results are combined to obtain spectra from pt = 100 MeV/c to 2.5 GeV/c. This allows to extract total yields. In detail we discus…
We present measurements of hadronic resonance, strange and multi-strange particle production in collisions of Xe-Xe and Pb-Pb at the center-of-mass energies of $\sqrt{s_{NN}}=5.44$ and $5.02$ TeV, respectively, by the ALICE collaboration at the LHC. Particle ratios are presented as a function of multiplicity for $K^{0}_{s}$, $Λ$, $Ξ^{-}$, $\barΞ^{+}$, $Ω^{-}$, $\barΩ^{+}$, $ρ(770)^{0}$, $K^{\ast}(892)^{0}$, $ϕ(1020)$ and $Λ(1520)$. Our results are discussed and compared with predictions of QCD-inspired event generators. Additionally, comparisons with lower energy measurements and smaller syste…
In these proceedings, two multi-differential analyses performed in pp collisions collected by the ALICE collaboration during the LHC Run 2 are presented. One investigates the dependence of strange particle production with multiplicity and effective energy, whereas the other clarifies how strangeness enhancement is correlated to the leading jet in the event. The results suggest that strangeness production at the LHC depends strongly on effective energy, and originates dominantly from the transverse region with respect to the leading jet direction.
We present the measurements of strange and multi-strange hadrons in high energy pp and Pb-Pb collisions at the Large Hadron Collider (LHC) at CERN. The data for these measurements were collected by the ALICE detector in 2010 and 2011. By comparing strangeness data where Quark-Gluon Plasma (QGP) is not expected to be produced (pp collisions) with data where the energy-density of the collision is sufficient to produce the QGP (central and mid-central Pb-Pb collisions), we are able to investigate the properties of the QGP. We characterize the matter created in the collision by presenting strange …
The production of mesons containing strange quarks (K$^0_s$, $ϕ$) and both singly and doubly strange baryons ($Λ$, Anti-$Λ$, and $Ξ$+Anti-$Ξ$) are measured at central rapidity in pp collisions at $\sqrt{s}$ = 0.9 TeV with the ALICE experiment at the LHC. The results are obtained from the analysis of about 250 k minimum bias events recorded in 2009. Measurements of yields (dN/dy) and transverse momentum spectra at central rapidities for inelastic pp collisions are presented. For mesons, we report yields (<dN/dy>) of 0.184 $\pm$ 0.002 stat. $\pm$ 0.006 syst. for K$^0_s$ and 0.021 $\pm$ 0.004 sta…
The study of energy and multiplicity dependence of strange hadron production in proton-proton collisions provides a powerful tool to understand similarities and differences between small and large collision systems. In order to better understand the origin of strangeness enhancement in pp new multi-differential analyses have been performed. The first separates the contribution of soft and hard processes, such as jets, to strange hadron production through two-particle correlation techniques. The second exploits the concept of the effective energy available for particle production in the event, …
The main goal of the ALICE experiment is to study the properties of the hot and dense medium created in ultra-relativistic heavy-ion collisions. The measurement of the (multi-)strange particles is an important tool to understand particle production mechanisms and the dynamics of the quark-gluon plasma (QGP). We report on the production of K$^{0}_{S}$, $Λ$($\overlineΛ$), $Ξ^{-}$($\overlineΞ^{+}$) and $Ω^{-}$($\overlineΩ^{+}$) in proton-lead (p-Pb) collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV and lead-lead (Pb-Pb) collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV measured by ALICE at the LHC. The com…
The ALICE experiment has studied strangeness production in different collision systems (pp, p-Pb, Xe-Xe and Pb-Pb) and energies. The ratio of the strange particle yield to pion yield as a function of multiplicity for different collision energies and systems follow a continuously increasing trend ("enhancement") from low multiplicity pp to high-multiplicity Pb-Pb collisions, independent of the initial collision energy and colliding particles. It is also observed that the enhancement is larger for the particles with larger strangeness content. Several other features that were observed in large c…
Transverse momentum spectra and yields of charged $Ξ$ and $Ω$ at mid-rapidity in pp, p-Pb and Pb-Pb collisions at the LHC have been measured by the ALICE Collaboration. These baryons are identified by reconstruction of their weak decay topology, in modes with only charged decay products, using the excellent tracking and particle identification capabilities of the detector. The recent measurements of the multi-strange baryon production relative to non-strange particles in p-Pb collisions are presented: this would help to understand the change in relative strangeness production from pp collision…
One of the key results of the LHC Run 1 was the observation of an enhanced production of strange particles in high multiplicity pp and p--Pb collisions at $\sqrt{s_\mathrm{NN}}$ = 7 and 5.02 TeV, respectively. The strangeness enhancement is investigated by measuring the evolution with multiplicity of single-strange and multi-strange baryon production relative to non-strange particles. A smooth increase of strange particle yields relative to the non-strange ones with event multiplicity has been observed in such systems. We report the latest results on multiplicity dependence of strange and mult…
The ALICE experiment studies Pb-Pb collisions at the LHC in order to investigate the properties of the hot and dense QCD matter at extreme energy densities. Recent results from ALICE in identified particle flow allow for the exploration of the collective properties of the medium created in heavy-ion collisions. In this paper, I give special attention to strange and charm particles which probe the medium differently and thus provide new constraints for the study of its properties. The paper covers results on elliptic flow for pion, kaon, kzero, antiproton, phi, lambda, xi, omega, dplus, dzero a…
We present a new method for detection of multiply charmed baryons via their decays into strange baryons, using `strangeness tracking'. This method makes use of the state-of-the-art upgraded silicon detectors in ALICE during Runs 3, 4 and beyond will enable the novel possibility of tracking strange hadrons directly before they decay, leading to a very significant improvement in impact-parameter resolution. In this work, we will discuss how this new technique will be crucial to distinguish secondary strange baryons originating from charm decays from primary strange baryons. This is a particularl…
Multi-strange baryons are of particular interest in the understanding of particle production mechanisms, as their high strangeness content makes them susceptible to changes in the hadrochemistry of the colliding systems. In ALICE, these hyperons are reconstructed via the detection of their weak decay products, which are identified through their measured ionisation losses and momenta in the Time Projection Chamber. The production rates of charged $Ξ$ and $Ω$ baryons in proton-proton (pp), proton-lead (p-Pb) and lead-lead (Pb-Pb) collisions are reported as a function of $p_{\mathrm{T}}$. A direc…
Heavy quarks are effective probes of the properties of the QGP created in ultra-relativistic heavy-ion collisions. The ALICE Collaboration measured the non-strange D-meson production in Pb--Pb collisions at $\sqrt{s_{\rm NN\,}}=5.02$ TeV. The in-medium energy loss can be studied via the nuclear modification factor measurement. The measurement of the D-meson elliptic flow, $v_2$, allows us to investigate the participation of the heavy quarks in the collective expansion of the system at low momentum and their possible thermalization in the medium. Furthermore, the Event-Shape Engineering techniq…
The production of Ξ$^{-}$ and Ω$^{-}$ baryons and their anti-particles in pp, p-Pb and Pb-Pb collisions has been measured by the ALICE Collaboration. These hyperons are reconstructed via the detection of their charged weak-decay products, which are identified through their measured ionisation losses and momenta in the ALICE Time Projection Chamber. Comparing the production yields in Pb-Pb and pp collisions, a strangeness enhancement has been measured and found to increase with the centrality of the collision and with the strangeness content of the baryon; moreover, in the comparison with simil…
The production of $Ξ^{-}$ and $Ω^{-}$ baryons and their anti-particles in Pb-Pb and pp collisions at $\sqrt{s_{NN}}$ = 2.76 TeV has been measured by the ALICE collaboration. The transverse momentum spectra at mid-rapidity (|y| < 0.5) in pp and Pb-Pb collisions for five centrality intervals have been compared with model predictions. Hyperon yields and spectra in Pb-Pb collisions, normalized to the corresponding measurements in pp at the same centre-of-mass energy, allow the study of the strangeness enhancement and the nuclear modification factor as a function of the transverse momentum ($p_{T}$…
Measurements of spectra of identified particles produced in jets represent an important tool for understanding the interplay of various hadronisation mechanisms which contribute to particle production in the hot and dense medium created in ultra-relativistic heavy-ion collisions. In this contribution, we present the measurements of the pT spectra of Λ baryons and K0S mesons produced in charged jets in Pb--Pb collisions at sqrt(sNN) = 2.76 TeV and in p--Pb collisions at sqrt(sNN) = 5.02 TeV. The results are obtained with the ALICE detector at the LHC, exploiting the excellent particle identific…
Hadronic resonances are unique tools to investigate the interplay of re-scattering and regeneration effects in the hadronic phase of heavy-ion collisions. As the $ϕ$ meson has a longer lifetime compared to other resonances, it is expected that its production will not be affected by regeneration and re-scattering processes. Measurements in small collision systems such as proton-proton (pp) collisions provide a necessary baseline for heavy-ion data and help to tune pQCD inspired event generators. Given that the $ϕ$ is a bound state of strange-antistrange quark pair (s$\bar{\rm{s}}$), measurement…
The ALICE experiment at the LHC has measured the production of strange hadrons and resonances in Pb-Pb and pp collisions at unprecedented high beam energies. The study of strange hadrons and resonances helps us to understand the properties of the medium created in the heavy-ion collisions and its evolution. We present the yields ($dN/dy$) at mid-rapidity for strange hadrons ($Λ$, $Ξ^{-}$, $Ω^{-}$, their anti-particles and $K_{S}^{0}$) and resonances ($ϕ$ and $K^{*0}$) for several collision centrality intervals. The results from Pb-Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV are presented and c…
The main goal of the ALICE experiment is to study the physics of strongly interacting matter, focusing on the properties of the quark-gluon plasma (QGP). The relative production of strange hadrons with respect to non-strange hadrons in heavy-ion collisions was historically considered as one of the signatures of QGP formation. However, the latest results in proton-proton (pp) and proton-lead (p-Pb) collisions have revealed an increasing trend in the yield ratio of strange hadrons to pions with the charged-particle multiplicity in the event, showing a smooth evolution across different collision …
Studies of jet production can provide information about the properties of the hot and dense strongly interacting matter created in ultra-relativistic heavy-ion collisions. Specifically, measurement of strange particles in jets may clarify the role of fragmentation processes in the anomalous baryon to meson ratio at intermediate particle pT that was observed in PbPb and, to a lesser extent, in pPb collisions. In this contribution, measurements of the pT spectra of Lambda and Antilambda baryons and K0s mesons produced in association with charged jets in PbPb collisions at sqrt(sNN)=2.76 TeV and …
A Large Ion Collider Experiment (ALICE) is the dedicated heavy-ion experiment at the Large Hadron Collider (LHC). In addition to its heavy-ion physics program, it also has a rich proton-proton physics program benefiting from a detector with a low momentum cut-off (pT about 50 MeV/c) and a small material budget (about 11% of a radiation length until the outer wall of the main tracking detector, the Time-Projection Chamber). ALICE has excellent means of particle identification (PID) with methods ranging from specific energy loss and time of flight to transition and Cherenkov radiation. The good …
The production of strange~($K^0_S$, $Λ$) and multi-strange~($Ξ$ and $Ω$) hadrons in jets and underlying events in \pp and \pPb collisions is studied with ALICE at the LHC. Transverse momentum ($p_\rm{T}$) differential density distribution of particles produced in a jet is compared to that of inclusive particle production and that in underlying events. The particle yield ratios of $Λ/K^0_S$ and $Ξ/Λ$ as a function of $p_\rm{T}$ are also investigated in jets and underlying events.The production of the multi-strange hadrons, $Ξ$ and $Ω$, and the corresponding ratio in jets and underlying events a…
The study of identified particle production as a function of transverse momentum ($p_{\text{T}}$) and event multiplicity in proton-proton (pp) collisions at different center-of-mass energies ($\sqrt{s}$) is a key tool for understanding similarities and differences between small and large collisions systems. We report on the production of $π^{\pm}$, $K^{\pm}$, $K^{0}_{S}$, $p (\bar{p})$, $Λ(\barΛ)$, $Ξ^{\pm}$ and $Ω^{\pm}$ measured in pp collisions in a wide range of center-of-mass energies with ALICE. The multiplicity dependence of identified particle yields is presented for $\sqrt{s} = \textr…
Studies of light hadron and nuclei production are fundamental to characterize the hot and dense fireball created in ultra-relativistic heavy ion collisions and to investigate hadronisation mechanisms at the LHC. Observables investigated as a function of the charged particle multiplicity in proton-proton and proton-lead collisions have shown features not expected and qualitatively similar to what has been observed in larger size colliding systems. The ALICE experiment, exploiting its excellent tracking and PID capabilities, has performed an extensive and systematic study of strange and non-stra…
In these proceedings, measurements of angular correlations between hadron pairs in pp collisions obtained by the ALICE experiment at the LHC are presented and compared with phenomenological predictions. Correlations between particles carrying the same and opposite quantum numbers are studied to understand the hadron production mechanism, and the difference between same-sign and opposite-sign correlations is used to probe charge-dependent effects in particle production. Correlation measurements dominated by minijet fragmentation agree well with the models, but other results, in particular corre…
ALICE is the dedicated heavy-ion experiment at the Large Hadron Collider. The experiment has also a broad program of QCD measurements in proton-proton (pp) collisions, which have two-fold interest: the study of particle production at the highest energy frontier, and the definition of references for the corresponding measurements in the upcoming Pb-Pb run. We present the first results on the pseudorapidity and transverse-momentum dependence of charged particle production in pp collisions at LHC energies, on the anti-p/p ratio and on the Bose-Einstein particle correlations. As an outlook, we rep…
A first measurement of time-reversal (T) asymmetries that are not also CP asymmetries has been recently achieved by the BaBar collaboration. We analyze the measured asymmetries in the presence of direct CP violation, CPT violation, wrong strangeness decays and wrong sign semileptonic decays. We note that the commonly used S_{ψK} and C_{ψK} parameters are CP-odd, but have a T-odd CPT-even part and a T-even CPT-odd part. We introduce parameters that have well-defined transformation properties under CP, T and CPT. We identify contributions to the measured asymmetries that are T conserving. We exp…
A measurement of the multi-strange $Ξ^-$ and $Ω^-$ baryons and their antiparticles by the ALICE experiment at the CERN Large Hadron Collider (LHC) is presented for inelastic proton-proton collisions at centre of mass energy of 7 TeV. The transverse momentum ($p_{\rm T}$) distributions were studied at mid-rapidity (|y| < 0.5) in the range of 0.6 < $p_{\rm T}$ < 8.5 GeV/$c$ for $Ξ^-$ and $Ξ^+$ baryons, and in the range of 0.8 < $p_{\rm T}$ < 5 GeV/$c$ for $Ω^-$ and $Ω^+$. Baryons and antibaryons were measured as separate particles and we find that the baryon to antibaryon ratio of both particle …
A Large Ion Collider Experiment (ALICE) is one of the four big experiments installed at the CERN Large Hadron Collider (LHC) and it is suited to study pp, p--Pb and Pb--Pb collisions. It aims to study the strongly interacting matter at extreme conditions of temperature and density under which the quarks decouple to form a new state of matter called the Quark Gluon Plasma (QGP). Such a state of matter existed a few microseconds after the Big Bang in which the universe was created. Several experimental observables, sensitive to the evolution of the system after the nuclear collisions, reveal imp…
Today the B-factories BaBar and Belle have accumulated largest samples of tau-tau events and are competing to be called tau-factories. Among the problems to be tested and measurements to be done by BaBar and Belle are check of CP and CPT invariance in tau decays, measurement of strange and non-strange spectral functions, extraction of mass of strange quark and |V_us|, searches for lepton flavor violation processes. In this paper, the latest results in tau physics by these two experiments and measurements to be done within next few years are reviewed.
Particle ratios provide insight into the hadrochemistry of the event and the mechanisms for particle production. In Pb-Pb collisions the relative multi-strange baryon yields exhibit an enhancement with respect to pp collisions, whereas the short-lived K$^{*0}$ resonance is suppressed in the most central events due to re-scattering of its decay daughter particles. Measurements in p-Pb allow us to investigate the development of these effects as a function of the system size. We report comprehensive results on light-flavor hadron production measured with the ALICE detector in p-Pb collisions at $…
The excellent capabilities of the ALICE experiment for particle identification allow to measure the identified hadron production in a wide range of transverse momentum. In this work we present some results on identified particle spectra, strange particle production and particle contents measured in pp collisions at \sqrt{s} = 0.9, 2.76 and 7 TeV. The results are compared with Monte Carlo event generators predictions.
The production rates and the transverse momentum distribution of strange hadrons at mid-rapidity ($\ |y\ | < 0.5$) are measured in proton-proton collisions at $\sqrt{s}$ = 13 TeV as a function of the charged particle multiplicity, using the ALICE detector at the LHC. The production rates of $\rm{K}^{0}_{S}$, $Λ$, $Ξ$, and $Ω$ increase with the multiplicity faster than what is reported for inclusive charged particles. The increase is found to be more pronounced for hadrons with a larger strangeness content. Possible auto-correlations between the charged particles and the strange hadrons are eva…
Some recent $τ$-physics results are presented from the BaBar and Belle experiments at the SLAC and KEK B factories, which produce copious numbers of $τ$-lepton pairs. Measurements of the tau mass and lifetime allow to test lepton universality and CPT invariance, while searches for lepton-flavour violation in tau decays are powerful ways to look for physics beyond the Standard Model. In semihadronic, non-strange tau decays, the vector hadronic final state is particularly important in helping determine the hadronic corrections to the anomalous magnetic moment of the muon, while studies of strang…
Event-by-event fluctuations of conserved charges - such as electric charge, strangeness, and baryon number - in ultrarelativistic heavy-ion collisions provide insight into the properties of the quark-gluon plasma and the QCD phase diagram. They can be related to the higher moments of the multiplicity distributions of identified particles, such as the $Λ$ baryon which carries both strangeness and baryon number and is thus of particular interest. We present the first measurement of net-$Λ$ fluctuations in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}} = 5.02$ TeV as a function of centrality and the…
In November 2010 the ALICE experiment at CERN has collected the first Pb--Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV produced by the LHC. A first characterization of the hot and dense state of matter produced in this new energy domain became available shortly after the run. In this paper we present the results on charged-particle multiplicity, Bose-Einstein correlations, elliptic flow and their dependence on the collision centrality. Results from first measurements of strange and identified particle production and suppression of high-momentum hadrons with respect to $pp$ collisions are also r…
The study of identified particle production in proton-proton (pp) collisions as a function of center-of-mass energy ($\sqrt{s}$) and event charged-particle multiplicity is a key tool for understanding similarities and differences between small and large collision systems. We report on new measurements of the production of identified particles and their dependence on multiplicity and $\sqrt{s}$. Latest results for light flavor hadrons, comprising $π^{\pm}$, $\mathrm{K}^{\pm}$, ${\rm p}(\rm \bar{p})$, single-strange ($\mathrm{K_{S}^{0}}$, $\barΛ$, and $Λ$), multi-strange ($Ξ^{-}$, $\overlineΞ^{+…
The ALICE experiment features multiple particle identification systems. The measurement of the identified charged hadron $p_{t}$ spectra in proton-proton collisions at $\sqrt{s}=900$ GeV will be discussed. In the central rapidity region ($|η|<0.9$) particle identification and tracking are performed using the Inner Tracking System (ITS), which is the closest detector to the beam axis, the Time Projection Chamber (TPC) and a dedicated time-of-flight system (TOF). Particles are mainly identified using the energy loss signal in the ITS and TPC. In addition, the information from TOF is used to iden…
The study of strange hadronic resonances in pp collisions contributes to the study of strangeness production in small systems. Measurements in pp collisions constitute a reference for the study in larger colliding systems and provide constraints for tuning QCD-inspired event generators. Since the lifetimes of short-lived resonances such as $\mathrm{K}^{*}(892)^{\pm}$ ($τ\sim 4$ fm/\textit{c}) are comparable with the lifetime of the fireball produced in heavy-ion collisions, regeneration and rescattering effects can modify the measured yield, especially at low transverse momentum. The first res…
Exploring Collective Effects in Small Collision Systems via Light-Flavour Particle Production in High-Multiplicity pp Collisions at $\sqrt{s}=$ 13 TeV in ALICE
