The NA61/SHINE Experiment at the CERN SPS

NA61/SHINE实验在CERN SPS能量下的多重数与净电荷涨落结果

NA61/SHINE results on multiplicity and net-charge fluctuations at CERN SPS energies

NA61/SHINE实验分析CERN SPS能量下Ar+Sc最中心碰撞的多重数与净电荷涨落，经高阶累积矩比值计算并校正探测器偏差后，对比不同能量、p+p相互作用及模型预测，给出能量依赖关系的最终结果。

Methods to study event-by-event fluctuations in the NA61/SHINE experiment at the CERN SPS

Theoretical calculations locate the critical point of strongly interacting matter (CP) at energies accessible at the CERN SPS. Event-by-event transverse momentum and multiplicity fluctuations are considered as one of the most important tools to search for the CP. Pilot studies of the energy dependence and the system size dependence of both $p_T$ and multiplicity fluctuations were performed by the NA49 experiment. The NA61/SHINE ion program is a continuation of these efforts. After briefly recalling the essential NA49 results on fluctuations we will discuss the technical methods (removing Non-T…

NA61/SHINE at the CERN SPS: plans, status and first results

The NA61/SHINE experiment aims to discover the critical point of strongly interacting matter and study properties of the onset of deconfinement. It also to performs precise hadron production measurements for the neutrino and cosmic rays experiments. These goals will be achieved by measurements of hadron production properties in nucleus-nucleus, proton-proton and proton-nucleus interactions as a function of collision energy and size of the colliding nuclei, as well as pion-nucleus interactions. This contribution summarises the arguments of the ion program as well as presents the first physics r…

Open charm measurements in NA61/SHINE at CERN SPS

The measurements of open charm production was proposed as an important tool to investigate the properties of hot and dense matter formed in nucleus-nucleus collisions as well as to provide the means for model independent interpretation of the existing data on $\text{J}/ψ$ suppression. Recently, the experimental setup of the NA61/SHINE experiment was supplemented with a Vertex Detector which was motivated by the importance and the possibility of the first direct measurements of open charm meson production in heavy ion collisions at SPS energies. First test data taken in December 2016 on Pb+Pb c…

Results on system size dependence of strangeness production in the CERN SPS energy range from NA61/SHINE

NA61/SHINE is a multipurpose fixed-target facility at the CERN Super Proton Synchrotron. The main goals of the NA61/SHINE strong interactions program are to discover the critical point of strongly interacting matter and study the properties of the onset of deconfinement. To reach these goals, hadron production measurements are performed in the form of a two-dimensional scan by varying collision energy and system size. The Collaboration has recently finished data acquisition for its original program on strong interactions, accumulating broad data samples on hadron production in various systems …

重离子物理在CERN SPS H2：NA35、NA49和NA61/SHINE（附个人回忆）

Heavy-ion physics at the CERN SPS H2: NA35, NA49 and NA61/SHINE (with personal recollections)

综述了NA35、NA49和NA61/SHINE实验在CERN SPS H2束流线上40年重离子研究的成果，包括QGP的发现及高能核碰撞图谱的建立。

Higher order moments of net-charge and multiplicity distributions in p+p interactions at SPS energies from NA61/SHINE

NA61/SHINE at the CERN SPS is a fixed-target experiment pursuing a rich physics program including measurements for heavy ion, neutrino and cosmic ray physics. The main goal of the ion program is to study the properties of the onset of deconfinement and to search for the signatures of the critical point. A specific property of the critical point, the increase in the correlation length, makes fluctuations its basic signal. Higher order moments of suitable observables are of special interest as they are more sensitive to the correlation length than typically studied second order moments. In this …

Open charm measurements with the NA61/SHINE experiment at the CERN SPS

The strong interactions programme of the NA61/SHINE experiment at the CERN SPS has been extended through the use of new silicon Vertex Detector, which allows for reconstructing open charm particles. The detector was designed to identify those particles by means of a precise reconstruction of their primary and secondary vertices. An initial version of the Vertex Detector, called SAVD (Small Acceptance Vertex Detector), was installed end of 2016. It was operated in a Pb+Pb calibration beam time in 2016, and with Xe+La in 2017. A further Pb+Pb beam time is scheduled for late 2018. The first indic…

Transverse Momentum and Multiplicity Fluctuations in Ar+Sc Collisions at the CERN SPS from NA61/SHINE

The NA61/SHINE experiment aims to discover the critical point of strongly interacting matter and study the properties of the onset of deconfinement. For these goals a scan of the two dimensional phase diagram ($T$-$μ_{B}$) is being performed at the SPS by measurements of hadron production in proton-proton, proton-nucleus and nucleus-nucleus interactions as a function of collision energy and system size. In this contribution preliminary results on transverse momentum and multiplicity fluctuations expressed in terms of strongly intensive quantities from the Ar+Sc energy scan will be presented. T…

Fluctuations and correlations in nucleus-nucleus collisions observed by NA61/SHINE at CERN SPS energies

The NA61/SHINE strong interaction programme aims to explore the phase diagram of the strongly interacting matter. The main physics goals are the study of the onset of deconfinement and the search for the critical point of the strongly interacting matter. These goals are pursued by performing a scan in beam momentum (13A -- 158A GeV/c) and size of colliding system (p+p, p+Pb, Be+Be, Ar+Sc, Xe+La, Pb+Pb). This contribution presents new results on system size and energy dependence of multiplicity and net-charge fluctuations measured with higher-order moments of these distributions. Also, new resu…

Transverse momentum and multiplicity fluctuations in Ar+Sc collisions at the CERN SPS from NA61/SHINE

The NA61/SHINE experiment aims to discover the critical point of strongly interacting matter and study the properties of the onset of deconfinement. For these goals a scan of the two dimensional phase diagram ($T$-$μ_{B}$) is being performed at the SPS by measurements of hadron production in proton-proton, proton-nucleus and nucleus-nucleus interactions as a function of collision energy and system size. In this contribution preliminary results on transverse momentum and multiplicity fluctuations expressed in terms of strongly intensive quantities from the Ar+Sc energy scan will be presented. T…

Open charm measurements at CERN SPS energies with the new Vertex Detector of the NA61/SHINE experiment

The study of open charm meson production provides an efficient tool for detailed investigations of the properties of hot and dense matter formed in nucleus-nucleus collisions. The interpretation of the existing data from the CERN SPS suffers from a lack of knowledge on the total charm production rate. To overcome this limitation the heavy-ion programme of the NA61/SHINE experiment at CERN SPS has been expanded to allow for precise measurements of particles with a short lifetime. A new Small Acceptance Vertex Detector (SAVD) was designed and constructed to meet the challenges of open charm meas…

NA61/SHINE在CERN SPS上寻找QCD临界点

Search for the QCD critical point by NA61/SHINE at the CERN SPS

NA61/SHINE利用二维扫描数据，通过分析横动量空间中粒子数涨落及阶乘矩标度行为，系统寻找QCD临界点。

System size and energy dependence of proton rapidity spectra from NA61/SHINE at the CERN SPS

NA61/SHINE is an experiment at the CERN Super Proton Synchrotron. The main goals of the experiment are the search for the critical point of strongly interacting matter and the study of the properties of the onset of deconfinement. To reach these goals, the two-dimensional scan in beam momentum ($13A-150A$ GeV/$c$) and system size ($p$+$p$, Be+Be, Ar+Sc, Xe+La, Pb+Pb) was performed. In the final stage of the collision, the spectra of protons are only weakly affected by the effects of resonance decays and rescattering due to their large mass. Thus, proton rapidity distribution is particularly se…

NA61/SHINE results on fluctuations and correlations in p+p and Be+Be interactions at CERN SPS energies

The aim of the NA61/SHINE strong interaction program is to explore the phase diagram of strongly interacting matter. The main physics goals are the study of the onset of deconfinement and the search for the critical point of strongly interacting matter. These goals are pursued by performing a beam momentum (13$A$ - 158$A$ GeV/c) and system size (p+p, p+Pb, Be+Be, Ar+Sc, Xe+La) scan. This contribution presents results on transverse momentum and multiplicity fluctuations from the Be+Be and p+p energy scan. Also, results on two-particle correlations in pseudorapidity and azimuthal angle obtained …

Energy dependence of identified hadron spectra and event-by-event fluctuations in p+p interactions from NA61/SHINE at the CERN SPS

NA61/SHINE at the CERN SPS is a fixed-target experiment pursuing a rich physics program including measurements for heavy ion, neutrino and cosmic ray physics. The main goal of the ion program is to explore the most interesting $T, mu_{B}$ region of the phase diagram of strongly interacting matter. We plan to study the properties of the onset of deconfinement and to search for the signatures of the critical point. The search is performed by varying collision energy (13A-158A GeV/c) and system size (p+p, Be+Be, Ar+Ca, Xe+La). Thanks to its large acceptance and excellent particle identification c…

CERN SPS上NA61/SHINE测量的Ar+Sc碰撞中带电介子相对中性介子的增强产生

Enhanced production of charged over neutral kaons in Ar+Sc collisions measured by NA61/SHINE at CERN SPS

NA61/SHINE合作组测量了11.9 GeV下Ar+Sc碰撞中K介子产生，发现带电K介子比中性K介子高(18.4±6.1)%，现有包含同位旋破缺效应的强子产生模型无法解释该结果。

Multiplicity fluctuations in Ar+Sc collisions at the CERN SPS from NA61/SHINE

Multiplicity fluctuations were investigated in Ar+Sc collisions at 13A, 19A, 30A, 40A, 75A, 150A GeV/c using the NA61/SHINE detector at the SPS. Centrality selection is based on the nucleon-spectator energy in the forward hemisphere as measured by the Projectile spectator detector. Preliminary results on the scaled variance ω and the strongly intensive measure Ω were obtained for the multiplicity distribution of all, negatively and positively charged hadrons. Results are discussed and compared with p+p results and Pb+Pb data of NA49 and EPOS 1.99 simulations.

Charm Program of NA61/SHINE: Motivation and Measurements

Recently, the NA61/SHINE experiment at the CERN SPS has extended its program on physics of strong interactions by measurements of charm hadron production in nucleus-nucleus collisions. This charm program is here briefly summarized.

NA49 and NA61/SHINE experiments: results and perspectives

The Super Proton Synchrotron (SPS) covers one of the most interesting regions of the QCD phase diagram $(T - μ_B)$. On the one hand there are indications that the energy threshold for deconfinement is reached already at low SPS energies. On the other hand theoretical calculations locate the QCD critical end-point at energies accessible at the SPS. In this paper the NA49 signatures of the onset of deconfinement are presented. Results are shown on pion production, the kaon to pion ratio, slopes of transverse mass spectra ("temperature"), and event-by-event particle ratio fluctuations versus coll…

NA61/SHINE ion program

The Super Proton Synchrotron (SPS) at CERN covers one of the most interesting regions of the phase diagram (T - μ_{B}) of strongly interacting matter. The study of central Pb+Pb collisions by NA49 indicate that the threshold for deconfinement is reached already at the low SPS energies. Theoretical considerations predict a critical point of strongly interacting matter at energies accessible at the SPS. The NA61/SHINE experiment, a successor of the NA49 project, will study hadron production in p+p, p+A, h+A, and A+A reactions at various energies. The broad physics program includes the investigat…

Onset of Deconfinement and Critical Point - Future Ion Program at the CERN SPS

A new experimental program to study hadron production in collisions of nuclei at the CERN SPS is presented. The program will focus on measurements of fluctuations and long correlations with the aim to identify properties of the onset of deconfinement and search for the critical point of strongly interacting matter.

Recent results from the search for the critical point of strongly interacting matter at the CERN SPS

Recent searches at the CERN SPS for evidence of the critical point of strongly interacting matter are discussed. Experimental results on theoretically expected signatures, such as event-to-event fluctuations of the particle multiplicity and the average transverse momentum as well as intermittency in particle production are presented.

Recent results from the search for the critical point of strongly interacting matter at the CERN SPS

Recent searches at the CERN SPS for evidence of the critical point of strongly interacting matter are discussed. Experimental results on theroretically expected signatures, such as event-to-event fluctuations of the particle multiplicity and the average transverse momentum as well as intermittency in particle production are presented.

The Old New Frontier: Studying the CERN-SPS Energy Range with NA61/SHINE

With the Large Hadron Collider entering its third year of granting us insight into the highest collision energies to date, one should nevertheless keep in mind the unexplored physics potential of lower energies. A prime example here is the NA61/SHINE experiment at the CERN Super Proton Synchrotron. Using its large-acceptance hadronic spectrometer, SHINE aims to accomplish a number of physics goals: measuring spectra of identified hadrons in hadron-nucleus collisions to provide reference for accelerator neutrino experiments and cosmic-ray observatories, investigating particle properties in the …

Search for the critical point by the NA61/SHINE experiment

NA61/SHINE is a fixed target experiment operating at CERN SPS. Its main goals are to search for the critical point of strongly interacting matter and to study the onset of deconfinement. For these goals a scan of the two dimensional phase diagram ($T$-$μ_{B}$) is being performed at the SPS by measurements of hadron production in proton-proton, proton-nucleus and nucleus-nucleus interactions as a function of collision energy. In this paper the status of the search for the critical point of strongly interacting matter by the NA61/SHINE Collaboration is presented including recent results on proto…

NA49/NA61: results and plans on beam energy and system size scan at the CERN SPS

This paper presents results and plans of the NA49 and NA61/SHINE experiments at the CERN Super Proton Synchrotron concerning the study of relativistic nucleus-nucleus interactions. First, the NA49 evidence for the energy threshold of creating quark-gluon plasma, the onset of deconfinement, in central lead-lead collisions around 30A GeV is reviewed. Then the status of the NA61/SHINE systematic study of properties of the onset of deconfinement is presented. Second, the search for the critical point of strongly interacting matter undertaken by both experiments is discussed. NA49 measured large fl…

Dileptons and Photons at the CERN SPS

The paper reviews all experimental results on dileptons with invariant mass m < 3 GeV/c$^2$ and real photons obtained from the CERN SPS heavy-ion program with S and Pb beams, together with the current attempts to understand them.

Pion production in p+p interactions and Be+Be collisions at the CERN SPS energies

Evidence for the onset of deconfinement in central Pb+Pb collisions was reported by NA49 in fixed target measurements at beam momentum 30A GeV/c. This observation motivated the NA61/SHINE program started in 2009 at the CERN SPS, which, in particular, aims to study properties of the onset of deconfinement by measurements of hadron production in proton-proton, proton-nucleus and nucleus-nucleus collisions. This contribution presents spectra of charged pions produced in p+p interactions and $^7$Be+$^9$Be collisions at 20A-158A GeV/c beam momentum. The NA61/SHINE results are compared with the corr…

Recent results from NA61/SHINE on spectra and correlations in p+p and Be+Be interactions at the CERN SPS

The problem of pinning down the critical point of strongly interacting matter still puzzles the community. One of the answers suspected to emerge in the near future will surely come from NA61/SHINE - a fixed-target experiment aiming to discover the critical point as well as to study the properties of the onset of deconfinement. This goal will be pursued by obtaining precise data on hadron production in proton-proton, proton-nucleus and nucleus-nucleus interactions in a wide range of system size and collision energy. This contribution presents new results on inclusive spectra of identified hadr…

Energy dependence of fluctuations in p+p and Be+Be collisions from NA61/SHINE

The main aims of the NA61/SHINE experiment are to discover the critical point of strongly interacting matter and to study properties of the onset of deconfinement. For this goal a two dimensional scan of the phase diagram (T-$μ_{B}$) is being performed at the SPS with measurements of hadron production in proton-proton, proton-nucleus and nucleus-nucleus interactions as a function of collision energy and system size. It is expected that fluctuations of various dynamical quantities will increase close to the critical point. In this contribution recent results of measurements of fluctuations in p…

Energy dependence of {\rm K}$^0_{\rm S}$ and hyperon production at CERN SPS

Recent results on K$^0_{\rm S}$ and hyperon production in Pb-Pb collisions at 40 and 158 $A$ GeV/$c$ beam momentum from the NA57 experiment at CERN SPS are presented. Yields and ratios are compared with those measured by the NA49 experiment, where available. The centrality dependence of the yields and a comparison with the higher collision energy data from RHIC are discussed.

Study of the phase diagram of strongly interacting matter in the NA61/SHINE experiment

NA61/SHINE (SPS Heavy Ion and Neutrino Experiment) is a fixed target experiment located at the CERN SPS. Its strong interactions program is devoted to study properties of the phase diagram of strongly interacting matter. For this goal the two-dimensional scan is performed by measurements of hadron production properties as a function of collision energy (13A - 158A GeV/$c$) and system size (p+p, p+Pb, Be+Be, Ar+Sc, Xe+La, Pb+Pb). This contribution presents new results on the onset of deconfinement - the transition between the state of hadronic matter and the quark-gluon plasma. Also, new result…

Searching for the critical point of strongly interacting matter in nucleus-nucleus collisions at CERN SPS

The search for experimental signatures of the critical point (CP) of strongly interacting matter is one of the main objectives of the NA61/SHINE experiment at CERN SPS. In the course of the experiment, a beam momentum and system size scan is performed. Local proton density fluctuations in transverse momentum space represent an order parameter of the chiral phase transition and are expected to scale according to a universal power-law in the vicinity of the CP; we probe their behavior through an intermittency analysis of the proton second scaled factorial moments (SSFMs) in transverse momentum s…

Prospects for the NA60+ experiment at the CERN SPS

A new heavy-ion experiment on fixed target, NA60+, has been proposed at the CERN SPS for data taking in the next years. Its main goals will be focused on precision studies of thermal dimuons, heavy quark and strangeness production in Pb-Pb collisions at center-of-mass energies ranging from 5 to 17 GeV, which will provide a unique opportunity to investigate the region of the QCD phase diagram at high baryochemical potential ($μ_B \sim 200-400$~MeV). The key points of the NA60+ very broad and ambitious physics program will be described.

CERN SPS上NA61/SHINE实验中的Λ超子横向极化：可行性研究

Lambda transverse polarization in NA61\SHINE at the CERN SPS: feasibility studies

本研究针对CERN SPS的NA61/SHINE实验，分析了磁场与探测器接收度对Λ超子横向极化测量的影响，发现磁场进动的影响比接收度偏差小一个量级，验证了该实验观测极化信号的可行性。

未来设施：CERN SPS

Future facilities: the CERN SPS

本文综述CERN SPS重离子物理项目的现状与未来，聚焦硬探针和电磁探针，并介绍NA61/SHINE及拟议NA60+实验的成果与目标。

New Results from the Cosmic-Ray Program of the NA61/SHINE facility at the CERN SPS

The NA61/SHINE experiment at the SPS accelerator at CERN is a unique facility for the study of hadronic interactions at fixed target energies. The data collected with NA61/SHINE is relevant for a broad range of topics in cosmic-ray physics including ultrahigh-energy air showers and the production of secondary nuclei and anti-particles in the Galaxy. Here we present an update of the measurement of the momentum spectra of anti-protons produced in $π^-$+C interactions at 158 and 350 GeV/c and discuss their relevance for the understanding of muons in air showers initiated by ultrahigh-energy cosmi…

Recent results from NA61/SHINE

This paper briefly presents the NA61/SHINE facility at the CERN SPS and its measurements motivated by physics of strong interactions, neutrinos and cosmic rays.

Recent results from NA61/SHINE and NA49

Preliminary results on particle spectra and fluctuations in inelastic p+p interactions measured by NA61/SHINE at the CERN SPS are presented and its future ion program is discussed. We also show results on the excitation functions of event-by-event particle ratio fluctuations in central Pb+Pb collisions from NA49 using a novel approach. We found a dependence of the results on phase space coverage which appears to explain the reported difference between measurements of NA49 and those of STAR in central Au+Au collisions.

Systematic Study of Hadronic Observables in Nucleus Nucleus Collisions at CERN SPS

The possible transition of nuclear matter to a deconfined phase in relativistic nucleus-nucleus collisions is explored by a systematic variation of the collision system by means of system size, beam energy and centrality of the collision all measured within the same experiment NA49 at the CERN SPS. The investigation takes advantage of the large number of hadronic observables covered over a wide phase space by the acceptance of the NA49 TPCs.

Hyperon production at CERN SPS energies

New experimental results of NA49 on hyperon production in central Pb+Pb collisions at the SPS energies are presented. In particular, measurements of $Λ$ production at 30 A$\cdot$GeV and $Ξ$ and $Ω$ production at 40 A$\cdot$GeV are shown. Transverse mass spectra and rapidity distributions of hyperons at different energies are compared. The energy dependence of the particle yields and ratios is discussed.

Open charm measurements at CERN SPS energies with the new Vertex Detector of the NA61/SHINE experiment

The heavy-ion programme of the NA61/SHINE experiment at the CERN SPS has been expanded to allow precise measurements of exotic particles with short lifetime. The study of open charm meson production is a sensitive tool for new detailed investigations of the properties of hot and dense matter formed in nucleus-nucleus collisions. In particular, it offers new possibilities for studies of such phenomena as in-medium parton energy loss and quarkonium dissociation and possible regeneration, thus providing new information to probe deconfinement. A new high resolution Vertex Detector was designed for…

High pt Measurements at the CERN SPS

The current experimental situation concerning high pt observables at the CERN SPS is reviewed. Recent data from the NA45, NA49 and NA57 collaborations are discussed and compared to earlier measurements by WA98 and NA45 at the same center-of-mass energies, as well as to measurements at the higher energies by the RHIC experiments. The observables include new p+p, A+A spectra, nuclear modification factors (R_AA, R_CP), two particle azimuthal correlations, and baryon to meson ratios at moderately high pt. Generally, the interpretation of the SPS data suffers from the lack of reliable baseline meas…

Energy scan of correlations in p+p and Be+Be from NA61/SHINE

The existence of the critical point (CP) of strongly interacting matter is still an open problem. An extensive strong interactions program including a search of the CP and the study of the onset of deconfinement was started by the NA61/SHINE experiment at the CERN SPS. A two dimensional scan of the phase diagram scan is performed to search for the CP and to shed light on the phase transition region. This program includes studies of hadron production in proton-proton, proton-nucleus and nucleus-nucleus interactions measured in a wide range of colliding energy and system size. Correlations betwe…

Recent results from NA61/SHINE

NA61/SHINE at the CERN SPS is a fixed-target experiment pursuing a rich physics program including measurements for heavy ion, neutrino and cosmic ray physics. The main goal of the strong interactions program is to study the properties of the onset of deconfinement and to search for the signatures of the critical point. In this contribution the latest NA61/SHINE results on particle spectra as well as on fluctuations and correlations from p+p, Be+Be, and Ar+Sc energy scans will be presented. The NA61 measurements will be compared with world data and with model predictions.

Anti-nuclei and nuclei production in Pb+Pb collisions at CERN SPS energies

We present new results on production of 3He and t obtained by the NA49 experiment in 20A, 30A, 40A and 80A GeV central Pb+Pb collisions at the CERN SPS. Transverse mass spectra and rapidity distributions for clusters measured over a large phase space domain are discussed. We observe a weak dependence of the mid-rapidity t/3He ratio on collision energy at SPS. The energy dependence of the total yield for 3He is remarkably reproduced by a statistical hadron gas model. A gradual decrease of the coalescence parameter B3 for 3He with $\sqrt {s_{NN}}$ is observed.In addition, a measurement of the yi…

Status and plans of the ion program of NA61 at the CERN SPS

The NA61/SHINE at the CERN SPS is a new experiment to study hadron production in p+p p+A, h+A and A+A interactions. The main goal of the NA61 ion program is to explore the phase diagram (T - mu_B) of strongly interacting matter. In particular, we plan to study the properties of the onset of deconfinement and to search for the signatures of the critical point. A two-dimensional scan of the phase diagram will be performed by varying the energy (13A-158A GeV) and system size (p+p, Be+Be, Ar+Ca, Xe+La) of collisions. This paper summarizes the status and plans of the NA61/SHINE ion program. In part…

New results on fluctuations and correlations from the NA61/SHINE experiment at the CERN SPS

The exploration of the QCD phase diagram is the most important task of present heavy ion experiments. In particular, we want to study the phase transition from hadronic to partonic matter and look for the critical point (CP) of strongly interacting matter. Fluctuations and correlations in kinematic characteristics and particle yields may help to locate the CP (in analogy to enlarged fluctuations due to critical opalescence close to a CP in a liquid/gas transition). The strong interactions program of the NA61/SHINE experiment may allow to discover or rule out the existence of the CP in the Supe…

Hyperon production in Pb+Pb collisions at the CERN-SPS

New results on the production of Xi and Omega hyperons in Pb+Pb interactions at 40AGeV and Lambda at 30AGeV are presented. Transverse mass spectra as well as rapidity spectra of these hyperons are shown and compared to previously measured data at different beam energies. The energy dependence of hyperon production (4pi yields) is discussed. Additionally, the centrality dependence of Xi^{-} production at 40AGeV is presented.

Open Charm measurements at the NA61 experiment at CERN SPS

The strong interactions programme of the NA61/SHINE experiment at CERN SPS has been extended through the use of new silicon Vertex Detector which provides precise measurements of exotic particles with short lifetime. The detector was designed to meet the challenges of primary and secondary vertexes reconstruction at high spatial resolution. An initial version of the Vertex Detector called SAVD (Small Acceptance Vertex Detector) was installed last end of 2016, and data was from Pb+Pb collisions was collected in 2016, for Xe+La in 2017, as well as further Pb+Pb collisions this year. First indica…

Energy Dependence of Particle Production in nucleus-nucleus collisions at the CERN SPS

New preliminary results on kaon and pion production in central 30AGeV Pb+Pb collisions are presented. The data are compared to data at lower and higher energies to examine the energy dependence of the kaon to pion ratios and the inverse slope parameters of kaons. The results are compared to expectations from models with and without a phase transition to the Quark Gluon Plasma.

Energy and rapidity dependence of electric charge correlations at 20-158GeV beam energies at the CERN SPS (NA49)

Electric charge correlations are studied with the Balance Function method for central Pb + Pb collisions at the CERN - SPS. The results on centrality selected Pb + Pb interactions at 40 and 158 AGeV are presented for the first time for two different rapidity intervals. In the mid-rapidity region a decrease of the width with increasing centrality of the collision is observed whereas in the forward rapidity region this effect vanishes. This could suggest a delayed hadronization scenario. In addition, the results from a first attempt to study the energy dependence of the Balance Function througho…

NA49 Energy Scan Results for Central Lead-Lead Collisions at the CERN SPS

The energy dependence of hadron production in central Pb-Pb collisions at SPS energies is presented and compared with data at lower and higher energies and with results from p-p interactions. It is observed that there is little change in transverse activity in the SPS energy range, that there is a steepening rate of increase of pion production and that the K+/pi+ ratio exhibits a sharp peak located at about 30 AGeV. The Lambda/pi ratio also shows a pronounced maximum which is weaker in Ksi/pi and absent in Omega/pi.