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https://www.sciencedirect.com/science/article/pii/S0370269317305646
DOI: 10.1016/j.physletb.2017.07.017
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©2017
by Elsevier. All rights reserved.
DIRETORIA DE TRATAMENTO DA INFORMAÇÃO
Cidade Universitária Zeferino Vaz Barão Geraldo
CEP 13083-970 – Campinas SP
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http://www.repositorio.unicamp.br
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Physics
Letters
B
www.elsevier.com/locate/physletb
Centrality
dependence
of
the
pseudorapidity
density
distribution
for
charged
particles
in
Pb–Pb
collisions
at
√
sNN
=
5
.
02 TeV
.
ALICE
Collaboration
a
r
t
i
c
l
e
i
n
f
o
a
b
s
t
r
a
c
t
Articlehistory: Received9January2017
Receivedinrevisedform19June2017 Accepted9July2017
Availableonline14July2017 Editor:L.Rolandi
We present the charged-particle pseudorapidity density in Pb–Pb collisions at √sNN=5.02 TeV in
centralityclassesmeasuredbyALICE.Themeasurementcoversawidepseudorapidityrangefrom−3.5 to5,whichissufficientforreliableestimatesofthetotalnumberofchargedparticlesproducedinthe collisions.Forthemostcentral(0–5%)collisionswefind21400±1300,whileforthemostperipheral (80–90%)we find230±38.Thiscorresponds toan increaseof(27±4)% over theresults at√sNN=
2.76 TeV previouslyreportedbyALICE.Theenergydependenceofthetotalnumberofchargedparticles produced inheavy-ioncollisions is foundtoobey amodifiedpower-lawlikebehaviour. The charged-particlepseudorapiditydensityofthemostcentralcollisionsiscomparedtomodelcalculations—none ofwhichfullydescribes themeasureddistribution.Wealsopresentanestimateoftherapiditydensity ofchargedparticles.Thewidth ofthatdistributionisfoundtoexhibitaremarkableproportionalityto thebeamrapidity,independentofthecollisionenergyfromthetopSPStoLHCenergies.
©2017TheAuthor(s).PublishedbyElsevierB.V.ThisisanopenaccessarticleundertheCCBYlicense (http://creativecommons.org/licenses/by/4.0/).FundedbySCOAP3.
1. Introduction
Inultra-relativisticheavy-ioncollisions a denseandhot phase of nuclear matter is created [1–4]. This phase of QCD matter is consideredtobe aplasmaofstronglyinteractingquarksand glu-ons and is therefore labelled the sQGP [5]. The multiplicity of primary, charged particles produced in heavy-ion collisions is a keyobservabletocharacterisethepropertiesofthemattercreated inthese collisions [6]. The studyof theprimary charged-particle pseudorapiditydensity(dNch
/
dη
) overa wide pseudorapidity(η
) rangeanditsdependenceoncollidingsystem,centre-of-mass en-ergy,andcollision geometryisimportantto understandthe rela-tivecontributionstoparticleproductionfromhardscatteringsand softprocesses,andmayprovideinsightintothepartonicstructure oftheinteractingnuclei.Wehave previouslyreportedmeasurements on primary charged-particlepseudorapiditydensitiesoverawidepseudorapidityrange inPb–Pbcollisions atthecentre-of-mass energypernucleonpair
√
sNN
=
2.
76 TeV[7].InthisLetter,westudythesedistributionsinthepseudorapidityintervalfrom
−
3.
5 to5 atacollisionenergyof√
sNN
=
5.
02 TeV asa functionofthe centrality.Pseudorapidityisdefinedas
η
≡ −
log(
tan(ϑ/
2))
,whereϑ
istheanglebetweenthe charged-particle trajectory andthebeam axis(z-axis).Nuclei are extendedobjects,andtheircollisionscanbecharacterisedby cen-trality— the experimental proxy forthe un-measurable distanceE-mailaddress:alice-publications@cern.ch.
between the centres of the colliding nuclei (impact parameter). A primary particle is a particle with a mean proper lifetime
τ
larger than 1 cm
/
c, which is either a) produced directly in the interaction, or b) from decays of particles withτ
smaller than 1 cm/
c,restrictedtodecaychainsleadingtotheinteraction[8].In this Letter, all quantities reported are forprimary charged parti-cles,thoughwewillomit“primary”forbrevity.Withthe largepseudorapidity coverage available inALICE, we can reliably estimate, for all centrality classes, the total number ofchargedparticles produced inthecollisions. We thereforealso presentthefirstmeasurement ofthetotalcharged-particle multi-plicityinPb–Pbcollisions at
√
sNN=
5.
02 TeV asafunctionofthenumberofnucleonsparticipatinginthecollisions(Npart).
Finally, we transform the measured dNch
/
dη
distribution for the5%mostcentralcollisionsintocharged-particlerapiditydensity (dNch/
d y),andweexaminethecentre-of-massenergydependence of the width of that distribution. The rapidity ( y) of a particle withenergyE andmomentumcomponentpzalongthebeamaxis isdefinedas y≡
12log(
[
E+
pz]/[
E−
pz])
.Thecomparisonofthe width of the dNch/
d y at different collision energies provides an insight intotheconstraints onthe overall productionmechanism ofchargedparticles.2. Experimentalsetup
A detailed description of ALICE and its performance can be found elsewhere [9,10]. In the following, we briefly describe the detectorsrelevanttothisanalysis.
http://dx.doi.org/10.1016/j.physletb.2017.07.017
0370-2693/©2017TheAuthor(s).PublishedbyElsevierB.V.ThisisanopenaccessarticleundertheCCBYlicense(http://creativecommons.org/licenses/by/4.0/).Fundedby SCOAP3.
TheSiliconPixelDetector(SPD),theinnermostpartoftheInner TrackingSystem(ITS), consistsoftwo cylindricallayers ofhybrid siliconpixelassembliescovering
|
η
|
<
2 and|
η
|
<
1.
4 fortheinner andouterlayers,respectively.Combinationsofhitsoneachofthe twolayers consistent withtracksoriginatingfromtheinteraction pointformtracklets.TheForwardMultiplicityDetector(FMD)isasiliconstrip detec-torwhich,recordstheenergydepositedbyparticlestraversingthe it.Thedetectorcoversthepseudorapidityregions
−
3.
5<
η
<
−
1.
8 and1.
8<
η
<
5,andhasalmostfullcoverageinazimuth(ϕ
),and highgranularityintheradial(η
)direction.The third detector system used in this analysis is the V0. It consistsoftwosub-detectors:V0-AandV0-C coveringthe pseudo-rapidity regions 2
.
8<
η
<
5.
1 and−
3.
7<
η
<
−
1.
7,respectively, eachmadeup ofscintillatortileswithatiming resolution<
1 ns. The fast signals from eitherof V0-A or V0-C are combined in a programmable logic to form a trigger signal and to reject back-groundevents.Furthermore,the combined pulseheight signal of bothsub-detectors formsthebasis fortheclassificationofevents intodifferentcentralityclasses[11].The Zero-Degree Calorimeter (ZDC) measures the energy of spectator (non-interacting) nucleons with two components: one measures protons and the other measures neutrons. The ZDC is locatedatabout112.5 mfromtheinteractionpointonbothsides ofthe experiment [9]. The ZDCalsoprovides timing information usedtoselectcollisionsintheoff-linedataprocessing.
3. Datasampleandanalysismethod
Theresults presentedherearebasedon datacollected by AL-ICEin2015during thePb–Pbcollision runofthe LHCat
√
sNN=
5
.
02 TeV. About 100000 eventswitha minimumbias trigger re-quirement[12] were analysed inthe centralityrange from0% to 90%.TheminimumbiastriggerforPb–PbcollisionsinALICE,which definesthe so-called visiblecross-section, is definedas a coinci-dencebetweentheA(z>
0)andC(z<
0)sidesoftheV0detector. Thestandard ALICEeventselection[13] andcentrality estima-torbasedontheV0–amplitude[11]areusedinthisanalysis.The eventselection consistsof: exclusionof backgroundevents using the timing information fromthe ZDC andV0 detectors; verifica-tionofthetriggerconditions;andareconstructed positionofthe collision.Asdiscussedelsewhere[11],the90–100%centralityclass hassubstantialcontributionsfromQEDprocessesandistherefore notincludedintheresultspresentedhere.The measurement ofthe charged-particle pseudorapidity den-sityat mid-rapidity (
|
η
|
<
2) is obtainedfroma tracklet analysis usingthetwolayersoftheSPD.Theanalysismethodusedis iden-ticaltowhat haspreviously beenpresented [12,14,15]. Notethat noattemptismadetocorrectforknowndeficiencies,suchas devi-ationsinthenumberofstrangeparticlesortransversemomentum (pT)distributionscomparedtoexperimentalmeasurements[11,16, 17], in the eventgenerators used to obtain the corrections from simulations (e.g.,HIJING). It isfound, through simulationstudies, thattrackletreconstructionfirstandforemostdependsonthelocal hit density andonly weakly on particle mix andtransverse mo-mentum.Forexample,thedeficitofstrangeparticlesintheevent generatoreffectstheresultbylessthan2%.Sincetheevent genera-torsgenerally,afterdetectorsimulation,producealocalhitdensity thatisconsistentwithwhatisobservedindata,weobservea cor-respondencebetweenthetrackletsamplesofbothsimulationsand data.Ontheother hand,changingthenumberoftracklets corre-spondingtostrangeparticlesapostioritomatchthemeasured rel-ativeyieldsdramaticallybiasesthesimulatedtrackletsampleaway fromthemeasured,thusentailingsystematicuncertaintiesthatare beyondtheeffect oftheknown eventgeneratordeficiencies, andFig. 1. [Colour online.] Charged-particlepseudorapidity density forten centrality classesoverabroadηrangeinPb–Pbcollisionsat√sNN=5.02 TeV.Boxesaround the pointsreflectthe totaluncorrelated systematicuncertainties,whilethe filled squares on the right reflect the correlated systematicuncertainty (evaluated at η=0).Statisticalerrorsaregenerallyinsignificantandsmallerthanthemarkers. Alsoshownisthereflectionofthe3.5<η<5 valuesaroundη=0 (opencircles). Thelinecorrespondstofitsofthedifference betweentwoGaussianscentredat η=0 ( fGG)[7]tothedata.
assuchdonotimprovetheaccuracyofthemeasurements.Instead, variationsontheeventgeneratorsareusedtoestimatethe system-aticuncertaintiesasdetailedelsewhere[12,14,15].
Intheforwardregions (
−
3.
5<
η
<
−
1.
8 and 1.
8<
η
<
5),the measurement isprovidedby theanalysisofthedepositedenergy signal intheFMD.The analysismethodusedisidenticaltowhat haspreviouslybeenpresented[7,14]:a statisticalapproachto cal-culatetheinclusivenumberofchargedparticles;andadata-driven correction — derived from previous satellite-main collisions — to removethelargebackgroundfromsecondaryparticles.4. Systematicuncertainties
For the measurements at mid-rapidity the sources and de-pendencies ofthesystematicuncertaintiesare detailedelsewhere [7,12,15]. The magnitude of the systematic uncertainties is un-changed withrespecttoprevious results,andamounts to2
.
6% atη
=
0 and 2.
9% atη
=
2,mostofwhichiscorrelatedover|
η
|
<
2, andlargelyindependentofcentrality.Thesystematicuncertaintyontheforwardanalysisisevaluated usingthesametechnique asforpreviousresults[7].Wefindthat theuncertaintyisuncorrelatedacross
η
anthatitamountsto6.
9% forη
>
3.
5 and6.
4% elsewherewithintheforwardregions.The systematic uncertainty on dNch
/
dη
due to the centrality classdefinitionisestimatedas0.
6% forthemostcentraland9.
5% for the most peripheral class [15]. The uncertainty is estimated by usingalternative centrality definitions basedon SPD hit mul-tiplicitiesandbyvaryingthefractionofthevisiblehadronic cross-section. The 80–90% centrality class has some residual contam-ination from electromagnetic processes detailed elsewhere [11], which givesrisetoa 4% additionalsystematicuncertainty onthe measurements.In summary,thetotal systematicuncertaintyvariesfrom2
.
6% atmid-rapidityinthemostcentralcollisionsto12.
4% atthevery forwardrapiditiesforthemostperipheralcollisions.5. Results
Fig. 1 presents the charged-particle pseudorapidity densityas a function of pseudorapidity for ten centralityclasses. The mea-surements from the SPD and FMD are combined in regions of overlap (1
.
8<
|
η
|
<
2) between the two detectors by taking the weighted average using the non-shared uncertainties as weights. Finally,basedonthe symmetryofthecollisionsystem, theresult issymmetrisedaroundη
=
0,andextendedintothenon-measuredFig. 2. [Colouronline.]Totalnumberofchargedparticlesasafunctionofthemean numberofparticipating nucleons [11]. The totalcharged-particle multiplicity is givenastheintegraloverdNch/dηoverthemeasuredregion(−3.5<η<5)and
extrapolationsfromfittedfunctionsintheunmeasuredregions.Thecontribution fromunmeasured ηregions amounts to≈30% ofthe totalnumberofcharged particles.Theuncertaintyontheextrapolationtotheunmeasuredpseudorapidity regionissmallerthanthesizeofthemarkers.Thecontributiontothesystematic uncertaintiesfromthecentralitydeterminationandelectromagneticprocessesare vanishingcomparedtothecontributionfromthelargestdifferencesbetweenthe fittedfunctions.Afunctioninspiredbyfactorisation[18]isfittedtothedata,and thebestfityieldsa=51.5±7.3,b=0.16±0.05.
region
−
5<
η
<
−
3.
5 byreflectingthe3.
5<
η
<
5 valuesaroundη
=
0. Complementing resultpreviously reported atmid-rapidity [15],wefind dNch/
dη
|
|η|<0.5=
17.
52±
0.
05(
stat)
±
1.
84(
sys)
and Npart=
7.
3±
0.
1 inthe80–90%centralityclass.Themeasured distributions arefittedwithfourfunctions fGG, fP, fT,and fB [7],whichare the differenceof twoGaussian dis-tributions centredat
η
=
0; aparametrisation proposed by PHO-BOS[18];atrapezoidalform;andaplateauconnectedtoGaussian tails, respectively. To extract the total number of charged parti-cles,wecalculatetheintegralanduncertaintyfromthedatainthe measured region and use the integrals of the fitted functionsin theunmeasuredregions uptothe beamrapidity±
ybeam= ±
8.
6. Asforthepreviousmeasurementsat√
sNN=
5.
02 TeV,thecentralvalue inthe unmeasuredregions (
−
8.
6<
η
<
−
3.
5 and 5<
η
<
8.
6)istakenfromthefitofthefunction fT,whiletheuncertainty isevaluatedasthelargestdifferencebetweenthe fittedfunctions scaled by 1/
√
3 [7,14]. The total charged-particle multiplicity is shownin Fig. 2versus the meannumber of participating nucle-ons (Npart) estimated from a Glauber calculation [11,15]. After removing correlated systematic uncertainties, we observe an in-creaseinthe totalnumberofchargedparticles of(
27±
4)
% with respectto the measurements at√
sNN=
2.
76 TeV[7] forallcen-trality classes. The line shown in Fig. 2 corresponds to a fit of a function inspired by factorisation [18]. The function illustrates scalingby numberofparticipantpairs,witha smallperturbation proportional to the cubic rootof the number of participants. As the number of nucleon–nucleon collisions (Ncoll) scales roughly likethesquareofthenumberofparticipantsNcoll
≈
N2part[19],we seenoindication of scalingby numberofnucleon–nucleon colli-sions.The observed total Nch dependenceon Npartprovides no evidenceofanysignificantincreaseinthenumberofhard scatter-ingsbetweentheparticipatingnucleonsandpartons.InFig. 3,wecomparethecharged-particle pseudorapidity den-sity for the 0–5% most central collisions to three models: HI-JING [20]; EPOS–LHC [21]; and KLN [22,23], also for the 0–5% mostcentral,exceptforKLNwhichisshownforthe0–6% central-ityclass.TwoversionsofHIJINGareused:version 1.383,withjet quenchingdisabled,shadowing enabled, anda hard pT cut-offof
2.3 GeV;andthenewerversion 2.1[24].Botharetwo-component models witha softand hard sector definedby a pT cut-off
sep-arating the two. In the 2.1 implementation, HIJING uses an up-graded parametrisation of the nuclear parton distribution
func-Fig. 3. [Colouronline.]ComparisonofdNch/dη inthe0–5%(0–6%forKLN)most
centralcollisionsoftwoversionsofHIJING,KLN,andEPOS–LHCmodelcalculations tothemeasureddistribution.
Fig. 4. [Colouronline.]Totalnumberofchargedparticlesasafunctionof√sNNfor themostcentralcollisionsatAGS (0–5%Au–Au)[25,26],SPS (0–5%Pb–Pb)[27,28], RHIC (0–5%and0–6%Au–Au)[18,29,30],andLHC (0–5%Pb–Pb)[14].Thedotted, dashed,andfulllinesareextrapolationsfromfitstolowerenergyresults[14],while thedash-dottedlineisafitoverallenergies,including√sNN=5.02 TeV.
tions.Thisresultsinalargercrosssectionforsoftprocessesanda smallercrosssectionforjetproduction.TheKLN modelisbasedon Colour-Glass-Condensate initial conditions, while EPOS-LHC uses so-called parton-ladders which hadronise in a medium. While noneofthethreemodels describethemeasured charged-particle pseudorapiditydensityoverthefull pseudorapidityrange,we ob-serve some differences: HIJING 1.383 over-predicts the charged-particle production especially away from
η
≈
0; EPOS–LHC and HIJING 2.1 consistently under-predict the charge-particle produc-tion; whereas KLN, EPOS–LHC, and HIJING 2.1 give a shape rea-sonably close to the observed distribution. Not shown in Fig. 3, forbothHIJING 1.383andEPOS–LHC,theseobservationsholdover allcentralityclassesi.e.,HIJING 1.383consistentlyproducesfartoo manyparticlesawayfrommid-rapidityandEPOS–LHCconsistently under-predicts the charged-particle yield over the fullη
range. Thesetrends becomeincreasingly morepronouncedformore pe-ripheralcollisions.Fig. 4 showsthe total number of charged particles produced in themostcentral heavy-ion collisions asa functionof the col-lisionenergy,ranging from
√
sNN=
2.
6 GeV to 5.
02 TeV [14].Thedotted,dashed,andfull-drawnlinesinthefigurerepresent extrap-olationsfromlowerenergyresultstothecurrenttopLHCenergyof
√
sNN
=
5.
02 TeV.Noneofthesepredictionsfullydescribethedata.A refitofthesimplemodelofalogarithmic-dampenedpower-law inthesquarecollisionenergy(s)includingfromthelowesttothe highestenergyresults,shownasthedash-dottedline, does accu-ratelydescribethetotalnumberofchargedparticlesatallavailable energies.
Fig. 5. [Colour online.] Estimate ofdNch/d y in the most central (0–5%)Pb–Pb
collisionsat √sNN=5.02 TeV. Alsoshown arethe Landau–Wong [31], Landau– Carruthers[32],Gaussian,anddouble-Gaussiandistributions.
Fig. 6. [Colouronline.]Scalingbehaviourasafunction√sNN ofthewidthofthe charged-particleor-pionrapidity-densitydistributionwithrespecttotheLandau– Carrutherswidth(top)andrapidityrange(bottom).Charged-pionpointsfromAGS andSPSareadaptedfromtheliterature[33],whilethePHOBOS(filledcrosses)[34] andBRAHMS(opencrosses)[30]charged-hadronpointsaretranslatedfromthe cor-respondingdNch/dηresults.
We can calculate the Jacobian transform from
η
to rapidityy by assuming the same transverse momentum distribution of (anti-)protons, and charged kaons andpions, andthe same par-ticleratios inPb–Pb collisions at
√
sNN=
5.
02 TeV as in√
sNN=
2
.
76 TeV.TheresultispresentedinFig. 5forthe0–5%most cen-tral collisions. The effect on the Jacobian fromthe changeof pTspectraandparticleratioswhenincreasingthecollisionenergyby almosta factortwoisevaluated usingtheEPOS–LHC model[21]. Itisfound,thattheeffectisatmost3‰onbothdNch
/
d y and y — muchsmallerthanthesystematicuncertaintyandη
resolutionof theanalysis.Fig. 5alsoshowstheexpectedcharged-particle rapid-itydensities from the Landau–Carruthers [32] andLandau–Wong [31] models,both assuming Landauhydrodynamics i.e., basedon areactionscenariowithfullstoppingofthereactionpartnersand asubsequentthermodynamic evolution.Themeasurements, how-ever,areseentobeconsistentwithaGaussiandistributionwitha widthof4.
12±
0.
10,much widerthan thewidth expectedfrom thetwomodels.Abestparameterfitofthesumoftwo Gaussian distributionswithmeanssymmetricaroundy=
0,is indistinguish-ablefromthesingleGaussiancase.In the top part of Fig. 6 we compare the widths of the charged-particle or -pion rapidity density distribution extracted frommeasurements tothe expectedwidth
σ
2L-C
=
log(
√
sNN
/
2mp)
from Landau–Carruthers, where mp is the proton mass, at colli-sion energies ranging from2
.
6 GeV up to 5.
02 TeV. An increase of≈
7% ofσ
dNX/d y/
σ
L-C is seen from the√
sNN
=
2.
76 TeVAL-ICE measurements [14]. The full evolution is consistent with an almost linearriseasa function oflog
√
sNN fromthe topSPSen-ergyat
√
sNN=
17.
3 GeV. Itcanbe shown[35] thatthe widthofthe rapidity-density distribution in Landau hydrodynamics scales as
σ
dNX/d y∝
1/(
1−
c2
s
)
,wherecsisthespeedofsoundinthemat-ter.The lifetimeofthe systemscales inverselywithcs,andgiven that the measured widthis larger than the predicted by Landau hydrodynamics, it is an indication that, given the considerations above,thelifetimeisshorterthansuggested.
In the bottom part of Fig. 6 we compare the width of the dNch
/
d y distributiontotheavailable rapidityrange(2 ybeam). We observe no dependence ofthis ratio from√
sNN=
17.
3 GeV andupward, indicating that the available phase–space constrains the width of that distribution. The charged-hadron measurements at RHIC (crosses) from the BRAHMS [30] and PHOBOS [34] mea-surements ofdNch
/
dη
areconverted to dNch/
d y usingthe same method as applied to the ALICE data. Previously, charged-pion measurements fromBRAHMShavebeenreported[33].Thesedata arenotincludedbecauseare-evaluationusingRHICRun-4Au–Au datahasnotbeenfinalised[36].Fromtheobservedsp scalingofthecharged-particle pseudora-pidity densityatmid-rapidity[15] weexpect a20% increaseover
√
sNN
=
2.
76 TeV in thelevelof dNch/
dη
|
|η|<0.5 andfromthe ex-tractedwidthofdNch/
d y weobserveanadditional7%,consistent withtheincreaseof27% over√
sNN=
2.
76 TeV inthetotalnumberofchargedparticlesproducedin
√
sNN=
5.
02 TeV collisions.6. Conclusions
Thecharged-particlepseudorapiditydensityismeasuredinPb– Pb collisions at
√
sNN=
5.
02 TeV over the psuedorapidity range−
3.
5<
η
<
5. The totalnumber ofchargedparticles produced is determined owing to the large pseudorapidity acceptance of AL-ICE.Thelatterincreasesbytwoordersofmagnitudefromthemost peripheralto themostcentralcollisions andscales approximately with the number of participating nucleons. The increase in the totalnumberofchargedparticlesrelativeto√
sNN=
2.
76 TeV ises-timated tobe
(
27±
4)
%. Thecharged-particle rapidity densityfor themostcentralcollisions isextracted, andthewidthofthat dis-tribution is compared to predictionsfrom theLandau–Carruthers andLandau–Wonghydrodynamicmodels.Itisfoundthatthe mea-suredcharged-particlerapiditydensitybecomesincreasinglywider as a function of collision energy than predicted by Landau hy-drodynamics. The width of the charged-particle rapidity density is seen to scale with the beam rapidity, which implies that the available phase space determines the longitudinal extend of the charged-particle production.Thephase spacedominancestarts at thetopSPSenergyandpersistfortwo ordersofmagnitudeupto thetopLHCenergy.Acknowledgements
The ALICECollaboration would like to thank all its engineers andtechniciansfortheirinvaluablecontributionstothe construc-tion of the experiment and the CERN accelerator teams for the outstanding performance of the LHC complex. The ALICE Collab-oration gratefully acknowledges the resources and support pro-videdbyallGridcentresandtheWorldwideLHCComputingGrid (WLCG) collaboration. The ALICE Collaboration acknowledges the following fundingagenciesfortheir supportin buildingand run-ningthe ALICEdetector:A.I. AlikhanyanNationalScience Labora-tory(YerevanPhysicsInstitute)Foundation (ANSL),State Commit-teeofScienceandWorldFederationofScientists(WFS),Armenia; Austrian Academyof SciencesandNationalstiftung fürForschung, Technologie und Entwicklung, Austria; Conselho Nacionalde De-senvolvimento Científico e Tecnológico (CNPq), Universidade Fed-eral do Rio Grande do Sul (UFRGS), Financiadora de Estudos e Projetos (Finep) and Fundação de Amparo à Pesquisa do Estado
deSãoPaulo(FAPESP),Brazil;MinistryofScience&Technologyof China(MSTC),NationalNaturalScienceFoundationofChina(NSFC) andMinistryofEducationofChina(MOEC),China;Ministryof Sci-ence,EducationandSportandCroatianScienceFoundation, Croa-tia;MinistryofEducation,YouthandSportsoftheCzechRepublic, Czech Republic; The Danish Council for Independent Research– NaturalSciences,theCarlsbergFoundationandDanishNational Re-search Foundation (DNRF), Denmark;Helsinki Institute ofPhysics (HIP),Finland;Commissariatàl’EnergieAtomique(CEA)and Insti-tut Nationalde Physique Nucléaire etde Physique des Particules (IN2P3)andCentre National de laRecherche Scientifique (CNRS), France; Bundesministerium für Bildung, Wissenschaft, Forschung undTechnologie(BMBF)and GSI Helmholtzzentrumfür Schweri-onenforschung GmbH, Germany; Ministry of Education, Research andReligiousAffairs,Greece;NationalResearch,Developmentand Innovation Office, Hungary; Department of Atomic Energy, Gov-ernment of India (DAE) and Council of Scientific and Industrial Research (CSIR), New Delhi, India; Indonesian Institute of Sci-ence,Indonesia;CentroFermi- Museo StoricodellaFisica e Cen-troStudi e Ricerche EnricoFermi andIstitutoNazionale di Fisica Nucleare(INFN), Italy; Institute forInnovative Science and Tech-nology, Nagasaki Institute of Applied Science (IIST), Japan Soci-ety for the Promotion of Science (JSPS) KAKENHI and Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan;Consejo Nacional de Ciencia y Tecnología (CONA-CYT), through Fondo de Cooperación Internacional en Ciencia y Tecnología(FONCICYT)andDirecciónGeneralde Asuntosdel Per-sonal Academico (DGAPA), Mexico; Nationaal instituut voor sub-atomaire fysica (Nikhef), Netherlands; The Research Council of Norway,Norway;CommissiononScienceandTechnologyfor Sus-tainableDevelopmentintheSouth(COMSATS),Pakistan;Pontificia UniversidadCatólicadelPerú,Peru;MinistryofScienceandHigher EducationandNationalScience Centre,Poland;Korea Institute of ScienceandTechnology Information andNationalResearch Foun-dation of Korea (NRF), Republic of Korea; Ministry of Education andScientific Research,InstituteofAtomic PhysicsandRomanian National Agency for Science, Technology and Innovation, Roma-nia;JointInstituteforNuclearResearch(JINR),Ministryof Educa-tionandScienceoftheRussian FederationandNationalResearch CentreKurchatovInstitute, Russia;MinistryofEducation,Science, ResearchandSportoftheSlovak Republic, Slovakia; National Re-search Foundation of South Africa, South Africa; Centrode Apli-cacionesTecnológicasyDesarrolloNuclear(CEADEN),Cubaenergía, Cuba, Ministerio de Ciencia e Innovacion and Centro de Investi-gacionesEnergéticas, Medioambientales y Tecnológicas (CIEMAT), Spain;SwedishResearchCouncil(VR)andKnut&AliceWallenberg Foundation(KAW),Sweden;EuropeanOrganizationforNuclear Re-search,Switzerland;NationalScienceandTechnologyDevelopment Agency(NSDTA),SuranareeUniversityofTechnology(SUT)and Of-fice of the Higher Education Commission under NRU project of Thailand,Thailand;TurkishAtomicEnergyAgency(TAEK), Turkey; National Academy of Sciences of Ukraine, Ukraine; Science and TechnologyFacilitiesCouncil(STFC),UnitedKingdom;National Sci-enceFoundationoftheUnitedStatesofAmerica(NSF)andUnited StatesDepartmentofEnergy, Office ofNuclear Physics(DOE NP), UnitedStatesofAmerica.
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ALICECollaboration
