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The Current status of the MPD@NICA Project at JINR. A.Litvinenko for MPD@NICA collaboration litvin@moonhe.jinr.ru. MPD@NICA Project. The M ulti P urpose D etector( MPD ) is designed to study Heavy I on collisions at the N uclotron-based heavy I on
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TheCurrent status of the MPD@NICA Project at JINR A.Litvinenko for MPD@NICA collaboration litvin@moonhe.jinr.ru A.Litvinenko VBLHEP JINR
MPD@NICA Project The MultiPurposeDetector(MPD)isdesignedtostudy Heavy IoncollisionsattheNuclotron-based heavyIon ColliderfAcility(NICA)atJINR,Dubna. ( A.Litvinenko VBLHEP JINR
Outline • Motivation • Observables • Detector conception • Simulation of some tasks • Conclusions A.Litvinenko VBLHEP JINR
MPD@NICA Project The MultiPurposeDetector(MPD)isdesignedtostudy Heavy IoncollisionsattheNuclotron-based heavyIon ColliderfAcility(NICA)atJINR,Dubna. • Colliding nuclei up to the Au • Energy • Luminosity ( A.Litvinenko VBLHEP JINR
http://nica.jinr.ru/ http://nica.jinr.ru/files/CDR_MPD/MPD_CDR_en.pdf http://nica.jinr.ru/files/WhitePaper.pdf A.Litvinenko VBLHEP JINR
SYNCHROPHASOTRON NUCLOTRON Fix. Targ. Experiments NICA MPD A.Litvinenko VBLHEP JINR
MPD general view A.Litvinenko VBLHEP JINR
Some history PHENIX Energy STAR NA-61 NA-49 NICA CBM Time A.Litvinenko VBLHEP JINR
Why the initial energy Parameter of Fireball (Parameters of exited hadronic matter) Baryon density Energy density (Bjorken equation) Energy density increases with increasing initial energy Baryon density decreases with increasing initial energy A.Litvinenko VBLHEP JINR
Energy density density of charged hadrons PHOBOS DATA A.Litvinenko VBLHEP JINR
Baryon charge of fireball can be obtained from net-proton distribution Net protons = By the way, is often used Stopping power and 11 A.Litvinenko VBLHEP JINR
RHIC Energy Small baryon density Lattice QCD F. Karsch, Lecture Notes in Physics 583 (2002) 209. A.Litvinenko VBLHEP JINR
Rough estimation – ideal mass less gas Bosons -- 1- degree of freedom: Fermions -- 1- degree of freedom: 2 quarks 3 quarks A.Litvinenko VBLHEP JINR
For 14 A.Litvinenko VBLHEP JINR
Creation of the deconfirment QGP state in heavy-ion collisions, Kind of transition depends on the net baryon density high baryon density first order transition to QGP A.Litvinenko VBLHEP JINR
The horn in strangeness yield NA-49 data A.Litvinenko VBLHEP JINR
Conclusions I • There is experimental indication on singularity at NICA energy • The initial energy scan is necessary for determination of EoS parameters • It is interesting to know where is critical point • The first order transition can give many interesting signals including signals from mixed phase. A.Litvinenko VBLHEP JINR
Nuclei collisions complicated process. To study it we need a lot of observables. A.Litvinenko VBLHEP JINR
Space-time structure of heavy ions collisions kineticfreeze-out (no collisions) Chemical freeze-out (no particles production) Parton-parton interaction Initial inelastic collisions world line 19
Observables Particles ratios temperature and chemical potential at Chemical Freezeout A.Litvinenko VBLHEP JINR
Observables Particle spectra temperature and expansion velosity at Kinematic Freezeout A.Litvinenko VBLHEP JINR
elliptic flow Observables Flows equilibrium time, EoS …. Space eccentricity Elliptic flow Coordinate space asymmetry momentum space anisotropy A.Litvinenko VBLHEP JINR
Observables Fluctuations:Multiplicities, Particle Ratios, mean pT … Fluctuations from 1st order transition have to be more strong No hard collisions at small energy A.Litvinenko VBLHEP JINR
General view of the MPD CD-central parts,(FS-A, FS-B) - two forward spectrometers (optional). Superconductor solenoid (SC Coil) and magnet yoke, inner detector (IT), straw-tube tracker (ECT),time-projection chamber (TPC),time-of-flight stop counters (TOF), electromagnetic calorimeter(ECal), fast forward detectors (FFD), beam-beam counter (BBC), and zero degree calorimeter(ZDC). A.Litvinenko VBLHEP JINR
Central Detector of MPD with based dimensions A.Litvinenko VBLHEP JINR
MPD pseudorapidity coverage. The barrel part The endcaps (FS-A and FS-B) A.Litvinenko VBLHEP JINR
Magnet of MPD Distribution of the magnetic induction The field inhomogeneityin the tracker area of the detector is about 0.1%. A.Litvinenko VBLHEP JINR
Detector simulation software packages The software framework for the MPD experiment (MpdRoot) is based on the objectorientedframework FairRoot and provides a powerful tool for detector performancestudies, development of algorithms for reconstruction and physics analysis of the data. http://mpd.jinr.ru A.Litvinenko VBLHEP JINR
Time projection chamber (TPC) (tracking, PID) Schematic view A.Litvinenko VBLHEP JINR
Time projection chamber (TPC) Simulation view of TPC in the MpdRoot. A.Litvinenko VBLHEP JINR
Time projection chamber (TPC) Tracks reconstruction Charge particle tracks in the TPC volume for a central Au + Au collision UrQMD 2.3 A.Litvinenko VBLHEP JINR
Time projection chamber (TPC) Particle identification Separation of particles in the TPC by ionization loss A.Litvinenko VBLHEP JINR
Inner Tracker System (vertex reconstruction, secondary vertex reconstruction) A.Litvinenko VBLHEP JINR
Inner Tracker System Hyperons identification TPC TPC + ITS A.Litvinenko VBLHEP JINR
Time of Flight System (ToF) Multigap Resistive Plate Counters (MRPC) PID (0.1–2 GeV/c) – ToF + TPC Barrel of TOF system Distribution of RPC elements in the barrel A.Litvinenko VBLHEP JINR
Time of Flight System (ToF) PIDwith TOF and TPC A.Litvinenko VBLHEP JINR
Electromagnetic calorimeter The “shashlyk” type calorimeter sampling Pb(0.5mm) + Sc(1.5 mm) (170 layers) the “shashlyk” calorimeter module Detector sector ECAL detector. A.Litvinenko VBLHEP JINR
Electromagnetic probes provide information about: • Early stage of collision • Temperatureevolution of the system from its formation to thermal freez-out • Comparison of resonanses properties as seen in dielectron and hadronicdecay channels in Au+Au collisions A.Litvinenko VBLHEP JINR
A.Litvinenko VBLHEP JINR
A.Litvinenko VBLHEP JINR
The importance of the centrality classification Elliptic flow Space eccentricity Nuclear Physics A V757, No. 1-2 , p.184,2005 elliptic flow scaling with space eccentricity short equlibration time A.Litvinenko VBLHEP JINR
LAQGSM, Sqrt(S)=5 GeV URQMD, Sqrt(S)=5 GeV Total kinetic energy of all nucleonsand fragments directed to ZDC A.Litvinenko VBLHEP JINR
The centrality determination: ZDC + number tracks in TPC A.Litvinenko VBLHEP JINR
Position of extZDC within MPD set-up extZDC Reaction plane peconstruction
Methods of reaction plane reconstruction • Using 1-st Fourier harmonics → directed flow in a collision in Lab frame: Method 1: b φR Method 2: → Optimize weight wi to increase sensitivity to RP → combine measurements for η<0 and η>0 to improve precision, study as a function of impact parameter b Reaction plane peconstruction
Directed Flow v1 vs Rapidity y nucleons π-mesons UrQMD QGSM Reaction plane peconstruction
Extended ZDC detector dcell = 5x5 cm, 420 cells in each side of MPD • Simulation of extended ZDC within mpdroot: • L = 120 (60, 40) cm • 5 < R < 61 cm, z0=270 cm, 1<θ<12.5o (2.2<η<4.8) • dcell = 5x5,10x10 cm • wi=ΣEvis in active layers of 1 module → use methods 1 and 2 for RP reconstruction • No π vs p/ion identification • Geant 4 , QGSP_BIC physics model dcell = 10x10 cm, 121 cells in each side of MPD Reaction plane peconstruction
Resolution δφRP and <cos δφRP> vs b Effects of ZDC cell size and length, beam energy and interaction model Reaction plane reconstruction
Polarization observables at MPD. one example Analyzing powers Ayy of the reactions: + = S wave D wave A.Litvinenko VBLHEP JINR
Experimental data C.E.Allgower et al., Phys.Rev. D 65 ,092008, (2002) Simulation for MPD A.Litvinenko VBLHEP JINR