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CBM and FRRC Mikhail Ryzhinskiy, SPbSPU (on behalf of Russian CBM branch) 1st FRRC International Seminar Compressed Baryonic Matter experiment SIS 300 → U92+ 15-35 GeV/nucleon with beam intensities up to 109/s Z/A = 0.5 nuclei up to 45 GeV/nucleon → exploration of the QCD phase diagram with heavy-ion collisions! → investigation of nuclear matter at highest baryon densities but still moderate temperatures in A+A collisions 2 Fundamental Questions of QCD What is the equation-of-state of strongly interacting matter? (core collapse supernovae, neutron stars, early universe) What is the structure of strongly interacting matter as a function of T and ρB ? (hot and dense hadronic medium, deconfined phase, phase transitions ?) What are the in-medium properties of hadrons as a function of T and ρB ? (partial restoration of chiral symmetry ?) compression + heating = QGP ? 3 The Compressed Baryonic Matter Experiment Muon Ring Imaging detection Cherenkov System Detector PNPI IHEP, PNPI ECAL ITEP, IHEP Transition Tracking Radiation Detector Detectors JINR, PNPI Silicon Tracking Station MSU, MEPHI, JINR, IHEP, Khlopov, CKBM Resistive Plate Chambers (TOF) INR, IHEP Dipol magnet JINR 4 List of candidates for FRRC grants from the Russian Institutes • • • • • • • • • • • • • Sergei Belogurov (ITEP) PhD – Design and Integration of the CBM experiment Mikhail Ryzhinskiy (SPbSPU) PhD – Advanced Digitization and Cluster Finding in MUCH Alexander Sadovsky (INR) PhD – Event-by-event Fluctuations at CBM Experiment Andrei Chernogorov (ITEP) – Design Justification of ECAL Olga Denisova (JINR) – Development of New Mathematical Methods for Experimental Data analysis Alexander Dermenev (INR) – Study of Projectile Spectator Detector for Centrality and Reaction Plane Determination Dmitry Golubkov (ITEP) Optimization of CBM ECAL for χc States Production Studies Alexander Klyuev (MEPhI) - Development or Data-driven, De-randomizing Architecture and Building Blocks for the CBM-XYTER ASIC Eugeny Kryshen (PNPI) – MUCH Design and Construction, Software Development Mikhail Prokudin (ITEP) - Development of CBM ECAL Software Georgy Sharkov (ITEP) - Comparison of ω and φ Meson Cross Sections, Measured in Different Decay Modes using CMMROOT Simulations Taras Vasiliev (JINR) - Participation in the R&D of TRD and Development of Software for Selection of Strange Particles in NucleusNucleus Collisions Vladislav Zryuev (JINR) - Research and Development of Fast and High Resolution Gaseous Detectors for CBM 5 Polarization in HI collisions as a new probe of the phase-transition (T.Vasiliev, Dubna group) A number of polarization observables have been proposed as a possible signature of phase transition in heavy ion collisions: • Decreasing of the Λ0 transverse polarization in central collisions • Global hyperon polarization in non-central events The study of the polarization effects at CBM requires good definition of the reaction plane RP and collision centrality b. Kinematical fit using ASME method for STS(Au+Au centr. coll. 25 AGeV, via UrQMD, GEANT3 m.field) improves accuracy of the primary vertex determination spatial approx. 20 microns (P_V0, beta, tan(alpha)) : better than (1%,0.5 mrad, 0.3) 6 Research and development of fast gaseous detectors for TRD CBM (V.Zryuev, LHEP JINR, Dubna) Main requirements for TRD detectors • High granularity • High radiation hardness • Spatial resolution < 300µm • Minimum material budget • High rate capability • Optimal number of electronic channels • high-speed detector (for the inner part of the detector planes) The results obtained with GEM based detector • Spatial resolution is ~ 90 µm for 600µm strip pitch • Good linearity ~ 1% • Amplification factor ~ 2 x10³. The results obtained with THGEM based detector • • • Spatial resolution is ~ 230 μm fot 1 stage THGEM detector We are working on the technology for construction of THGEM patterns (holes and rims) with a high precision. FEE with n-Xyter chip is planning to use for further tests. R&D work show that both GEM and THGEM detectors require a lot of work to improve its reliability and stability to use them in a large system like CBM. 7 The results obtained with MWPC based detector Layout of the detector installation on the beam line SYS-18 GSI We have performed a systematic study of several types of gas MWPC detectors at high intensity beams at GSI . The R&D of the MWPC detectors shows practically no degradation of the signal amplitudes up to the rate of 360 kHz/cm2. Taking into account the high spatial resolution (< 200 μm) and the operational stability of the MWPC detector as well as the results obtained on its high rate capability in our research we believe that this type of detector meets all requirements to TRD of the CBM project. 8 and ω resonance decay modes (G.Sharkov, ITEP) If resonance decays before in dense barionic matter Possible rescattering of hadronic daughters Reconstruction probability decrease for hadronic mode ω(782) π+π-π0, π+π-, π0 (c = 23 fm) φ(1020) (c = 44 fm) K+K-, η, e+e- e+ φ eφ η K e+e- φ η + K + - K φ hadronization β= 1/3 ω l,fm Kinetic freeze-out Calorimeter simulation and reconstruction (M.Prokudin, ITEP) Shower library •Fits exactly to the data •Any incident angle •checking analytical approximation quality LHCb inner. 4mm Near fibers 1cm Gray – MC. Black – data. Scale! 1cm Prototype. 0.5 mm Near fibers 1cm 10 Advanced digitization and hit finding in MUCH (M.Ryzhinskiy, SPbSPU) 11 On e/p identification: comparision of TRD prototype measurements with GEANT simulation at p=1.5 GeV/c (O.Denisova, JINR) •One cannot get a maximal value of pion’s suppression when using the LFR test, because the electron energy losses are described by a complex hypothesis – the sum of two distributions. •Using GEANT simulations were reproduced the results obtained on the basis of real measurements, and there was demonstrated that the procedure of preparation of data sets based on real measurements is a reason of getting erroneous, 12 overestimated results Time schedule Time schedule