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Многоцелевой детектор M ulti P urpose D etector (статус проекта). Введение Физические задачи первого этапа Концептуальная схема установки MPD «Барельная» часть MPD Торцевые части MPD Организационные аспекты Заключение. В. Кекелидзе, ОИЯИ. Физическая мотивация.
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Многоцелевой детектор MultiPurpose Detector (статус проекта) • Введение • Физические задачи первого этапа • Концептуальная схема установки MPD • «Барельная» часть MPD • Торцевые частиMPD • Организационные аспекты • Заключение В. Кекелидзе, ОИЯИ V.Kekelidze, Workshop at IHEP
Физическая мотивация • Планируется исследовать свойства адронов в веществе и состояния ядерного вещества, включая поиск возможных проявлений: - деконфаймента, - восстановления киральной симметрии, - фазовых переходов, - смешанной фазы и критической точки. • Исследования будут проводиться в процессах взаимодействий релятивиствских ионов - с атомнымвесом от 1 до 238 (U92+) - путем сканирования по энергии реакции в области SNN = 3-9 GeV • Эти исследования важны как для понимания природы взаимодействия тяжелых ионов, так и для решения вопросов космологии (эволюции Ранней Вселенной, формирования нейтронных звезд и др.) V.Kekelidze, Workshop at IHEP
Physics motivation V.Kekelidze, Workshop at IHEP
Physics motivation The phase diagram in terms of the reduced energy density The trajectories calculated with hybrid model • open markers: QGSM • filled markers: • evolution within • 3D relativistic hydrodynamics steps: 0.3 fm/c & 0.5 fm/c V.Kekelidze, Workshop at IHEP
MPD Collider NICAcomplex allocation V.Kekelidze, Workshop at IHEP
Collider NICAparameters V.Kekelidze, Workshop at IHEP
dedicated experiments • Fixed target experiments NA61 at SPS CERN and CBM at SIS100/300 GSI • advantages of collider experiments: • possibility to have 4pacceptance ! • energy scan do not introduce significant variation on critical density of detected particles • Collider experiments running at high energies: STAR & Fenix at RHIC BNL, ALICE at LHC CERN • STAR plans to run at low energies (SNN = 4-9 GeV, for U92+) Problem: luminocity falls down V.Kekelidze, Workshop at IHEP
Experimental Tasks – the first stage targets the effects to be studied on energy & centrality scanning: • Event-by-event fluctuation in hadron productions (multiplicity, Pt etc.) • HBT correlations indicating the space-time size of the systems involving π, K, p, Λ (possible changes close to the de-confinement point) • Directed & elliptic flows for various hadrons • Multi-strange hyperon production: yield & spectra (the probes of nuclear media phases) V.Kekelidze, Workshop at IHEP
MPD – conceptual design Initial constrains: • longitudinal (z-axis) space limited by ~ 800 cm between collider optics • radial scale limited by engineering problems & cost (R < 200 cm) Solution: • compact solenoid with major parts of detector working in the magnetic field • design of superconducting magnet with closed yoke geometry to provide homogeneous magnetic field V.Kekelidze, Workshop at IHEP
all B=0 Observables First stage of simulation based on UrQMD & GEANT4 in the framework of MPD-Root shell: • Au+Au collisions with total energy of 4.5 + 4.5 AGeV • Central interaction within b: 0 – 3 fm • Minimum bias within b: 0 – 15.8 fm • Collision rate at L=1027 cm-2s-1: ~ 6 kHz central collision |η| < 1,p>100 MeV/c charged particle multiplicity (primary) momentum spectrum <P>= 0.4 GeV/c ~ 450 V.Kekelidze, Workshop at IHEP
Observables Pseudorapidity spectra V.Kekelidze, Workshop at IHEP
Observables Charged particles Multiplicity V.Kekelidze, Workshop at IHEP
MPD – conceptual design General View V.Kekelidze, Workshop at IHEP
MPD – conceptual design • Defined as a compromise between: • TOF requirement • tracker resolution basic geometry preliminary • magnetic field formation • the cost 2700 limited by collider optics V.Kekelidze, Workshop at IHEP
Magnenic field • superconducting solenoidal magnet • magnetic field 0.5 T • cryostat inner radius ~ 1.5 m (region available for the detector) • iron yoke is used to form a homogeneous magnetic field • color step 5 Gauss (~1 pm) - good homogeneity feasible for TPC V.Kekelidze, Workshop at IHEP
MPD – conceptual design Magnetic field V.Kekelidze, Workshop at IHEP
MPD – conceptual design Towards 4p acceptance: to cover a wide pseudorapidity range V.Kekelidze, Workshop at IHEP
MPD Barrel part tracking, precise momentum measurement & particle ID in the region-1 < <1 • Major tracker - TPC • + Inner Tracker- silicon strip detector / micromegas chamber • for tracking close to the interaction region • + Outer Trackerstraw barrel (optional) • Time Of FlightRPC (+ start/stop sys.) for charged particle ID • ECAL shashlyk type - for e, , 0 reconstruction V.Kekelidze, Workshop at IHEP
TPC – major tracker V.Kekelidze, Workshop at IHEP
TPC – major tracker specification (preliminary) • Outer radius ~ 110 cm • Inner radius 20 cm • Drift length ~135 cm • Number of sections (each side) 12 • Total number of readout chambers 24 (12 – each side) • Drift time ~ 20-30 s • Multiplicity for charged particles (central collision) ~ 500 • Total pad/channels number ~ 80000 • dE/dx resolution ~ 6% (50 samples x 2cm) • Special resolution ( x R x z) 3 x 0.4 x 3 mm • Maximal rate 10 kHz V.Kekelidze, Workshop at IHEP
35 cm Inner Tracker (silicon strips) • Complementary detector for track precise reconstruction in the region close to the interaction piont • Cylindrical geometry (4 layers) covering the interaction region ~ 50 cm along the beam axis • Possible contribution to dE/dx measurements for charged particles V.Kekelidze, Workshop at IHEP
Inner Tracker - MMGC(optional) • Number of double mesh chambers: 32 • Covered area: 3,2 m2 • N of RO channels: 20000 V.Kekelidze, Workshop at IHEP
OuterTracker - Straw barrel (optional) to enhance tracking parameters in |η| < 1 12 x 2 (R+L) double modules occupancy ~ 4% for segmented straw with the lengths: 330mm (central), 500 mm & 700 mm V.Kekelidze, Workshop at IHEP
TOF Barrel system Time of Flight TOF detector covers the region |η| < 1 with an acceptance ~ 93% The barrel surface ~ 30 m2 (length 4 m, radius of 1,3 m) The counters are placed in 12 modules, 560 counters in total The total number of readout channels is 27600 Time resolution ~ 100 ps V.Kekelidze, Workshop at IHEP
the basic element of RPC multigap RPCs distribution in the module box. Distribution of RPCs in the barrel Time of Flight multigap RPC counter is 7 cm x 67 cm, it has 150 pads with size 2.3cm x 2 cm. V.Kekelidze, Workshop at IHEP
Time of Flight Specification: • the RPC TOF system looks like barrel with the length 4 m and radius of 1,3 m. • the barrel surface is about 33 m2 • the dimensions of one RPC counter is 7 cm x 100 cm it has 150 pads with size 2,3cm x 2 cm. • the full barrel is covered by 160 counters • the total number of readout channels is 24000 • Time resolution ~ 100 ps V.Kekelidze, Workshop at IHEP
Time of Flight track momenta mass reconstruction for central events V.Kekelidze, Workshop at IHEP
red blue Time of Flight momentum spectra ratios for primary K / particles no essential bias on momentum for the separation V.Kekelidze, Workshop at IHEP
0 1.0 2.0 GeV photon energy spectrum • 1000 1500 • photon multiplicity • (from π0 decay in red) Electromagnetic Calorimeter Photons in the barrel requires high granularity: average occupancy in barrel for 3x3 cm crystals< 3% V.Kekelidze, Workshop at IHEP
Electromagnetic Calorimeter Requirements for p0 reconstruction V.Kekelidze, Workshop at IHEP
ECal Shashlyk ECAL -Pb- scintillator 10x10 cm2 Module - 18 X0 ~ 30.6 cm AMPD read-out V.Kekelidze, Workshop at IHEP
ECal PbWO4 (optional) basic element -PbWO4 (3x3x16cm3), wrapped in Tyvek & coated with black tube a light detector is glued onto the outer face of the crystal One module (24x24x22cm3)- 64 crystals including light detectors & preamps The module has 0.5 mm thick walls of a folded Al plate fixed to the Al support In total 510 modules with 32640 crystals V.Kekelidze, Workshop at IHEP
MPD End-Capparts for tracking & momentum measurement at || >1 + reaction plane determination • End Cap TrackerStraw Wheels (stereo radial) • Beam Beam Countersfor centrality determination & reconstruction of the interaction point • + start /stop systemfor ToF • Zero Degree Calorimeter for centrality determination, measurement of fluctuations V.Kekelidze, Workshop at IHEP
ECT straw wheels occupancy /straw < 15 % V.Kekelidze, Workshop at IHEP
ECT straw wheel Stereo wheel construction: each stereo wheel contains 4 layers of radial straws with different orientation V.Kekelidze, Workshop at IHEP
ECT straw wheel Number of track hits = f(R) is related to reconstruction efficiency Pseudorapidity correlation with track hit numbers V.Kekelidze, Workshop at IHEP
ECT ECT TPC Track reconstruction efficiency ECT complements TPC to extend pseudorapidity range V.Kekelidze, Workshop at IHEP
R= 110 cm Expected number of charged track accepted vs. impact parameter (Hijing predictions). small tiles - within 12 cm diameter, large tiles x 4 larger . Beam Beam Counter Pseudorapidy region: 1.5 4.5 (out of the TPC acceptance) usable for centrality /min bias triggers V.Kekelidze, Workshop at IHEP
Zero Degree Calorimeter INR RAN • measurement of centrality: b ~ A - Nspect selection of centrality at trigger level • measurement of event-by-event fluctuations to exclude the fluctuation of participants • monitor of beam intensity by detecting the neutrons from electromagnetic dissociation • εe / εh = 1 - compensated calorimeter • Lead / Scintillator sandwich V.Kekelidze, Workshop at IHEP
Beam hole X Z Zero Degree Calorimeter Full beam intensity. -minimum 16 modules. V.Kekelidze, Workshop at IHEP
DAQ & Computing • events ~2 10 10 • disk space 10 000 TB • PC’s ~ 1800 V.Kekelidze, Workshop at IHEP
Engineering + auxiliaries Require essential reconstruction of the intersection area to provide access for works & for necessary auxiliaries V.Kekelidze, Workshop at IHEP
Cost Estimation in k$ (very preliminary) Magnet - 3 138 TPC - 9 500 IT (SSD /MM) - 3 600 / 750 OT - 4 000 TOF - 4 000 ECAL (shashlyk / crystal) - 5 624 / 14 356 ECT - 7 900 BBC - 390 TDAQ - 3 000 ZDC - 598 Slow Control - 280 Computing - 1 460 Engineering - 2 000 _________________ _________ Total 41 490 V.Kekelidze, Workshop at IHEP
MPD – organizational aspects • At first approximation - all sub-detectors could be designed & constructed at JINR based on the existing expertise & infrastructure • some sub-detectors could have alternative designs in order to provide possibility for potential collaborators to substitute/accomplish corresponding groups in future • The first realistic draft of the Letter of Intent & the rough cost estimation =- are available V.Kekelidze, Workshop at IHEP
MPD – Collaboration • Joint Institute for Nuclear Research • Institute for Nuclear Research Russian Academy of Science • BogolyubovInstitute for Theoretical Physics, NASUk • Nuclear Physics Institute of MSU, RF • Institute of Allied Physics, Academy of Science Moldova • __________///________ open for extension A consortium involving GSI, JINR & other centers for IT module development & production is at the organizational stage V.Kekelidze, Workshop at IHEP
MPD Collaboration V.Kekelidze, Workshop at IHEP
Заключение • Письмо о намерениях (Letter of Intent) - подготовлено и доступно • Работа над проектом продолжается - моделирование с целью оптимизации параметров • интенсифицируются R & D, • (особенно по ключевым детекторам) • Ведутся переговоры по расширению участников проекта и организации соответствующего сотрудничества • Проведен ряд организационных мероприятий с рамках ОИЯИ с целью укрепления коллективов, участвующих в работе над проектом • Выделены дополнительные ресурсы для работы V.Kekelidze, Workshop at IHEP
Spin Program atNICA in preparation V.Kekelidze, Workshop at IHEP
Spare V.Kekelidze, Workshop at IHEP
Possible indication on phase transition measurements of related yields for charged kaons & pions Some enhancement is indicated in the energy region around ~ Елаб = 30 А ГэВ V.Kekelidze, Workshop at IHEP