Post on 15-Jan-2016
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APMP, Belarus Gomel, July 26, 2007
Relativistic Nuclear Physics
from SPS to NICA
O.V. Rogachevsky for
NICA/MPD working group
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APMP, Belarus Gomel, July 26, 2007
Physicists have long thought that a new state of matter could be reached if the short range repulsive forces between nucleons could be overcome and if squeezed nucleons would merge into one another. Present theoretical ideas provide a more precise picture for this new state of matter: it should be a quark-gluon plasma (QGP), in which quarks and gluons, the fundamental constituents of matter, are no longer confined within the dimensions of the nucleon, but free to move around over a volume in which a high enough temperature and/or density prevails. This plasma also exhibits the so-called "chiral symmetry" which in normal nuclear matter is spontaneously broken, resulting in effective quark masses which are much larger than the actual masses. For the transition temperature to this new state, lattice QCD calculations give values between 140 and 180 MeV, corresponding to an energy density in the neighborhood of 1 GeV/fm3, or seven times that of nuclear matter. Temperatures and energy densities above these values existed in the early universe during the first few microseconds after the Big Bang.
Quark Gluon Plasma
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Phase transitions
the end point of a 1st order line = a critical point of the 2nd order (at the critical point the phases start to be indistinguishable)
Phase diagram of water Phase diagram of nuclear matter
critical point 1st order phase
transition
cross-over
The qualitative shape of the equation of state for hot hadronic matter at zero chemical potential. Fig. (a) refers to a first order phase transition with metastable states (dashed parts of the curves), Fig. (b) corresponds to a smooth transition.
L. Van Hove Z. Phys. C 27, 135-144 (1985)
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Phase transition in hadronic matter
Theoretical phase diagram of nuclear matter for two massless quarks as a function of temperature T and baryon chemical potential µ
K. Rajagopal, Acta Phys. Polon. B31 (2000) 3021
Lattice QCD results for the energy density ε/ T 4 as a function of the temperature scaled by the critical temperature TC . The arrows on the right side indicating the values for the Stefan-Boltzmann limit.
F. Karsch, Lect. Notes Phys. 583 (2002) 209
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APMP, Belarus Gomel, July 26, 2007
CERN lead beam programme
Time: from 1994 to 1999
Seven large experiments: NA44, NA45/CERES, NA49, NA50, NA52/NEWMASS, WA97/NA57, and WA98
There were multipurpose detectors to measure simultaneously and correlate several of the more abundant observables and dedicated experiments to detect rare signatures with high statistics
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NA49
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Evidence for a New State of Matter: Results From the CERN Lead Beam Programme
A common assessment of the collected data leads us to conclude that we now have compelling evidence that a new state of matter has indeed been created, at energy densities which had never been reached over appreciable volumes in laboratory experiments before and which exceed by more than a factor 20 that of normal nuclear matter. The new state of matter found in heavy ion collisions at the SPS features many of the characteristics of the theoretically predicted quark-gluon plasma.
The evidence for this new state of matter is based on a multitude of different observations. Many hadronic observables show a strong nonlinear dependence on the number of nucleons which participate in the collision. Models based on hadronic interaction mechanisms have consistently failed to simultaneously explain the wealth of accumulated data. On the other hand, the data exhibit many of the predicted signatures for a quark-gluon plasma. Even if a full characterization of the initial collision stage is presently not yet possible, the data provide strong evidence that it consists of deconfined quarks and gluons.
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APMP, Belarus Gomel, July 26, 2007
Striking New STAR Results
STARSTAR
Pedestal&flow subtractedIn central Au+Au collisions:Strong suppression of inclusive hadron productionDisappearance of the away-side jet
d+Au looks like p+pJet quenching in the dense medium
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RHIC 2005 White papersFormation of dense partonic matter in relativistic nucleus-nucleus collisions at RHIC: Experimental evaluation by the PHENIX collaboration.
arXiv:nucl-ex/0410003
Experimental and Theoretical Challenges in the Search for the Quark Gluon Plasma: The STAR Collaboration’s Critical Assessment of the Evidence from RHIC Collisions. arXiv:nucl-ex/0501009
The PHOBOS perspective on discoveries at RHIC. Nuclear Physics A
Quark–gluon plasma and color glass condensate at RHIC? The perspective from the BRAHMS experiment. Nuclear Physics A 757 (2005) 1–27
The theory-experiment comparison indicates that central Au+Au collisions at RHIC produce a unique form of strongly interacting matter, with some dramatic and surprisingly simple properties. A number of the most striking experimental results have been described to a reasonable quantitative level, and in some cases even predicted beforehand, using theoretical treatments inspired by QCD and based on QGP formation in the early stages of the collisions.
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M.G.Gorenstein JINR Winter school, 2006
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Nu Xu “Critical Point and Onset of Deconfinment”, GSI, July 2007
STAR Low Energy Commissioning √s NN = 9.2 GeV Au+Au Collisions taken on June 7, 2007
RHIC at 9.2 GeV
- Au+Au Collisions at √s NN = 22, 9.2 GeV are done. - Next: ~ 5 GeV, in 2008!
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Compressed Barionic Matter
Dynamical trajectories for central (b = 2fm) Au + Au collisions in T − nB (left )and T −µB (right) plane for various bombarding energies calculated within the relativistic 3-fluid hydrodynamics. Numbers near the trajectories are the evolution time moment. Phase boundaries are estimated in a two-phase bag model.
Y.B. Ivanov, V.N. Russkikh and V.D. Toneev,
nucl-th/0503088.
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FAIR at GSI
Construction costs: 1187 M€
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Compressed Barionic Matter (CBM)
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CBM Physics
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Research Program & Expert's Report
Organizing Committee
Photographs
Program
Talks
Round Table Discussion
Searching for the mixed phase of strongly interacting matter at the JINR Nuclotron
July 7 - 9, 2005
http://theor.jinr.ru/meetings/2005/roundtable/
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http://theor.jinr.ru/meetings/2006/roundtable/
Round Table Discussion II
Searching for the mixed phase of strongly interacting matter at the JINR Nuclotron:Nuclotron facility development
JINR, Dubna, October 6-7, 2006
Conceptional project Design and construction ofNuclotron-based Ion Collider fAcility (NICA) and Multi-Purpose Detector (MPD)
http://theor.jinr.ru/meetings/2006/roundtable/booklet.html
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NICA/MPD goals and physics problems
the second stage ♣ Electromagnetic probes (photons and dileptons)
Study of in-medium properties of hadrons and nuclear equation of state, including a search for possible signs of
deconfinement and/or chiral symmetry restoration phase transitions and QCD critical endpoint in the region of √s NN=4-9 GeV
by means of careful scanning in beam energy and centrality of excitation functions for
the first stage♣ Multiplicity and global characteristics of identified hadrons including multi-strange particles♣ Fluctuations in multiplicity and transverse momenta ♣ Directed and elliptic flows for various hadrons♣ HBT and particle correlations
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APMP, Belarus Gomel, July 26, 2007
NICA general layout
Circumference 251.2 m
Averaged luminosity (1-1.5)1027 cm-2s-1
Cost saving factors: •No new buildings, no additional power lines. • No extra heat, water cooling power.
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NICA scheme
Booster (30 Tm)5 single-turn injections,
storage of 8×109 at electron cooling
bunching & accelerationup to 590 MeV/u
Nuclotron (45) Tm)injection of one bunch
of 3×109 ions,acceleration up to
3.5 GeV/u max.
Collider (37 45 Tm)Storage of
20 bunches 2.5109 ions per ring at 3.5 GeV/u max.,
electron and/or stochastic cooling
Injector: 2×109 ions/pulse of 238U30+ at energy 5 MeV/u
IP-1 IP-2
Stripping (eff. 40%) 238U32+ 238U92+
Two collider rings
2x20 injection cycles
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Preinjector + Linac
Cost estimates
Conceptual design ~ $ 10 k
Design, manufacturing at IHEP
and assembling at JINR ~ $ 10 M
Injector concept
KRION suspended up to 200 kV
RFQ pre-accelerator
Linac (unique design, “H-wave” type)
Equipment to be delivered by IHEP
1) RFQ + Linac structures
2) RF generators
3) Diagnostic system
4) Control system
5) Water cooling system
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APMP, Belarus Gomel, July 26, 2007
Booster
“Warm” booster
on base
of the Synchrophasotron
B = 30 Tm, C = 210 m1) 5 single-turn injections 2) Storage of 8×109 238U32+ at electron
cooling3) bunching 4) Acceleration up to 590 MeV/u5) Extraction & stripping
Nuclotron
Booster
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APMP, Belarus Gomel, July 26, 2007
Booster (Contnd)
Cost estimate, $ M(the Central Machinery Workshop of JINR)
1) One dipole magnet of 1.36 T max field 0.315
2) 70 dipole magnets 2.2
3) Total cost of the booster ~ 8.0
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Collider Electron cooling system
MPD
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Collider parameters
Ring circumference, m 251.2
Ion kinetic energy, E [GeV/u] 3.5
Particle number per bunch, Nion/bunch 2.0×109
Bunch number, nbunch 20
Horizontal emittance, [ mm mrad] 0.7
Momentum spread, p/p 0.001
IBS life time [sec] 100
Beta function at interaction point, * [m] 0.5
RF voltage, U_rf [kV] 200
Laslett tune shift, Q 0.0044
Beam-beam parameter 0.009
Peak luminosity, L [cm-2s-1] 2×1027
Average luminosity, L [cm-2s-1] (11.5)×1027
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APMP, Belarus Gomel, July 26, 2007
NICA Cost Estimates ($M)
KRION + HV “platform” 0.25 Injector (IHEP design) 10Booster 8Collider 2 x 10
Total ~ 40
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TOF F
Silicon Vertex System
TPC
Zero Degree Calorimeter
TOF
MPD general layout
Simulated tracks from U+U collision with √sNN= 9 GeV
energy with UrQMD model.
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350 cm
25 cm
TOF Start
TOF RPC
TOF Start
Tracker (TPC)
SVD 4 planes
ECal
Interaction region ~50 cm
Forward ECAL
30 c
m
ZDC
300 cm
200
cm
Multi-Purpose Detector
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MPD cost estimate ($M) ~ 25 Silicon vertex detector 4.8 Time projection chamber 5.0 TOF system 4.0 EM calorimeter barrel 3.5
Required MPD parameters
• |y|<2 acceptance and 2π continuous azimuthal coverage • High track reconstruction efficiency • Adequate track length for tracking, momentum measurement and particle
identification • Momentum resolution Δp/p<0.02 for 0.1< p<2 GeV/c • Two-track resolution providing a momentum difference resolution of few
MeV/c for HBT correlation studies • Determination of the primary vertex better than 200m for high momentum
resolution to be able to identify particles from the primary interaction • Determination of secondary vertices for detecting the decay of strange particles such as Λ, Κ0
s, Ξ±, Ω-
• The fraction of registered vertex pions > 75%
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• Stage 1: years 2007 – 2008- Upgrate and Development of the Nuclotron facility - Preparation of Technical Design Report - Start for prototyping of the MPD and NICA elements
• Stage 2: years 2008 – 2012 - Design and Construction of NICA and MPD detector - Design and Construction of the Booster Accelerator
• Stage 3: years 2010 – 2013 - Assembling
• Stage 4: year 2013 - Commissioning
The Project Milestones
http://theor.jinr.ru/meetings/2008/
Round Table Discussion III, Searching for the mixed phase of strongly interacting QCD matter at the NICA/MPD (JINR,Dubna) January, 2008
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NICA
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hea
t
NICA
compression
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Ion SourceIon Sources comparison
(Experimental results)
Ion source KRION, Au30+ ECR, Pb27+
Peak ion current, mA 1.2 0.2
Pulse duration, s 8 200
Ions per pulse 2109 11010
Ions per sec 2.5x108 5x107
Norm. rms emittance 0.150.3 0.150.3
Repetition rate, Hz 60 30
Crucial parameter: Ions per sec!
Thus, KRION has very significant advantage!
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Booster (Contnd)
Booster
Base of the Synchrophasotron
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Injector: Ion Source + Preinjector + Linac
d 238U32+
5 MeV/u
31 m
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APMP, Belarus Gomel, July 26, 2007
NICA scheme (Contnd)
2 x 41010 ions of 238U92+
t
Time Table of The Storage Process
3.5 GeV/u
590 MeV/u
5 MeV/u
300 keV/u
20 keV/u 8s 0.1s 1s 3s 2 min
electroncooling5 cycles
of injection
2x20 cycles of injection
KRION RFQ LINAC Booster Nuclotron Collider
Eion/A
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Assembling of the ZDC at INR (Troitsk)
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The Nuclotron 6 A·GeV synchrotron based on unique fast-cycling superferric magnets, was designed and constructed at JINR for five years (1987-1992) and put into operation in March 1993. The annual running time of 2000 hours was provided during the last years.
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Preinjector + LinacNegotiations at IHEP (Protvino)
21-22 June 2007
Prototype of the linac for CERN
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