摘要：
Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (
$\sqrt{s_{NN}}=$
2.7--4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (
$\mu_B > 500$
MeV), effects of chiral symmetry, and the equation of state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2024, in the context of the worldwide efforts to explore high-density QCD matter.
期刊：
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT,2014年735:157-162 ISSN：0168-9002
通讯作者：
Zhang, Fan
作者机构：
[Huang, Guangming; Zhou, Daicui; Zhang, Fan] Cent China Normal Univ, Key Lab Quark & Lepton Phys MOE, Wuhan 430079, Peoples R China.;[Zhou, Daicui; Zhang, Fan] Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.;[Huang, Guangming; Zhang, Fan] Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan 430079, Peoples R China.;[Muller, Hans; Martinez, Alfonso Tarazona; Martoiu, Sorin] CERN, PH Dept, CH-1211 Geneva 23, Switzerland.;[Silvermyr, David; Awes, Terry. C.] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA.
通讯机构：
[Zhang, Fan] C;Cent China Normal Univ, Key Lab Quark & Lepton Phys MOE, Wuhan 430079, Peoples R China.
关键词：
ALICE calorimeter;GTL bus;Point-to-point links;Scalable Readout Unit;Event readout rate
摘要：
It is anticipated that the LHC will deliver Pb + Pb collisions at a minimum bias interaction rate of about 50 kHz after the second long shutdown of the LHC in 2018. This will be roughly two orders of magnitude greater than the current data recording rate capability of the ALICE experiment. Therefore a major upgrade of the ALICE detector is planned for the next shutdown to enable ALICE to record data at the full Pb + Pb minimum bias interaction rate delivered by the LHC. A new point-to-point readout system for the electromagnetic calorimeter (EMCal) of ALICE has been developed, to replace the legacy readout bus, that essentially accomplishes this goal, and is being installed during the current LHC shutdown (2013-2014). The new readout uses the existing EMCal front end electronics yet provides more than an order of magnitude decrease in the readout Lime, to about 21 mu s, with modest cost and effort. (C) 2013 Elsevier B.V. All rights reserved.
作者：
Xiang, C. Z.*;Herrmann, N.;Deppner, I.;Loizeau, P. -A.;Wisniewski, K.;...
期刊：
Journal of Instrumentation,2013年8(2):P02002 ISSN：1748-0221
通讯作者：
Xiang, C. Z.
作者机构：
[Xiang, C. Z.; Zhou, D. C.] Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan 430079, Peoples R China.;[Xiang, C. Z.; Zhou, D. C.] Cent China Normal Univ, Minist Educ, Key Lab Quark & Lepton Phys, Wuhan 430079, Peoples R China.;[Wisniewski, K.; Zhang, Y. P.; Herrmann, N.; Xiang, C. Z.; Deppner, I.; Loizeau, P. -A.] Heidelberg Univ, Inst Phys, D-69120 Heidelberg, Germany.;[Fruehauf, J.; Mueller, W. F. J.; Linev, S.] GSI Helmholtz Ctr Heavy Ion Res GmbH, D-64291 Darmstadt, Germany.;[Manz, S.] Kirchhoff Inst Phys, D-69120 Heidelberg, Germany.
通讯机构：
[Xiang, C. Z.] C;Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan 430079, Peoples R China.
关键词：
Control and monitor systems online;Data processing methods;Online farms and online filtering
摘要：
The PHOS level-0 trigger provides a minimum bias trigger for p-p collisions and information for a level-1 trigger at both p-p and Pb-Pb collisions. There are two level-0 trigger generating algorithms under consideration: the Direct Comparison algorithm and the Weighted Sum algorithm. In order to study trigger algorithms via simulation, a simplified equivalent model is extracted from the trigger electronics to derive the waveform function of the Analog-or signal as input to the trigger algorithms. Simulations shown that the Weighted Sum algorithm can achieve higher trigger efficiency and provide more precise single channel energy information than the direct compare algorithm. An energy resolution of 9.75 MeV can be achieved with the Weighted Sum algorithm at a sampling rate of 40 Msps (mega samples per second) at 1 GeV. The timing performance at a sampling rate of 40 Msps with the Weighted Sum algorithm is better than that at a sampling rate of 20 Msps with both algorithms. The level-0 trigger can be delivered to ALICE CTP within 800 ns with a timing uncertainty of 2 LHC bunch crossing cycles. (C) 2010 Elsevier B.V. All rights reserved.
作者：
Yin, Z. B.*;Liu, L. J.;Muller, H.;Rohrich, D.;Sibiryak, I.;...
期刊：
Journal of Physics: Conference Series,2011年293(1) ISSN：1742-6588
通讯作者：
Yin, Z. B.
作者机构：
[Zhang, F.; Yin, Z. B.; Wang, Y. P.; Wang, D.; Zhou, D. C.] Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.
通讯机构：
[Yin, Z. B.] H;Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.
会议名称：
14th International Conference on Calorimetry in High Energy Physics (CALOR 2010)
会议时间：
MAY 10-14, 2010
会议地点：
Inst High Energy Phys, Beijing, PEOPLES R CHINA
会议主办单位：
Inst High Energy Phys
会议论文集名称：
Journal of Physics Conference Series
摘要：
The photon spectrometer (PHOS) in the ALICE experiment at LHC is a PbWO<inf>4</inf> crystal based electromagnetic calorimeter, dedicated to measuring photons, π°'s and η's over a broad pT range from about 100 MeV/c to 100 GeV/c with the best possible energy and position resolution. The front-end electronics of the PHOS is thus required to cover a large dynamic range, to achieve a timing resolution better than ∼2 ns in order to discriminate against 1-2 GeV/c (anti-)neutrons, and to provide high pT trigger to select rare high pT events. In this paper, we present the full PHOS readout system, including the avalanche photo-diode, the low noise charge sensitive preamplifier, the 32 channel front-end electronics card, the trigger region unit and the trigger OR module. Results from PHOS commissioning with beam particles and cosmic rays will also be presented to address the performance of the PHOS readout electronics.
作者机构：
[del Valle, Z. Conesa; Garcia, G. Martinez] Univ Nantes, Ecole Mines, Subatech CNRS IN2P3, Nantes, France.;[Dainese, A.] Ist Nazl Fis Nucl, Lab Nazl Legnaro, I-35020 Padua, Italy.;[Zhou, D. C.; Ding, H. -T.] Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.
通讯机构：
[Garcia, G. Martinez] U;Univ Nantes, Ecole Mines, Subatech CNRS IN2P3, Nantes, France.
关键词：
Heavy quarks;Muons;Quark-gluon plasma;Relativistic heavy-ion collisions;Weak gauge bosons
摘要：
We study the nuclear modification factors R-AA and R-CP of the high transverse momentum (5 < p(t) < 60 GeV/c) distribution of muons in Pb-Pb collisions at LHC energies. We consider two pseudo-rapidity ranges covered by the LHC experiments: |eta| < 2.5 and 2.5 < eta < 4. Muons from semi-leptonic decays of heavy quarks (c and b) and from leptonic decays of weak gauge bosons (W and Z) are the main contributions to the muon p(t) distribution above a few GeV/c. We compute the heavy quark contributions using available pQCD-based programs. We include the nuclear shadowing modification of the parton distribution functions and the in-medium radiative energy loss for heavy quarks, using the mass-dependent BDMPS quenching weights. Muons from W and Z leptonic decays, that dominate the yield at high p(t), can be used as a medium-blind reference to observe the medium-induced suppression of beauty quarks. (C) 2008 Elsevier B.V. All rights reserved.
作者机构：
Oak Ridge Natl Lab, Dept Phys, Oak Ridge, TN 37831 USA.;Acad Sinica, Shanghai Inst Nucl Res, Div Nucl Phys, Shanghai 201800, Peoples R China.;Hua Zhong Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.;[Xu, XM] Oak Ridge Natl Lab, Dept Phys, Bldg 6011,MS-6373,POB 2008, Oak Ridge, TN 37831 USA.
通讯机构：
[Xu, XM] O;Oak Ridge Natl Lab, Dept Phys, Bldg 6011,MS-6373,POB 2008, Oak Ridge, TN 37831 USA.
关键词：
charmonium dissociation cross sections;proton-nucleus reactions;J/psi,psi ' and chi(c) suppressions
摘要：
Charmonium dissociations by nucleons are first studied from a quark-quark potential in combination with quark exchange mechanism. Wave functions of nucleons and charmed baryons involved in dissociation reactions result from a fit to mass splittings of baryons with spins and 3/2. Transverse momentum and x(F) distributions of prompt J/psi produced in 800 GeV/c p-Be collisions are calculated by using NRQCD dsigma/d (t) over cap for parton-parton scatterings and taking into account initial transverse-momentum distributions of partons inside nucleons. We emphasize that the new dissociation cross sections of J/psi, psi' and chi(cJ) give rise to remarkable differences of J/psi, psi' and chi(c) suppressions at large negative x(F) in p-W collisions at root(s)NN = 38.8 and 41.6 GeV and p-Au collisions at root(s)NN = 130 GeV. (C) 2002 Elsevier Science B.V. All rights reserved.
摘要：
Scaled factorial moment analysis for the multiplicity distribu- tions of shower particles in the pseudorapidity phase space has been done. An evidence for the presence of dynamical uctuations has been shown for the non-peripheral interactions of28Si+Ag(Br) at 14.6 A GeV/c and 4.5 A GeV/c.The results have been compared with the values obtained from data sample calculated by cascade-evaporation model.
期刊：
EUROPEAN PHYSICAL JOURNAL A,1999年5(4):429-440 ISSN：1434-6001
通讯作者：
Adamovich, MI
作者机构：
PN Lebedev Phys Inst, Moscow 117924, Russia.;Inst High Energy Phys, Alma Ata, Kazakhstan.;Acad Sinica, Inst High Energy Phys, Beijing, Peoples R China.;Inst Space Sci, Bucharest, Romania.;Panjab Univ, Dept Phys, Chandigarh 160014, India.
摘要：
The experimental data on the interactions of 10.6A GeV gold nuclei in nuclear emulsions are analyzed with particular emphasis of target separation interactions and study of critical exponents. Charged fragment moments, conditional moments as well as two and three - body asymmetries of the fast moving. projectile particles are determined in terms of the total charge remaining bound in the multiply charged projectile fragments. Some differences in the average yields of helium nuclei and heavier fragments are observed, which may be attributed to a target effect. However, two and three-body asymmetries and conditional moments indicate that the breakup mechanism of the projectile seems to be independent of target mass. We looked for evidence of critical point observable in finite nuclei by study the resulting charged fragments distributions. We have obtained the values for the critical exponents γ, β and τ and compare our results with those at lower energy experiment (1.0A GeV data). The values suggest that a phase transition like behavior, is observed.
作者机构：
CCAST, World Lab, Beijing 100080, Peoples R China.;China Inst Atom Energy, Beijing 102413, Peoples R China.;Huazhong Normal Univ, Inst Particle Phys, Beijing 430079, Peoples R China.;Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90025 USA.;Acad Sinica, Inst Theoret Phys, Beijing 100080, Peoples R China.
通讯机构：
[Sa, BH] C;CCAST, World Lab, POB 8730, Beijing 100080, Peoples R China.
摘要：
The idea that the reduction of the strange quark suppression in string fragmentation leads to the enhancement of strange particle yield in nucleus-nucleus collisions is applied to study the singly and multiply strange particle production in p-Pb and Pb-Pb collisions at 158A GeV/c. In this mechanism the strange quark suppression factor is related to the effective string tension, which increases in turn with the increase of the energy, the centrality, and the mass of colliding system. The WA97 observation that the strange particle enhancement increases with the increasing centrality and the increasing strange quark content in multiply strange particles in Pb-Pb collisions with respect to p-Pb collisions was reproduced reasonably well.
摘要：
The nuclear emulsion was exposed at CERN by the lead projectile at 160 A GeV. The angles between any pair of fragments with Z = 2 - 4 have been measured in the emulsion plane for the events which did not contain heavy fragments. The constant characterizing the normal angle (cp) distribution of the fragment momentum projection onto the emulsion plane with respect to initial projectile momentum Po is found to be sigma(phi) = (0.37 +/- 0.02) mrad. Corresponding value sigma(o) = (121 +/- 6) MeV/c of nucleon momentum distribution in the lead nucleus coincides with that expected from Fermi momentum distribution for this nucleus. The peak in the pair-angle distribution of double-charged fragments, Be-8 --> 2 alpha, is presented for the region of small angles (< 0.1 mrad). The fraction of alpha-particles coming from the decay of the ground state Be-8 is found to be (13 +/- 2)% of their whole number.
会议名称：
XXVIIth International Symposium on Multiparticle Dynamics
会议时间：
SEP 08-12, 1997
会议地点：
INFN, NATL LABS, FRASCATI, ITALY
会议主办单位：
PN Lebedev Phys Inst, Moscow 117924, Russia.^High Energy Phys Inst, Almaty, Kazakhstan.^Acad Sinica, Inst High Energy Phys, Beijing, Peoples R China.^Panjab Univ, Dept Phys, Chandigarh 160014, India.^Hunan Educ Inst, Dept Phys, Changsha, Hunan, Peoples R China.^Joint Nucl Res Inst, Dubna, Russia.^Univ Rajasthan, Dept Phys, Jaipur 302004, Rajasthan, India.^Univ Jammu, Dept Phys, Jammu 180004, India.^Safarik Univ, Dept Nucl Phys & Biophys, Kosice, Slovakia.^Shanxi Normal Univ, Dept Phys, Linfen, Shanxi, Peoples R China.^Univ Lund, Dept Phys, Lund, Sweden.^Univ Marburg, Fachbereich Phys, D-3550 Marburg, Germany.^Univ Washington, Dept Phys, Seattle, WA 98195 USA.^Inst Phys Nucl, Tashkent, Uzbekistan.^Phys Tech Inst, Tashkent, Uzbekistan.^Huazhong Normal Univ, Inst Particle Phys, Wuhan, Hubei, Peoples R China.^St Petersburg Nucl Phys Inst, St Petersburg, Russia.
摘要：
Angular distributions of charged particles produced in O-16 and S-32 collisions with nuclear track emulsion were studied at momenta 4.5 and 200 A GeV/c. Comparison with the angular distributions of charged particles produced in proton-nucleus collisions at the same momentum allows to draw the conclusion, that the angular distributions in nucleus-nucleus collisions can be seen as superposition of the angular distributions in nucleon-nucleus collisions taken at the same impact parameter b(NA), that is mean impact parameter between the participating projectile nucleons and the center of the target nucleus.
摘要：
The complete charge distribution of products from Au nuclei fragmenting in nuclear emulsion at 10.7A GeV has been measured. Multiplicities of produced particles and particles associated with the target source are used to select peripheral and central events. A statistical analysis, based on event-by-event charge distributions, show that a population of subcritical, critical and supercritical events, i.e. a phase transition like behaviour, is observed among peripheral collisions.
摘要：
Using emulsion detectors a transverse-momentum analysis of projectile fragments has been performed in Au induced nuclear interactions at 11.6 A GeV/c. Evidence for collective flow of the projectile fragments has been obtained. Angular distributions of the principal vectors of projectile and target fragments have shown strong azimuthal correlation.
作者机构：
[Adamovich, MI] Inst High Energy Phys, Alma Ata, Kazakhstan.;Acad Sinica, Inst High Energy Phys, Beijing, Peoples R China.;Inst Gravitat & Space Res, Bucharest, Romania.;Panjab Univ, Dept Phys, Chandigarh 160014, India.;Hunan Educ Inst, Dept Phys, Changsha, Hunan, Peoples R China.
通讯机构：
[Adamovich, MI] I;Inst High Energy Phys, Alma Ata, Kazakhstan.
摘要：
We analyse the multifractal structure of moments G(q) in terms of a new variable X on data of (197)AU, S-32, and O-16 induced interactions with emulsion nuclei and Monte Carlo generated samples. The dynamical properties of the produced particles are mapped onto multifractal spectra. We compare In(G) in experimental data of Au-197, S-32, and O-16 with pure statistical fluctuations. It is shown that the stochasticity plays an important role for the G-moments.
作者机构：
ACAD SINICA, INST HIGH ENERGY PHYS, BEIJING, PEOPLES R CHINA.;INST GRAVITAT & SPACE RES, BUCHAREST, ROMANIA.;PANJAB UNIV, DEPT PHYS, CHANDIGARH 160014, INDIA.;HUNAN EDUC INST, DEPT PHYS, CHANGSHA, HUNAN, PEOPLES R CHINA.;JOINT INST NUCL RES DUBNA, LAB HIGH ENERGIES, DUBNA, RUSSIA.
通讯机构：
[Adamovich, MI] I;INST HIGH ENERGY PHYS, ALMATY, KAZAKHSTAN.
摘要：
Angular distributions of projectile-associated He fragments from Pb induced reactions on stationary Pb target at 158 A GeV/c incident momentum are reported. The precision of the angular measurements was about ±0.01 mrad. Two emission components are appearing in the projected angular spectra of the He particles, one representing fragmentation at Fermi momentum scale, while the other one exhibits large transverse momentum transfer. By scaling with the incident momentum the angular spectra of He particles are compared with earlier reported measurements of Au on Au interactions at 11.6 A GeV/c. The pT spectrum of the He particles appears the same for the two cases.
期刊：
EUROPEAN PHYSICAL JOURNAL A,1997年358(3):337-351 ISSN：1434-6001
通讯作者：
Adamovich, MI
作者机构：
INST HIGH ENERGY PHYS,ALMATY,KAZAKHSTAN.;ACAD SINICA,INST HIGH ENERGY PHYS,BEIJING,PEOPLES R CHINA.;PANJAB UNIV,DEPT PHYS,CHANDIGARH 160014,INDIA.;HUNAN EDUC INST,DEPT PHYS,CHANGSHA,PEOPLES R CHINA.;JOINT INST NUCL RES,LAB COMP TECH,DUBNA,RUSSIA.
摘要：
Complex analysis of Gold interaction with photoemulsion nuclei at 10.7 GeV/nucleon has been performed. The data obtained were compared with a modified FRITIOF model which allowance is made for exitation of nuclear residuals (after interaction). A comparison was also made with cascade-evaporation model. Experimental data contradict the CEM supposition of fast resonance decay and complete cascading. The modified FRITIOF model fairly well reproduces experimental observations. According to the model the production mechanism of charged particles must remain unchangable in the 4-200 GeV/n energy range.
