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The Nuclotron-based Ion Collider fAcility (NICA) project is under development at JINR (Dubna). The general goals of the project are to provide colliding beams for experimental studies of both hot and dense strongly interacting baryonic matter and spin physics (in collisions of polarized protons and deuterons). The first program will require the running of heavy-ion mode in the energy range of $\sqrt{s_{NN}} = 4-11$ GeV at luminosities up to $ L = 1\cdot 10^{27}$ cm s for Au nuclei (see details in sect. 4). This stage of the project will be preceded by fixed target experiments with the heavy-ion beam to be extracted from the Nuclotron at kinetic energies up to 4.5 GeV/u. The polarized beam mode is proposed to be used in the energy range of $ \sqrt{s_{NN}} = 12-27$ GeV (protons) at luminosities up to $ 1\cdot 10^{32}$ cm s. This report contains a brief description of the facility scheme and characteristics in the heavy-ion operation mode, the description of the MultiPurpose Detector (MPD), and characteristics of the reactions of the colliding ions, which will allow us to detect the mixed phase formation. The plans and status of the project development are presented. [ABSTRACT FROM AUTHOR]

The particle correlations at small relative velocities are sensitive to the space—time characteristics of the production processes on a femtometer scale owing to the effects of quantum statistics and finalstate interaction. Though the final—state interaction complicates the correlation analysis, it is an important source of information allowing for coalescence femtoscopy, correlation femtoscopy with unlike particles including access to the relative space—time asymmetries in particle production, and a study of strong interactions between specific particles. I will briefly discuss the history and basics of correlation femtoscopy, some of the recent results from femtoscopy of relativistic heavy-ion collisions, and their consequences. [ABSTRACT FROM AUTHOR]

One of the basic facilities at the Joint Institute for Nuclear Research (JINR) in Dubna is the 6 A GeV Nuclotron, which has replaced the old weak focusing 10-GeV proton accelerator Synchrophasotron. The first relativistic nuclear beams with the energy of 4.2 A GeV were obtained at the Synchrophasotron in 1971. Since that time, relativistic nuclear physics has been one of the main directions of the JINR research program. In the coming years, the new JINR flagship program assumes the experimental study of hot and dense strongly interacting QCD matter at the new JINR facility. This goal is proposed to be reached by (i) development of the existing Nuclotron accelerator facility as a basis for generation of intense beams over atomic mass range from protons to uranium and light polarized ions, (ii) design and construction of the Nuclotron-based heavy Ion Collider fAcility (NICA) with the maximum nucleon-nucleon center-of-mass collision energy of √ s NN = 9 GeV and averaged luminosity 1027 cm−2 s−1, and (iii) design and construction of the Multipurpose Particle Detector (MPD) at intersecting beams. Realization of the project will lead to unique conditions for research activity of the world community. The NICA energy region is of major interest because the highest nuclear (baryonic) density under laboratory conditions can be reached there. Generation of intense polarized light nuclear beams aimed at investigation of polarization phenomena at the Nuclotron is foreseen. [ABSTRACT FROM AUTHOR]

For the decay of two identical particles with close momenta, the angular correlations between the directions of emission of decay products are considered on the basis of the model of independent single-particle sources emitting unstable unpolarized particles of nonzero spin. These correlations reflect spin correlations that are caused by quantum-statistics and final-state-interaction effects. A general theory of angular correlations in the decays of two arbitrarily polarized particles (resonances) is constructed. [ABSTRACT FROM AUTHOR]

The project NICA (Nuclotron-based Ion Collider fAcility) is aimed to study hot and baryon rich QCD matter in heavy ion collisions in the energy range up to s NN = 11 GeV . The heavy ion program includes a study of collective phenomena, dilepton, hyperon and hypernuclei production under extreme conditions of highest baryonic density. This program will be performed at a fixed target experiment BM@N and with MPD detector at the NICA collider. [ABSTRACT FROM AUTHOR]

The NICA (Nuclotron-based Ion Collider fAcility) project is under realization at the Joint Institute for Nuclear Research (JINR, Dubna). The main goal of the project is a study of hot and dense strongly interacting matter in heavy ion collisions (up to Au) in the energy range up to s N N = 11 GeV . Two modes of operation are foreseen, collider and extracted beam operations, with two detectors: MPD and BM@N. In the Au + Au collider mode the expected average luminosity is L = 10 27 cm − 2 s − 1 . The proposed experimental program allows one to search for possible manifestations of the phase transitions and critical phenomena. [ABSTRACT FROM AUTHOR]

Presents a corrected reprint of an article on nuclear physics published in a 2004 issue of "Physics of Atomic Nuclei".

Provides a corrected version of the article 'Final-State Interaction in Multichannel Quantum Systems and Pair Correlations of Nonidentical and Identical Particles at Low Relative Velocities,' by R. Lednicky et al published in the 1998 issue of the periodical 'Physics of Atomic Nuclei.'

The source radii previously extracted by the STAR Collaboration from the p -- Λ ⊕ ¯p -- ¯Λ and ¯p -- Λ ⊕ p -- ¯Λ correlation functions measured in 10% most central Au+Au collisions at top Relativistic Heavy Ion Collider (RHIC) energy, √sNN = 200 GeV, differ by a factor of 2. The probable reason for this is the neglect of residual correlation effect in the STAR analysis. In the present paper we analyze baryon correlation functions within the Lednický and Lyuboshitz analytical model, extended to effectively account for the residual correlation contribution. Different analytical approximations for such a contribution are considered. We also use the averaged source radii extracted from hydrokinetic model (HKM) simulations to fit the experimental data. In contrast to the STAR experimental study, the calculations in HKM show both pΛ and p¯Λ radii to be quite close, as expected from theoretical considerations. Using the effective Gaussian parametrization of residual correlations we obtain a satisfactory fit to the measured baryon-antibaryon correlation function with the HKM source radius value 3.28 fm. The baryon-antibaryon spin-averaged strong interaction scattering length is also extracted from the fit to the experimental correlation function. [ABSTRACT FROM AUTHOR]

Correlation femtoscopy allows one to measure the space-time characteristics of particle production in relativistic heavy-ion collisions due to the effects of quantum statistics (QS) and final state interactions (FSIs). The main features of the femtoscopy measurements at top RHIC and LHC energies are considered as a manifestation of strong collective flow and are well interpreted within hydrodynamic models employing equation of state (EoS) with a crossover type transition between quark-gluon plasma (QGP) and hadron gas phases. The femtoscopy at lower energies was intensively studied at AGS and SPS accelerators and is being studied now in the Beam Energy Scan program (BES) at the BNL Relativistic Heavy Ion Collider in the context of exploration of the QCD phase diagram. In this article we present femtoscopic observables calculated for Au-Au collisions at √sNN=7.7-62.4 GeV in a viscous hydro + cascade model vHLLE+UrQMD and their dependence on the EoS of thermalized matter. [ABSTRACT FROM AUTHOR]

We report preliminary data on proton-lambda correlations at small relative momentum q in the e3He(4He) → e′ pΛ X reaction at E0 = 4.7(4.46) GeV using the CLAS detector at Jefferson Lab. The enhancement of the correlation function at small q was found to be in qualitative agreement with theoretical expectations. The size of emission region about 1.5 fm was estimated using Lednický-Lyuboshitz analytical model. The experimental correlation function is comparable with the P-matrix fit of the hyperon-nucleon data. Small-relative-momentum-proton-lambda correlations both for 3He(4He) target and for electroproduction reaction were studied for the first time. [ABSTRACT FROM AUTHOR]

We report preliminary data on proton-lambda correlations at small relative momentum q in the e3He(4He) → e′ pΛX reaction at E0=4.7(4.46)GeV using the CLAS detector at Jefferson Lab. The enhancement of the correlation function at small q was found to be in qualitative agreement with theoretical expectations. The size of emission region about 1.5 fm was estimated using Lednický-Lyuboshitz analytical model. The experimental correlation function is compatible with the P-matrix fit of the hyperon-nucleon data. Small relative momentum proton-lambda correlations both for He target and for electroproduction reaction were studied for the first time. [ABSTRACT FROM AUTHOR]

The measurement of the two-particle correlation function for different particle species allows to obtain information about the development of the particle emission process: the space-time properties of emitting sources and the emission time sequence of different particles. The single-particle characteristics and two-particle correlation functions for neutral and charged particles registered in forward direction are used to determine that the heavy fragments (deuterons and tritons) are emitted in the first stage of the reaction (pre-equilibrium source) while the majority of neutrons and protons originates from the long-lived quasi-projectile. The emission time sequence of protons, neutrons and deuterons has been obtained from the analysis of non-identical particle correlation functions. [ABSTRACT FROM AUTHOR]

Results of the experimental study of p4He, d3He, dT, pT, p3He and, for the first time, nT, n3He, n4He correlations in the region of small relative momenta are presented. The data analysis provides an estimate of the effective source size or emission time. [ABSTRACT FROM AUTHOR]