Ultrarelativistic heavy ions

International Nuclear Information System (INIS)

Pugh, H.G.

1980-12-01

Studies with ultrarelativistic heavy ions combine aspects of cosmic ray physics, particle physics, nuclear physics, astrophysics and cosmogenesis. The leading theoretical concerns are the behavior of matter at very high-energy density and flux, the general behavior of space time in collisions, relativistic nuclear theory, and quantum chromodynamics. The field has developed over a period of more than thirty years, since the first observation of heavy nuclei in cosmic rays and the major developments of understanding of high-energy collisions made by Fermi and Landau in the early fifties. In the late sixties the discovery of the parton content of nucleons was rapidly followed by a great extension of high-energy collision phenomenology at the CERN ISR and subsequent confirmation of the QCD theory. In parallel the study of p-nucleus and nucleus-nucleus collisions at very high energies, especially at the CERN PS, Fermilab and the Bevalac, and in cosmic rays demonstrated that studies involving the nucleus opened up a new dimension in studies of the hadronic interaction. It is now at a high level of interest on an international scale, with major new accelerators being proposed to dedicate to this kind of study

CSR Impedance for Non-Ultrarelativistic Beams

International Nuclear Information System (INIS)

Li, Rui; Tsai, Cheng Y.

2015-09-01

For the analysis of the coherent synchrotron radiation (CSR)-induced microbunching gain in the low energy regime, such as when a high-brightness electron beam is transported through a low-energy merger in an energy-recovery linac (ERL) design, it is necessary to extend the CSR impedance expression in the ultrarelativistic limit to the non-ultrarelativistic regime. This paper presents our analysis of CSR impedance for general beam energies.

Ultrarelativistic atomic collisions

International Nuclear Information System (INIS)

Bottcher, C.; Strayer, M.R.

1991-01-01

Calculations of the coherent production of free pairs and of pair production with electron capture from ultrarelativistic ion-ion collisions are discussed. Theory and experiment are contrasted, with some conjectures on the possibility of new phenomena. 29 refs., 5 figs., 1 tab

Ultra-relativistic heavy ion collisions in a multi-string model

International Nuclear Information System (INIS)

Werner, K.

1987-01-01

We present a model for ultra-relativistic heavy ion collisions based on color string formation and subsequent independent string fragmentation. Strings are formed due to color exchange between quarks at each individual nucleon nucleon collision. The fragmentation is treated as in e + e - or lepton nucleon scattering. Calculation for pp, pA, and AA were carried out using the Monte Carlo code VENUS for Very Energetic Nuclear Scattering (version 1.0). 20 refs., 6 figs

Ultrarelativistic oscillon collisions

NARCIS (Netherlands)

Amin, M.A.; Banik, I.; Negreanu, C.; Yang, I.S.

2014-01-01

In this short paper we investigate the ultrarelativistic collisions of small amplitude oscillons in 1+1 dimensions. Using the amplitude of the oscillons and the inverse relativistic boost factor γ−1 as the perturbation variables, we analytically calculate the leading order spatial and temporal phase

On the time delay between ultra-relativistic particles

Energy Technology Data Exchange (ETDEWEB)

Fleury, Pierre, E-mail: pierre.fleury@uct.ac.za [Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch 7701, Cape Town (South Africa); Department of Physics, University of the Western Cape, Robert Sobukwe Road, Bellville 7535 (South Africa)

2016-09-10

The time delay between the receptions of ultra-relativistic particles emitted simultaneously is a useful observable for both fundamental physics and cosmology. The expression of the delay when the particles travel through an arbitrary spacetime has been derived recently by Fanizza et al., using a particular coordinate system and self-consistent assumptions. The present article shows that this formula enjoys a simple physical interpretation: the relative velocity between two ultra-relativistic particles is constant. This result reveals an interesting kinematical property of general relativity, namely that the tidal forces experienced by ultra-relativistic particles in the direction of their motion are much smaller than those experienced orthogonally to their motion.

On the time delay between ultra-relativistic particles

International Nuclear Information System (INIS)

Fleury, Pierre

2016-01-01

The time delay between the receptions of ultra-relativistic particles emitted simultaneously is a useful observable for both fundamental physics and cosmology. The expression of the delay when the particles travel through an arbitrary spacetime has been derived recently by Fanizza et al., using a particular coordinate system and self-consistent assumptions. The present article shows that this formula enjoys a simple physical interpretation: the relative velocity between two ultra-relativistic particles is constant. This result reveals an interesting kinematical property of general relativity, namely that the tidal forces experienced by ultra-relativistic particles in the direction of their motion are much smaller than those experienced orthogonally to their motion.

Inclusive jet production in ultrarelativistic proton-nucleus collisions

CERN Document Server

Perepelitsa, Dennis

High-$p_\\mathrm{T}$ processes in proton- and deuteron-nucleus collisions at TeV energies are the best presently available way to study the partonic structure of the nucleus in a high-density regime. Jet production over a wide range of phase space can significantly constrain the current knowledge of nuclear parton distribution functions (nPDFs), which are substantially less well understood than the corresponding PDFs in protons and which have only recently begun to be treated in a spatially-dependent way. An accurate knowledge of nPDFs is crucial for a definitive control of perturbative processes in a cold nuclear environment, since high-$p_\\mathrm{T}$ probes are used to quantitatively investigate the hot QCD matter created in ultrarelativistic nucleus-nucleus collisions. Furthermore, jets from low Bjorken-$x$ partons can probe the transition from the dilute to saturated nuclear regimes. Jet production is investigated in $d$+Au collisions at $\\sqrt{s} = 200$ GeV with the PHENIX detector at the Relativistic Hea...

Entrance and Exit CSR Impedance for Non-Ultrarelativistic Beam

Energy Technology Data Exchange (ETDEWEB)

Li, Rui; Tsai, Cheng Ying [SLAC National Accelerator Lab., Menlo Park, CA (United States); Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)

2017-05-01

For a high-brightness electron beam being transported through beamlines involving bending systems, the coherent synchrotron radiation (CSR) and longitudinal space charge (LSC) interaction could often cause microbunching instability. The semi-analytical Vlasov solver for microbunching gain* depends on the impedances for the relevant collective effects. The existing results for CSR impedances are usually obtained for the ultrarelativistic limit. To extend the microbunching analysis to cases of low energies, such as the case of an ERL merger, or to density modulations at extremely small wavelength, it is necessary to extend the impedance analysis to the non-ultrarelativistic regime. In this study, we present the impedance analysis for the transient CSR interaction in the non-ultrarelativistic regime, for transients including both entrance to and exit from a magnetic dipole. These impedance results will be compared to their ultra-relativistic counterparts**, and the corresponding wakefield obtained from the impedance for low-energy beams will be compared with the existing results of transient CSR wakefield for general beam energies***.

Ultra-relativistic heavy-ion physics with AFTER@LHC

DEFF Research Database (Denmark)

Rakotozafindrabe, A.; Arnaldi, R.; Brodsky, Stanley

2013-01-01

We outline the opportunities for ultra-relativistic heavy–ion physics which are offered by a next generation and multi-purpose fixed-target experiment exploiting the proton and ion LHC beams extracted by a bent crystal.......We outline the opportunities for ultra-relativistic heavy–ion physics which are offered by a next generation and multi-purpose fixed-target experiment exploiting the proton and ion LHC beams extracted by a bent crystal....

Physics of Ultrarelativistic Heavy Ions

International Nuclear Information System (INIS)

Giubellino, P.

1996-01-01

This paper is devoted to a general presentation of the physics of Ultrarelativistic Heavy Ions, as seen from the experimentalist close-quote s point of view. The aim of this research is the study of nuclear matter under extreme conditions of temperature and pressure, extending in this way our understanding of the strong interactions in general, and of colour confinement in particular. This young field of Physics has been growing rapidly in the past years, and any attempt to cover it in few pages will be rather sketchy and many important aspects will have to be left out. I will mainly try to cover the general motivations to undertake this study, and just mention the experimental challenges to be faced, the results from the experiments at CERN and BNL, and finally the fascinating program ahead of us, with a glimpse at the CERN LHC used as a heavy-ion collider. copyright 1996 American Institute of Physics

Effect of phase transition on QGP fluid in ultra-relativistic heavy ion collision

International Nuclear Information System (INIS)

Nonaka, Chiho; Miyamura, Osamu; Muroya, Shin

2001-01-01

A full (3+1)-dimensional calculation using the Lagrangian hydrodynamics is proposed for relativistic nuclear collisions. The calculation enables us to evaluate anisotropic flow of hot and dense matter which appears in non-central and/or asymmetrical relativistic nuclear collisions. The relativistic hydrodynamical model is related to the equation of the state and the useful for the verification of quark-gluon plasma state. By virtue of the Lagrangian hydrodynamics we can easily trace the trajectory which corresponds to the adiabatic paths in the T-μ plane. We evaluate the directly of the influence of the phase transition to physical phenomena in the ultra-relativistic nuclear collisions. Using our relativistic hydrodynamical model, we discuss the effect of the phase transition on the collective flow. (author)

ULTRA-RELATIVISTIC NUCLEI: A NEW FRONTIER

International Nuclear Information System (INIS)

MCLERRAN, L.

1999-01-01

The collisions of ultra-relativistic nuclei provide a window on the behavior of strong interactions at asymptotically high energies. They also will allow the authors to study the bulk properties of hadronic matter at very high densities

Hydrodynamics of ultra-relativistic bubble walls

Energy Technology Data Exchange (ETDEWEB)

Leitao, Leonardo, E-mail: lleitao@mdp.edu.ar; Mégevand, Ariel, E-mail: megevand@mdp.edu.ar

2016-04-15

In cosmological first-order phase transitions, gravitational waves are generated by the collisions of bubble walls and by the bulk motions caused in the fluid. A sizeable signal may result from fast-moving walls. In this work we study the hydrodynamics associated to the fastest propagation modes, namely, ultra-relativistic detonations and runaway solutions. We compute the energy injected by the phase transition into the fluid and the energy which accumulates in the bubble walls. We provide analytic approximations and fits as functions of the net force acting on the wall, which can be readily evaluated for specific models. We also study the back-reaction of hydrodynamics on the wall motion, and we discuss the extrapolation of the friction force away from the ultra-relativistic limit. We use these results to estimate the gravitational wave signal from detonations and runaway walls.

Hydrodynamics of ultra-relativistic bubble walls

Directory of Open Access Journals (Sweden)

Leonardo Leitao

2016-04-01

Full Text Available In cosmological first-order phase transitions, gravitational waves are generated by the collisions of bubble walls and by the bulk motions caused in the fluid. A sizeable signal may result from fast-moving walls. In this work we study the hydrodynamics associated to the fastest propagation modes, namely, ultra-relativistic detonations and runaway solutions. We compute the energy injected by the phase transition into the fluid and the energy which accumulates in the bubble walls. We provide analytic approximations and fits as functions of the net force acting on the wall, which can be readily evaluated for specific models. We also study the back-reaction of hydrodynamics on the wall motion, and we discuss the extrapolation of the friction force away from the ultra-relativistic limit. We use these results to estimate the gravitational wave signal from detonations and runaway walls.

Ultrarelativistic heavy-ion collisions. Proceedings of the International Workshop XXX on Gross Properties of Nuclei and Nuclear Excitations

International Nuclear Information System (INIS)

Buballa, M.; Noerenberg, W.; Schaefer, B.J.; Wambach, J.

2002-01-01

The following topics were dealt with: Experimental results on ultrarelativistic heavy ion collisions, QCD thermodynamics, equilibration in relativistic heavy ion collisions, lattice QCD, space- time evolution and Hanbury-Brown-Twiss correlations, vector meson production, high-p T and small-x physics. (HSI)

Probing the specific entropy produced in ultra-relativistic heavy-ion collisions with a silicon pixel multiplicity detector: a simulation study

Czech Academy of Sciences Publication Activity Database

Antinori, F.; Balada, A.; Barbera, R.; Staroba, Pavel; Závada, Petr

2000-01-01

Roč. 452, - (2000), s. 323-337 ISSN 0168-9002 Institutional research plan: CEZ:AV0Z1010920 Keywords : ultra-relativistic * heavy-ion collisions * nuclear matter * phase diagram * hadron gas * Quark Gluon Plasma * particle multiplicity * transverse momentum spectra Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 0.964, year: 2000

In-medium Modifications of Hadron Masses and Chemical Freeze-out in Ultra-relativistic Heavy-ion Collisions

International Nuclear Information System (INIS)

Florkowski, W.; Broniowski, W.

1999-10-01

We confront the hypothesis of chemical freeze-out in ultra-relativistic heavy-ion collisions with the hypothesis of large modifications of hadron masses in nuclear medium. We find that the thermal-model predictions for the ratios of particle multiplicities are sensitive to the values of in-medium hadronic masses. In particular, the π + /p ratio decreases by 35% when the masses of all hadrons (except for pseudo-Goldstone bosons) are scaled down by 30%. (author)

$W$ boson production in ultrarelativistic heavy-ion collisions at the CERN LHC

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00356981

Ultrarelativistic heavy-ion collisions at the CERN Large Hadron Collider (LHC) are capable of producing a medium of deconfined quarks and gluons. This phase of nuclear matter is called a Quark-Gluon Plasma (QGP) and is believed to have been present during the first microseconds following the Big Bang. $\\Wboson$ bosons are a unique probe in a QGP since they do not carry color charge and thus do not interact with a strongly-coupled medium. Furthermore, the kinematics of $\\Wboson$ bosons are sensitive to the Bjorken momentum fraction $x$ of partons within nucleons, and therefore $\\Wboson$ bosons may also be used to constrain parton distribution functions and to detect the presence of nuclear effects. This thesis presents the measurement of $\\Wboson$ boson production in the dense nuclear environment created in $\\PbPb$ collisions at a per nucleon pair center-of-mass energy $\\sqrt{s_{\\mathrm{NN}}}=2.76\\TeV$. The data for this measurement were collected with the ATLAS detector in 2011 and correspond to a...

Ultrarelativistic heavy ion collisions Theoretical overview

International Nuclear Information System (INIS)

Blaizot, Jean-Paul

2006-01-01

This is a short review of some theoretical aspects of the physics of ultra-relativistic heavy ion collisions. I review the main properties of the QCD phase diagram and recent developments in the physics of high gluon densities in the hadronic wavefunctions at high energy. Then I comment salient results obtained at RHIC

Nuclear Science Division annual report for 1991

International Nuclear Information System (INIS)

Myers, W.D.

1992-04-01

This paper discusses research being conducted under the following programs: Low energy research program; bevalac research program; ultrarelativistic research program; nuclear theory program; nuclear theory program; nuclear data evaluation program; and 88-inch cyclotron operations

Plasma production and hadronization in ultrarelativistic nuclear collisions

International Nuclear Information System (INIS)

Kataja, M.

1990-01-01

We study the color confinement and hadronization in the thermodynamic limit of the flux tube model, which was recently developed to describe the energy deposition, particle production and the early expansion of plasma in the central region of ultrarelativistic heavy ion collisions. In this purpose, we introduce a concept of an intermediate 'mixed state', which is formed when the original giant flux tube is fragmented into many smaller tubes which contain the plasma and the Abelian color-electric field and which coexist with a dilute hadron gas. This mixed state is an extension of the mixed phase used in the pure hydrodynamic description utilizing the bag equation of state. We study the thermodynamics of this mixed state making use of the bag model and the classical models of color confinement. It appears that in the thermodynamic limit, the mixed state can be considered as a dielectric medium in which the color dielectric constant takes the values between 0 and 1. We also study how the 'equations of electrohydrodynamics', which were formulated in earlier works to describe the evolution of the giant flux tube and plasma, are to be modified due to the dielectric nature of the new transient mixed state. A numeric simulation of a one-dimensional scaling expansion demonstrates the dynamic transition of the system from plasma to hadron phase and the characteristic reheating effect due to this hadronization transition. It is also shown that in the limit of low temperature or large bag constant, this formalism is reduced to the hydrodynamics of hadron gas produced by the fragmentation of multiple strings. (orig.)

Uma atualidade in extremis: Foucault entre Marx e o neoliberalismo

Directory of Open Access Journals (Sweden)

Nilton Ken Ota

2017-12-01

Full Text Available A participação de Foucault no GIP marcou o momento de constituição de sua teoria estratégica das lutas no contexto de uma interlocução com militantes marxistas. O enfraquecimento dessa interlocução foi acompanhado pelo início das pesquisas genealógicas e por uma reformulação conceitual que dispersou o problema da racionalidade estratégica em benefício da construção de uma discursividade propriamente teórica. As controvérsias atuais ao redor dos sentidos do legado foucaultiano, cujo movimento pendular tem variado entre Marx e o neoliberalismo, revelam os efeitos de uma trajetória intelectual que se dividiu entre a reflexão crítica do combate concreto e a elaboração conceitual de um experimentalismo radical. Este artigo pretende reconstruir os principais pontos e conformações teóricas dessa trajetória. The participation of Foucault in GIP marked the moment of creation of strategic theory about the struggles in the context of a dialogue with Marxist militants. The weakening of that dialogue was accompanied by the start of genealogical research and, consequently, a conceptual reformulation which, among other changes, dispersed the problem of strategic rationality for the construction of a properly theoretical discursiveness. The current controversy surrounding the way the Foucault's legacy, whose pendulum has varied between Marx and neo-liberalism, reveal the effects of an intellectual journey that was divided between the critical reflection of the actual combat and the conceptual formulation of a radical experimentalism. The article An Actuality in extremis: Foucault Between Marx and Neoliberalism aims to reconstruct the main points and theoretical conformations that trajectory.Keywords: Marxism, strategy, neoliberalism, engagement, intellectuals

INFN what next ultra-relativistic heavy-ion collisions

CERN Document Server

Dainese, A.; Usai, G.; Antonioli, P.; Arnaldi, R.; Beraudo, A.; Bruna, E.; Bruno, G.E.; Bufalino, S.; Di Nezza, P.; Lombardo, M.P.; Nania, R.; Noferini, F.; Oppedisano, C.; Piano, S.; Prino, F.; Rossi, A.; Agnello, M.; Alberico, W.M.; Alessandro, B.; Alici, A.; Andronico, G.; Antinori, F.; Arcelli, S.; Badala, A.; Barbano, A.M.; Barbera, R.; Barile, F.; Basile, M.; Becattini, F.; Bedda, C.; Bellini, F.; Beole, S.; Bianchi, L.; Bianchin, C.; Bonati, C.; Bossu, F.; Botta, E.; Caffarri, D.; Camerini, P.; Carnesecchi, F.; Casula, E.; Cerello, P.; Cicalo, C.; Cifarelli, M.L.; Cindolo, F.; Colamaria, F.; Colella, D.; Colocci, M.; Corrales Morales, Y.; Cortese, P.; De Caro, A.; De Cataldo, G.; De Falco, A.; De Gruttola, D.; D'Elia, M.; De Marco, N.; De Pasquale, S.; Di Bari, D.; Elia, D.; Fantoni, A.; Feliciello, A.; Ferretti, A.; Festanti, A.; Fionda, F.; Fiorenza, G.; Fragiacomo, E.; Fronze, G.G.; Girard, M. Fusco; Gagliardi, M.; Gallio, M.; Garg, K.; Giubellino, P.; Greco, V.; Grossi, E.; Guerzoni, B.; Hatzifotiadou, D.; Incani, E.; Innocenti, G.M.; Jacazio, N.; Das, S. Kumar; La Rocca, P.; Lea, R.; Leardini, L.; Leoncino, M.; Lunardon, M.; Luparello, G.; Mantovani Sarti, V.; Manzari, V.; Marchisone, M.; Margagliotti, G.V.; Masera, M.; Masoni, A.; Mastroserio, A.; Mazzilli, M.; Mazzoni, M.A.; Meninno, E.; Mesiti, M.; Milano, L.; Moretto, S.; Muccifora, V.; Nappi, E.; Nardi, M.; Nicassio, M.; Pagano, P.; Pappalardo, G.S.; Pastore, C.; Paul, B.; Petta, C.; Pinazza, O.; Plumari, S.; Preghenella, R.; Puccio, M.; Puddu, G.; Ramello, L.; Ratti, C.; Ravasenga, I.; Riggi, F.; Ronchetti, F.; Rucci, A.; Ruggieri, M.; Rui, R.; Sakai, S.; Scapparone, E.; Scardina, F.; Scarlassara, F.; Scioli, G.; Siddhanta, S.; Sitta, M.; Soramel, F.; Suljic, M.; Terrevoli, C.; Trogolo, S.; Trombetta, G.; Turrisi, R.; Vercellin, E.; Vino, G.; Virgili, T.; Volpe, G.; Williams, M.C.S.; Zampolli, C.

2016-01-01

This document was prepared by the community that is active in Italy, within INFN (Istituto Nazionale di Fisica Nucleare), in the field of ultra-relativistic heavy-ion collisions. The experimental study of the phase diagram of strongly-interacting matter and of the Quark-Gluon Plasma (QGP) deconfined state will proceed, in the next 10-15 years, along two directions: the high-energy regime at RHIC and at the LHC, and the low-energy regime at FAIR, NICA, SPS and RHIC. The Italian community is strongly involved in the present and future programme of the ALICE experiment, the upgrade of which will open, in the 2020s, a new phase of high-precision characterisation of the QGP properties at the LHC. As a complement of this main activity, there is a growing interest in a possible future experiment at the SPS, which would target the search for the onset of deconfinement using dimuon measurements. On a longer timescale, the community looks with interest at the ongoing studies and discussions on a possible fixed-target p...

Deconfinement transition and collisions of ultrarelativistic heavy ions

International Nuclear Information System (INIS)

Ollitrault, J.Y.

1989-01-01

The quark-gluon plasma is a new phase of nuclear matter which one hopes to produce in collisions of ultrarelativistic nuclei. In this thesis, we study some of the possible signatures which have been proposed to identify the plasma in these experiments. The first chapter of this thesis is devoted to the study of a hydrodynamical model describing these collisions: we solve numerically the equations of hydrodynamics; this allows us to compute the measured particle distributions, and to characterize the effect of a phase transition on the average transverse momentum of the emitted pions. The second chapter is a theoretical study of J/Ψ suppression, which has been suggested as a signal for quark-gluon plasma formation, and then observed by NA38 collaboration at CERN. We discuss the possible interpretations of this effect by comparing several models: the first model is based on the hypothesis of plasma formation while in the others, the suppression comes from inelastic scattering of the J/Ψ with the nuclei or with the particles produced in the collision [fr

Search for free quarks produced in ultra-relativistic collisions at BNL [Brookhaven National Laboratory] and CERN [European Organization for Nuclear Research

International Nuclear Information System (INIS)

Matis, H.S.; Pugh, H.G.; Alba, G.P.; Bland, R.W.; Calloway, D.H.; Dickson, S.; Hodges, C.L.; Palmer, T.L.; Stricker, D.A.; Johnson, R.T.

1990-07-01

A high intensity experiment was performed to search for free quarks at BNL and CERN using ultra-relativistic beams. The experiment was designed to trap quarks in a Hg target or liquid Ar tank. No free quark candidate was found. Limits from 10 -7 to 10 -10 quarks per incident ion are reported. 7 refs., 2 figs., 2 tabs

Elliptic flow and energy loss of heavy quarks in ultrarelativistic heavy ion collisions

International Nuclear Information System (INIS)

Uphoff, Jan; Fochler, Oliver; Greiner, Carsten; Xu, Zhe

2011-01-01

The space-time propagation of heavy quarks in ultrarelativistic heavy ion collisions is studied within the partonic transport model Boltzmann approach of multiparton scatterings (BAMPS). In this model heavy quarks interact with the partonic medium via binary scatterings. The cross sections for these interactions are calculated with leading-order perturbative QCD, but feature a more precise Debye screening derived within the hard thermal loop approximation and obey the running of the coupling. Within this framework the elliptic flow and the nuclear modification factor of heavy quarks are computed for the BNL Relativistic Heavy Ion Collider (RHIC) and the CERN Large Hadron Collider (LHC) energies and compared to available experimental data. It is found that binary scatterings alone cannot reproduce the data and therefore radiative corrections have to be taken into account.

Gross properties of nuclei and nuclear excitations

International Nuclear Information System (INIS)

Feldmeier, H.

1986-01-01

These proceedings contain the invited and contributed papers presented at the named workshop. They deal with special topics in high- and intermediate-energy nuclear physics. Especially considered are the quark-gluon plasma, ultrarelativistic heavy ion reactions, and the application of QCD to nuclear structure calculations. (HSI)

Nuclear Science Division, Annual report, October 1, 1988--December 31, 1990

Energy Technology Data Exchange (ETDEWEB)

Poskanzer, A.M.; Deleplanque, M.A.; Firestone, R.B.; Lofdahl, J.B. (eds.)

1991-04-01

This report contains short papers of research conducted in the following areas: Low energy research program; bevalac research program; ultrarelativistic research program; nuclear theory program; nuclear data evaluation; and, 88-inch cyclotron operations.

Nuclear Science Division, Annual report, October 1, 1988--December 31, 1990

International Nuclear Information System (INIS)

Poskanzer, A.M.; Deleplanque, M.A.; Firestone, R.B.; Lofdahl, J.B.

1991-04-01

This report contains short papers of research conducted in the following areas: Low energy research program; bevalac research program; ultrarelativistic research program; nuclear theory program; nuclear data evaluation; and, 88-inch cyclotron operations

Elastic and radiative heavy quark interactions in ultra-relativistic heavy-ion collisions

International Nuclear Information System (INIS)

Uphoff, Jan; Fochler, Oliver; Xu, Zhe; Greiner, Carsten

2015-01-01

Elastic and radiative heavy quark interactions with light partons are studied with the partonic transport model named the Boltzmann approach to multiparton scatterings (BAMPSs). After calculating the cross section of radiative processes for finite masses in the improved Gunion–Bertsch approximation and verifying this calculation by comparing to the exact result, we study elastic and radiative heavy quark energy loss in a static medium of quarks and gluons. Furthermore, the full 3 + 1D space–time evolution of gluons, light quarks, and heavy quarks in ultra-relativistic heavy-ion collisions at the BNL Relativistic Heavy-Ion Collider (RHIC) and the CERN Large Hadron Collider (LHC) are calculated with BAMPS including elastic and radiative heavy flavor interactions. Treating light and heavy particles on the same footing in the same framework, we find that the experimentally measured nuclear modification factor of charged hadrons and D mesons at the LHC can be simultaneously described. In addition, we calculate the heavy flavor evolution with an improved screening procedure from hard-thermal-loop calculations and confront the results with experimental data of the nuclear modification factor and the elliptic flow of heavy flavor particles at the RHIC and the LHC. (paper)

On the ultrarelativistic limit of general relativity

International Nuclear Information System (INIS)

Dautcourt, G.

1998-01-01

As is well-known, Newton's gravitational theory can be formulated as a four-dimensional space-time theory and follows as singular limit from Einstein's theory, if the velocity of light tends to the infinity. Here 'singular' stands for the fact, that the limiting geometrical structure differs from a regular Riemannian space-time. Geometrically, the transition Einstein → Newton can be viewed as an 'opening' of the light cones. This picture suggests that there might be other singular limits of Einstein's theory: Let all light cones shrink and ultimately become part of a congruence of singular world lines. The limiting structure may be considered as a null hypersurface embedded in a five-dimensional spacetime. While the velocity of light tends to zero here, all other velocities tend to the velocity of light. Thus one may speak of an ultrarelativistic limit of General Relativity. The resulting theory is as simple as Newton's gravitational theory, with the basic difference, that Newton's elliptic differential equation is replaced by essentially ordinary differential equations, with derivatives tangent to the generators of the singular congruence. The Galilei group is replaced by the Carroll group introduced by Levy-Leblond. We suggest to study near ultrarelativistic situations with a perturbational approach starting from the singular structure, similar to post-Newtonian expansions in the c → ∞ case. (author)

Pion interferometry of ultra-relativistic hadronic collisions

International Nuclear Information System (INIS)

Kolehmainen, K.

1986-05-01

Pion interferometry of ultra-relativistic hadronic collisions is described in the context of the inside-outside cascade model using a current ensemble method capable of describing an arbitrary distribution of pion sources with an arbitrary velocity distribution. The results are quite distinct from the usual Gaussian and Kopylov parameterizations. Extraction of the temperature parameter, effective source lifetime, and transverse size requires a full three-dimensional analysis of the correlation function in terms of the momentum difference. 7 refs., 4 figs

Charm and strangeness of ultrarelativistic heavy ion collisions

International Nuclear Information System (INIS)

Gerschel, C.

1994-01-01

Charmonium and strangeness production in collisions induced by ultrarelativistic sulfur or silicon ions is reviewed. A suppression of charmonium production and a strangeness enhancement are observed. Predicted as potential signatures of the quark gluon plasma formation, their interpretation is still very much debated. The status of the discussion will be given as well as the expected evolutions with the forthcoming Pb beams. (author). 45 refs., 11 figs., 1 tab

Two views on the Bjorken scenario for ultra-relativistic heavy-ion collisions

CERN Multimedia

Maire, Antonin

2011-01-01

The sketch describes the Bjorken scenario foreseen for the collision of ultra-relativistic heavy-ions, leading to the creation of strongly-interacting hot and dense deconfined matter, the so-called Quark-Gluon Plasma (QGP).

Electron loss from heavy heliumlike projectiles in ultrarelativistic collisions with many-electron atomic targets

International Nuclear Information System (INIS)

Mueller, C.; Gruen, N.; Voitkiv, A.B.

2002-01-01

We study single- and double-electron loss from heavy heliumlike projectiles in ultrarelativistic collisions with neutral many-electron target atoms. The simultaneous interaction of the target with two projectile electrons is found to be the dominant process in the double-electron loss provided the atomic number of the projectile, Z p , that of the target, Z t , and the collision velocity, v, satisfy the condition Z p Z t /v>0.4. It is shown that for a wide range of projectile and target atomic numbers the asymptotic double-to-single loss ratio strongly depends on the target atomic number but is nearly independent of the nuclear charge of the projectile. It is also demonstrated that many-photon exchange between the target and each of the projectile electrons considerably influences the double loss in collisions with very heavy targets

Interaction of ultrarelativistic electron and proton bunches with dense plasmas

CERN Document Server

Rukhadze, A A

2012-01-01

Here we discuss the possibility of employment of ultrarelativistic electron and proton bunches for generation of high plasma wakefields in dense plasmas due to the Cherenkov resonance plasma-bunch interaction. We estimate the maximum amplitude of such a wake and minimum system length at which the maximum amplitude can be generated at the given bunch parameters.

The multistring model VENUS for ultrarelativistic heavy ion collisions

International Nuclear Information System (INIS)

Werner, K.

1988-02-01

The event generator VENUS is based on a multistring model for heavy ion collisions at ultrarelativistic energies. The model is a straightforward extension of a successful model for soft proton-proton scattering, the latter one being consistent with e/sup /plus//e/sup /minus// annihilation and deep inelastic lepton scattering. Comparisons of VENUS results with pA and recent AA data alow some statements about intranuclear cascading. 18 refs., 7 figs

Simulation of soft hadron hadron collisions at ultrarelativistic energies

International Nuclear Information System (INIS)

Werner, K.

1987-01-01

An event generator to simulate ultrarelativistic hadron hadron collisions is proposed. It is based on the following main assumptions: the process can be divided into two independent steps, string formation and string fragmentation; strings are formed as a consequence of color exchange between a quark of the projectile and a quark of the target; the fragmentation of strings is the same as in e + e - annihilation or in lepton nucleon scattering. 11 refs., 4 figs

High energy cosmic ray events of ultra-relativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Burnett, T.H.; Dake, S.; Derricson, J.H.; Fountain, W.; Fuki, M.; Gregory, J.C.; Hayashi, T.; Hayashi, T.; Holynski, R.; Iwai, J.; Jones, W.V.; Jurak, A.; Lord, J.J.; Meegan, C.A.; Miyamura, O.; Oda, H.; Ogata, T.; Parnell, T.A.; Roberts, E.; Saito, T.; Strauss, S.; Tabuki, T.; Takahashi, Y.; Tominaga, T.; Watts, J.W.; Wilczynska, B.; Wilkes, R.J.; Wolter, W.; Bosiek, B.

1985-01-01

Japanese American Cooperative Emulsion Experiment (JACEE) has been measuring ultrarelativistic comic ray nucleus and sampling the events in the energy regions both 10 to 100 GeV/A and above TeV/A by balloon emulsion chamber since 1979. In this report main results obtained up to now will be described. (orig./HSI)

Activities report 1991-1992: Nuclear Research Center of Strasbourg

International Nuclear Information System (INIS)

1993-01-01

This activities report of the Nuclear Research Centre of Strasbourg for the years 1991 and 1992, presents nine research axis: theoretical physics, mechanisms of reactions and nuclear structure, extreme forms of nuclei, exotic nuclei, hot and dense nuclear matter, ultra-relativistic heavy ions, physics of LEP (European Large Electron-Positron storage ring) at 'DELPHI', chemistry and physics of radiations, physics and applications of semi-conductors

Heavy quarks thermalization in heavy-ion ultrarelativistic collisions: elastic or radiative?

International Nuclear Information System (INIS)

Gossiaux, Pol Bernard; Guiho, Vincent; Aichelin, Joerg

2006-01-01

We present a dynamical model of heavy quark evolution in the quark-gluon plasma (QGP) based on the Fokker-Planck equation. We then apply this model to the case of ultrarelativistic nucleus-nucleus collisions performed at RHIC in order to investigate which experimental observables might help to discriminate the fundamental process leading to thermalization

Phase transition dynamics in ultrarelativistic heavy ion collisions

International Nuclear Information System (INIS)

Csernai, L.P.; Zabrodin, E.E.; Moscow State Univ.

1993-01-01

We investigate various problems related to the dynamics of a first-order phase transition from quarkgluon plasma to hadronic matter in ultra-relativistic heavy ion collisions. These include nucleation, growth and fusion of hadronic bubbles in either the Bjorken longitudinal hydrodynamic expansion model or the Cooper-Frye-Schonberg spherical hydrodynamic expansion model. With reasonable input parameters the conversion of one phase into the other is relatively close to the idealized adiabatic Maxwell construction, although one can choose parameters such that the conversion is strongly out of equilibrium. (orig.)

Phase transition dynamics in ultrarelativistic heavy ion collisions

International Nuclear Information System (INIS)

Csernai, L.P.; Kapusta, J.I.; Kluge, Gy.; Hungarian Academy of Sciences, Budapest; Zabrodin, E.E.; Moskovskij Gosudarstvennyj Univ., Moscow

1992-12-01

Various problems were investigated concerning the dynamics of a first-order phase transition from quark-gluon plasma to hadronic matter in ultra-relativistic heavy ion collisions. These include nucleation, growth and fusion of hadronic bubbles in either the Bjorken longitudinal hydrodynamic expansion model or the Cooper-Frye-Schonberg spherical hydrodynamic expansion model. With reasonable input parameters the conversion of one phase into the other is relatively close to the idealized adiabatic Maxwell construction, although one can choose parameters such that the conversion is strongly out of equilibrium. (author) 10 refs.; 7 figs

Overview of electromagnetic probe production in ultra-relativistic heavy ion collisions

International Nuclear Information System (INIS)

Paquet, Jean-François

2017-01-01

An introductory overview of electromagnetic probe production in ultra-relativistic heavy ion collisions is provided. Experimental evidence supporting the production of thermal photons and dileptons in heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) are reviewed. Thermal electromagnetic probe production from hydrodynamical models of collisions is discussed. (paper)

Ultra-relativistic ion acceleration in the laser-plasma interactions

Energy Technology Data Exchange (ETDEWEB)

Huang Yongsheng; Wang Naiyan; Tang Xiuzhang; Shi Yijin [China Institute of Atomic Energy, Beijing 102413 (China); Xueqing Yan [Institute of Heavy Ion Physics, Peking University, Beijing 100871 (China)

2012-09-15

An analytical relativistic model is proposed to describe the relativistic ion acceleration in the interaction of ultra-intense laser pulses with thin-foil plasmas. It is found that there is a critical value of the ion momentum to make sure that the ions are trapped by the light sail and accelerated in the radiation pressure acceleration (RPA) region. If the initial ion momentum is smaller than the critical value, that is in the classical case of RPA, the potential has a deep well and traps the ions to be accelerated, as the same described before by simulation results [Eliasson et al., New J. Phys. 11, 073006 (2009)]. There is a new ion acceleration region different from RPA, called ultra-relativistic acceleration, if the ion momentum exceeds the critical value. In this case, ions will experience a potential downhill. The dependence of the ion momentum and the self-similar variable at the ion front on the acceleration time has been obtained. In the ultra-relativistic limit, the ion momentum at the ion front is proportional to t{sup 4/5}, where t is the acceleration time. In our analytical hydrodynamical model, it is naturally predicted that the ion distribution from RPA is not monoenergetic, although the phase-stable acceleration mechanism is effective. The critical conditions of the laser and plasma parameters which identify the two acceleration modes have been achieved.

Ultra-relativistic ion acceleration in the laser-plasma interactions

International Nuclear Information System (INIS)

Huang Yongsheng; Wang Naiyan; Tang Xiuzhang; Shi Yijin; Xueqing Yan

2012-01-01

An analytical relativistic model is proposed to describe the relativistic ion acceleration in the interaction of ultra-intense laser pulses with thin-foil plasmas. It is found that there is a critical value of the ion momentum to make sure that the ions are trapped by the light sail and accelerated in the radiation pressure acceleration (RPA) region. If the initial ion momentum is smaller than the critical value, that is in the classical case of RPA, the potential has a deep well and traps the ions to be accelerated, as the same described before by simulation results [Eliasson et al., New J. Phys. 11, 073006 (2009)]. There is a new ion acceleration region different from RPA, called ultra-relativistic acceleration, if the ion momentum exceeds the critical value. In this case, ions will experience a potential downhill. The dependence of the ion momentum and the self-similar variable at the ion front on the acceleration time has been obtained. In the ultra-relativistic limit, the ion momentum at the ion front is proportional to t 4/5 , where t is the acceleration time. In our analytical hydrodynamical model, it is naturally predicted that the ion distribution from RPA is not monoenergetic, although the phase-stable acceleration mechanism is effective. The critical conditions of the laser and plasma parameters which identify the two acceleration modes have been achieved.

Measurements of the spectral location of the structured target resonance for ultrarelativistic electrons

NARCIS (Netherlands)

Andersen, K.; Ketel, T.J.

2014-01-01

When an ultrarelativistic electron traverses two closely spaced foils, a radiation spectrum 'resonance' appears, arising from the photon formation length extending from one foil, across the gap and into the second foil. Several theoretical approaches yield quite different answers to the spectral

Correlations of neutral pions in ultrarelativistic heavy ion collisions

International Nuclear Information System (INIS)

Peitzmann, T.; Beckmann, P.; Berger, F.; Glewing, G.; Dragon, L.; Glasow, R.; Kampert, K.H.; Loehner, H.; Purschke, M.; Santo, R.; Albrecht, R.; Bock, R.; Claesson, G.; Gutbrod, H.H.; Kolb, B.W.; Lund, I.; Schmidt, H.R.; Siemiarczuk, T.; Awes, T.C.; Baktash, C.; Ferguson, R.L.; Lee, I.Y.; Obenshain, F.E.; Plasil, F.; Soerensen, S.P.; Young, G.R.; Eklund, A.; Garpman, S.; Gustafsson, H.A.; Idh, J.; Kristiansson, P.; Oskarsson, A.; Otterlund, I.; Persson, S.; Stenlund, E.; Franz, A.; Poskanzer, A.M.; Ritter, H.G.

1989-01-01

Correlations of 4 photons representing neutral pions have been studied in ultrarelativistic heavy ion collisions. Data were taken in the WA80 experiment at the CERN-SPS with a 200 A GeV oxygen beam. The π 0 are detected via their decay photons with a high-granularity lead glass array. Special features of interferometry using neutral pions will be discussed. The extracted preliminary parameters for high p T pions emitted near midrapidity in O+Au collisions lead to rather small effective source sizes. (orig.)

Nuclear spectroscopic studies

Energy Technology Data Exchange (ETDEWEB)

Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

1993-02-08

The Nuclear Physics group at the University of Tennessee, Knoxville is involved in several aspects of heavy-ion physics including both nuclear structure and reaction mechanisms. While our main emphasis is on experimental problems involving heavy-ion accelerators, we have maintained a strong collaboration with several theorists in order to best pursue the physics of our measurements. During the last year we have led several experiments at the Holifield Heavy Ion Research Facility and participated in others at Argonne National Laboratory. Also, we continue to be very active in the collaboration to study ultra-relativistic heavy ion physics utilizing the SPS accelerator at CERN in Geneva, Switzerland and in a RHIC detector R D project. Our experimental work is in four broad areas: (1) the structure of nuclei at high angular momentum, (2) heavy-ion induced transfer reactions, (3) the structure of nuclei far from stability, and (4) ultra-relativistic heavy-ion physics. The results of studies in these particular areas will be described in this document in sections IIA, IIB, IIC, and IID, respectively. Areas (1), (3), and (4) concentrate on the structure of nuclear matter in extreme conditions of rotational motion, imbalance of neutrons and protons, or very high temperature and density. Area (2) pursues the transfer of nucleons to states with high angular momentum, both to learn about their structure and to understand the transfer of particles, energy, and angular momentum in collisions between heavy ions. An important component of our program is the strong emphasis on the theoretical aspects of nuclear structure and reactions.

Nuclear spectroscopic studies

International Nuclear Information System (INIS)

Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

1991-01-01

The Nuclear Physics group at the University of Tennessee, Knoxville is involved in several aspects of heavy-ion physics including both nuclear structure and reaction mechanisms. While our main emphasis is on experimental problems involving heavy-ion accelerators, we have maintained a strong collaboration with several theorists in order to best pursue the physics of our measurements. During the last year we have led experiments at the Holifield Heavy Ion Research Facility, the SuperHILAC at Berkeley, and Chalk River Tandem Accelerator. Also, we have joined a collaboration to study ultra-relativistic heavy ion physics and one of our group has spent all of 1987 at CERN to work on the WA80 experiment. Our experimental work is in four broad areas: (1) the structure of nuclei at high angular momentum, (2) heavy-ion induced transfer reactions, (3) the structure of nuclei far from stability, and (4) ultra-relativistic heavy-ion physics. These results will be described in this document in sections IIA, IIB, and IID, respectively. Areas (1), (3), and (4) concentrate on the structure of nuclear matter in extreme conditions of rotational motion, imbalance of neutrons and protons, or very high temperature and density. Area (2) pursues the transfer of nucleons to states with high angular momentum, both to learn about their structure and to understand the transfer of particles, energy and angular momentum in collisions between heavy ions. An important component of our program is the strong emphasis on the theoretical aspects of nuclear structure and reactions

Nuclear spectroscopic studies

International Nuclear Information System (INIS)

Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

1993-01-01

The Nuclear Physics group at the University of Tennessee, Knoxville is involved in several aspects of heavy-ion physics including both nuclear structure and reaction mechanisms. While our main emphasis is on experimental problems involving heavy-ion accelerators, we have maintained a strong collaboration with several theorists in order to best pursue the physics of our measurements. During the last year we have led several experiments at the Holifield Heavy Ion Research Facility and participated in others at Argonne National Laboratory. Also, we continue to be very active in the collaboration to study ultra-relativistic heavy ion physics utilizing the SPS accelerator at CERN in Geneva, Switzerland and in a RHIC detector R ampersand D project. Our experimental work is in four broad areas: (1) the structure of nuclei at high angular momentum, (2) heavy-ion induced transfer reactions, (3) the structure of nuclei far from stability, and (4) ultra-relativistic heavy-ion physics. The results of studies in these particular areas will be described in this document in sections IIA, IIB, IIC, and IID, respectively. Areas (1), (3), and (4) concentrate on the structure of nuclear matter in extreme conditions of rotational motion, imbalance of neutrons and protons, or very high temperature and density. Area (2) pursues the transfer of nucleons to states with high angular momentum, both to learn about their structure and to understand the transfer of particles, energy, and angular momentum in collisions between heavy ions. An important component of our program is the strong emphasis on the theoretical aspects of nuclear structure and reactions

Nuclear spectroscopic studies

International Nuclear Information System (INIS)

Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

1988-01-01

The Nuclear Physics group at the University of Tennessee, Knoxville is involved in several aspects of heavy-ion physics including both nuclear structure and reaction mechanisms. While our main emphasis is on experimental problems involving heavy-ion accelerators, we have maintained a strong collaboration with several theorists in order to best pursue the physics of our measurements. During the last year we have led experiments at the Holifield Heavy Ion Research Facility, the SuperHILAC at Berkeley, and Chalk River Tandem Accelerator. Also, we have joined a collaboration to study ultra-relativistic heavy ion physics and one of our group has spent all of 1987 at CERN to work on the WA80 experiment. Our experimental work is in four broad areas: (1) the structure of nuclei at high angular momentum, (2) heavy-ion induced transfer reactions, (3) the structure of nuclei far from stability, and (4) ultra-relativistic heavy-ion physics. These results will be described in this document in sections 2A, 2B, 2C, and 2D, respectively. Areas (1), (3), and (4) concentrate on the structure of nuclear matter in extreme conditions of rotational motion, imbalance of neutrons and protons or very high temperature and density. Area (2) pursues the transfer of nucleons to states with high angular momentum, both to learn about their structure and to understand the transfer of particles, energy and angular momentum in collisions between heavy ions. An important component of our program is the strong emphasis on the theoretical aspects of nuclear structure and reactions

Spectral distribution of radiation on plane and axial channeling of ultrarelativistic electrons

International Nuclear Information System (INIS)

Bazylev, V.A.; Glebov, V.I.; Zhevago, N.K.

1980-01-01

The spectral angular and polarization charactristics of the radiation from channeled ultrarelativistic electrons are calculated. Analytic expressions for the spectral-angular power density of the radiation are obtained for some realistic models of the continuous potential of the crystal planes and axes. A critical analysis is also presented of some existent results of the theory of radiation on channeling

Simulation of ultra-relativistic electrons and positrons channeling in crystals with MBN Explorer

DEFF Research Database (Denmark)

Sushko, Gennady B.; Bezchastnov, Victor G.; Solov'yov, Ilia

2013-01-01

A newly developed code, implemented as a part of the MBN Explorer package (Solov'yov et al., 2012; http://www.mbnexplorer.com/, 2012) [1] and [2] to simulate trajectories of an ultra-relativistic projectile in a crystalline medium, is presented. The motion of a projectile is treated classically b...

Dynamics of hadronization in ultra-relativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Friman, B.L.

1986-01-01

One of the main problems in the search for quark-gluon plasma in ultra-relativistic nucleus-nucleus collisions is finding a reliable signature for deconfinement. Several signatures have been suggested, e.g., dileptons with a spectrum characteristic of the plasma, an increase in the number of strange particles and effects due to the hadronization of the plasma. In this talk I will describe some recent work on the effects of the hadronization transition in the central rapidity region within the hydrodynamic model of Bjorken, Kajantie and McLerran. (orig.)

Phase transition dynamics in ultra-relativistic heavy-ion collisions

International Nuclear Information System (INIS)

Csernai, L.P.; Kapusta, J.I.; Kluge, G.Y.; Zabrodin, E.E.

1992-11-01

The authors investigate various problems related to the dynamics of a first-order phase transition from quark-gluon plasma to hadronic matter in ultra-relativistic heavy ion collisions. These include nucleation, growth and fusion of hadronic bubbles in either the Bjorken longitudinal hydrodynamic expansion model or the Cooper-Frye-Schonberg spherical hydrodynamic expansion model. With reasonable input parameters the conversion of one phase into the other is relatively close to the idealized adiabatic Maxwell construction, although one can choose parameters such that the conversion is strongly out of equilibrium. 10 refs., 7 figs

Hirschegg '95: Dynamical properties of hadrons in nuclear matter. Proceedings

International Nuclear Information System (INIS)

Feldmeier, H.; Noerenberg, W.

1995-01-01

The following topics were dealt with: Chiral symmetry, chiral condensates, in-medium effective chiral Lagrangians, Δ's in nuclei, nonperturbative QCD, electron scattering from nuclear matter, nuclear shadowing, QCD sum rules, deconfinement, ultrarelativistic heavy ion collisions, nuclear dimuon and electron pair production, photoproduction from nuclei, subthreshold K + production, kaon polarization in nuclear matter, charged pion production in relativistic heavy ion collisions, the Nambu-Jona-Lasinio model, the SU(3) L xSU(3) R sigma model, nonequilibrium dense nuclear matter, pion pair production at finite temperature. (HSI)

Nuclear spectroscopic studies

International Nuclear Information System (INIS)

Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

1994-01-01

The Nuclear Physics group at UTK is involved in heavy-ion physics including both nuclear structure and reaction mechanisms. During the last year experimental work has been in 3 broad areas: structure of nuclei at high angular momentum, structure of nuclei far from stability, and ultra-relativistic heavy-ion physics. Results in these areas are described in this document under: properties of high-spin states, study of low-energy levels of nuclei far from stability, and high-energy heavy-ion physics (PHENIX, etc.). Another important component of the work is theoretical interpretation of experimental results (Joint Institute for Heavy Ion Research)

The string model of nuclear scattering: an introduction

International Nuclear Information System (INIS)

Werner, Klaus

1995-01-01

We discuss the string model of hadronic and nuclear scattering at ultrarelativistic energies. The man purpose is to treat theoretical concepts common to essentially all successful models: strings, Pomerons, and their marriage int he string model approach. We stay an introductory level without going into technical details. (author)

An overview of nuclear physics research

International Nuclear Information System (INIS)

Kapoor, S.S.

2010-01-01

This overview is aimed to give a general picture of the global developments in nuclear physics research over the years since the beginning. It is based on the inaugural talk given at the 54th annual nuclear physics symposium organized by the Department of Atomic Energy, which was held as an International Symposium at BARC, Mumbai during Dec 8-12, 2009. The topics of nuclear fission, nuclear shell effects, super-heavy nuclei, and expanding frontiers of nuclear physics research with the medium to ultra-relativistic energy heavy-ion reactions are in particular highlighted. Accelerator driven sub-critical reactor system (ADS) is briefly described in the end as an example of spin-off of nuclear physics research. (author)

Nuclear spectroscopic studies: Progress report

International Nuclear Information System (INIS)

Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

1989-01-01

The Nuclear Physics Group at the University of Tennessee, Knoxville (UTK) is involved in several aspects of heavy-ion physics including both nuclear structure and reaction mechanisms. While our main emphasis is on experimental problems involving heavy-ion accelerators, we have maintained a strong collaboration with several theorists in order to best pursue the physics of our measurements. During the last year we have led experiments at the Holifield Heavy Ion Research Facility (HHIRF) and the Niels Bohr Institute Tandem Accelerator. Also, we are active in a collaboration (WA80) to study ultra-relativistic heavy ion physics utilizing the SPS accelerator at CERN in Geneva, Switzerland. Our experimental work is four broad areas: (1) the structure of nuclei at high angular momentum, (2) heavy-ion induced transfer reactions, (3) the structure of nuclei far from stability, and (4) ultra-relativistic heavy-ion physics. These results will be described in this document. Areas (1), (3), and (4) concentrate on the structure of nuclear matter in extreme conditions of rotational motion, imbalance of neutrons and protons, or very high temperature and density. Area (2) pursues the transfer of nucleons to states with high angular momentum, both to learn about their structure and to understand the transfer of particles, energy, and angular momentum in collisions between heavy ions. An important component of our program is the strong emphasis on the theoretical aspects of nuclear structure and reactions

Transparency in high-energy nuclear collisions

International Nuclear Information System (INIS)

Karol, P.J.

1992-01-01

Problems associated with transparency schemes based on sharp cutoff models are discussed. The soft spheres model of hadron-nucleus and nucleus-nucleus collisions has been used to explore the influence of the realistic nuclear density geometry on transparency. An average nuclear transparency and an average reaction transparency are defined and their dependence on target and projectile dimensions and on the hadron-nucleon collision cross section are described. The results are expected to be valid for projectile energies above several hundred MeV/nucleon through the ultrarelativistic regime. For uniform (hard sphere) nuclear profiles, methods for obtaining effective total transparencies are suggested

Femtoscopic analysis of baryon correlations in ultra-relativistic heavy-ion collisions registered by ALICE

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00361630

Heavy-ion collisions at ultra-relativistic energies give a unique possibility to create and to analyse the Quark-Gluon Plasma predicted by the theory of Quantum Chromodynamics. The research on the properties of such state of matter is crucial for understanding the features of the strongly interacting system. Experimental results reveal the collective behaviour of matter created in the heavy-ion collisions at ultra-relativistic energies. The existence of this effect can be verified by the measurement of the transverse mass dependence of the source size extracted using different particle species. Such characteristics can be determined using the analysis technique called femtoscopy. This method is based on the correlations of particles with small relative momenta which originate from the effects of Quantum Statistics as well as the strong and Coulomb Final State Interactions. A recent analysis of the particle production at the highest available collision energies of heavy-ion collisions reveals the puzzling res...

Influence of processes of multiple hadron production on the thermodynamics of matter at ultrarelativistic temperatures

International Nuclear Information System (INIS)

Bugrij, A.I.; Trushchevskij, A.A.; Shadura, V.N.

1987-01-01

A representation for the equation of state of the hadronic matter at ultrarelativistic temperatures is obtained in terms of multiplicity distribution function. The character of the equation of state is shown to be determined by the energy dependence of topological cross sections

Perspectives of Nuclear Physics in the Late Nineties

International Nuclear Information System (INIS)

Nguyen Dinh Dang; Da Hsuan Feng; Nguyen Van Giai

1995-01-01

This book is a collection of 44 papers presented at the International Conference on Nuclear Physics and Related Topics held in Hanoi (Vietnam), 1994. Content of the book contains subjects as follows: 1-Recent development of nuclear theory and related topics including conventional picture of nuclei, relativistic mean field theory, quark picture of nuclei, chaos; 2-Recent developments of experiments relating to radioactive beams, ultrarelativistic heavy-ion collisions; and 3-Applications in astrophysics and metal clusters. (N.H.A)

Nuclear Physics Laboratory annual report, University of Washington April 1992

International Nuclear Information System (INIS)

1992-01-01

This report contains short discusses on topics in the following areas: astrophysics; giant resonances and photonuclear reactions; nucleus-nucleus reactions; fundamental symmetries; accelerator mass spectrometry; medium energy nuclear physics; ultra-relativistic heavy ion collisions; cluster fusion; instrumentation; van de graaff accelerators and ion sources; and computer data acquisition systems

Anomalous passage of ultrarelativistic electrons in thick single crystals in axial channeling

International Nuclear Information System (INIS)

Khokonov, M.K.; Telegin, V.I.

1983-01-01

The dynamics of ultrarelativistic axially channeled electrons in thick crystals is studied. It is revealed that a certain fraction of initial electrons have anomalously large dechanneling depths. It is shown also that the dechanneling depth in heavy and light crystals are comparable. In some cases, the number of channeled electrons can strongly increase at the expense of quasi-channeled electrons. The problem of quasichanneling is also considered. (author)

Anomalous passage of ultrarelativistic electrons in thick single crystals in axial channeling

Energy Technology Data Exchange (ETDEWEB)

Khokonov, M.K. (Moskovskij Gosudarstvennyj Univ. (USSR). Nauchno-Issledovatel' skij Inst. Yadernoj Fiziki); Telegin, V.I. (Gosudarstvennyj Komitet po Ispol' zovaniyu Atomnoj Ehnergii SSSR, Moscow. Inst. Atomnoj Ehnergii)

1983-07-01

The dynamics of ultrarelativistic axially channeled electrons in thick crystals is studied. It is revealed that a certain fraction of initial electrons have anomalously large dechanneling depths. It is shown also that the dechanneling depth in heavy and light crystals are comparable. In some cases, the number of channeled electrons can strongly increase at the expense of quasi-channeled electrons. The problem of quasi-channeling is also considered.

Nuclear spectroscopic studies. Progress report

Energy Technology Data Exchange (ETDEWEB)

Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

1993-02-08

The Nuclear Physics group at the University of Tennessee, Knoxville is involved in several aspects of heavy-ion physics including both nuclear structure and reaction mechanisms. While our main emphasis is on experimental problems involving heavy-ion accelerators, we have maintained a strong collaboration with several theorists in order to best pursue the physics of our measurements. During the last year we have led several experiments at the Holifield Heavy Ion Research Facility and participated in others at Argonne National Laboratory. Also, we continue to be very active in the collaboration to study ultra-relativistic heavy ion physics utilizing the SPS accelerator at CERN in Geneva, Switzerland and in a RHIC detector R&D project. Our experimental work is in four broad areas: (1) the structure of nuclei at high angular momentum, (2) heavy-ion induced transfer reactions, (3) the structure of nuclei far from stability, and (4) ultra-relativistic heavy-ion physics. The results of studies in these particular areas will be described in this document in sections IIA, IIB, IIC, and IID, respectively. Areas (1), (3), and (4) concentrate on the structure of nuclear matter in extreme conditions of rotational motion, imbalance of neutrons and protons, or very high temperature and density. Area (2) pursues the transfer of nucleons to states with high angular momentum, both to learn about their structure and to understand the transfer of particles, energy, and angular momentum in collisions between heavy ions. An important component of our program is the strong emphasis on the theoretical aspects of nuclear structure and reactions.

Nuclear Physics Laboratory annual report, University of Washington April 1992

Energy Technology Data Exchange (ETDEWEB)

1992-07-01

This report contains short discusses on topics in the following areas: astrophysics; giant resonances and photonuclear reactions; nucleus-nucleus reactions; fundamental symmetries; accelerator mass spectrometry; medium energy nuclear physics; ultra-relativistic heavy ion collisions; cluster fusion; instrumentation; van de graaff accelerators and ion sources; and computer data acquisition systems. (LSP)

Nuclear Physics Laboratory annual report, University of Washington April 1992

Energy Technology Data Exchange (ETDEWEB)

Cramer, John G.; Ramirez, Maria G.

1992-01-01

This report contains short discusses on topics in the following areas: astrophysics; giant resonances and photonuclear reactions; nucleus-nucleus reactions; fundamental symmetries; accelerator mass spectrometry; medium energy nuclear physics; ultra-relativistic heavy ion collisions; cluster fusion; instrumentation; van de graaff accelerators and ion sources; and computer data acquisition systems. (LSP)

Nonlinear electrostatic excitations in magnetized dense plasmas with nonrelativistic and ultra-relativistic degenerate electrons

International Nuclear Information System (INIS)

Mahmood, S.; Sadiq, Safeer; Haque, Q.

2013-01-01

Linear and nonlinear electrostatic waves in magnetized dense electron-ion plasmas are studied with nonrelativistic and ultra-relativistic degenerate and singly, doubly charged helium (He + , He ++ ) and hydrogen (H + ) ions, respectively. The dispersion relation of electrostatic waves in magnetized dense plasmas is obtained under both the energy limits of degenerate electrons. Using reductive perturbation method, the Zakharov-Kuznetsov equation for nonlinear propagation of electrostatic solitons in magnetized dense plasmas is derived for both nonrelativistic and ultra-relativistic degenerate electrons. It is found that variations in plasma density, magnetic field intensity, different mass, and charge number of ions play significant role in the formation of electrostatic solitons in magnetized dense plasmas. The numerical plots are also presented for illustration using the parameters of dense astrophysical plasma situations such as white dwarfs and neutron stars exist in the literature. The present investigation is important for understanding the electrostatic waves propagation in the outer periphery of compact stars which mostly consists of hydrogen and helium ions with degenerate electrons in dense magnetized plasmas

[Experimental nuclear physics]. Final report

International Nuclear Information System (INIS)

1991-04-01

This is the final report of the Nuclear Physics Laboratory of the University of Washington on work supported in part by US Department of Energy contract DE-AC06-81ER40048. It contains chapters on giant dipole resonances in excited nuclei, nucleus-nucleus reactions, astrophysics, polarization in nuclear reactions, fundamental symmetries and interactions, accelerator mass spectrometry (AMS), ultra-relativistic heavy ions, medium energy reactions, work by external users, instrumentation, accelerators and ion sources, and computer systems. An appendix lists Laboratory personnel, a Ph. D. degree granted in the 1990-1991 academic year, and publications. Refs., 41 figs., 7 tabs

[Experimental nuclear physics]. Final report

Energy Technology Data Exchange (ETDEWEB)

NONE

1991-04-01

This is the final report of the Nuclear Physics Laboratory of the University of Washington on work supported in part by US Department of Energy contract DE-AC06-81ER40048. It contains chapters on giant dipole resonances in excited nuclei, nucleus-nucleus reactions, astrophysics, polarization in nuclear reactions, fundamental symmetries and interactions, accelerator mass spectrometry (AMS), ultra-relativistic heavy ions, medium energy reactions, work by external users, instrumentation, accelerators and ion sources, and computer systems. An appendix lists Laboratory personnel, a Ph. D. degree granted in the 1990-1991 academic year, and publications. Refs., 41 figs., 7 tabs.

Kinetic theory for radiation interacting with sound waves in ultrarelativistic pair plasmas

International Nuclear Information System (INIS)

Marklund, Mattias; Shukla, Padma K.; Stenflo, Lennart

2006-01-01

A kinetic theory for radiation interacting with sound waves in an ultrarelativistic electron-positron plasma is developed. It is shown that the effect of a spatial spectral broadening of the electromagnetic pulse is to introduce a reduction of the growth rates for the decay and modulational instabilities. Such spectral broadening could be due to a finite pulse coherence length, or through the use of random phase filters, and would stabilize the propagation of electromagnetic pulses

Strange particle correlations measured by the Star experiment in ultra-relativistic heavy ion collisions a RHIC; Etude des correlations de particules etranges mesurees par l'experience STAR dans les collisions d'ions lourds ultra-relativistes au RHIC

Energy Technology Data Exchange (ETDEWEB)

Renault, G

2004-09-01

Non-identical correlation functions allow to study the space-time evolution of the source of particles formed in ultra-relativistic heavy ion collisions. The STAR experiment is dedicated to probe the formation of a new state of nuclear matter called Quark Gluon Plasma. The proton - lambda correlation function is supposed to be more sensitive to bigger source sizes than the proton - proton because of the absence of the final state Coulomb interaction. In this thesis, proton - lambda, anti-proton - anti-lambda, anti-proton - lambda and proton - anti-lambda correlation functions are studied in Au+Au collisions at {radical}S{sub NN} = 200 GeV using an analytical model. The proton - lambda and anti-proton - anti-lambda correlation functions exhibit the same behavior as in previous measurements. The anti-proton - lambda and proton - anti-lambda correlation functions, measured for the first time, show a very strong signal corresponding to the baryon - anti-baryon annihilation channel. Parameterizing the correlation functions has allowed to characterize final state interactions. (author)

Ultra-relativistic heavy ions and cosmic rays

International Nuclear Information System (INIS)

McLerran, L.

1983-05-01

The collisions of ultra-relativistic heavy ions, E/sub /N/ greater than or equal to 1 TeV/nucleon are most interesting, since, at these energies, matter is produced at sufficiently high energy density that a quark-gluon plasma has a good chance to form. Very heavy ions are also most interesting since the matter forms in a larger volume than for light ions, and the matter is at a somewhat higher energy density. At very high energies with very heavy ions there is great flexibility in the experimental signals which might be studied, as well as the nature of the matter which is produced. The fragmentation region and central region provide different environments where a plasma might form. The former is baryon rich while the central region is high temperature with low baryon number density and is not accessible except at very high energies

Black-hole production from ultrarelativistic collisions

International Nuclear Information System (INIS)

Rezzolla, Luciano; Takami, Kentaro

2013-01-01

Determining the conditions under which a black hole can be produced is a long-standing and fundamental problem in general relativity. We use numerical simulations of colliding self-gravitating fluid objects to study the conditions of black-hole formation when the objects are boosted to ultrarelativistic speeds. Expanding on the previous work, we show that the collision is characterized by a type-I critical behaviour, with a black hole being produced for masses above a critical value, M c , and a partially bound object for masses below the critical one. More importantly, we show for the first time that the critical mass varies with the initial effective Lorentz factor 〈γ〉 following a simple scaling of the type M c ∼ K〈γ〉 −1.0 , thus indicating that a black hole of infinitesimal mass is produced in the limit of a diverging Lorentz factor. Furthermore, because a scaling is present also in terms of the initial stellar compactness, we provide a condition for black-hole formation in the spirit of the hoop conjecture. (fast track communication)

Quarks and gluons in nuclear and particle physics

International Nuclear Information System (INIS)

Van Hove, L.

1988-01-01

This paper provides a broad overview of strong interactions, or nuclear forces, as ones understanding has expanded over the past 25 years. The major particles and models are briefly touched upon. The author expands upon the field theories which have evolved to explain the experimental work, and the present model of quarks and gluons which form the components of hadrons. The standard model has been very successful in explaining much of the newly acquired experimental data. But the property of confinement, where the partons, (quarks and gluons), are not observed seperately has precluded observation of these particles. He touches on the manifestation of these particles in high energy physics, where they model the observed particles and resonances, and are responsible for the production of hadronic jets. However in nuclear physics, one does not need to postulate the existance of these particles to explain the properties of nuclei, until one deals with interaction energies in the range of GeV. The author then touches on the area of ultra-relativistic nuclear physics, where the partons must play a role in the effects which are observed. In particular he discusses deep inelastic lepton scattering on nuclei, the Drell-Yan process in nuclei, and ultra-relativistic nuclear collisions. Finally he gives a brief discussion of the quark-gluon plasma, which is postulated to form during very high energy collisions, manifesting itself as a brief deconfinement of the partons into an equilibrium plasma

Ultra-relativistic heavy ions and the CBA

International Nuclear Information System (INIS)

McLerran, L.D.

1982-01-01

The study of ultra-relativistic heavy ions at an accelerator such as the CBA provides a unique glimpse of matter as it may have appeared in the early universe. This hot dense matter very probably appears as a quark-gluon plasma which expands and cools into hadronic matter. The CBA would provide data at the very highest energies, and produce matter at the highest energy densities. The possibility of using a cyclotron to inject very heavy ions into the AGS and then into the CBA would also allow the production of quark-gluon matter at higher energy densities than would light ions, and would make the matter in a larger volume where surface effects are minimized. At the highest energies with very heavy ions, there is great flexibility in the experimental signals which might be studied, as well as the nature of the matter which is produced. Some of the possibilities are discussed

Photons from Ultra-Relativistic Heavy Ion Collisions

CERN Document Server

Sarkar, S

2000-01-01

It is believed that a novel state of matter - Quark Gluon Plasma (QGP) will be transiently produced if normal hadronic matter is subjected to sufficiently high temperature and/or density. We have investigated the possibility of QGP formation in the ultra-relativistic collisions of heavy ions through the electromagnetic probes - photons and dileptons. The formulation of the real and virtual photon production rate from strongly interacting matter is studied in the framework of Thermal Field Theory. Since signals from the QGP will pick up large backgrounds from hadronic matter we have performed a detailed study of the changes in the hadronic properties induced by temperature within the ambit of the Quantum Hadrodynamic model, gauged linear and non-linear sigma models, hidden local symmetry approach and QCD sum rule approach. The possibility of observing the direct thermal photons and lepton pairs from quark gluon plasma has been contrasted with that from hot hadronic matter with and without medium effects for va...

Ultrarelativistic electron and positron radiation in planar channeling

International Nuclear Information System (INIS)

Kalashnikov, N.P.; Olchack, A.S.

1980-01-01

The coherent electromagnetic radiation from channeling electrons and positrons is given by similar expression. However for the channeling positrons the close collisions are suppressed due to the fact that the positron wave function is exponentially small near the atoms of the crystal lattice. It follows that the coherent bremsstrahlung decreases for the channeling positrons. We have investigated the ultrarelativistic channeling electron and positron radiations, connected with the electromagnetic transitions from the continuum spectrum states to the quasi-bound spectrum states and between the different quasi-bound spectrum states. The radiation probabilities are calculated by using the model continuum planar potential. It is shown that the radiation from the channeling electrons is several orders of magnitude larger than the positron radiation, while the electron and positron radiation have similar characteristics such as frequency limitation and angular distribution of the radiation. (orig.)

Theses of reports 'V Conference of high energy physics, nuclear physics and accelerators'

International Nuclear Information System (INIS)

Dovbnya, A.N.

2007-01-01

Nucleus structure study in the reactions on the charged particles; application of the nuclear and physical methods in the adjacent science fields; study and development of accelerators and accumulators of charged particles; basic research in an effort to develop the nuclear and physical methods for the nuclear power needs, medicine and industry; computed engineering in the physical studies; basic research of interaction processes of ultrarelativistic particles with monocrystals and substance; physics of detectors are submitted in proceedings of V Conference on High Energy Physics

Open heavy flavor and other hard probes in ultra-relativistic heavy-ion collisions

OpenAIRE

Uphoff, Jan

2014-01-01

In this thesis hard probes are studied in the partonic transport model BAMPS (Boltzmann Approach to MultiParton Scatterings). Employing Monte Carlo techniques, this model describes the 3+1 dimensional evolution of the quark gluon plasma phase in ultra-relativistic heavy-ion collisions by propagating all particles in space and time and carrying out their collisions according to the Boltzmann equation. Since hard probes are produced in hard processes with a large momentum transfer, the value of...

On the optimal choice of the laminar medium substance for ultrarelativistic particle transition radiation detectors

International Nuclear Information System (INIS)

Avakian, A.L.; Garibian, G.M.; Yang, C.

1975-01-01

The dependence of the X-ray transition yield in the energy region 10-20keV produced by an ultrarelativistic charged particle in various laminar media on the substance of the plates is investigated in detail. It is shown that in this case beryllium is the most optimal substance. Other energy regions of transition radiation quanta are also considered. (Auth.)

Macroscopic damping model for zero degree energy distribution in ultra-relativistic heavy ion collisions

International Nuclear Information System (INIS)

Gao Chongshou; Wang Chengshing

1993-01-01

A macroscopic damping model is proposed to calculate the zero degree energy distribution in ultra-relativistic heavy ion collisions. The main features of the measured distributions are reproduced, good agreement is obtained in the middle energy region while overestimation results on the high energy side. The average energy loss coefficient of incident nucleons, varying in the reasonable region 0.2-0.6, depends on beam energy and target size

Wave speeds in the macroscopic extended model for ultrarelativistic gases

Energy Technology Data Exchange (ETDEWEB)

Borghero, F., E-mail: borghero@unica.it [Dip. Matematica e Informatica, Università di Cagliari, Via Ospedale 72, 09124 Cagliari (Italy); Demontis, F., E-mail: fdemontis@unica.it [Dip. Matematica, Università di Cagliari, Viale Merello 92, 09123 Cagliari (Italy); Pennisi, S., E-mail: spennisi@unica.it [Dip. Matematica, Università di Cagliari, Via Ospedale 72, 09124 Cagliari (Italy)

2013-11-15

Equations determining wave speeds for a model of ultrarelativistic gases are investigated. This model is already present in literature; it deals with an arbitrary number of moments and it was proposed in the context of exact macroscopic approaches in Extended Thermodynamics. We find these results: the whole system for the determination of the wave speeds can be divided into independent subsystems which are expressed by linear combinations, through scalar coefficients, of tensors all of the same order; some wave speeds, but not all of them, are expressed by square roots of rational numbers; finally, we prove that these wave speeds for the macroscopic model are the same of those furnished by the kinetic model.

Progress report on nuclear spectroscopic studies

International Nuclear Information System (INIS)

Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

1994-01-01

The Nuclear Physics group at the University of Tennessee, Knoxville (UTK) is involved in several aspects of heavy-ion physics including both nuclear structure and reaction mechanisms. While the main emphasis is on experimental problems, the authors have maintained a strong collaboration with several theorists in order to best pursue the physics of their measurements. During the last year they have had several experiments at the ATLAS at Argonne National Laboratory, the GAMMASPHERE at the LBL 88 Cyclotron, and with the NORDBALL at the Niels Bohr Institute Tandem. Also, they continue to be very active in the WA93/98 collaboration studying ultra-relativistic heavy ion physics utilizing the SPS accelerator at CERN in Geneva, Switzerland and in the PHENIX Collaboration at the RHIC accelerator under construction at Brookhaven National Laboratory. During the last year their experimental work has been in three broad areas: (1) the structure of nuclei at high angular momentum, (2) the structure of nuclei far from stability, and (3) ultra-relativistic heavy-ion physics. The results of studies in these particular areas are described in this document. These studies concentrate on the structure of nuclear matter in extreme conditions of rotational motion, imbalance of neutrons and protons, or very high temperature and density. Another area of research is heavy-ion-induced transfer reactions, which utilize the transfer of nucleons to states with high angular momentum to learn about their structure and to understand the transfer of particles, energy, and angular momentum in collisions between heavy ions

Simulating of spectrum and polarization characteristics of ultrarelativistic - electron coherent radiation in a diamond crystal

International Nuclear Information System (INIS)

Truten', V.I.

2000-01-01

On the base of the computer simulation method it is shown that new maxima of ultrarelativistic electron radiation spectrum in aligned crystals may appear in a low-frequency region together with the ordinary coherent maxima. The appearance of these maxima is the result of the high-index-crystal-plane effect. These maxima manifest themselves in spectral as well as in polarization features of radiation [ru

Abrupt acceleration of a 'cold' ultrarelativistic wind from the Crab pulsar.

Science.gov (United States)

Aharonian, F A; Bogovalov, S V; Khangulyan, D

2012-02-15

Pulsars are thought to eject electron-positron winds that energize the surrounding environment, with the formation of a pulsar wind nebula. The pulsar wind originates close to the light cylinder, the surface at which the pulsar co-rotation velocity equals the speed of light, and carries away much of the rotational energy lost by the pulsar. Initially the wind is dominated by electromagnetic energy (Poynting flux) but later this is converted to the kinetic energy of bulk motion. It is unclear exactly where this takes place and to what speed the wind is accelerated. Although some preferred models imply a gradual acceleration over the entire distance from the magnetosphere to the point at which the wind terminates, a rapid acceleration close to the light cylinder cannot be excluded. Here we report that the recent observations of pulsed, very high-energy γ-ray emission from the Crab pulsar are explained by the presence of a cold (in the sense of the low energy of the electrons in the frame of the moving plasma) ultrarelativistic wind dominated by kinetic energy. The conversion of the Poynting flux to kinetic energy should take place abruptly in the narrow cylindrical zone of radius between 20 and 50 light-cylinder radii centred on the axis of rotation of the pulsar, and should accelerate the wind to a Lorentz factor of (0.5-1.0) × 10(6). Although the ultrarelativistic nature of the wind does support the general model of pulsars, the requirement of the very high acceleration of the wind in a narrow zone not far from the light cylinder challenges current models.

Nuclear Physics Laboratory, University of Washington annual report

International Nuclear Information System (INIS)

1998-04-01

The Nuclear Physics Laboratory at the University of Washington in Seattle pursues a broad program of nuclear physics. These activities are conducted locally and at remote sites. The current programs include in-house research using the local tandem Van de Graaff and superconducting linac accelerators and non-accelerator research in solar neutrino physics at the Sudbury Neutrino Observatory in Canada and at SAGE in Russia, and gravitation as well as user-mode research at large accelerators and reactor facilities around the world. Summaries of the individual research projects are included. Areas of research covered are: fundamental symmetries, weak interactions and nuclear astrophysics; neutrino physics; nucleus-nucleus reactions; ultra-relativistic heavy ions; and atomic and molecular clusters

Theoretical studies in medium-energy nuclear and hadronic physics. [Indiana Univ. Nuclear Theory Center and Department of Physics

Energy Technology Data Exchange (ETDEWEB)

Horowitz, C J; Macfarlane, M H; Matsui, T; Serot, B D

1993-01-01

A proposal for theoretical nuclear physics research is made for the period April 1, 1993 through March 31, 1996. Research is proposed in the following areas: relativistic many-body theory of nuclei and nuclear matter, quasifree electroweak scattering and strange quarks in nuclei, dynamical effects in (e,e[prime]p) scattering at large momentum transfer, investigating the nucleon's parton sea with polarized leptoproduction, physics of ultrarelativistic nucleus[endash]nucleus collisions, QCD sum rules and hadronic properties, non-relativistic models of nuclear reactions, and spin and color correlations in a quark-exchange model of nuclear matter. Highlights of recent research, vitae of principal investigators, and lists of publications and invited talks are also given. Recent research dealt primarily with medium-energy nuclear physics, relativistic theories of nuclei and the nuclear response, the nuclear equation of state under extreme conditions, the dynamics of the quark[endash]gluon plasma in relativistic heavy-ion collisions, and theories of the nucleon[endash]nucleon force.

Radiation of ultrarelativistic charge taking into account for multiple scattering

International Nuclear Information System (INIS)

Yang, C.

1977-01-01

A brief theoretical review of characteristics of X-rays and more hard radiation formed by an ultrarelativistic charged particle passing through a plate or a stack of plates with regard for multiple scattering and the plate material absorptivity is made. Formulas for frequency- angular and frequency distributions of total radiation in the cases of a plate and of a stack of plates with large spacings as well as a stack of sufficiently thick plates are given. A calculation method for the radiation distributions in a general case of an arbitrary stack is pointed out. The frequency distribution of the total radiation consisting of bremsstrahlung and boundary effects is analyzed in detail. A problem of experimental separation of the boundary effect from the total radiation is discussed

The study of ultrarelativistic heavy ion collisions an introduction to the goals and the status of the results

CERN Document Server

Seyboth, P; Diakonos, F K; Ktorides, C N; Stassinaki, M; Vassiliou, Maria

2000-01-01

The ultimate goal of the study of ultrarelativistic heavy ion collisions is to find evidence for the deconfined phase of hadronic matter, the quark gluon plasma (QGP), which is expected to form under conditions of extremely high energy and/or matter density. One knows that hadrons are composed of color neutral aggregates of quarks, antiquarks and gluons which are confined to regions of finite size (radius~0.8 fm) by color forces. When e.g. nucleons are compressed to sufficiently high density (>or approximately=1 fm/sup -3/) they must start to overlap and confinement of quarks and gluons to individual nucleons is expected to disappear. Such conditions are thought to prevail in neutron stars, which may thus contain cold QGP in their core (temperature T approximately=0, density rho >8 rho /sub 0/, where rho /sub 0/ is the normal nuclear matter density). In the early universe the energy density was presumably extremely high. Consequently the number density of quarks, antiquarks and gluons was likewise extremely l...

Book of abstracts of the 9th Conference on High Energy Physics, Nuclear Physics and Accelerators

International Nuclear Information System (INIS)

Dovbnya, A.N.

2011-01-01

The conference is devoted to the fundamental investigations at intermediate and high energies; also, the nuclear structure in reactions with charged particles; application of nuclear-physical methods to associated fields; investigation and development of accelerators, and of charged particles storage rings; the fundamental investigation and development of nuclear physical methods as applied in atomic energetics, medicine and industry; an application of the computer technologies for physical studies; fundamental investigations of processes of the ultrarelativistic particle interactions with monocrystals and matter; and physics of detectors.

Population of multi-quark states in exotic multiplets and thermalization in ultra-relativistic heavy ion collisions

International Nuclear Information System (INIS)

Scherer, S.; Bleicher, M.; Haussler, S.; Stoecker, H.

2008-01-01

The recent discussion about experimental evidence for pentaquark states has revitalized the interest in exotic hadrons. If such states really exist, it is natural to assume that they will be formed at the late hadronization stage of ultra-relativistic heavy ion collisions, given the success of quark recombination models in the description of hadronization. Here, we apply the qMD model to study the formation of color neutral exotic multi-quark clusters at hadronization. We search for color neutral clusters made up of up to six color charges, respectively. We thus obtain estimates for the numbers and phase space distributions of exotic hadronic states produced by clustering in heavy ion collisions, including the members of the pentaquark multiplets. We obtain particle abundances that are smaller than thermal model predictions. Moreover, the results obtained in recombination from ultra-relativistic heavy ion collisions can be compared to the estimates based on equal population of the corresponding multiplets, and to results from fully thermalized systems. We find that the distribution of exotic hadrons from recombination over large multiplets provides a sensitive signal for thermalization and decorrelation of the initial, non-equilibrium state of the collision. (author)

Numerical studies of acceleration of thorium ions by a laser pulse of ultra-relativistic intensity

Directory of Open Access Journals (Sweden)

Domanski Jaroslaw

2018-01-01

Full Text Available One of the key scientific projects of ELI-Nuclear Physics is to study the production of extremely neutron-rich nuclides by a new reaction mechanism called fission-fusion using laser-accelerated thorium (232Th ions. This research is of crucial importance for understanding the nature of the creation of heavy elements in the Universe; however, they require Th ion beams of very high beam fluencies and intensities which are inaccessible in conventional accelerators. This contribution is a first attempt to investigate the possibility of the generation of intense Th ion beams by a fs laser pulse of ultra-relativistic intensity. The investigation was performed with the use of fully electromagnetic relativistic particle-in-cell code. A sub-μm thorium target was irradiated by a circularly polarized 20-fs laser pulse of intensity up to 1023 W/cm2, predicted to be attainable at ELI-NP. At the laser intensity ~ 1023 W/cm2 and an optimum target thickness, the maximum energies of Th ions approach 9.3 GeV, the ion beam intensity is > 1020 W/cm2 and the total ion fluence reaches values ~ 1019 ions/cm2. The last two values are much higher than attainable in conventional accelerators and are fairly promising for the planned ELI-NP experiment.

Electromagnetic production of Higgs bosons, SUSY particles, glueballs and mesons in ultrarelativistic heavy-ion collisions

International Nuclear Information System (INIS)

Greiner, M.; Soff, G.

1992-12-01

The electromagnetic creation of various exotic particles in ultrarelativistic heavy-ion collisions is discussed. The production of intermediate mass Higgs bosons of the minimal supersymmetric extension of the Standard Model is enhanced over the Standard Model Higgs boson formation for certain model parameter choices and as a consequence might be detectable at LCH and SSC. We also investigate the electromagnetic generation of supersymmetric fermions and bosons as well as glueballs, mesons and fermions. (orig.)

Explaining the Diverse Response of the Ultra-relativistic Van Allen Radiation Belt to Solar Wind Forcing

Science.gov (United States)

Mann, I. R.; Ozeke, L.; Murphy, K. R.; Claudepierre, S. G.; Rae, J.; Milling, D. K.; Kale, A.; Baker, D. N.

2017-12-01

The NASA Van Allen Probes have opened a new window on the dynamics of ultra-relativistic electrons in the Van Allen radiation belts. Under different solar wind forcing the outer belt is seen to respond in a variety of apparently diverse and sometimes remarkable ways. For example, sometimes a third radiation belt is carved out (e.g., September 2012), or the belts can remain depleted for 10 days or more (September 2014). More usually there is a sequential response of a strong and sometimes rapid depletion followed by a re-energization, the latter increasing outer belt electron flux by orders of magnitude on hour timescales during some of the strongest storms of this solar cycle (e.g., March 2013, March 2015). Such dynamics also appear to be often bounded at low-L by an apparently impenetrable barrier at L 2.8 through which ultra-relativistic electrons do not penetrate. Many studies in the Van Allen Probes era have sought explanations for these apparently diverse features, often incorporating the effects from multiple plasma waves. In contrast, we show how this apparently diverse behaviour can instead be explained by one dominant process: ULF wave radial transport. Once ULF wave transport rates are accurately specified by observations, and coupled to the dynamical variation of the outer boundary condition at the edge of the outer belt, the observed diverse responses can all be explained. However, in order to get good agreement with observations, the modeling reveals the importance of still currently unexplained very fast loss in the main phase which results in an almost total extinction of the belts and decouples pre- and post-storm ultra-relativistic electron flux on hour timescales. Similarly, varying plasmasheet source populations are seen to be of critical importance such that near-tail dynamics play a crucial role in Van Allen belt dynamics. Nonetheless, simple models incorporating accurate transport rates derived directly from ULF wave measurements are shown to

Observation of Global Hyperon Polarization in Ultrarelativistic Heavy-Ion Collisions

Science.gov (United States)

Upsal, Isaac; STAR Collaboration

2017-11-01

Collisions between heavy nuclei at ultra-relativistic energies form a color-deconfined state of matter known as the quark-gluon plasma. This state is well described by hydrodynamics, and non-central collisions are expected to produce a fluid characterized by strong vorticity in the presence of strong external magnetic fields. The STAR Collaboration at Brookhaven National Laboratory's Relativistic Heavy Ion Collider (RHIC) has measured collisions between gold nuclei at center of mass energies √{sNN} = 7.7- 200 GeV. We report the first observation of globally polarized Λ and Λ bar hyperons, aligned with the angular momentum of the colliding system. These measurements provide important information on partonic spin-orbit coupling, the vorticity of the quark-gluon plasma, and the magnetic field generated in the collision.

University of Washington, Nuclear Physics Laboratory annual report, 1995

International Nuclear Information System (INIS)

1995-04-01

The Nuclear Physics Laboratory of the University of Washington supports a broad program of experimental physics research. The current program includes in-house research using the local tandem Van de Graff and superconducting linac accelerators and non-accelerator research in double beta decay and gravitation as well as user-mode research at large accelerator and reactor facilities around the world. This book is divided into the following areas: nuclear astrophysics; neutrino physics; nucleus-nucleus reactions; fundamental symmetries and weak interactions; accelerator mass spectrometry; atomic and molecular clusters; ultra-relativistic heavy ion collisions; external users; electronics, computing, and detector infrastructure; Van de Graff, superconducting booster and ion sources; nuclear physics laboratory personnel; degrees granted for 1994--1995; and list of publications from 1994--1995

Theoretical studies in medium-energy nuclear and hadronic physics

International Nuclear Information System (INIS)

Horowitz, C.J.; Macfarlane, M.H.; Matsui, T.; Serot, B.D.

1993-01-01

A proposal for theoretical nuclear physics research is made for the period April 1, 1993 through March 31, 1996. Research is proposed in the following areas: relativistic many-body theory of nuclei and nuclear matter, quasifree electroweak scattering and strange quarks in nuclei, dynamical effects in (e,e'p) scattering at large momentum transfer, investigating the nucleon's parton sea with polarized leptoproduction, physics of ultrarelativistic nucleus endash nucleus collisions, QCD sum rules and hadronic properties, non-relativistic models of nuclear reactions, and spin and color correlations in a quark-exchange model of nuclear matter. Highlights of recent research, vitae of principal investigators, and lists of publications and invited talks are also given. Recent research dealt primarily with medium-energy nuclear physics, relativistic theories of nuclei and the nuclear response, the nuclear equation of state under extreme conditions, the dynamics of the quark endash gluon plasma in relativistic heavy-ion collisions, and theories of the nucleon endash nucleon force

Suitability of high-current standing-wave linac technology for ultra-relativistic electron beam propagation experiments

International Nuclear Information System (INIS)

Moir, D.C.; Faehl, R.J.; Newberger, B.S.; Thode, L.E.

1981-01-01

Near-term development of the existing PHERMEX standing-wave linac would provide a 40 to 60 MeV electron beam with a current of 3 kA capable of answering a number of fundamental issues concerning endoatmospheric, ultra-relativistic electron beam propagation. Inherent high-repetition rate and multiple-pulse capability would allow alternative propagation scenarios to be investigated. Much of the theoretical expertise required to support the technology development and time-resolved beam propagation experiments presently resides within the Theoretical Applications Division

Glenn T. Seaborg and heavy ion nuclear science

International Nuclear Information System (INIS)

Loveland, W.

1992-04-01

Radiochemistry has played a limited but important role in the study of nucleus-nucleus collisions. Many of the important radiochemical studies have taken place in Seaborg's laboratory or in the laboratories of others who have spent time in Berkeley working with Glenn T. Seaborg. I will discuss studies of low energy deep inelastic reactions with special emphasis on charge equilibration, studies of the properties of heavy residues in intermediate energy nuclear collisions and studies of target fragmentation in relativistic and ultrarelativistic reactions. The emphasis will be on the unique information afforded by radiochemistry and the physical insight derived from radiochemical studies. Future roles of radiochemistry in heavy ion nuclear science also will be discussed

Ultra-relativistic heavy-ion collisions - a hot cocktail of hydrodynamics, resonances and jets

Directory of Open Access Journals (Sweden)

Zabrodin E.

2015-01-01

Full Text Available Ultra-relativistic heavy-ion collisions at energies of RHIC and LHC are considered. For comparison with data the HYDJET++ model, which contains the treatment of both soft and hard processes, is employed. The study focuses mainly on the interplay of ideal hydrodynamics, final state interactions and jets, and its influence on the development of harmonics of the anisotropic flow. It is shown that jets are responsible for violation of the number-of-constituent-quark (NCQ scaling at LHC energies. The interplay between elliptic and triangular flows and their contribution to higher flow harmonics and dihadron angular correlations, including ridge, is also discussed.

The radiative deceleration of ultrarelativistic jets in active galactic nuclei

International Nuclear Information System (INIS)

Melia, F.; Konigl, A.

1989-01-01

A detailed study of the dynamical interaction between a highly relativistic jet and the thermal radiation field from an AGN accretion disk is reported, and the Comptonized spectrum arising from this interaction is self-consistently determined. A simple model that captures the essential radiative and geometrical features of realistic disk configurations is presented, and the disk radiation field is calculated. The results confirm Phinney's (1987) suggestion that the thermal radiation field produced by accretion in an AGN could be very effective in decelerating ultrarelativistic jets that are accreted by electromagnetic or hydromagnetic forces closer to the central black hole. Terminal Lorentz factors are consistent with the values inferred in superluminal radio sources are readily produced in this model for plausible disk and jet parameters without additional acceleration in the interaction zone. A new interpretation of the hard X-ray component detected in BL Lac spectra is proposed. 55 refs

Simulating the spectrum and the polarization characteristics of coherent radiation from ultrarelativistic electrons in a diamond crystal

International Nuclear Information System (INIS)

Truten', V.I.

2000-01-01

On the basis of a computer simulation, it is shown that, in the spectrum of radiation from ultrarelativistic electrons in oriented crystals, new maxima can appear in the low-frequency region in addition to ordinary coherent maxima. This effect is due to the influence of high-index planes on the radiation in question. The aforementioned new maxima manifest themselves not only in the spectrum but also in the polarization characteristics of the radiation

Search for (exotic) strange matter in the Star and Alice experiments with the ultra-relativistic heavy ion colliders RHIC and LHC; Recherche de matiere etrange (exotique) dans les experiences STAR et ALICE aupres des collisionneurs d'ions lourds ultra-relativistes RHIC et LHC

Energy Technology Data Exchange (ETDEWEB)

Vernet, R

2006-02-15

Ultra-relativistic heavy ion collisions offer the possibility to create conditions of temperature and density that could lead nuclear matter to a state of deconfined partons, the quark-gluon plasma. Strange baryon production is one of the essential observables to understand the mechanisms involved in the medium. Furthermore, theories predict a possible production of strange dibaryons, still hypothetical particles, from which one could draw important inferences in nuclear physics and astrophysics. The experiments STAR at RHIC, and, soon, ALICE at LHC, allow one to search for strange baryons and dibaryons. The STAR sensitivity to the metastable dibaryon H{sup 0} in the {lambda}p{pi}{sup -} decay mode was calculated thanks to a dedicated simulation. The search for the H{sup 0}, and for the {xi}{sup -}p resonance as well, was performed in the STAR Au+Au data at {radical}(s{sub NN}) = 62.4 and 200 GeV energies. Within the framework of the preparation of ALICE to the first Pb+Pb data, the detector ability to identify strange baryons {lambda}, {xi} and {omega}, was estimated via several simulations. So as to favour the reconstruction efficiency in a large range of transverse momentum while keeping a reasonable S/B ratio, the influence of the geometrical selections and the size of the reconstruction zone was emphasized. The ALICE sensitivities to the metastable strange dibaryons H{sup 0} and ({xi}{sup 0}p){sub b} and to the {lambda}{lambda} resonance were calculated as well. (author)

Volume reflection and channeling of ultrarelativistic protons in germanium bent single crystals

Directory of Open Access Journals (Sweden)

S. Bellucci

2016-12-01

Full Text Available The paper is devoted to the investigation of volume reflection and channeling processes of ultrarelativistic positive charged particles moving in germanium single crystals. We demonstrate that the choice of atomic potential on the basis of the Hartree-Fock method and the correct choice of the Debye temperature allow us to describe the above mentioned processes in a good agreement with the recent experiments. Moreover, the universal form of equations for volume reflection presented in the paper gives a true description of the process at a wide range of particle energies. Standing on this study we make predictions for the mean angle reflection (as a function of the bending radius of positive and negative particles for germanium (110 and (111 crystallographic planes.

What we have (not)learned from the ultrarelativistic heavy ion collisions

International Nuclear Information System (INIS)

Paic, Guy

2009-01-01

The field of ultrarelativistic heavy ion collisions is today a flourishing activity both on the experimental and on the theoretical side. Although the theoretical justifications to study these collisions was given already more than three decades ago and the experimental studies have a history of more than 25 years we are still very much in the dark as to the details of the processes and of the characteristics of the matter created in collisions. Increasing the energy of collisions has brought new insights but has also resulted with new challenges. In the present paper I will try from a personal perspective to report on the answers we have collected and on the problems we are faced with. The account is partial, taking into account that it is impossible to render justice to every aspect of the field.

Nonlinear screening effect in an ultrarelativistic degenerate electron-positron gas

International Nuclear Information System (INIS)

Tsintsadze, N. L.; Rasheed, A.; Shah, H. A.; Murtaza, G.

2009-01-01

Nonlinear screening process in an ultrarelativistic degenerate electron-positron gas has been investigated by deriving a generalized nonlinear Poisson equation for the electrostatic potential. In the simple one-dimensional case, the nonlinear Poisson equation leads to Debye-like (Coulomb-like) solutions at distances larger (less) than the characteristic length. When the electrostatic energy is larger than the thermal energy, this nonlinear Poisson equation converts into the relativistic Thomas-Fermi equation whose asymptotic solution in three dimensions shows that the potential field goes to zero at infinity much more slowly than the Debye potential. The possibility of the formation of a bound state in electron-positron plasma is also indicated. Further, it is investigated that the strong spatial fluctuations of the potential field may reduce the screening length and that the root mean square of this spatial fluctuating potential goes to zero for large r rather slowly as compared to the case of the Debye potential.

Electromagnetically-induced nuclear-charge pickup observed in ultra-relativistic Pb collisions

International Nuclear Information System (INIS)

Scheidenberger, C.; Aumann, T.; Pshenichnov, I.A.; Russian Academy of Sciences, Moscow

2002-01-01

A strong increase of inclusive nuclear-charge pickup cross sections, forming 83 Bi from 158 A GeV 82 Pb ions, is observed in comparison to similar measurements at 10.6 A GeV. From the dependence of these cross sections on target atomic number, this increase is attributed to the electromagnetic process of pion production by equivalent photons. The observed cross sections can be reproduced quantitatively using the recently developed RELDIS code. (orig.)

Hot Quarks 2016: Workshop for young scientists on the physics of ultrarelativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

2017-01-01

The 7th edition of the Workshop for Young Scientists on the Physics of Ultra-relativistic Nucleus-Nucleus Collisions (Hot Quarks 2016) was held on South Padre Island, Texas, United States from September 12-17, 2016. Following the traditions of the conference, the meeting gathered almost 70 participants in the first years of their scientific careers. The present issue contains the proceedings of this workshop.As in the past, the Hot Quarks workshop offered a unique atmosphere for lively discussions and interpretation of the current measurements from high-energy nuclear collisions. Dedicated time at the end of each session for questions, including anonymous questions from the “box”, are crucial for this workshop. Recent results and upgrades at CERN's Large Hadron Collider (LHC) and Brookhaven's Relativistic Heavy Ion Collider (RHIC) were presented. Recent theoretical developments were also extensively discussed as well as the perspectives for future facilities such as the Facility for Antiproton and Ion Research (FAIR) at Darmstadt and the Electron-Ion Collider at Brookhaven. The conference's goal to provide a platform for young researchers to learn and foster their interactions was successfully met.We wish to thank the sponsors of the Hot Quarks 2016 Conference, who supported the authors of this volume: European Laboratory for Particle Physics CERN (Switzerland), Cyclotron Institute at Texas A and M University (USA), ExtreMe Matter Institute EMMI (Germany), Helmholtz Association and GSI under grant VH-NG-822 (Germany), Helmholtz International Center for FAIR (Germany), National Science Foundation (USA), Netherlands Organization for Scientific Research (Netherlands), Nuclear Physics Institute of the CAS (Czech Republic), the Ministry of Education, Youth and Sport (Czech Republic) and 3 sponsors who wish to remain anonymous.Javier López Albacete, Universidad de Granada (Spain)Jana Bielcikova, Nuclear Physics Inst. of the Czech Academy of Sciences

Search for (exotic) strange matter in the Star and Alice experiments with the ultra-relativistic heavy ion colliders RHIC and LHC

International Nuclear Information System (INIS)

Vernet, R.

2006-02-01

Ultra-relativistic heavy ion collisions offer the possibility to create conditions of temperature and density that could lead nuclear matter to a state of deconfined partons, the quark-gluon plasma. Strange baryon production is one of the essential observables to understand the mechanisms involved in the medium. Furthermore, theories predict a possible production of strange dibaryons, still hypothetical particles, from which one could draw important inferences in nuclear physics and astrophysics. The experiments STAR at RHIC, and, soon, ALICE at LHC, allow one to search for strange baryons and dibaryons. The STAR sensitivity to the metastable dibaryon H 0 in the Λpπ - decay mode was calculated thanks to a dedicated simulation. The search for the H 0 , and for the Ξ - p resonance as well, was performed in the STAR Au+Au data at √(s NN ) = 62.4 and 200 GeV energies. Within the framework of the preparation of ALICE to the first Pb+Pb data, the detector ability to identify strange baryons Λ, Ξ and Ω, was estimated via several simulations. So as to favour the reconstruction efficiency in a large range of transverse momentum while keeping a reasonable S/B ratio, the influence of the geometrical selections and the size of the reconstruction zone was emphasized. The ALICE sensitivities to the metastable strange dibaryons H 0 and (Ξ 0 p) b and to the ΛΛ resonance were calculated as well. (author)

Dispersion characteristics of anisotropic unmagnetized ultra-relativistic transverse plasma wave with arbitrary electron degeneracy

Science.gov (United States)

Sarfraz, M.; Farooq, H.; Abbas, G.; Noureen, S.; Iqbal, Z.; Rasheed, A.

2018-03-01

Thermal momentum space anisotropy is ubiquitous in many astrophysical and laboratory plasma environments. Using Vlasov-Maxwell's model equations, a generalized polarization tensor for a collisionless ultra-relativistic unmagnetized electron plasma is derived. In particular, the tensor is obtained by considering anisotropy in the momentum space. The integral of moments of Fermi-Dirac distribution function in terms of Polylog functions is used for describing the border line plasma systems (T/e TF e ≈1 ) comprising arbitrary electron degeneracy, where Te and TF e, are thermal and Fermi temperatures, respectively. Furthermore, the effects of variation in thermal momentum space anisotropy on the electron equilibrium number density and the spectrum of electromagnetic waves are analyzed.

Search for nuclei in heavy ion collisions at ultrarelativistic energies

CERN Multimedia

2002-01-01

We would like to know if nuclei are still present after a collision of two heavy ions at ultrarelativistic energies. If one can detect some of them at large angle $(>10^{\\circ}-15^{\\circ})$ they very likely come from a multifragmentation of the excited target spectators. Such a multifragmentation in several nuclei has been in proton induced reactions at Fermilab and it was interpreted as a gas-liquid phase transition in nuclei matter near the critical point. With heavy ions the energy deposited in the target spectators will be much higher than in the case of protons and a different mechanism should be involved if nuclei are still observed. \\\\ \\\\ We propose to detect nuclei using 1-2 silicon telescopes and a 1-2mg/cm$^{2}$ Au target bombarded by an $^{16}$O or $^{32}$S beam at 226 GeV/u. The set-up will be installed in a small cube located just before the NA38 experiment and should not perturb it.\\\\ \\\\ Data from $^{16}$O incident on Au have been taken last year. The experiment is presently taking data with $^{...

Pion production in relativistic collisions of nuclear drops

International Nuclear Information System (INIS)

Alonso, C.T.; Wilson, J.R.; McAbee, T.L.; Zingman, J.A.

1988-09-01

In a continuation of the long-standing effort of the nuclear physics community to model atomic nuclei as droplets of a specialized nuclear fluid, we have developed a hydrodynamic model for simulating the collisions of heavy nuclei at relativistic speeds. Our model couples ideal relativistic hydrodynamics with a new Monte Carlo treatment of dynamic pion production and tracking. The collective flow for low-energy (200 MeV/N) collisions predicted by this model compares favorably with results from earlier hydrodynamic calculations which used quite different numerical techniques. Our pion predictions at these lower energies appear to differ, however, from the experimental data on pion multiplicities. In this case of ultra-relativistic (200 GeV/N) collisions, our hydrodynamic model has produced baryonic matter distributions which are in reasonable agreement with recent experimental data. These results may shed some light on the sensitivity of relativistic collision data to the nuclear equation of state. 20 refs., 12 figs

A model for neutrino emission from nuclear accretion disks

Science.gov (United States)

Deaton, Michael

2015-04-01

Compact object mergers involving at least one neutron star can produce short-lived black hole accretion engines. Over tens to hundreds of milliseconds such an engine consumes a disk of hot, nuclear-density fluid, and drives changes to its surrounding environment through luminous emission of neutrinos. The neutrino emission may drive an ultrarelativistic jet, may peel off the disk's outer layers as a wind, may irradiate those winds or other forms of ejecta and thereby change their composition, may change the composition and thermodynamic state of the disk itself, and may oscillate in its flavor content. We present the full spatial-, angular-, and energy-dependence of the neutrino distribution function around a realistic model of a nuclear accretion disk, to inform future explorations of these types of behaviors. Spectral Einstein Code (SpEC).

Strangeness in hot and dense nuclear matter

International Nuclear Information System (INIS)

Nappi, E.

2009-01-01

Ultra-relativistic heavy-ion collisions are believed to provide the extreme conditions of energy densities able to lead to a transition to a short-lived state, called Quark-Gluon Plasma (QGP), where the quarks are no longer bound inside hadrons. The studies performed so far, formerly at SPS (CERN) and later at RHIC (BNL) allowed to achieve a multitude of crucial results consistent with the hypothesis that a new phase of the QCD matter has been indeed created. However, the emerging picture is that of the formation of a strongly interacting medium with negligibly small viscosity, a perfect liquid, rather than the ideal perturbative QCD parton-gas predicted by most theorists. The head-on collision between lead nuclei at the unprecedented energies of the forthcoming Large Hadron Collider (LHC) at CERN, due to start in 2008, will allow to measure the properties of compressed and excited nuclear matter at even higher initial densities and temperatures, far above the predicted QCD phase transition point. The longer duration of the quark-gluon plasma phase and the much more abundant production of hard probes, which depend much less on details of the later hadronic phase, will likely provide a consistent and uncontroversial experimental evidence of the QGP formation. Among the signals what witness the charge in the nature of the state of nuclear matter, the chemical equilibrium value of the strangeness plays a key role since it is directly sensitive to the matter properties and provides information on the link between the partonic and the hadronic phases. The aim of this course is to overview the underlying goals, the current status and the prospect of the physics of the nucleus-nucleus collisions at ultrarelativistic energies. Among the experimental methods adopted to investigate the challenging signatures of the QGP formation, emphasis on those related to the strangeness flavour will be given.

Partial correlation analysis method in ultrarelativistic heavy-ion collisions

Science.gov (United States)

Olszewski, Adam; Broniowski, Wojciech

2017-11-01

We argue that statistical data analysis of two-particle longitudinal correlations in ultrarelativistic heavy-ion collisions may be efficiently carried out with the technique of partial covariance. In this method, the spurious event-by-event fluctuations due to imprecise centrality determination are eliminated via projecting out the component of the covariance influenced by the centrality fluctuations. We bring up the relationship of the partial covariance to the conditional covariance. Importantly, in the superposition approach, where hadrons are produced independently from a collection of sources, the framework allows us to impose centrality constraints on the number of sources rather than hadrons, that way unfolding of the trivial fluctuations from statistical hadronization and focusing better on the initial-state physics. We show, using simulated data from hydrodynamics followed with statistical hadronization, that the technique is practical and very simple to use, giving insight into the correlations generated in the initial stage. We also discuss the issues related to separation of the short- and long-range components of the correlation functions and show that in our example the short-range component from the resonance decays is largely reduced by considering pions of the same sign. We demonstrate the method explicitly on the cases where centrality is determined with a single central control bin or with two peripheral control bins.

Approximative analytic study of fermions in magnetar's crust; ultra-relativistic plane waves, Heun and Mathieu solutions and beyond

Science.gov (United States)

Dariescu, Marina-Aura; Dariescu, Ciprian

2012-10-01

Working with a magnetic field periodic along Oz and decaying in time, we deal with the Dirac-type equation characterizing the fermions evolving in magnetar's crust. For ultra-relativistic particles, one can employ the perturbative approach, to compute the conserved current density components. If the magnetic field is frozen and the magnetar is treated as a stationary object, the fermion's wave function is expressed in terms of the Heun's Confluent functions. Finally, we are extending some previous investigations on the linearly independent fermionic modes solutions to the Mathieu's equation and we discuss the energy spectrum and the Mathieu Characteristic Exponent.

On the estimation of the wake potential for an ultrarelativistic charge in an accelerating structure

International Nuclear Information System (INIS)

Novokhatskij, A.V.

1988-01-01

The method to derive the analytic estimations for wake fields of an ultrarelativistic charge in an accelerating structure, that are valid in the range of distances smalller or compared to the effective structure dimensions. The method is based on the approximate space-time domain integrating of the maxwell equations in the Kirchhoff formulation. the method is demonstrated on the examples of obtaining the wake potentials for energy loss of a bunch traversing a scraper, a cavity or periodic iris-loaded structure. Likewise formulae are derived for Green functions that describe transverse force action of wake fields. Simple formulae for the total energy loss evaluation of a bunch with the Gaussian charge density distribution are derived as well. The derived estimations are compared with the computer results and predictions of other models

Multiple electromagnetic pair production in ultrarelativistic heavy ion collisions

International Nuclear Information System (INIS)

Best, C.

1992-04-01

The problem of the unitary violation in the pair production in ultrarelativistic heavy ion collisions was studied by a consideration of the field-theoretical foundations. The quantum electrodynamics in an external field were thereby reduced to a Dirac-sea model, the equivalence of which to the non-radiative QED resulted from the equality of the generating functionals. The latter can both be expressed explicitely by means of the complet set of the solutions of the Dirac equation in an external field. This method is based solely on the path-integral approach, which makes it possible to discriminate clearly between the physically given correlation functions and their generating functional at the one hand and at the other hand between the models constructed to their interpretation. From the model expression for the pair production amplitudes and multiplicities could be calculated, for which only the knowledge of the one-particle S matrix is necessary. For the calculation of the multiplicities different forms of the perturbation theory were discussed. Finally an impact-parameter dependent Weizsaecker-Williams approximation for the calculation of arbitrary two-photon graphs was constructed and applied to the given problem. The results indicate that at small distances very high pair multiplicities are to be expected. Finally a new approach to the pair production in an external field was discussed, which is not based on the canonical field theory, but on the formalism of the Wigner functions. (orig./HSI) [de

Numerical solution of special ultra-relativistic Euler equations using central upwind scheme

Science.gov (United States)

Ghaffar, Tayabia; Yousaf, Muhammad; Qamar, Shamsul

2018-06-01

This article is concerned with the numerical approximation of one and two-dimensional special ultra-relativistic Euler equations. The governing equations are coupled first-order nonlinear hyperbolic partial differential equations. These equations describe perfect fluid flow in terms of the particle density, the four-velocity and the pressure. A high-resolution shock-capturing central upwind scheme is employed to solve the model equations. To avoid excessive numerical diffusion, the considered scheme avails the specific information of local propagation speeds. By using Runge-Kutta time stepping method and MUSCL-type initial reconstruction, we have obtained 2nd order accuracy of the proposed scheme. After discussing the model equations and the numerical technique, several 1D and 2D test problems are investigated. For all the numerical test cases, our proposed scheme demonstrates very good agreement with the results obtained by well-established algorithms, even in the case of highly relativistic 2D test problems. For validation and comparison, the staggered central scheme and the kinetic flux-vector splitting (KFVS) method are also implemented to the same model. The robustness and efficiency of central upwind scheme is demonstrated by the numerical results.

Physical mechanism causing rapid changes in ultrarelativistic electron pitch angle distributions right after a shock arrival: Evaluation of an electron dropout event

Science.gov (United States)

Zhang, X.-J.; Li, W.; Thorne, R. M.; Angelopoulos, V.; Ma, Q.; Li, J.; Bortnik, J.; Nishimura, Y.; Chen, L.; Baker, D. N.; Reeves, G. D.; Spence, H. E.; Kletzing, C. A.; Kurth, W. S.; Hospodarsky, G. B.; Blake, J. B.; Fennell, J. F.

2016-09-01

Three mechanisms have been proposed to explain relativistic electron flux depletions (dropouts) in the Earth's outer radiation belt during storm times: adiabatic expansion of electron drift shells due to a decrease in magnetic field strength, magnetopause shadowing and subsequent outward radial diffusion, and precipitation into the atmosphere (driven by EMIC wave scattering). Which mechanism predominates in causing electron dropouts commonly observed in the outer radiation belt is still debatable. In the present study, we evaluate the physical mechanism that may be primarily responsible for causing the sudden change in relativistic electron pitch angle distributions during a dropout event observed by Van Allen Probes during the main phase of the 27 February 2014 storm. During this event, the phase space density of ultrarelativistic (>1 MeV) electrons was depleted by more than 1 order of magnitude over the entire radial extent of the outer radiation belt (3 pitch angle distribution under a compressed magnetic field topology based on actual solar wind conditions. Although these ultrarelativistic electrons exhibit highly anisotropic (peaked in 90°), energy-dependent pitch angle distributions, which appear to be associated with the typical EMIC wave scattering, comparison of the modeled electron distribution to electron measurements indicates that drift shell splitting is responsible for this rapid change in electron pitch angle distributions. This further indicates that magnetopause loss is the predominant cause of the electron dropout right after the shock arrival.

Interferometric probes of ultrarelativistic nuclear collisions

Energy Technology Data Exchange (ETDEWEB)

Padula, S.S. (Instituto de Fisica Teorica, Sao Paulo (Brazil)); Gyulassy, M. (Lawrence Berkeley Lab., CA (USA). Nuclear Science Div.)

1991-04-01

We suggest that pion and kaon interferometry are complementary probes that help differentiate hadronic resonance gas from plasma dynamical models. We also discuss how interferometry could be used to test the presence of resonances at AGS energies. Finally, we study the A dependence of interferometry in the resonance model at 200 A GeV. (orig.).

Interferometric probe of ultrarelativistic nuclear collisions

International Nuclear Information System (INIS)

Padula, S.S.; Gyulassy, M.

1990-01-01

We suggest that pion and kaon interferometry are complementary probles that help differentiate hadronic resonance gas from plasma dynamical models. We also discuss how interferometry could be used to test the presence of resonances at AGS energies. Finally, we study the A dependence of interferometry in the resonance model at 200 A GeV. (author) [pt

Interferometric probes of ultrarelativistic nuclear collisions

International Nuclear Information System (INIS)

Padula, S.S.; Gyulassy, M.

1991-01-01

We suggest that pion and kaon interferometry are complementary probes that help differentiate hadronic resonance gas from plasma dynamical models. We also discuss how interferometry could be used to test the presence of resonances at AGS energies. Finally, we study the A dependence of interferometry in the resonance model at 200 A GeV. (orig.)

Experimental Nuclear Physics Activity in Italy

Science.gov (United States)

Chiavassa, E.; de Marco, N.

2003-04-01

The experimental Nuclear Physics activity of the Italian researchers is briefly reviewed. The experiments, that are financially supported by the INFN, are done in strict collaboration by more than 500 INFN and University researchers. The experiments cover all the most important field of the modern Nuclear Physics with probes extremely different in energy and interactions. Researches are done in all the four National Laboratories of the INFN even if there is a deeper involvement of the two national laboratories expressly dedicated to Nuclear Physics: the LNL (Laboratorio Nazionale di Legnaro) and LNS (Laboratorio Nazionale del Sud) where nuclear spectroscopy and reaction dynamics are investigated. All the activities with electromagnetic probes develops in abroad laboratories as TJNAF, DESY, MAMI, ESFR and are dedicated to the studies of the spin physics and of the nucleon resonance; hypernuclear and kaon physics is investigated at LNF. A strong community of researchers work in the relativistic and ultra-relativistic heavy ions field in particular at CERN with the SPS Pb beam and in the construction of the ALICE detector for heavy-ion physics at the LHC collider. Experiments of astrophysical interest are done with ions of very low energy; in particular the LUNA accelerator facility at LNGS (Laboratorio Nazionale del Gran Sasso) succeeded measuring cross section at solar energies, below or near the solar Gamow peak. Interdisciplinary researches on anti-hydrogen atom spectroscopy and on measurements of neutron cross sections of interest for ADS development are also supported.

Nuclear suppression at large forward rapidities in d-Au collisions at relativistic and ultrarelativistic energies

Czech Academy of Sciences Publication Activity Database

Nemchik, J.; Petráček, Vojtěch; Potashnikova, I.K.; Šumbera, Michal

2008-01-01

Roč. 78, č. 2 (2008), 025213/1-025213/5 ISSN 0556-2813 R&D Projects: GA ČR GA202/07/0079 Institutional research plan: CEZ:AV0Z10480505 Keywords : GLUON DISTRIBUTION-FUNCTIONS * SMALL-X * TRANSVERSE -MOMENTUM Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.124, year: 2008

Ultrarelativistic boost of a black hole in the magnetic universe of Levi-Civita-Bertotti-Robinson

Science.gov (United States)

Ortaggio, Marcello; Astorino, Marco

2018-05-01

We consider an exact Einstein-Maxwell solution constructed by Alekseev and Garcia, which describes a Schwarzschild black hole immersed in the magnetic universe of Levi-Civita, Bertotti, and Robinson (LCBR). After reviewing the basic properties of this spacetime, we study the ultrarelativistic limit in which the black hole is boosted to the speed of light, while sending its mass to 0. This results in a nonexpanding impulsive wave traveling in the LCBR universe. The wave front is a 2-sphere carrying two null point particles at its poles—a remnant of the structure of the original static spacetime. It is also shown that the obtained line element belongs to the Kundt class of spacetimes, and the relation with the known family of exact gravitational waves of finite duration propagating in the LCBR background is clarified. In the limit of a vanishing electromagnetic field, one point particle is pushed away to infinity and the single-particle Aichelburg-Sexl p p -wave propagating in Minkowski space is recovered.

Jet probes of the nuclear and proton wavefunctions in proton--lead collisions with the ATLAS detector

CERN Document Server

Perepelitsa, Dennis; The ATLAS collaboration

2014-01-01

Measurements of high pT processes in ultrarelativistic proton-nucleus collisions are sensitive to changes in the partonic densities arising from the presence of the high-density nuclear environment. Such measurements are thought to serve as a benchmark of the so called "cold nuclear matter" effects, providing the context within which to understand the strong suppression of high pT processes observed in nucleus-nucleus collisions. However, measurements of the centrality dependence of jet production at forward (proton-going) rapidities may additionally shed light on the behavior of the proton wavefunction at large Bjorken-x. The latest ATLAS results for inclusive jets and charged particles in 31/nb of 5.02 TeV proton-lead collisions at the LHC are presented. The centrality in these collisions is characterized through the sum of the transverse energy in the lead-going forward calorimeter. The nuclear modification factors RpPb and RCP are presented for jets and high-pT charged particles as a function of transvers...

Total spectrum of photon emission by an ultra-relativistic positron channelling in a periodically bent crystal

International Nuclear Information System (INIS)

Krause, W.; Korol, A.V.; Department of Physics, St Petersburg State Maritime Technical University, Leninskii prospect 101, St Petersburg 198262; Solov'yov, A.V.; AF Ioffe Physical-Technical Institute of the Academy of Sciences of Russia, Polytechnicheskaya 26, St Petersburg 194021; Greiner, W.

2000-01-01

We present the results of numerical calculations of the channelling and undulator radiation generated by ultra-relativistic positron channelling along a crystal plane, which is periodically bent. The bending might be due to either the propagation of a transverse acoustic wave through the crystal, or the static strain as it occurs in superlattices. The periodically bent crystal serves as an undulator. We investigate the dependence of the intensities of both the ordinary channelling and the undulator radiations on the parameters of the periodically bent channel with simultaneous account for the de-channelling effect of the positrons. We demonstrate that there is a range of parameters in which the undulator radiation dominates over the channelling one and the characteristic frequencies of both types of radiation are well separated. This result is important, because the undulator radiation can be used to create a tunable source of x-ray and γ-radiation. (author). Letter-to-the-editor

Final Report for Project ``Theory of ultra-relativistic heavy-ion collisions''

Energy Technology Data Exchange (ETDEWEB)

Ulrich W. Heinz

2012-11-09

In the course of this project the Ohio State University group led by the PI, Professor Ulrich Heinz, developed a comprehensive theoretical picture of the dynamical evolution of ultra-relativistic heavy-ion collisions and of the numerous experimental observables that can be used to diagnose the evolving and short-lived hot and dense fireball created in such collisions. Starting from a qualitative understanding of the main features based on earlier research during the last decade of the twentieth century on collisions at lower energies, the group exploited newly developed theoretical tools and the stream of new high-quality data from the Relativistic Heavy Ion Collider at Brookhaven National Laboratory (which started operations in the summer of the year 2000) to arrive at an increasingly quantitative description of the experimentally observed phenomena. Work done at Ohio State University (OSU) was instrumental in the discovery during the years 2001-2003 that quark-gluon plasma (QGP) created in nuclear collisions at RHIC behaves like an almost perfect liquid with minimal viscosity. The tool of relativistic fluid dynamics for viscous liquids developed at OSU in the years 2005-2007 opened the possibility to quantitatively determine the value of the QGP viscosity empirically from experimental measurements of the collective flow patterns established in the collisions. A first quantitative extraction of the QGP shear viscosity, with controlled theoretical uncertainty estimates, was achieved during the last year of this project in 2010. OSU has paved the way for a transition of the field of relativistic heavy-ion physics from a qualitative discovery stage to a new stage of quantitative precision in the description of quark-gluon plasma properties. To gain confidence in the precision of our theoretical understanding of quark-gluon plasma dynamics, one must test it on a large set of experimentally measured observables. This achievement report demonstrates that we have, at

Nuclear dependence of Drell-Yan and J/ψ production in FNAL E866

International Nuclear Information System (INIS)

Tribble, R.E.; Beddo, M.E.; Brown, C.N.; Carey, T.A.; Chang, T.H.; Cooper, W.E.; Gagliardi, C.A.; Garvey, G.T.; Geesaman, D.F.; Hawker, E.A.; He, X.C.; Isenhower, L.D.; Kaufman, S.B.; Kaplan, D.M.; Koetke, D.D.; Lee, W.M.; Leitch, M.J.; McGaughey, P.L.; Moss, J.M.; Mueller, B.A.; Papavassiliou, V.; Peng, J.C.; Petitt, G.; Reimer, P.E.; Sadler, M.E.; Stankus, P.W.; Sondheim, W.E.; Towell, R.S.; Vasiliev, M.A.; Webb, J.C.; Willis, J.L.; Young, G.R.

2000-01-01

Fermilab E866 has measured the target-mass dependence of Drell-Yan and J/ψ dimuon production induced by an 800 GeV proton beam on targets of Be, Fe and W. Clear evidence of nuclear shadowing is observed in the Drell-Yan cross section ratios per nucleon at small x 2 . The x 1 dependence of the cross section ratios provides a determination of the energy loss of ultra-relativistic quarks as they pass through cold nuclei. Preliminary results for J/ψ yields show maximum cross section ratios that are slightly less than 1 at an x F value near 0.1. The yield on heavy targets is much more strongly suppressed relative to light targets at larger values of x F

Event shape analysis in ultrarelativistic nuclear collisions

OpenAIRE

Kopecna, Renata; Tomasik, Boris

2016-01-01

We present a novel method for sorting events. So far, single variables like flow vector magnitude were used for sorting events. Our approach takes into account the whole azimuthal angle distribution rather than a single variable. This method allows us to determine the good measure of the event shape, providing a multiplicity-independent insight. We discuss the advantages and disadvantages of this approach, the possible usage in femtoscopy, and other more exclusive experimental studies.

Simulating ultra-relativistic nuclear collisions: Screening corrections

Indian Academy of Sciences (India)

werner@nanhp2 (Klaus WERNER,,,)

It is an effective theory based on the Gribov–Regge formalism, ... sidering particle production (in particular in Monte–Carlo applications), but not for cross- .... That means the interaction's probability of proton's components is decreased by.

Open heavy flavor and other hard probes in ultra-relativistic heavy-ion collisions

International Nuclear Information System (INIS)

Uphoff, Jan

2013-01-01

In this thesis hard probes are studied in the partonic transport model BAMPS (Boltzmann Approach to MultiParton Scatterings). Employing Monte Carlo techniques, this model describes the 3+1 dimensional evolution of the quark gluon plasma phase in ultra-relativistic heavy-ion collisions by propagating all particles in space and time and carrying out their collisions according to the Boltzmann equation. Since hard probes are produced in hard processes with a large momentum transfer, the value of the running coupling is small and their interactions should be describable within perturbative QCD (pQCD). This work focuses on open heavy flavor, but also addresses the suppression of light parton jets, in particular to highlight differences due to the mass. For light partons, radiative processes are the dominant contribution to their energy loss. For heavy quarks, we show that also binary interactions with a running coupling and an improved Debye screening matched to hard-thermal-loop calculations play an important role. Furthermore, the impact of the mass in radiative interactions, prominently named the dead cone effect, and the interplay with the Landau-Pomeranchuk-Migdal (LPM) effect are studied in great detail. Since the transport model BAMPS has access to all medium properties and the space time information of heavy quarks, it is the ideal tool to study the dissociation and regeneration of J/ψ mesons, which is also investigated in this thesis.

On a temporal evolution of the ultra-relativistic electron spectrum by action of synchrotron losses and turbulent acceleration

International Nuclear Information System (INIS)

Samsonov, A.M.; Fedorenko, V.N.

1981-01-01

The kinetic equation describing temporal evolution of the ultra-relativistic electrons' energy spectrum effected by synchrotron losses and turbulent acceleration is solved for the isotropic part of the electrons' distribution function. The original distribution is assumed to be given in the form of a power spectrum. Turbulence properties are stated by means of the turbulent acceleration coefficient depending on epsilon energy D(epsilon)=D 0 epsilon 3 which is related to the synchrotron losses coefficient b(epsilon)=b 0 epsilon 3 so that the isotropization of the distribution function is provided without essential acceleration of particles. The initial spectrum is conserved up to some values of time t and energy epsilon connected by inequality epsilonb 0 t 0 /D 0 -2 if epsilonD 0 t>>1 and b 0 >>D 0 . Finally, are possible applications of the solution to description of processes in supernova shells and radio galaxies are discussed [ru

Momentum dependence in pair production by an external field

Science.gov (United States)

Asakawa, M.

1992-08-01

The transverse and the longitudinal momentum dependences of the pair production under an adiabatically exerted uniform abelian external field are calculated with their importance in models for the production of quark-gluon plasma in ultrarelativistic heavy ion collisions in mind. The importance of the initial condition is revealed. We show that superposition of acceleration by the external field and barrier penetration is reflected in the longitudinal momentum dependence. The peculiar nature of the boost invariant system which is expected to be approximately realized in ultrarelativistic nuclear collisions is pointed out.

Momentum dependence in pair production by an external field

International Nuclear Information System (INIS)

Asakawa, M.

1992-01-01

The transverse and the longitudinal momentum dependences of the pair production under an adiabatically exerted uniform abelian external field are calculated with their importance in models for the production of quark-gluon plasma in ultrarelativistic heavy ion collisions in mind. The importance of the initial condition is revealed. We show that superposition of acceleration by the external field and barrier penetration is reflected in the longitudinal momentum dependence. The peculiar nature of the boost invariant system which is expected to be approximately realized in ultrarelativistic nuclear collisions is pointed out. (orig.)

[Studies of target fragmentation in intermediate energy, relativistic and ultra-relativistic nuclear collisions

International Nuclear Information System (INIS)

Loveland, W.D.

1991-08-01

The work described herein is part of a project involving the study of low energy ( 250 MeV/A) heavy ion reactions. In the low energy regime, we published a monograph on the properties of the heaviest elements and used that publication as a basis for making a set of ''best'' semi-empirical predictions of heavy element decay properties. The intermediate energy research effort focussed upon the completion of studies already begun and the initiation of a number of new experiments. In our study of a interaction of 21 MeV/nucleon 129 Xe with 197 Au, we compared the characteristics of the observed deep inelastic phenomena with various models of dissipative reactions and found significant discrepancies between observations and predictions. These discrepancies seemed to be caused by an improper treatment of pre-equilibrium in the early stages of the collision. In our study of the relativistic interaction of 400 MeV/nucleon 12 C with 197 Au, we reported the first direct physical measurement of the properties of the spallation residues from a nucleus-nucleus collision. We found the residue energies to be much lower than those predicted by the intranuclear cascade model, indicating some substantial modifications of that model are needed. But, we also found, indications of significant, non-zero values of the residue transverse momentum, a finding that calls into question the interpretation of a number of radiochemical recoil studies of the kinematics of high energy reactions. A program of performing numerical simulations of intermediate and high energy nuclear collisions using the QMD model was initiated

(Studies of target fragmentation in intermediate energy, relativistic and ultra-relativistic nuclear collisions)

Energy Technology Data Exchange (ETDEWEB)

Loveland, W.D.

1991-08-01

The work described herein is part of a project involving the study of low energy (< 10 MeV/A), intermediate energy (10--100 MeV/A) and relativistic (> 250 MeV/A) heavy ion reactions. In the low energy regime, we published a monograph on the properties of the heaviest elements and used that publication as a basis for making a set of best'' semi-empirical predictions of heavy element decay properties. The intermediate energy research effort focussed upon the completion of studies already begun and the initiation of a number of new experiments. In our study of a interaction of 21 MeV/nucleon {sup 129}Xe with {sup 197}Au, we compared the characteristics of the observed deep inelastic phenomena with various models of dissipative reactions and found significant discrepancies between observations and predictions. These discrepancies seemed to be caused by an improper treatment of pre-equilibrium in the early stages of the collision. In our study of the relativistic interaction of 400 MeV/nucleon {sup 12}C with {sup 197}Au, we reported the first direct physical measurement of the properties of the spallation residues from a nucleus-nucleus collision. We found the residue energies to be much lower than those predicted by the intranuclear cascade model, indicating some substantial modifications of that model are needed. But, we also found, indications of significant, non-zero values of the residue transverse momentum, a finding that calls into question the interpretation of a number of radiochemical recoil studies of the kinematics of high energy reactions. A program of performing numerical simulations of intermediate and high energy nuclear collisions using the QMD model was initiated.

From elementary particles to stars

International Nuclear Information System (INIS)

Besliu, C.; Jipa, Al.

1999-01-01

The 50th anniversary of National Institute of Physics and Nuclear Engineering (IFIN-HH) coincides with half a century from the discovery of relativistic heavy ions in the primary cosmic radiation. Therefore, an analysis of connections between Particle Physics and Cosmology seems to be indicated at this anniversary. The Relativistic Nuclear Physics could be a bridge between the two fields. Important information on the Universe evolution after Big-Bang, can be obtained in ultrarelativistic nuclear collisions. To compare the processes following the Big Bang with those of quark-gluon plasma formation, expected at collider energies, it is necessary to know the thermodynamic conditions for each stage as well as the time evolution of the systems. In this work, some comparisons of the experimental results and simulations on thermodynamic parameters obtained in relativistic and ultrarelativistic nuclear collisions are discussed and compared with some recent cosmological observations. The existence of similar values of the thermodynamic parameters for equivalent moments in the evolutions of the two systems could be an important tool in a deeper understanding of the Universe. (authors)

People and things. CERN Courier, Mar 1979, v. 19(1)

Energy Technology Data Exchange (ETDEWEB)

Anon.

1979-03-15

The article reports on various achievements of CERN staff members and gives news updates on upcoming or past events, for example the First Workshop on Ultra-Relativistic Nuclear Collisions, or the CERN 25th Anniversary Celebrations.

People and things. CERN Courier, Mar 1979, v. 19(1)

International Nuclear Information System (INIS)

Anon.

1979-01-01

The article reports on various achievements of CERN staff members and gives news updates on upcoming or past events, for example the First Workshop on Ultra-Relativistic Nuclear Collisions, or the CERN 25th Anniversary Celebrations

Physical mechanism causing rapid changes in ultrarelativistic electron pitch angle distributions right after a shock arrival: Evaluation of an electron dropout event: Drift Shell Splitting on the Dayside

International Nuclear Information System (INIS)

Zhang, X.-J.; University of California, Los Angeles, CA; Li, W.; Boston University, MA; Thorne, R. M.

2016-01-01

Three mechanisms have been proposed to explain relativistic electron flux depletions (dropouts) in the Earth's outer radiation belt during storm times: adiabatic expansion of electron drift shells due to a decrease in magnetic field strength, magnetopause shadowing and subsequent outward radial diffusion, and precipitation into the atmosphere (driven by EMIC wave scattering). Which mechanism predominates in causing electron dropouts commonly observed in the outer radiation belt is still debatable. In the present study, we evaluate the physical mechanism that may be primarily responsible for causing the sudden change in relativistic electron pitch angle distributions during a dropout event observed by Van Allen Probes during the main phase of the 27 February 2014 storm. During this event, the phase space density of ultrarelativistic (>1MeV) electrons was depleted by more than 1 order of magnitude over the entire radial extent of the outer radiation belt (3 < L* < 5) in less than 6 h after the passage of an interplanetary shock. We model the electron pitch angle distribution under a compressed magnetic field topology based on actual solar wind conditions. Although these ultrarelativistic electrons exhibit highly anisotropic (peaked in 90°), energy-dependent pitch angle distributions, which appear to be associated with the typical EMIC wave scattering, comparison of the modeled electron distribution to electron measurements indicates that drift shell splitting is responsible for this rapid change in electron pitch angle distributions. This further indicates that magnetopause loss is the predominant cause of the electron dropout right after the shock arrival.

[University of Washington Nuclear Physics Laboratory] annual report, 1991

International Nuclear Information System (INIS)

1991-04-01

This report contains brief papers on the following topics: giant dipole resonances in excited nuclei; nucleus-nucleus reactions; astrophysics; polarization; fundamental symmetries and interactions; accelerator mass spectrometry; ultra-relativistic heavy ions; medium energy interactions; instrumentation; accelerators and ion sources; and computer systems

An overview of experimental results from ultra-relativistic heavy-ion collisions at the CERN LHC: Hard probes

Directory of Open Access Journals (Sweden)

Panagiota Foka

2016-11-01

Full Text Available The first collisions of lead nuclei, delivered by the CERN Large Hadron Collider (LHC at the end of 2010, at a centre-of-mass energy per nucleon pair sNN= 2.76 TeV, marked the beginning of a new era in ultra-relativistic heavy-ion physics. The study of the properties of the produced hot and dense strongly-interacting matter at these unprecedented energies is currently experimentally pursued by all four big LHC experiments, ALICE, ATLAS, CMS, and LHCb. The more than a factor 10 increase of collision energy at LHC, relative to the previously achieved maximal energy at other collider facilities, results in an increase of production rates of hard probes. This review presents selected experimental results focusing on observables probing hard processes in heavy-ion collisions delivered during the first three years of the LHC operation. It also presents the first results from Run 2 heavy-ion data at the highest energy, as well as from the studies of the reference pp and p–Pb systems, which are an integral part of the heavy-ion programme. Keywords: Large Hadron Collider, Heavy-ion collisions, High energy physics

Field theoretic renormalization study of reduced quantum electrodynamics and applications to the ultrarelativistic limit of Dirac liquids

Science.gov (United States)

Teber, S.; Kotikov, A. V.

2018-04-01

The field theoretic renormalization study of reduced quantum electrodynamics (QED) is performed up to two loops. In the condensed matter context, reduced QED constitutes a very natural effective relativistic field theory describing (planar) Dirac liquids, e.g., graphene and graphenelike materials, the surface states of some topological insulators, and possibly half-filled fractional quantum Hall systems. From the field theory point of view, the model involves an effective (reduced) gauge field propagating with a fractional power of the d'Alembertian in marked contrast with usual QEDs. The use of the Bogoliubov-Parasiuk-Hepp-Zimmermann prescription allows for a simple and clear understanding of the structure of the model. In particular, in relation with the ultrarelativistic limit of graphene, we straightforwardly recover the results for both the interaction correction to the optical conductivity C*=(92 -9 π2)/(18 π ) and the anomalous dimension of the fermion field γψ(α ¯ ,ξ )=2 α ¯ (1 -3 ξ )/3 -16 (ζ2NF+4 /27 ) α¯ 2+O (α¯ 3) , where α ¯=e2/(4 π )2 and ξ is the gauge-fixing parameter.

High energy nuclear collisions: Theory overview

Indian Academy of Sciences (India)

1012 K, were deconfined and existed as a quark gluon plasma (QGP). These ideas can be tested in collisions of nuclei at ultra-relativistic energies. At the relativistic heavy-ion collider (RHIC), nuclei as heavy as gold are accelerated to an energy of 100 GeV per nucleon. A total energy of 40 TeV is available in the collision of.

Theoretical trends in interferometry of ultrarelativistic nuclear collisions

International Nuclear Information System (INIS)

Padula, S.S.

1990-01-01

A review is made of the main concepts of interferometry, since its discovery in the mid 50's as the HBT effect, until recently, where some new approaches to the field were suggested. A few modifications on the correlation function in the case of high energy collisions are discussed and illustrated. (author)

Ultrarelativistic nucleus-nucleus collisions at CERN

International Nuclear Information System (INIS)

Odyniec, G.

1989-10-01

The aim of the NA-35 experiment is to study nuclear matter under extreme conditions. Evidence that conditions reached in 60 GeV/N and 200 GeV/N relativistic heavy ion collisions are adequate for the formation of a quark-gluon plasma where color would no longer be confined to hadronic dimensions is presented. Future plans for experiments in 1990--1991 with 32 S beams and 1993 and up with Pb beams at the SPS are discussed. 26 refs., 23 figs., 3 tabs

24th Annual Seminar on theoretical physics, Pretoria, 10-14 July 1989

International Nuclear Information System (INIS)

1989-01-01

This seminar contains 14 papers which are all indexed separately. Topics covered include: real-time green functions in perturbative thermal field theories; non-perturbative calculations in cavity-QCD; cavity-QCD in a background field and hadrons containing a heavy quark; the quark self-energy in a cavity; the hadron spectrum from lattice QCD; exotic hadrons and the isospin delection rule in K → π π decays; nucleon form factors in the relavistic harmonic oscillator potential for quarks; a dirac description of nuclear polarized beam scattering; coherent nuclear energy levels in a supermanifold; macroscopic description of low-lying isovector 1 + states in deformed nuclei; J/ψ suppression in ultra-relativistic heavy ion collisions; transport coefficients in ultra-relativistic heavy ion collisions; decay of interactions during dislocation unbinding in adlayers; and influence of electron-magnon interaction on electronic and magnetic properties of ferromagnetic 4f-systems

Sulphur dissociation in nuclear emulsion at 3.7 and 200A GeV

Energy Technology Data Exchange (ETDEWEB)

El-Nadi, M.; Abdelsalam, A.; Shaat, E.A.; Abou Moussa, Z. [Physics Department, Faculty of Science, Cairo University, Giza (Egypt); Hussien, A. [Physics Department, Faculty of Science, Cairo University, Fayoum Branch, Fayoum (Egypt); Ali-Mossa, N. [Basic Science Department, Faculty of Engineering, Banha Branch, Zagazig University, Banha (Egypt); Kamel, S.; Hafiz, M.E. [Physics Department, Faculty of Education, Ain Shams University, Cairo (Egypt); Abdel-Waged, K.H. [Physics Department, Faculty of Science, Zagazig University, Banha (Egypt)

2002-02-01

In this work, the electromagnetic dissociation (EMD) of sulphur projectile induced by two widely differing energies in nuclear emulsions is investigated. Although the percentages of EMD events of the total numbers of studied interactions are relatively small, i.e. 5.7 and 14.4% for 3.7 and 200A GeV interactions respectively, one could extract some results out of them. The emission of a proton through the {sup 32}S({gamma}, p){sup 31}P channel is found to be a dominant process (43.8%) at 200A GeV whereas the single alpha emission through the {sup 32}S({gamma}, {alpha}){sup 28}Si channel is the dominant one (34.0%) at 3.7A GeV. Multiplicity distributions of hydrogen and helium isotopes as well as the measured probabilities for the different modes of fragmentation are studied. The comparison of the present results, from electromagnetic and peripheral nuclear interactions, indicates the effective role of the different reaction mechanisms at ultra-relativistic energy (200A GeV). The experimental inclusive cross sections of different fragmentation modes produced in the EMD of {sup 32}S ions at 200A GeV were found to be in satisfactory agreement with the predictions of the combined approach of Pshenichnov et al. (author)

Study of electron pair production in hadron and nuclear collisions at the CERN SPS

CERN Multimedia

Liebold, H-P; Sako, H; Belaga, V; Bielcikova, J; Stachel, J

2002-01-01

The NA45/CERES experiment investigates primarily the production of electron-positron pairs and of direct photons in proton-nucleus and nucleus-nucleus collisions. For electron-positron pairs the experiment studies the continuum in the mass region of about 0.05 to 2 GeV/c$^2$ and the vector mesons $\\varrho ,~ \\omega$, and, $\\phi$. Since for electromagnetic probes final state interactions are practically negligible these observables are unique for studying the evolution and dynamics of ultrarelativistic heavy-ion collisions from the hot and dense early stage where a quark-gluon plasma is expected to be formed to the final freeze-out stage when hadrons decouple.\\\\ \\\\ The experiment also studies the spectral distributions of charged particles, their distribution relative to the reaction plane, and identified high momentum pions. Another topic of investigation are QED pairs produced in peripheral nuclear collisions.\\\\ \\\\ The first phase of the experiment, NA45, has been concluded with two main results: i) There is...

Electromagnetic probes of strongly interacting matter

Indian Academy of Sciences (India)

2015-05-07

May 7, 2015 ... The nuclear matter under extreme conditions of temperatures () and baryonic densities () undergoes a phase transition to quark gluon plasma (QGP). It is expected that such extreme conditions can be achieved by colliding nuclei at ultrarelativistic energies. In the present review, the suitability of ...

Dynamical instabilities in quark-gluon plasma with hard jet

International Nuclear Information System (INIS)

Pavlenko, O.P.

1990-01-01

The dynamical instabilities, whose development can be expected under the hard jet propagating through the quark-gluon plasma, are analyzed. The possible signals of the quark-gluon plasma formation in ultrarelativistic nuclear collisions connected with the development of the plasma-jet instabilities are discussed. 10 refs

Production of intermediate-mass dileptons in relativistic heavy ion collisions

International Nuclear Information System (INIS)

Kvasnikova, Ioulia; Gale, Charles; Kumar Srivastava, Dinesh

2002-01-01

The production of intermediate-mass dileptons in ultrarelativistic nuclear collisions at SPS energies is studied. The acceptance and detector resolution inherent to measurements by the NA50 experimental collaboration are accurately modeled. The measured centrality dependence of the intermediate mass lepton pair excess is also addressed

Observation of Global Hyperon Polarization in Ultrarelativistic Heavy-Ion Collisions

Czech Academy of Sciences Publication Activity Database

Upsal, I.; Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Bielčík, J.; Bielčíková, Jana; Chaloupka, P.; Federič, Pavol; Rusňák, Jan; Rusňáková, O.; Šimko, Miroslav; Šumbera, Michal; Vértési, Robert

2017-01-01

Roč. 967, č. 11 (2017), s. 760-763 ISSN 0375-9474 R&D Projects: GA MŠk LG15001; GA MŠk LM2015054 Institutional support: RVO:61389005 Keywords : STAR collaboration * heavy ion collisions * quark-gluon plasma Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders OBOR OECD: Nuclear physics Impact factor: 1.916, year: 2016

Nuclear Science Division annual report, October 1, 1986--September 30, 1987

International Nuclear Information System (INIS)

Mahoney, J.

1988-09-01

This report summarizes the activities of the Nuclear Science Division during the period October 1, 1986 to September 30, 1987. A highlight of the experimental program during this time was the completion of the first round of heavy-ion running at CERN with ultrarelativistic oxygen and sulfur beams. Very rapid progress is being made in the analysis of these important experiments and preliminary results are presented in this report. During this period, the Bevalac also continued to produce significant new physics results, while demand for beam time remained high. An important new community of users has arrived on the scene, eager to exploit the unique low-energy heavy-beam capabilities of the Bevalac. Another major highlight of the program has been the performance of the Dilepton Spectrometer which has entered into production running. Dileptons have been observed in the p + Be and Ca + Ca reactions at several bombarding energies. New data on pion production with heavy beams measured in the streamer chamber to shed light on the question of nuclear compressibility, while posing some new questions concerning the role of Coulomb forces on the observed pion spectra. In another quite different area, the pioneering research with radioactive beams is continuing and is proving to be one of the fastest growing programs at the Bevalac. Exotic secondary beams (e.g., 8He, 11Li, and 14Be) have been produced for fundamental nuclear physics studies. In order to further enhance the scientific research program and ensure the continued vitality of the facility, the Laboratory has proposed an upgrade of the existing Bevalac. Specifically, the Upgrade would replace the Bevatron with a modern, strong-focusing synchrotron to provide higher intensity and higher quality beams to continue the forefront research program. Other papers on nuclear physics research are included in this report

Nuclear Science Division annual report, October 1, 1986--September 30, 1987

Energy Technology Data Exchange (ETDEWEB)

Mahoney, J. (ed.)

1988-09-01

This report summarizes the activities of the Nuclear Science Division during the period October 1, 1986 to September 30, 1987. A highlight of the experimental program during this time was the completion of the first round of heavy-ion running at CERN with ultrarelativistic oxygen and sulfur beams. Very rapid progress is being made in the analysis of these important experiments and preliminary results are presented in this report. During this period, the Bevalac also continued to produce significant new physics results, while demand for beam time remained high. An important new community of users has arrived on the scene, eager to exploit the unique low-energy heavy-beam capabilities of the Bevalac. Another major highlight of the program has been the performance of the Dilepton Spectrometer which has entered into production running. Dileptons have been observed in the p + Be and Ca + Ca reactions at several bombarding energies. New data on pion production with heavy beams measured in the streamer chamber to shed light on the question of nuclear compressibility, while posing some new questions concerning the role of Coulomb forces on the observed pion spectra. In another quite different area, the pioneering research with radioactive beams is continuing and is proving to be one of the fastest growing programs at the Bevalac. Exotic secondary beams (e.g., 8He, 11Li, and 14Be) have been produced for fundamental nuclear physics studies. In order to further enhance the scientific research program and ensure the continued vitality of the facility, the Laboratory has proposed an upgrade of the existing Bevalac. Specifically, the Upgrade would replace the Bevatron with a modern, strong-focusing synchrotron to provide higher intensity and higher quality beams to continue the forefront research program. Other papers on nuclear physics research are included in this report.

An overview of experimental results from ultra-relativistic heavy-ion collisions at the CERN LHC: Bulk properties and dynamical evolution

Directory of Open Access Journals (Sweden)

Panagiota Foka

2016-11-01

Full Text Available The first collisions of lead nuclei, delivered by the CERN Large Hadron Collider (LHC at the end of 2010, at a centre-of-mass energy per nucleon pair sNN= 2.76 TeV, marked the beginning of a new era in ultra-relativistic heavy-ion physics. Following the Run 1 period, LHC also successfully delivered Pb–Pb collisions at the collision energy sNN= 5.02 TeV at the end of 2015. The study of the properties of the produced hot and dense strongly-interacting matter at these unprecedented energies is experimentally pursued by all four big LHC experiments, ALICE, ATLAS, CMS, and LHCb. This review presents selected experimental results from heavy-ion collisions delivered during the first three years of the LHC operation focusing on the bulk matter properties and the dynamical evolution of the created system. It also presents the first results from Run 2 heavy-ion data at the highest energy, as well as from the studies of the reference pp and p–Pb systems, which are an integral part of the heavy-ion programme. Keywords: Large hadron collider, Heavy-ion collisions, High energy physics

Nuclear Science Division annual report for the period October 1, 1987--September 30, 1988

International Nuclear Information System (INIS)

Mahoney, J.

1989-10-01

Highlights of the low energy research program included the identification of new super-deformed bands in gadolinium and palladium isotopes using the HERA array. Other work at the 88-Inch Cyclotron involved studies of the fragmentation of light nuclei; the spectroscopy of nuclear far from stability and interesting new experiments on the properties of the heaviest elements. Two other programs deserve special mention, the new program in Nuclear Astrophysics and the spectroscopic studies being carried out at OASIS. This isotope separator is now in full operation at the SuperHILAC after many yeas of development. At the Bevalac, important new results were obtained on the properties of hot dense nuclear matter produced in central collisions of heavy ions. First measurements were made using the di-lepton spectrometer which provide the most direct access to the conditions at the earliest stage of the reaction. New results on pion interferometry have been obtained using the Janus spectrometer and surprises continue to be found in careful analysis of data from the Plastic Ball detector, most recently the identification of a new component of hydrodynamic flow. Also at the Bevalac the intermediate energy program continued to grow, studying the evolution of the reaction mechanism from incomplete fusion to the fireball regime, as did the spectroscopic studies using secondary radioactive beams. The third major component of the experimental program is the study of ultra-relativistic nuclear collisions using the CERN SPS. This year saw the completing of analysis of the first round of experiments with important results being obtained on general particle production, the space-time evolution of the system and strangeness production

Nuclear Science Division annual report for the period October 1, 1987--September 30, 1988

Energy Technology Data Exchange (ETDEWEB)

Mahoney, J. (ed.)

1989-10-01

Highlights of the low energy research program included the identification of new super-deformed bands in gadolinium and palladium isotopes using the HERA array. Other work at the 88-Inch Cyclotron involved studies of the fragmentation of light nuclei; the spectroscopy of nuclear far from stability and interesting new experiments on the properties of the heaviest elements. Two other programs deserve special mention, the new program in Nuclear Astrophysics and the spectroscopic studies being carried out at OASIS. This isotope separator is now in full operation at the SuperHILAC after many yeas of development. At the Bevalac, important new results were obtained on the properties of hot dense nuclear matter produced in central collisions of heavy ions. First measurements were made using the di-lepton spectrometer which provide the most direct access to the conditions at the earliest stage of the reaction. New results on pion interferometry have been obtained using the Janus spectrometer and surprises continue to be found in careful analysis of data from the Plastic Ball detector, most recently the identification of a new component of hydrodynamic flow. Also at the Bevalac the intermediate energy program continued to grow, studying the evolution of the reaction mechanism from incomplete fusion to the fireball regime, as did the spectroscopic studies using secondary radioactive beams. The third major component of the experimental program is the study of ultra-relativistic nuclear collisions using the CERN SPS. This year saw the completing of analysis of the first round of experiments with important results being obtained on general particle production, the space-time evolution of the system and strangeness production.

Charged-particle multiplicity at mid-rapidity in Au–Au collisions at ...

Indian Academy of Sciences (India)

The particle density at mid-rapidity is an essential global variable for the characterization of nuclear collisions at ultra-relativistic energies. It provides information about the initial conditions and energy density reached in these collisions. The pseudorapidity densities of charged particles at mid-rapidity in Au + Au collisions at ...

On the Measurement of the Velocity of Light Emitted by an Ultrarelativistic Source

Science.gov (United States)

Kupryaev, N. V.

2015-01-01

By analytical calculations it has been shown that in papers on the measurement of the velocity of light published in 2011 in the journals Uspekhi Fizicheskikh Nauk [Physics-Uspekhi] and Pis'ma v ZhETF [JRTP Letters], in actual fact the velocity of a light pulse from a relativistic clot of electrons was not measured. All that was done was to compare the velocity of light emitted by an ultrarelativistic source with the velocity of light from a fixed source, i.e., both in the first and second variants (one independent quantity was compared with another), in essence, it was simply postulated. In the first variant a glass plate was used as the fixed light source, and in the second variants, a synchrotron pulse was used as the reference signal. The velocity of light was calculated using a calculated time based on the postulate of the special theory of relativity (STR) on the invariance of the velocity of light. This, of course, contradicts the Newton-Ritz hypothesis on ballistic addition of velocities, but at the present time this idea is not taken seriously. Practically none of the serious contemporary critics of STR, apart, of course, from amateurs, holds this point of view. The result cannot be considered as a direct experimental confirmation of the second postulate of Einstein's special theory of relativity, i.e., its main part, which speaks of the constancy of the velocity of light in all inertial reference frames, but only of that part which speaks of the independence of the velocity of light on motion of the source. Moreover, this same result stands as equal proof of the so-called theory of the luminiferous ether, which held sway up to the creation of the special theory of relativity and which has now been revived, i.e., it does not distinguish between these two theories. It is fundamentally impossible in principle to measure the velocity of light by the proposed method, it is only possible to postulate it.

The effect of pre-plasma formation under nonlocal transport conditions for ultra-relativistic laser-plasma interaction

Science.gov (United States)

Holec, M.; Nikl, J.; Vranic, M.; Weber, S.

2018-04-01

Interaction of high-power lasers with solid targets is in general strongly affected by the limited contrast available. The laser pre-pulse ionizes the target and produces a pre-plasma which can strongly modify the interaction of the main part of the laser pulse with the target. This is of particular importance for future experiments which will use laser intensities above 1021 W cm-2 and which are subject to the limited contrast. As a consequence the main part of the laser pulse will be modified while traversing the pre-plasma, interacting with it partially. A further complication arises from the fact that the interaction of a high-power pre-pulse with solid targets very often takes place under nonlocal transport conditions, i.e. the characteristic mean-free-path of the particles and photons is larger than the characteristic scale-lengths of density and temperature. The classical diffusion treatment of radiation and heat transport in the hydrodynamic model is then insufficient for the description of the pre-pulse physics. These phenomena also strongly modify the formation of the pre-plasma which in turn affects the propagation of the main laser pulse. In this paper nonlocal radiation-hydrodynamic simulations are carried out and serve as input for subsequent kinetic simulations of ultra-high intensity laser pulses interacting with the plasma in the ultra-relativistic regime. It is shown that the results of the kinetic simulations differ considerably whether a diffusive or nonlocal transport is used for the radiation-hydrodynamic simulations.

[Conduct theoretical and experimental research programs in high energy physics]: Technical progress, Appendix A-2, FTP/A, Item 20,f

International Nuclear Information System (INIS)

1986-01-01

Progress is reported in these areas: neutrino physics; nucleon decay and the intrinsic properties of neutrinos; the D-zero experiment; QCD jet physics and ultrarelativistic nuclear physics; the Colliding Detector at Fermilab; rare kaon decay; the Anomalous Single Photon detector at SLAC; particle theory; neutrino astrophysics and cosmology; and operations and support services

Signatures of quark-gluon plasma production

International Nuclear Information System (INIS)

Gyulassy, M.

1985-01-01

A critical analysis of a variety of proposed signatures for quark-gluon formation in ultrarelativistic nuclear collisions is given. The authors emphasize that longitudinal growth rather than the nuclear radius controls the time scales for expansion. The author pointed out the qualitative difference of the evolution of the plasma produced in the stopping regime E approx. 10 GeV/nucleon and the scaling regime E > 1 TeV/nucleon. This difference reflects itself in the the rmal profile function

Study of Υ family resonances in ultrarelativistic heavy ions collisions within the frame of the Alice experiment at CERN-LHC

International Nuclear Information System (INIS)

Dumonteil, E.

2004-09-01

Quantum Chromodynamics foresees, at high temperature and/or high energy density, a phase transition between hadronic matter and a phase where quarks and gluons are no more confined in the nucleons: the Quark Gluon Plasma (QGP). During the past fifteen years, a large experimental program has taken place at CERN and at BNL, to identify the QGP. ALICE is the LHC experiment dedicated to the study of the plasma via ultrarelativistic heavy ion collisions at 2.75 TeV/nucleon per beam. The measure of Upsilon's resonances suppression, a powerful signature of a deconfined medium, with the ALICE dimuon spectrometer, is the main topic of this thesis. The first part of the work aims at studying the multi-wires pad chambers of the dimuon arm, used to track the muons from resonances decays. The second part presents an in-beam alignment algorithm able to calculate the positions of the different chambers with a very good accuracy. Finally, the last part proposes a study to lead with the ALICE muon spectrometer, involving the measure of Upsilon and Upsilon's production ratio as a function of the transverse momentum. It has been showed that this study should allow to evidence the QGP and to extract some of its properties. (author)

Étude de la production de saveurs lourdes et de la multiplicité de particules chargées dans le cadre du formalisme du Color Glass Condensate pour les collisions p+p et p+Pb dans l'expérience ALICE au LHC

CERN Document Server

Malek, M

The classical nuclear matter is characterized by an energy density of the order of " = 0.17 GeV/fm3. For the critical values of the energy density (5 -10 ") or the temperature (150 - 200 MeV), the Lattice QuantumChromo Dynamics (LQCD) calculations predict a phase transition from the classical to a new form of nuclear matter called the Quark Gluon Plasma (QGP) in which quarks and gluons are deconfined. Heavy ion collisions allow to create the thermodynamical conditions needed for the QGP formation. The LHC will collide p+p and Pb+Pb nuclei at ultrarelativistic energies, reaching a few TeV per nucleon. At such ultra-relativistic energies, new theoretical approaches of QCD developed to understand high energy hadronic collisions can be tested experimentally. One of the most discussed topic is the Color Glass Condensate (CGC) approach allowing the description of the initial conditions of the heavy ion collision. The CGC approach predicts the saturation of the parton density of the nucleus for small values of the B...

Introduction to Chiral Symmetry

Energy Technology Data Exchange (ETDEWEB)

Koch, Volker [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-05-09

These lectures are an attempt to a pedagogical introduction into the elementary concepts of chiral symmetry in nuclear physics. We will also discuss some effective chiral models such as the linear and nonlinear sigma model as well as the essential ideas of chiral perturbation theory. We will present some applications to the physics of ultrarelativistic heavy ion collisionsd.

Introduction to chiral symmetry

International Nuclear Information System (INIS)

Koch, V.

1996-01-01

These lectures are an attempt to a pedagogical introduction into the elementary concepts of chiral symmetry in nuclear physics. Effective chiral models such as the linear and nonlinear sigma model will be discussed as well as the essential ideas of chiral perturbation theory. Some applications to the physics of ultrarelativistic heavy ion collisions will be presented

Heavy ions: Report from Relativistic Heavy Ion Collider

Indian Academy of Sciences (India)

2012-10-12

Oct 12, 2012 ... Experiments using ultrarelativistic heavy-ion collisions study nuclear matter under ... sN N = 10 GeV for Pb+Pb collisions, corresponding to an initial .... quenching through systematic comparisons of data to models, and .... the RdAu and RCP = (0−20%)/(60−80%) factors for the J/ψ production in d+Au col-.

The Mesozoic Era of relativistic heavy ion physics and beyond

International Nuclear Information System (INIS)

Harris, J.W.

1994-03-01

In order to understand how matter 15 billion years ago in the form of quarks, gluons and leptons at a temperature of 2 x 10 12 degrees K evolved to become today's Universe, the goal of relativistic and ultra-relativistic heavy ion physics is to understand the equation of state of nuclear, hadronic and partonic matter. This quest is of cross-disciplinary interest. The phase transition from partonic matter to hadronic matter tens of micro-seconds after the beginning of the universe is of interest to cosmology. Fluctuations during this phase transition would influence nucleosynthesis and the understanding of baryonic inhomogeneities in the universe. The nuclear matter equation of state, which describes the incompressibility of nuclear matter, governs neutron star stability. It determines the possible existence of strange quark matter stars and the dynamics of supernova expansion in astrophysics. The existence of collective nuclear phenomena in nuclear physics is also determined by the nuclear equation of state. In relativistic heavy ion collisions collective nuclear flow has been observed and is being studied extensively to obtain a better understanding of the incompressibility of nuclear matter. In high energy nuclear and particle physics, production and excitations of hadronic final states have been studied in detail and are important to an overall understanding of the equation of state of nuclear matter at finite temperature. The possibility in ultra-relativistic heavy ion collisions to create and study highly excited hadronic and partonic degrees of freedom provides a unique opportunity for understanding the behavior of nuclear, hadronic and partonic matter. Study of the QCD vacuum, of particular interest in particle physics, would provide a better understanding of symmetry-breaking mechanisms and the origins of the masses of the various quarks and particles

Nuclear interactions and hadronic matter

International Nuclear Information System (INIS)

Petrovici, Mihai; Pop, Amalia; Stoicea, Gabriel; Berceanu, Ionela; Moisa, Dorin; Petris, Mariana; Simion, Victor; Aiftimiei, Cristina; Cruceru, Ilie; Ciobanu, Mircea; Catanescu, Vasile; Caragheorgheopol; Gheorghe

2002-01-01

The new generation of heavy ion accelerators and complex experimental devices, developed in the last two decades, give access to new information concerning the dynamics of nuclear collisions and allow to obtain and study in the laboratory the nuclear matter under extreme conditions of density and temperature. Of special interest is the intermediate energy region where the reactions are dominated by the competition between the mean field and nucleon-nucleon interaction. Fundamental aspects of nuclear reaction studies are probed at different instants of a nuclear collision. One can learn about the transport properties of nuclear matter in pure nucleonic regime and understand the modification of the nucleon-nucleon cross section due to various in-medium effects: density effects, effective mass, quantum effects, three-body interactions. With increasing energy, fast particle emission associated with direct nucleon-nucleon collisions in the first steps of the reaction come into play too. At higher energy, flow measurements are crucial tests of the influence of medium effects by probing the elastic part of the nucleon-nucleon collisions. On the other side, at higher incident energies, the characteristics of the nuclear equation of state (EoS) can be studied if local thermal and chemical equilibrium turns out to be established. Understanding of the properties of the nuclear matter in extreme conditions is a fundamental goal. The EoS is also an essential ingredient in the description of the massive stars leading to supernova explosion and neutron star formation. Experimental studies of such aspects needs experimental devices of high complexity which can detect and identify event by event all products coming out from heavy ion interactions at intermediate, relativistic and ultra-relativistic energies, having as complete as possible information on their mass, charge, velocity vector. CHIMERA and FOPI are such devices for intermediate and relativistic energy, respectively. Our

Strangeness production in Au(1.23A GeV)+Au collisions

Czech Academy of Sciences Publication Activity Database

Schuldes, H.; Chlad, Lukáš; Kugler, Andrej; Rodriguez Ramos, Pablo; Sobolev, Yuri, G.; Svoboda, Ondřej; Tlustý, Pavel; Wagner, Vladimír

2017-01-01

Roč. 967, č. 11 (2017), s. 804-807 ISSN 0375-9474. [26th International Conference on Ultrarelativistic Nucleus-Nucleus Collissions (Quark Matter). Chicago, 05.02.2017-11.02.2017] R&D Projects: GA ČR GA13-06759S; GA MŠk LM2015049; GA MŠk EF16_013/0001677 Institutional support: RVO:61389005 Keywords : strangeness * sub-treshold * centrality dependence Subject RIV: BG - Nuclear , Atomic and Molecular Physics, Colliders OBOR OECD: Nuclear physics Impact factor: 1.916, year: 2016

Overview of recent results from HADES

Czech Academy of Sciences Publication Activity Database

Lorenz, M.; Chlad, Lukáš; Kugler, Andrej; Rodriguez Ramos, Pablo; Sobolev, Yuri, G.; Svoboda, Ondřej; Tlustý, Pavel; Wagner, Vladimír

2017-01-01

Roč. 967, č. 11 (2017), s. 27-34 ISSN 0375-9474. [26th International Conference on Ultrarelativistic Nucleus-Nucleus Collissions (Quark Matter). Chicago, 05.02.2017-11.02.2017] R&D Projects: GA MŠk EF16_013/0001677; GA ČR GA13-06759S; GA MŠk LM2015049 Institutional support: RVO:61389005 Keywords : HADES * QCD-phase diagram * high mu(B) Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders OBOR OECD: Nuclear physics Impact factor: 1.916, year: 2016

Collective flow measurements with HADES in Au plus Au collisions at 1.23A GeV

Czech Academy of Sciences Publication Activity Database

Kardan, B.; Chlad, Lukáš; Kugler, Andrej; Rodriguez Ramos, Pablo; Sobolev, Yuri, G.; Svoboda, Ondřej; Tlustý, Pavel; Wagner, Vladimír

2017-01-01

Roč. 967, č. 11 (2017), s. 812-815 ISSN 0375-9474. [26th International Conference on Ultrarelativistic Nucleus-Nucleus Collissions (Quark Matter). Chicago, 05.02.2017-11.02.2017] R&D Projects: GA ČR GA13-06759S; GA MŠk LM2015049; GA MŠk EF16_013/0001677 Institutional support: RVO:61389005 Keywords : heavy ion collisions * proton flow * directed flow Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders OBOR OECD: Nuclear physics Impact factor: 1.916, year: 2016

“barbari noi / chiama la vostra europa”. il personaggio esotico quale ...

African Journals Online (AJOL)

User

... Jüngere, l'opéra comique di Claude Godard d'Aucourt de Sain-Juste per François ... un fraintendimento di tipo anticheggiante e probabilmente come tale venne sentito .... benedizione della morente che invita in extremis il padre adottivo ad.

Electromagnetic pair production in relativistic heavy-ion collisions

International Nuclear Information System (INIS)

Bottcher, C.; Strayer, M.R.

1988-01-01

We survey the production of electron, muon and tauon pairs in collisions between nuclei at ultra-relativistic energies. Such studies enhance our understanding of the role of the vacuum in field theory, and provide essential input for several experimental programs. A variety of models for the nuclear and nucleon form factors have been considered, revealing some degree of sensitivity to assumptions about sub-nuclear structure. We predict that the cross sections, even at high invariant masses and transverse momenta, are large on hadronic scales, and should act as useful probes of nuclear and nucleon form factors. 21 refs., 5 figs

Studies of nuclei under the extreme conditions of density, temperature, isospin asymmetry and the phase diagram of hadronic matter

Energy Technology Data Exchange (ETDEWEB)

Mekjian, Aram [Rutgers Univ., Piscataway, NJ (United States). Dept. of Physics and Astronomy

2016-10-18

The main emphasis of the entire project is on issues having to do with medium energy and ultra-relativistic energy and heavy ion collisions. A major goal of both theory and experiment is to study properties of hot dense nuclear matter under various extreme conditions and to map out the phase diagram in density or chemical potential and temperature. My studies in medium energy nuclear collisions focused on the liquid-gas phase transition and cluster yields from such transitions. Here I developed both the statistical model of nuclear multi-fragmentation and also a mean field theory.

Dynamical renormalization group approach to transport in ultrarelativistic plasmas: The electrical conductivity in high temperature QED

International Nuclear Information System (INIS)

Boyanovsky, Daniel; Vega, Hector J. de; Wang Shangyung

2003-01-01

The dc electrical conductivity of an ultrarelativistic QED plasma is studied in real time by implementing the dynamical renormalization group. The conductivity is obtained from the real-time dependence of a dissipative kernel closely related to the retarded photon polarization. Pinch singularities in the imaginary part of the polarization are manifest as secular terms that grow in time in the perturbative expansion of this kernel. The leading secular terms are studied explicitly and it is shown that they are insensitive to the anomalous damping of hard fermions as a result of a cancellation between self-energy and vertex corrections. The resummation of the secular terms via the dynamical renormalization group leads directly to a renormalization group equation in real time, which is the Boltzmann equation for the (gauge invariant) fermion distribution function. A direct correspondence between the perturbative expansion and the linearized Boltzmann equation is established, allowing a direct identification of the self-energy and vertex contributions to the collision term. We obtain a Fokker-Planck equation in momentum space that describes the dynamics of the departure from equilibrium to leading logarithmic order in the coupling. This equation determines that the transport time scale is given by t tr =24 π/e 4 T ln(1/e). The solution of the Fokker-Planck equation approaches asymptotically the steady-state solution as ∼e -t/(4.038...t tr ) . The steady-state solution leads to the conductivity σ=15.698 T/e 2 ln(1/e) to leading logarithmic order. We discuss the contributions beyond leading logarithms as well as beyond the Boltzmann equation. The dynamical renormalization group provides a link between linear response in quantum field theory and kinetic theory

Wee partons in large nuclei: From virtual dream to hard reality

International Nuclear Information System (INIS)

Venugopalan, R.

1995-01-01

We construct a weak coupling, many body theory to compute parton distributions in large nuclei for x much-lt A - 1/3 . The wee partons are highly coherent, non-Abelian Weizsaecker-Williams fields. Radiative corrections to the classical results axe discussed. The parton distributions for a single nucleus provide the initial conditions for the dynamical evolution of matter formed in ultrarelativistic nuclear collisions

Wee partons in large nuclei: from virtual dream to hard reality

International Nuclear Information System (INIS)

Venugopalan, R.

1995-01-01

We construct a weak coupling, many body theory to compute parton distributions in large nuclei for x -1/3 . The wee partons are highly coherent, non-Abelian Weizsaecker-Williams fields. Radiative corrections to the classical results are discussed. The parton distributions for a single nucleus provide the initial conditions for the dynamical evolution of matter formed in ultrarelativistic nuclear collisions. (orig.)

A Nuclear Physics Program at the ATLAS Experiment at the CERN Large Hadron Collider

CERN Document Server

Aronson, S H; Gordon, H; Leite, M; Le Vine, M J; Nevski, P; Takai, H; White, S; Cole, B; Nagle, J L

2002-01-01

The ATLAS collaboration has significant interest in the physics of ultra-relativistic heavy ion collisions. We submitted a Letter of Intent to the United States Department of Energy in March 2002. The following document is a slightly modified version of that LOI. More details are available at: http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/SM/ions

Riemann problems and their application to ultra-relativistic heavy ion collisions

International Nuclear Information System (INIS)

Plohr, B.J.; Sharp, D.H.

1986-07-01

Heavy ion collisions at sufficiently high energies to form quark-gluon plasma are considered. The phase transformation from a quark-gluon phase to hadrons as the nuclear matter cools is modeled as a hydrodynamical flow. Nonlinear waves are the predominant feature of this type of flow and the Riemann problem of a relativistic gas undergoing a phase transformation is explored as a method to numerically model this phase transition process in nuclear matter. The solution of the Riemann problem is outlined and results of preliminary numerical computations of the flow are presented. 10 refs., 2 figs

Outcomes for cervicomediastinal vascular trauma managed by a ...

African Journals Online (AJOL)

Management was multimodal, and included conservative (8%), stenting and embolisation (8%), referral to a higher centre (8%), vascular repair (64%) and ligation (12%). Nineteen per cent required median sternotomy or thoracotomy. Eight patients died postoperatively (9%). Seven of them presented in extremis and died ...

Study of the transverse mass spectra of strange particles in Pb-Pb collisions at 158 A GeV/c

Czech Academy of Sciences Publication Activity Database

Antinori, F.; Bacon, P. A.; Badala, A.; Staroba, Pavel; Závada, Petr

2004-01-01

Roč. 30, - (2004), s. 823-840 ISSN 0954-3899 R&D Projects: GA AV ČR KSK1048102 Keywords : NA57 experiment * K o s, .XI. and .OMEGA. hyperons * Pb-Pb collisions at 158 A GeV/c * ultrarelativistic heavy-ion collisions * transverse mass spectra * excited nuclear matter * phase transition Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 1.533, year: 2004

PREFACE: XXXIII Symposium on Nuclear Physics

Science.gov (United States)

Barrón-Palos, Libertad; Bijker, Roelof; Fossion, Ruben; Lizcano, David

2010-04-01

physics, ranging from the traditional fields of nuclear structure and reactions to radioactive beams, nuclear astrophysics, hadronic physics, fundamental symmetries, ultrarelativistic heavy ions, cosmic rays and quantum chaos. The high quality of the talks, the prestige of the speakers and the broad spectrum of subjects covered in the meeting, shows that nuclear physics is a very active area at the frontier of scientific research which establishes bridges between many different disciplines. One of the exciting new areas in nuclear physics is that of radioactive beams. It provides a powerful tool not only to study exotic nuclei close to the proton and neutron drip lines to obtain important information about the nature of the nucleon-nucleon interaction in stable and unstable nuclei, but also to address questions of fundamental importance in nuclear astrophysics as well as in various applications like mass spectroscopy, the production of radioactive isotopes and medical applications (Galindo-Uribarri). There was a presentation on the FRIB project which is currently under construction in the USA and its relevance for nuclear astrophysics and the limits of stability (Sherrill and Schatz) In the session on nuclear structure, there were several talks on the nucleon-nucleon interaction in nuclei close to the proton and neutron drip lines, like neutron-proton pairing in nuclei with an equal number of protons and neutrons (Pittel), and studies of stable and unstable neutron-rich nuclei near the closed shells N = 82 and N = 50 using (d, p) transfer reactions and Coulomb excitation by means of radioactive beams (Cizewski and Padilla-Rodal). There were several talks on the importance of reaction rates for the excitation of spin-isospin resonances (Sakai), massive star evolution (Klapp) and nuclear synthesis and stellar evolution (Rolfs). In another presentation, the importance of rare isotopes for astrophysical processes was highlighted (Schatz). In addition, there were discussions

Annual report of the Nuclear Physics Laboratory, University of Washington

International Nuclear Information System (INIS)

Snover, K.; Fulton, B.

1996-04-01

The Nuclear Physics Laboratory of the University of Washington has for over 40 years supported a broad program of experimental physics research. Some highlights of the research activities during the past year are given. Work continues at a rapid pace toward completion of the Sudbury Neutrino Observatory in January 1997. Following four years of planning and development, installation of the acrylic vessel began last July and is now 50% complete, with final completion scheduled for September. The Russian-American Gallium Experiment (SAGE) has completed a successful 51 Cr neutrino source experiment. The first data from 8 B decay have been taken in the Mass-8 CVC/Second Class Current study. The analysis of the measured barrier distributions for Ca-induced fission of prolate 192 Os and oblate 194 Pt has been completed. In a collaboration with a group from the Bhabha Atomic Research Centre they have shown that fission anisotropies at energies well above the barrier are not influenced by the mass asymmetry of the entrance channel relative to the Businaro-Gallone critical asymmetry. They also have preliminary evidence at higher bombarding energy that noncompound nucleus fission scales with the mean square angular momentum, in contrast to previous suggestions. The authors have measured proton and alpha particle emission spectra from the decay of A ∼ 200 compound nuclei at excitation energies of 50--100 MeV, and used these measurements to infer the nuclear temperature. The investigations of multiparticle Bose-Einstein interferometry have led to a new algorithm for putting Bose-Einstein and Coulomb correlations of up to 6th order into Monte Carlo simulations of ultra-relativistic collision events, and to a new fast algorithm for extracting event temperatures

[Studies of target fragmentation in intermediate energy, relativistic and ultra-relativistic nuclear collisions]. Nuclear chemistry progress report, August 1, 1990--August 1, 1991

Energy Technology Data Exchange (ETDEWEB)

Loveland, W.D.

1991-08-01

The work described herein is part of a project involving the study of low energy (< 10 MeV/A), intermediate energy (10--100 MeV/A) and relativistic (> 250 MeV/A) heavy ion reactions. In the low energy regime, we published a monograph on the properties of the heaviest elements and used that publication as a basis for making a set of ``best`` semi-empirical predictions of heavy element decay properties. The intermediate energy research effort focussed upon the completion of studies already begun and the initiation of a number of new experiments. In our study of a interaction of 21 MeV/nucleon {sup 129}Xe with {sup 197}Au, we compared the characteristics of the observed deep inelastic phenomena with various models of dissipative reactions and found significant discrepancies between observations and predictions. These discrepancies seemed to be caused by an improper treatment of pre-equilibrium in the early stages of the collision. In our study of the relativistic interaction of 400 MeV/nucleon {sup 12}C with {sup 197}Au, we reported the first direct physical measurement of the properties of the spallation residues from a nucleus-nucleus collision. We found the residue energies to be much lower than those predicted by the intranuclear cascade model, indicating some substantial modifications of that model are needed. But, we also found, indications of significant, non-zero values of the residue transverse momentum, a finding that calls into question the interpretation of a number of radiochemical recoil studies of the kinematics of high energy reactions. A program of performing numerical simulations of intermediate and high energy nuclear collisions using the QMD model was initiated.

Parton-hadron cascade approach at SPS and RHIC

Energy Technology Data Exchange (ETDEWEB)

Nara, Yasushi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1998-07-01

A parton-hadron cascade model which is the extension of hadronic cascade model incorporating hard partonic scattering based on HIJING is presented to describe the space-time evolution of parton/hadron system produced by ultra-relativistic nuclear collisions. Hadron yield, baryon stopping and transverse momentum distribution are calculated and compared with HIJING and VNI. Baryon density, energy density and temperature for RHIC are calculated within this model. (author)

Study of {upsilon} family resonances in ultrarelativistic heavy ions collisions within the frame of the Alice experiment at CERN-LHC; Etude des resonances de la famille du {upsilon} dans les collisions d'ions lourds ultra-relativistes a 2.75 TeV/ nucleon et par faisceau sur l'experience Alice du LHC

Energy Technology Data Exchange (ETDEWEB)

Dumonteil, E

2004-09-01

Quantum Chromodynamics foresees, at high temperature and/or high energy density, a phase transition between hadronic matter and a phase where quarks and gluons are no more confined in the nucleons: the Quark Gluon Plasma (QGP). During the past fifteen years, a large experimental program has taken place at CERN and at BNL, to identify the QGP. ALICE is the LHC experiment dedicated to the study of the plasma via ultrarelativistic heavy ion collisions at 2.75 TeV/nucleon per beam. The measure of Upsilon's resonances suppression, a powerful signature of a deconfined medium, with the ALICE dimuon spectrometer, is the main topic of this thesis. The first part of the work aims at studying the multi-wires pad chambers of the dimuon arm, used to track the muons from resonances decays. The second part presents an in-beam alignment algorithm able to calculate the positions of the different chambers with a very good accuracy. Finally, the last part proposes a study to lead with the ALICE muon spectrometer, involving the measure of Upsilon and Upsilon's production ratio as a function of the transverse momentum. It has been showed that this study should allow to evidence the QGP and to extract some of its properties. (author)

Low-mass dielectron production in Pb - Au collisions at 158 AGeV using the upgraded CERES spectrometer

CERN Document Server

Cherlin, Alexander

This thesis deals with the measurements and results of inclusive $e^{+}e^{-}$ pair production in ultra-relativistic Pb - Au collisions at 158 AGeV . The measurements were performed in the framework of the CERES experiment at the CERN SPS. The main aim for studying ultra-relativistic collisions of heavy ions is to investigate the behavior of nuclear matter under extreme conditions of density and temperature. Lattice QCD calculations predict that under conditions of suciently high temperature and/or baryon density the quark and gluon degrees of freedom, usually conned within hadrons, are liberated. This state of matter is called the Quark-Gluon Plasma (QGP). Another phenomenon associated with the QGP phase transition is the restoration of the spontaneously broken chiral symmetry. Lepton pairs are unique probes of the initial reball. Since they interact only electromagnetically, they have a long mean free path and can leave the interaction region without any additional interactions carrying direct information on...

Effects of the in-medium nucleon-nucleon cross section on collective flow and nuclear stopping in heavy-ion collisions in the Fermi-energy domain

Science.gov (United States)

Li, Pengcheng; Wang, Yongjia; Li, Qingfeng; Guo, Chenchen; Zhang, Hongfei

2018-04-01

With the newly updated version of the ultrarelativistic quantum molecular dynamics (UrQMD) model, a systematic investigation of the effects of in-medium nucleon-nucleon (NN ) elastic cross section on the collective flow and the stopping observables in 197Au+197Au collisions at beam energies from 40 to 150 MeV/nucleon is performed. Simulations with the medium correction factors F =σNN in -medium/σNN free=0.2 ,0.3 ,0.5 and the one obtained with the FU3FP1 parametrization which depends on both the density and the momentum are compared to the FOPI and INDRA experimental data. It is found that, to best fit the experimental data of the slope of the directed flow and the elliptic flow at midrapidity as well as the nuclear stopping, the correction factors of F =0.2 and 0.5 are required for reactions at beam energies of 40 and 150 MeV/nucleon, respectively. Whereas calculations with the FU3FP1 parametrization can simultaneously reproduce these experimental data reasonably well. And, the observed increasing nuclear stopping with increasing beam energy in experimental data can also be reproduced by using the FU3FP1 parametrization, whereas the calculated stopping power in Au + Au collisions with beam energies from 40 to 150 MeV /nucleon almost remains constant when taking F equal to a fixed value.

Hadronic and electromagnetic fragmentation of ultrarelativistic heavy ions at LHC

Czech Academy of Sciences Publication Activity Database

Braun, H.H.; Fasso, Alberto; Ferrari, A.; Jowett, J.M.; Sala, P.R.; Smirnov, G.I.

2014-01-01

Roč. 17, č. 2 (2014), "021006-1"-"021006-14" ISSN 1098-4402 R&D Projects: GA MŠk ED1.1.00/02.0061; GA MŠk EE2.3.20.0279 Grant - others:ELI Beamlines(XE) CZ.1.05/1.1.00/02.0061; LaserZdroj (OP VK 3)(XE) CZ.1.07/2.3.00/20.0279 Institutional support: RVO:68378271 Keywords : ions * accelerators * beams Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.661, year: 2014

Thoracic damage control surgery.

Science.gov (United States)

Gonçalves, Roberto; Saad, Roberto

2016-01-01

The damage control surgery came up with the philosophy of applying essential maneuvers to control bleeding and abdominal contamination in trauma patients who are within the limits of their physiological reserves. This concept was extended to thoracic injuries, where relatively simple maneuvers can shorten operative time of in extremis patients. This article aims to revise the various damage control techniques in thoracic organs that must be known to the surgeon engaged in emergency care. RESUMO A cirurgia de controle de danos surgiu com a filosofia de se aplicar manobras essenciais para controle de sangramento e contaminação abdominal, em doentes traumatizados, nos limites de suas reservas fisiológicas. Este conceito se estendeu para as lesões torácicas, onde manobras relativamente simples, podem abreviar o tempo operatório de doentes in extremis. Este artigo tem como objetivo, revisar as diversas técnicas de controle de dano em órgãos torácicos, que devem ser de conhecimento do cirurgião que atua na emergência.

Study of high energy densities over extended nuclear volumes via nucleus-nucleus collisions at the SPS

CERN Multimedia

2002-01-01

This experiment examines in detail the characteristics of ultra-relativistic nucleus-nucleus interactions using $^{16}$O beams of 200 GeV/A from the SPS. The experiment combines 4$\\pi$ calorimeter coverage with measurements of inclusive particle spectra, two-particle correlations, low and high-mass lepton pairs and photons. A multiwire active target allows maximum interaction rates with a minimum of secondary interactions. Additional data are taken with an emulsion target.

Formation of heavy quarks in ultrarelativistic heavy-ion collisions

International Nuclear Information System (INIS)

Schneider, S.M.; Greiner, W.; Soff, G.

1992-02-01

We investigate the production of heavy quarks in continuum and bound states in nuclear collisions. Creation for free banti b and tanti t quark pairs and for bottomonium and toponium in the ground state are computed at RHIC, LHC and SSC energies. Central and peripheral heavy-ion collisions are discussed. For top quark creation we assumed a mass range of 90 GeV ≤ m t ≤ 250 GeV. The creation rate for top quarks on peripheral collisions is estimated to be by a factor 40 to 130 smaller compared with corresponding central collisions. For m t = 130 GeV we calculated a creation rate of about 4760 top quark pairs per day at the LHC (3.5 TeV/u) for Pb-Pb collisions. (orig.)

Low-mass e(+)e(-) mass distributions from 1.23A GeV Au plus Au collisions with HADES

Czech Academy of Sciences Publication Activity Database

Galatyuk, T.; Chlad, Lukáš; Kugler, Andrej; Rodriguez Ramos, Pablo; Sobolev, Yuri, G.; Svoboda, Ondřej; Tlustý, Pavel; Wagner, Vladimír

2017-01-01

Roč. 967, č. 11 (2017), s. 680-683 ISSN 0375-9474. [26th International Conference on Ultrarelativistic Nucleus-Nucleus Collissions (Quark Matter). Chicago, 05.02.2017-11.02.2017] R&D Projects: GA MŠk EF16_013/0001677; GA ČR GA13-06759S; GA MŠk LM2015049 Institutional support: RVO:61389005 Keywords : HADES * dielectrons Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders OBOR OECD: '' Impact factor: 1.916, year: 2016

Z and W boson production in pPb collisions with CMS

CERN Document Server

Zsigmond, Anna Julia

2014-01-01

The electroweak boson production is an important benchmark measurement in ultra-relativistic heavy-ion collisions which can provide constraints on the nuclear parton distribution functions. In this paper the first results from the proton-lead collision data taken in early 2013 are presented. The Z boson production cross section is measured in the muon decay channel in bins of transverse momentum and rapidity together with the forward-backward ratio. The W production is studied in the muon and electron decay channels and the differential cross sections, lepton-charge and forward-backward asymmetries are computed as a function of the lepton pseudorapidity. All results are compared with theory predictions with and without nuclear modification of the parton distribution functions showing hints of nuclear effects.

Semianalytical study of the propagation of an ultrastrong femtosecond laser pulse in a plasma with ultrarelativistic electron jitter

Energy Technology Data Exchange (ETDEWEB)

Jovanović, Dušan, E-mail: dusan.jovanovic@ipb.ac.rs [Institute of Physics, University of Belgrade, Pregrevica 118, 11080 Belgrade, Zemun (Serbia); Fedele, Renato, E-mail: renato.fedele@na.infn.it [Dipartimento di Fisica, Università di Napoli “Federico II,” M.S. Angelo, Napoli (Italy); INFN Sezione di Napoli, Complesso Universitario di M.S. Angelo, Napoli (Italy); Belić, Milivoj, E-mail: milivoj.belic@qatar.tamu.edu [Texas A and M University at Qatar, P.O. Box 23874, Doha (Qatar); De Nicola, Sergio, E-mail: sergio.denicola@spin.cnr.it [SPIN-CNR, Complesso Universitario di M.S. Angelo, Napoli (Italy)

2015-04-15

The interaction of a multi-petawatt, pancake-shaped laser pulse with an unmagnetized plasma is studied analytically and numerically in a regime with ultrarelativistic electron jitter velocities, in which the plasma electrons are almost completely expelled from the pulse region. The study is applied to a laser wakefield acceleration scheme with specifications that may be available in the next generation of Ti:Sa lasers and with the use of recently developed pulse compression techniques. A set of novel nonlinear equations is derived using a three-timescale description, with an intermediate timescale associated with the nonlinear phase of the electromagnetic wave and with the spatial bending of its wave front. They describe, on an equal footing, both the strong and the moderate laser intensity regimes, pertinent to the core and to the edges of the pulse. These have fundamentally different dispersive properties since in the core the electrons are almost completely expelled by a very strong ponderomotive force, and the electromagnetic wave packet is imbedded in a vacuum channel, thus having (almost) linear properties. Conversely, at the pulse edges, the laser amplitude is smaller, and the wave is weakly nonlinear and dispersive. New nonlinear terms in the wave equation, introduced by the nonlinear phase, describe without the violation of imposed scaling laws a smooth transition to a nondispersive electromagnetic wave at very large intensities and a simultaneous saturation of the (initially cubic) nonlocal nonlinearity. The temporal evolution of the laser pulse is studied both analytically and by numerically solving the model equations in a two-dimensional geometry, with the spot diameter presently used in some laser acceleration experiments. The most stable initial pulse length is estimated to exceed ≳1.5–2 μm. Moderate stretching of the pulse in the direction of propagation is observed, followed by the development of a vacuum channel and of a very large

Physics Division progress report for period ending September 30, 1990

International Nuclear Information System (INIS)

Livingston, A.B.

1991-03-01

The activities of this Division continue to be concentrated in the areas of experimental nuclear physics, experimental atomic physics, and theoretical nuclear and atomic physics. The Holifield Heavy Ion Research Facility and its operation as a national user facility continued as the single largest activity within the Division. The experimental nuclear physics program continues to emphasize heavy ion studies, with much of the activity centered at the Holifield Facility. The work with heavy ions at ultrarelativistic energies continues at the CERN SPS. Studies at the Brookhaven AGS, particularly in preparation of future experiments at RHIC, have seen an increased emphasis. A major consortium has been formed to propose the design and construction of a dimuon detector as the basis for one the principal experiments for RHIC. Also included are results from the increasing effort in particle physics, including participation in the L* proposal for the SSC. The UNISOR program, since its inception, has been associated intimately with the Division and, most particularly, with the Holifield Facility. A major area of experimental research for the Division is atomic physics. This activity comprises two groups: one on accelerator-based atomic physics, centered primarily at the EN-tandem and the Holifield Facility, but extending this year to an experiment at ultrarelativistic energies at the CERN SPS; and one on atomic physics in support of fusion energy, based primarily at the ECR ion source facility. Included in this section is also a description of a new effort in multicharged ion-surface interactions, and details of a planned upgrade of the ECR source

Physics Division progress report for period ending September 30, 1990

Energy Technology Data Exchange (ETDEWEB)

Livingston, A.B. (ed.)

1991-03-01

The activities of this Division continue to be concentrated in the areas of experimental nuclear physics, experimental atomic physics, and theoretical nuclear and atomic physics. The Holifield Heavy Ion Research Facility and its operation as a national user facility continued as the single largest activity within the Division. The experimental nuclear physics program continues to emphasize heavy ion studies, with much of the activity centered at the Holifield Facility. The work with heavy ions at ultrarelativistic energies continues at the CERN SPS. Studies at the Brookhaven AGS, particularly in preparation of future experiments at RHIC, have seen an increased emphasis. A major consortium has been formed to propose the design and construction of a dimuon detector as the basis for one the principal experiments for RHIC. Also included are results from the increasing effort in particle physics, including participation in the L* proposal for the SSC. The UNISOR program, since its inception, has been associated intimately with the Division and, most particularly, with the Holifield Facility. A major area of experimental research for the Division is atomic physics. This activity comprises two groups: one on accelerator-based atomic physics, centered primarily at the EN-tandem and the Holifield Facility, but extending this year to an experiment at ultrarelativistic energies at the CERN SPS; and one on atomic physics in support of fusion energy, based primarily at the ECR ion source facility. Included in this section is also a description of a new effort in multicharged ion-surface interactions, and details of a planned upgrade of the ECR source.

The Alice experiment for the study of ultra relativistic heavy ion collisions; Experience ALICE pour l'etude des collisions d'ions lourds ultra-relativistes au CERN-LHC

Energy Technology Data Exchange (ETDEWEB)

Forestier, B

2003-12-01

Alice is the detector dedicated to the study of heavy ions at the LHC (large hadron collider). It will allow scientists to investigate all the signatures of quark-gluon plasma (QGP). The spectrometer of the dimuon arm of Alice has been designed to study the production of high mass resonances through their dimuon decay. The first chapter is dedicated to some aspects of the physics of ultra-relativistic heavy ion: confinement and de-confinement of quarks, the absence of heavy resonances as a signature for the presence of QGP. The second chapter presents Alice and its ancillary detectors. The third chapter deals with the trigger system of the dimuon spectrometer, a detailed algorithm of this system is given. A method for the optimization of the trigger response is presented in the fourth chapter. The fifth chapter describes the testing of a prototype of the trigger system, this testing with muons has shown that the efficiency of the track reconstruction of the trigger system and the efficiency of the resistive plate chamber reach 98%.In the sixth chapter the author comments the simulations of the production of heavy resonances from Pb-Pb collisions as a function of centrality. (A.C.)

Transverse expansion and dileptons from the rho-peak in ultrarelativistic nuclear collisions

International Nuclear Information System (INIS)

Fai, G.; Neumann, J.J.; Seibert, D.

1995-01-01

The authors calculate the transverse-mass distribution of lepton pairs in the ρ - ω peak. An equation of state with a strong first order phase transition is assumed. They focus on the baryon-free central rapidity region, and couple a boost-invariant longitudinal expansion to a cylindrically symmetric transverse expansion to model the dynamics of central collisions. In the absence of transverse expansion, the fit temperature of the resulting dilepton spectra provided a good thermometer for the critical temperature. Assuming thermal equilibrium throughout the collision, they study the effect of transverse expansion on the spectra. They allow deviations from chemical equilibrium in the high-temperature phase by appropriately parametrizing the equation of state. The freeze-out dependence is also studied. They calculate dilepton production vs. transverse-mass as a function of the critical temperature for these different scenarios

On the possibility of thermalization of heavy mesons in ultrarelativistic nuclear collisions

Energy Technology Data Exchange (ETDEWEB)

Lokhtin, I. P., E-mail: Igor.Lokhtin@cern.ch; Belyaev, A. V. [Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation); Ponimatkin, G. [Czech Technical University in Prague, Faculty of Nuclear Sciences and Physical Engineering (Czech Republic); Pronina, E. Yu.; Eiyubova, G. Kh. [Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation)

2017-02-15

The phenomenological analysis and interpretation of experimental data from RHIC and LHC on the production of J/ψ and D mesons in heavy-ion collisions are performed within the two-component HYDJET++ model including the thermal and hard mechanisms of hadron production. It is shown that the thermal freeze-out of charmed mesons at RHIC energies occurs earlier than the thermal freeze-out of light hadrons (assumingly, simultaneously with chemical freeze-out), which indicates that J/ψ and D mesons are not in kinetic equilibrium with the formed hadronic matter. At the same time, a significant part of D mesons at LHC energies are in kinetic equilibrium with the formed thermalized matter, but J/ψ mesons are still characterized by early freeze-out.

Heavy ions

CERN Multimedia

CERN. Geneva; Antinori, Federico

2001-01-01

Colliding two heavy nuclei at ultrarelativistic energies allows to create in the laboratory a bulk system with huge density, pressure and temperature and to study its properties. It is estimated that in Pb-Pb collisions at CERN-SPS we reach over an appreciable volume an energy density which exceeds by more than a factor 20 that of normal nuclear matter. At such densities, the hadrons are so closely packed that they interpenetrate; novel physics phenomena are expected to appear. QCD predicts that under such conditions a phase transition from a system composed of colourless hadrons to a Quark-Gluon Plasma (QGP) should occur. A rich ultrarelativistic heavy-ion physics programme is under way both at BNL-AGS and at CERN-SPS since 1986. The results obtained so far have led CERN to officially announce evidence for a new state of matter last year. A long-range programme of heavy-ion physics at higher energies is under way (BNL-RHIC) and in preparation (CERN-LHC). These lectures are meant as an introduction to the phy...

Heavy ions

CERN Multimedia

CERN. Geneva. Audiovisual Unit

2002-01-01

Colliding two heavy nuclei at ultrarelativistic energies allows to create in the laboratory a bulk system with huge density, pressure and temperature and to study its properties. It is estimated that in Pb-Pb collisions at CERN-SPS we reach over an appreciable volume an energy density which exceeds by more than a factor 20 that of normal nuclear matter. At such densities, the hadrons are so closely packed that they interpenetrate; novel physics phenomena are expected to appear. QCD predicts that under such conditions a phase transition from a system composed of colourless hadrons to a Quark-Gluon Plasma (QGP) should occur. A rich ultrarelativistic heavy-ion physics programme is under way both at BNL-AGS and at CERN-SPS since 1986. The results obtained so far have led CERN to officially announce evidence for a new state of matter last year. A long-range programme of heavy-ion physics at higher energies is under way (BNL-RHIC) and in preparation (CERN-LHC). These lectures are meant as an introduction to the phy...

Electron-positron pair production in Coulomb collisions at ultrarelativistic energies

International Nuclear Information System (INIS)

Vane, C.R.; Datz, S.; Dittner, P.F.; Krause, H.F.; Bottcher, C.; Strayer, M.; Schuch, R.; Gao, H.; Hutton, R.

1993-01-01

We have measured angular and momentum distributions for electrons and positrons created as pairs in peripheral collisions of 6.4 TeV bare sulfur ions with fixed targets of Al, Pd, and Au. Singly- and doubly-differential cross sections have been determined for 1--17 MeV/c electrons and positrons detected independently and in coincidence as pairs. Integrated yields for pair production are found to vary as the square of the target nuclear charge. Relative angular and momentum differential cross sections are effectively target independent. Probability distributions for the pair total momentum, the positron fraction of the pair momentum, and the pair traverse momentum have been derived from the coincident electron-positron data

Blueprint for Implementing New Processes in Acute Care: Rescuing Adult Patients With Intraosseous Access.

Science.gov (United States)

Chreiman, Kristen M; Kim, Patrick K; Garbovsky, Lyudmila A; Schweickert, William D

2015-01-01

The intraosseous (IO) access initiative at an urban university adult level 1 trauma center began from the need for a more expeditious vascular access route to rescue patients in extremis. The goal of this project was a multidisciplinary approach to problem solving to increase access of IO catheters to rescue patients in all care areas. The initiative became a collaborative effort between nursing, physicians, and pharmacy to embark on an acute care endeavor to standardize IO access. This is a descriptive analysis of processes to effectively develop collaborative strategies to navigate hospital systems and successfully implement multilayered initiatives. Administration should empower nurse to advance their practice to include IO for patient rescue. Intraosseous access may expedite resuscitative efforts in patients in extremis who lack venous access or where additional venous access is required for life-saving therapies. Limiting IO dwell time may facilitate timely definitive venous access. Continued education and training by offering IO skill laboratory refreshers and annual e-learning didactic is optimal for maintaining proficiency and knowledge. More research opportunities exist to determine medication safety and efficacy in adult patients in the acute care setting.

Determination of the nuclear incompressibility from the rapidity-dependent elliptic flow in heavy-ion collisions at beam energies 0.4A–1.0A GeV

Directory of Open Access Journals (Sweden)

Yongjia Wang

2018-03-01

Full Text Available Background: The nuclear incompressibility (K0 plays a crucial role in understanding diverse phenomena in nuclear structure and reactions, as well as in astrophysics. Heavy-ion-collision measurements in combination with transport model simulations serve as important tools for extracting the nuclear incompressibility. However, uncertainties in transport models (or model dependence partly affect the reliability of the extracted result. Purpose: In the present work, by using the recently measured data of rapidity-dependent flows, we constrain the incompressibility of nuclear matter and analyze the impact of model uncertainties on the obtained value. Method: The method is based on the newly updated version of the ultrarelativistic quantum molecular dynamics (UrQMD model in which the Skyrme potential energy-density functional is introduced. Three different Skyrme interactions which give different incompressibilities varying from K0=201 to 271 MeV are adopted. The incompressibility is deduced from the comparison of the UrQMD model simulations and the FOPI data for rapidity-dependent elliptic flow in Au+Au collisions at beam energies 0.4A–1.0A GeV. Results: The elliptic flow v2 as a function of rapidity y0 can be well described by a quadratic fit v2=v20+v22⋅y02. It is found that the quantity v2n defined by v2n=|v20|+|v22| is quite sensitive to the incompressibility K0 and the in-medium nucleon–nucleon cross section, but not sensitive to the slope parameter L of the nuclear symmetry energy. Conclusions: With the FU3FP4 parametrization of the in-medium nucleon–nucleon cross section, an averaged K0=220±40 MeV is extracted from the v2n of free protons and deuterons. However, remaining systematic uncertainties, partly related to the choice of in-medium nucleon–nucleon cross sections, are of the same magnitude (±40 MeV. Overall, the rapidity dependent elliptic flow supports a soft symmetric-matter equation-of-state.

Determination of the nuclear incompressibility from the rapidity-dependent elliptic flow in heavy-ion collisions at beam energies 0.4A-1.0A GeV

Science.gov (United States)

Wang, Yongjia; Guo, Chenchen; Li, Qingfeng; Le Fèvre, Arnaud; Leifels, Yvonne; Trautmann, Wolfgang

2018-03-01

Background: The nuclear incompressibility (K0) plays a crucial role in understanding diverse phenomena in nuclear structure and reactions, as well as in astrophysics. Heavy-ion-collision measurements in combination with transport model simulations serve as important tools for extracting the nuclear incompressibility. However, uncertainties in transport models (or model dependence) partly affect the reliability of the extracted result. Purpose: In the present work, by using the recently measured data of rapidity-dependent flows, we constrain the incompressibility of nuclear matter and analyze the impact of model uncertainties on the obtained value. Method: The method is based on the newly updated version of the ultrarelativistic quantum molecular dynamics (UrQMD) model in which the Skyrme potential energy-density functional is introduced. Three different Skyrme interactions which give different incompressibilities varying from K0 = 201 to 271 MeV are adopted. The incompressibility is deduced from the comparison of the UrQMD model simulations and the FOPI data for rapidity-dependent elliptic flow in Au + Au collisions at beam energies 0.4A-1.0A GeV. Results: The elliptic flow v2 as a function of rapidity y0 can be well described by a quadratic fit v2 =v20 +v22 ṡ y02 . It is found that the quantity v2n defined by v2n = |v20 | + |v22 | is quite sensitive to the incompressibility K0 and the in-medium nucleon-nucleon cross section, but not sensitive to the slope parameter L of the nuclear symmetry energy. Conclusions: With the FU3FP4 parametrization of the in-medium nucleon-nucleon cross section, an averaged K0 = 220 ± 40 MeV is extracted from the v2n of free protons and deuterons. However, remaining systematic uncertainties, partly related to the choice of in-medium nucleon-nucleon cross sections, are of the same magnitude (± 40 MeV). Overall, the rapidity dependent elliptic flow supports a soft symmetric-matter equation-of-state.

Single- and double-scattering production of four muons in ultraperipheral PbPb collisions at the Large Hadron Collider

Directory of Open Access Journals (Sweden)

Andreas van Hameren

2018-01-01

Full Text Available We discuss production of two μ+μ− pairs in ultraperipheral ultrarelativistic heavy ion collisions at the LHC. We take into account electromagnetic (two-photon double-scattering production and for a first time direct γγ production of four muons in one scattering. We study the unexplored process γγ→μ+μ−μ+μ−. We present predictions for total and differential cross sections. Measurable nuclear cross sections are obtained and corresponding differential distributions and counting rates are presented.

An introduction to quark-gluon plasma and high energy heavy ion collisions

International Nuclear Information System (INIS)

McLerran, L.

1987-01-01

The quark-gluon plasma, and how it might be produced in ultra-relativistic nuclear collisions is reviewed. I briefly introduce the quark-gluon plasma, and what we might learn from studying it. I then discuss what has been learned from the recent results from the CERN oxygen run. I then attempt to address the issue of whether A = 16 and E = 200 GeV are sufficient to make a quark-gluon plasma. I discuss strangeness and charm production as well as electromagnetic probes of the plasma

arXiv Measurement of the D-meson nuclear modification factor and elliptic flow in Pb-Pb collisions at $\\sqrt{s_{\\text{{NN}}}}$ = 5.02 TeV with ALICE at the LHC

CERN Document Server

Jaelani, Syaefudin

2018-05-03

Heavy-flavour hadrons are effective probes to study the Quark-Gluon Plasma (QGP) formed in ultra-relativistic heavy-ion collisions. The ALICE Collaboration measured the D-mesons (D0, D+, D*+ and Ds+) production in Pb–Pb collisions at sNN = 5.02 TeV. The in-medium energy loss can be studied by means of the nuclear modification factor (RAA). The comparison between the Ds+ and the non-strange D-meson RAA can help to study the hadronisation mechanism of the charm quark in the QGP. In semi-central collisions the measurement of the D-meson elliptic flow, v2, at low pT allows to investigate the participation of the heavy quarks in the collective expansion of the system while at high pT it constrains the path-length dependence of the energy loss. Furthermore the Event-Shape Engineering (ESE) technique is used to measure D-meson elliptic flow in order to study the coupling of the charm quarks to the light quarks of the underlying medium.

Heavy nuclei, from RHIC to the cosmos

International Nuclear Information System (INIS)

Klein, Spencer R.

2003-01-01

Ultra-relativistic heavy ion collisions produce a high-temperature, thermalized system that may mimic the conditions present shortly after the big bang. This writeup will given an overview of early results from the Relativistic Heavy Ion Collider (RHIC), and discuss what we have learned about hot, strongly interacting nuclear systems. The thermal and chemical composition of the system will be discussed, along with observables that are sensitive to the early evolution of the system. I will also discuss the implications of the RHIC results for cosmic ray air showers

Study of Z boson production in the muon decay channel in pPb collisions at $\\sqrt{{s_{NN}}}=5.02$ TeV

CERN Document Server

CMS Collaboration

2014-01-01

The electroweak boson production is an important benchmark measurement in ultrarelativistic heavy-ion collisions which can provide constraints on the nuclear modification of parton distribution functions. In this paper the results from the proton-lead collision data taken in early 2013 are presented. The Z boson production cross section is measured in bins of the Z boson rapidity and transverse momentum and compared to theoretical predictions. The Z boson production is observed to be proportional to the number of elementary nucleon-nucleon collisions. The forward-backward ratio of the measured cross section is presented.

Hard processes and fragmentation in a unified model for interactions at ultra-relativistic energies; Les processus durs et la fragmentation dans un modele unifie pour les interactions aux energies ultra-relativistes

Energy Technology Data Exchange (ETDEWEB)

Drescher, H.J

1999-06-11

In this work we have developed hard processes and string fragmentation in the framework of interactions at relativistic energies. The hypothesis of the universality of high energy interactions means that many elements of heavy ion collisions can be studied and simulated in simpler nuclear reactions. In particular this hypothesis implies that the fragmentation observed in the reaction e{sup +}e{sup -} follows the same rules as in the collision of 2 lead ions. This work deals with 2 nuclear processes: the e{sup +}e{sup -} annihilation reaction and the deep inelastic diffusion. For the first process the string model has been developed to simulate fragmentation by adding an artificial breaking of string due to relativistic effects. A monte-Carlo method has been used to determine the points in a Minkowski space where this breaking occurs. For the second reaction, the theory of semi-hard pomerons is introduced in order to define elementary hadron-hadron interactions. The model of fragmentation proposed in this work can be applied to more complicated reactions such as proton-proton or ion-ion collisions.

Energy density, stopping and flow in ultrarelativistic heavy ion collisions

International Nuclear Information System (INIS)

Sorge, H.; von Keitz, A.; Mattiello, R.; Stoecker, H.; Greiner, W.

1990-01-01

The Lorentz invariant molecular dynamics approach (RQMD) is employed to investigate the space-time evolution of heavy ion collisions at energies (E kin = 10AGeV hor-ellipsis 200AGeV). The calculations for various nucleus nucleus reactions show a high degree of stopping power. The importance of secondary rescattering at these beam energies is demonstrated. The computed nucleon rapidity distributions are compared to available experimental data. It is demonstrated that nonlinear, collective effects like full stopping of target and projectile and matter flow could be expected for heavy projectiles only. For nuclear collisions in the Booster era at BNL and for the lead beam at CERN SPS the authors predict a stimulating future: then a nearly equilibrated, long lived (8 fm/c) macroscopic volume of very high energy density (> 1 GeV/fm 3 ) and baryon density (> 5 times ground state density) is produced

Diffusion constant in hot and dense hadronic matter. A hadro-molecular-dynamic calculation

International Nuclear Information System (INIS)

Sasaki, N.; Miyamura, O.; Muroya, S.; Nonaka, C.

2002-01-01

We evaluate baryon/charge diffusion constant of dense and hot hadronic matter based on the molecular dynamical method by using a hadronic collision generator which describes nuclear collisions at energies 10 1-2 GeV/A and satisfies detailed balance at low temperatures (T ≤ 200 MeV). For the hot and dense hadronic matter of the temperature range, T = 100 - 200 MeV and baryon number density, n B =0.16 fm -3 - 0.32 fm -3 , charge diffusion constant D gradually increases from 0.5 fmc to 2 fmc with temperature and is almost independent of baryon number density. Based on the obtained diffusion constant we make simple discussions on the diffusion of charge fluctuation in ultrarelativistic nuclear collisions. (author)

Oxygen induced reactions at 200 and 60 GeV/nucleon

International Nuclear Information System (INIS)

Gutbrod, H.H.; Albrecht, R.; Claesson, G.; Bock, R.; Kolb, B.W.; Lund, I.; Schmidt, H.R.; Siemiarczuk, T.; Awes, T.C.; Baktash, C.; Ferguson, R.L.; Johnson, J.W.; Lee, I.Y.; Obenshain, F.E.; Plasil, F.; Sorensen, S.P.; Young, G.R.

1988-01-01

The ultimate goal of ultra-relativistic heavy ion physics is the creation and detection of a new form of matter, the so-called Quark-Gluon Plasma (QGP). The QGP is a state of matter in which normal nuclear matter has been compressed to such an extent that the color force field between the constituents of the nucleon is sufficiently screened that a deconfinement phase transition takes place [Sa86]. It is widely believed that the early universe, some 10 -6 seconds after its creation, consisted of this form of primordial matter. This paper shows the space-time evolution of quark matter, created in the laboratory by means of the ultra-relativistic collision of two heavy nuclei. If two nuclei of high energy collide, they will create a zone of hot and dense matter, eventually having an energy density high enough to melt the individual nucleons into a soup of freely moving quarks and gluons, the above described QGP. The QGP will rapidly expand, and quarks will hadronize, mainly into charged and neutral mesons. The (very difficult) experimental task is to search amongst and amidst the abundantly created mesons for signatures of the early QGP phase

Relativistic finite-temperature Thomas-Fermi model

Science.gov (United States)

Faussurier, Gérald

2017-11-01

We investigate the relativistic finite-temperature Thomas-Fermi model, which has been proposed recently in an astrophysical context. Assuming a constant distribution of protons inside the nucleus of finite size avoids severe divergence of the electron density with respect to a point-like nucleus. A formula for the nuclear radius is chosen to treat any element. The relativistic finite-temperature Thomas-Fermi model matches the two asymptotic regimes, i.e., the non-relativistic and the ultra-relativistic finite-temperature Thomas-Fermi models. The equation of state is considered in detail. For each version of the finite-temperature Thomas-Fermi model, the pressure, the kinetic energy, and the entropy are calculated. The internal energy and free energy are also considered. The thermodynamic consistency of the three models is considered by working from the free energy. The virial question is also studied in the three cases as well as the relationship with the density functional theory. The relativistic finite-temperature Thomas-Fermi model is far more involved than the non-relativistic and ultra-relativistic finite-temperature Thomas-Fermi models that are very close to each other from a mathematical point of view.

Probing the Physics of Core-Collapse Supernovae and Ultra-Relativistic Outflows using Pulsar Wind Nebulae

Science.gov (United States)

Gelfand, Joseph

Core-collapse supernovae, the powerful explosions triggered by the gravitational collapse of massive stars, play an important role in evolution of star-forming galaxies like our Milky Way. Not only do these explosions eject the outer envelope of the progenitor star with extremely high velocities, creating a supernova remnant (SNR), the rotational energy of the resultant neutron star powers an ultra-relativistic outflow called a pulsar wind which creates a pulsar wind nebula (PWN) as it expands into its surroundings. Despite almost a century of study, many fundamental questions remain, including: How is a neutron star formed during a core-collapse supernova? How are particles created in the neutron star magnetosphere? How are particles accelerated to the PeV energies inside PWNe? Answering these questions requires measuring the properties of the progenitor star and pulsar wind for a diverse collection of neutron stars. Currently, this is best done by studying those PWNe inside a SNR, since their evolution is very sensitive to the initial spin period of the neutron star, the mass and initial kinetic energy of the supernova ejecta, and the magnetization and particle spectrum of the pulsar wind - quantities critical for answering the above questions. To this end, we propose to measure these properties for 17 neutron stars whose spin-down inferred dipole surface magnetic field strengths and characteristic ages differ by 1.5 orders of magnitude by fitting the broadband spectral energy distribution (SED) and dynamical properties of their associated PWNe with a model for the dynamical and spectral evolution of a PWN inside SNR. To do so, we will first re-analyze all archival X-ray (e.g., XMM, Chandra, INTEGRAL, NuSTAR) and gamma-ray (e.g., Fermi-LAT Pass 8) data on each PWN to ensure consistent measurements of the volume-integrated properties (e.g., X-ray photon index and unabsorbed flux, GeV spectrum) needed for this analysis. Additionally, we will use a Markoff Chain

138th International School of Physics "Enrico Fermi" : Unfolding the Matter of Nuclei

CERN Document Server

Ricci, R A

1998-01-01

The nucleus and its constituents are a challenging problem. The lectures collected in this book present a broad and comprehensive review of the current knowledge about nuclei.They cover topics such as searching for signatures of the quarks in nuclei with electromagnetic probes and, at much higher energies, for signatures of the quark-gluon plasma in ultrarelativistic nuclear collisions. The attempts to obtain new nuclei in the laboratory are also discussed, as well as the central role played by nuclear physics in the development of weak interactions. Progress in all these areas rests on a deeper theoretical handling of the nuclear and nucleon’s structure. The latter can also be addressed by relying on numerical solutions of QCD on a discrete space-time lattice. The advancement of computational capabilities has spurred a growing interest in this approach. Finally, the book deals with different paths toward solving non-perturbative QCD.

Workshop for Young Scientists on the Physics of Ultrarelativistic Nucleus-Nucleus Collisions

CERN Document Server

Bass, S; De Falco, A; Kuhn, C; Nardi, M; Peitzmann, T; Ullrich, T; Velkovska, J; Wiedemann, Urs Achim; HQ'06; Hot Quarks 2006

2007-01-01

One of the main challenges in nuclear and particle physics in the last 20 years has been to understand how the proton's spin is built up from its quark and gluon constituents. Quark models generally predict that about 60% of the proton's spin should be carried by the spin of the quarks inside, whereas high energy scattering experiments have shown that the quark spin contribution is small - only about 30%. This result has been the underlying motivation for about 1000 theoretical papers and a global program of dedicated spin experiments at BNL, CERN, DESY and Jefferson Laboratory to map the indi

Gauge field theories an introduction with applications

CERN Document Server

Guidry, Mike

1991-01-01

Acquaints readers with the main concepts and literature of elementary particle physics and quantum field theory. In particular, the book is concerned with the elaboration of gauge field theories in nuclear physics; the possibility of creating fundamental new states of matter such as an extended quark-gluon plasma in ultra-relativistic heavy ion collisions; and the relation of gauge theories to the creation and evolution of the universe. Divided into three parts, it opens with an introduction to the general principles of relativistic quantum field theory followed by the essential ingredients of gauge fields for weak and electromagnetic interactions, quantum chromodynamics and strong interactions. The third part is concerned with the interface between modern elementary particle physics and "applied disciplines" such as nuclear physics, astrophysics and cosmology. Includes references and numerous exercises

Reconstruction and study of the multi-strange baryons in ultra-relativistic heavy ion collisions at a center-of-mass energy of 200 GeV, with the Star experiment at RHIC

International Nuclear Information System (INIS)

Faivre, J.

2004-10-01

The study of strangeness production is essential for the understanding of processes occurring in ultra-relativistic heavy ion collisions. Strangeness production is directly linked to the phase of deconfined partons that followed these collisions: the quark and gluon plasma. STAR, one of the 4 experiments at RHIC collider, is a perfect tool for studying the multi-strange Ξ and Ω particles. We have devised a Ξ and Ω reconstruction program using signals from the STAR time projection chamber. We have worked out a multi-variable selection method for extracting the signals from the combinative background: the linear discriminant analysis. We have applied it to Au-Au collisions at 200 GeV (in the center of mass frame) to improve the accuracy of previous results. The Ω and anti-Ω production rates have been obtained for 3 ranges of centrality as well as their radial flow and their kinetic uncoupling temperatures. The gain on the relative uncertainty is between 15 and 30% according to the variable. The average speed of the radial flow is 0.50 ± 0.02 and the kinetic uncoupling temperature is 132 ± 20 MeV which indicates that multi-strange baryons uncouple in hadronic medium earlier that lighter particles like pions, kaons and protons. However, uncertainty intervals remain too broad to draw strong conclusions. (A.C.)

A new approach of chaos and complex network method to study fluctuation and phase transition in nuclear collision at high energy

Energy Technology Data Exchange (ETDEWEB)

Bhaduri, Susmita; Bhaduri, Anirban; Ghosh, Dipak [Deepa Ghosh Research Foundation, Kolkata (India)

2017-06-15

In the endeavour to study fluctuation and a signature of phase transition in ultrarelativistic nuclear collision during the process of particle production, an approach based on chaos and complex network is proposed. In this work we have attempted an exhaustive study of pion fluctuation in η space, φ space, their cross-correlation and finally two-dimensional fluctuation in terms of scaling of void probability distribution. The analysis is done on the η values and their corresponding φ values extracted from the {sup 32}S-Ag/Br interaction at an incident energy of 200 GeV per nucleon. The methods used are Multifractal Detrended Cross-Correlation Analysis (MF-DXA) and a chaos-based rigorous complex network method -Visibility Graph. The analysis reveals that the highest degree of cross-correlation between pseudorapidity and azimuthal angles exists in the most central region of the interaction. The analysis further shows that two-dimensional void distribution corresponding to the η-φ space reveals a strong scaling behaviour. Both cross-correlation coefficients of MF-DXA and PSVG (Power of the Scale-freeness in Visibility Graph, which is implicitly connected with the Hurst exponent) can be effectively used for the quantitative assessment of pion fluctuation in a very precise manner and have the capability to assess the tendency of approaching criticality for phase transitions. (orig.)

Two pion correlation from SPACER

International Nuclear Information System (INIS)

Csoergoe, T.; Zimanyi, J.; Pratt, S.

1989-12-01

The correlation function for neutral and negative pions produced in ultrarelativistic heavy ion collisions was calculated without free parameters based on a space-time version of the LUND model, called SPACER: Simulation of Phase space distribution of Atomic nuclear Collisions in Energetic Reactions. This method includes the effect of Bose correlations for the emitted pion pair. Effects arising from correlations between space-time and momentum space distributions are investigated. The results are compared to the data of two different experiments. The role and interpretation of the chaocity parameter are discussed. (D.G.) 14 refs.; 4 figs

TWO-PHOTON PHYSICS IN NUCLEUS-NUCLEUS COLLISIONS AT RHIC

International Nuclear Information System (INIS)

Nystrand, J.; Klein, S.

1998-01-01

Ultra-relativistic heavy-ions carry strong electromagnetic and nuclear fields. Interactions between these fields in peripheral nucleus-nucleus collisions can probe many interesting physics topics. This presentation will focus on coherent two-photon and photonuclear processes at RHIC. The rates for these interactions will be high. The coherent coupling of all the protons in the nucleus enhances the equivalent photon flux by a factor Z 2 up to an energy of ∼ 3 GeV. The plans for studying coherent interactions with the STAR experiment will be discussed. Experimental techniques for separating signal from background will be presented

Two-photon physics in nucleus-nucleus collisions at RHIC

International Nuclear Information System (INIS)

Nystrand, J.; Klein, S.

1998-01-01

Ultra-relativistic heavy-ions carry strong electromagnetic and nuclear fields. Interactions between these fields in peripheral nucleus-nucleus collisions can probe many interesting physics topics. This presentation will focus on coherent two-photon and photonuclear processes at RHIC. The rates for these interactions will be high. The coherent coupling of all the protons in the nucleus enhances the equivalent photon flux by a factor Z 2 up to an energy of ∼ 3 GeV. The plans for studying coherent interactions with the STAR experiment will be discussed. Experimental techniques for separating signal from background will be presented

Nuclear law - Nuclear safety

International Nuclear Information System (INIS)

Pontier, Jean-Marie; Roux, Emmanuel; Leger, Marc; Deguergue, Maryse; Vallar, Christian; Pissaloux, Jean-Luc; Bernie-Boissard, Catherine; Thireau, Veronique; Takahashi, Nobuyuki; Spencer, Mary; Zhang, Li; Park, Kyun Sung; Artus, J.C.

2012-01-01

This book contains the contributions presented during a one-day seminar. The authors propose a framework for a legal approach to nuclear safety, a discussion of the 2009/71/EURATOM directive which establishes a European framework for nuclear safety in nuclear installations, a comment on nuclear safety and environmental governance, a discussion of the relationship between citizenship and nuclear, some thoughts about the Nuclear Safety Authority, an overview of the situation regarding the safety in nuclear waste burying, a comment on the Nome law with respect to electricity price and nuclear safety, a comment on the legal consequences of the Fukushima accident on nuclear safety in the Japanese law, a presentation of the USA nuclear regulation, an overview of nuclear safety in China, and a discussion of nuclear safety in the medical sector

Physics Division progress report for period ending September 30, 1985

Energy Technology Data Exchange (ETDEWEB)

Livingston, A.B. (ed.)

1986-04-01

This report covers the research and development activities of the Physics Division for the 1985 fiscal year. The research activities were centered on experimental nuclear physics, experimental atomic physics, and theoretical nuclear and atomic physics. The experimental nuclear physics program is dominated by heavy ion research. A major part of this effort is the responsibility for operating the Holifield Heavy Ion Research Facility as a national user facility. A major new activity described is the preparation for participation in an ultrarelativistic heavy ion experiment to be performed at CERN in 1986. The experimental atomic physics program has two components: the accelerator-based studies of basic collisional phenomena and the studies in support of the controlled fusion program. Also associated with the fusion-related studies are a plasma diagnostics program and the operation of an atomic physics data center. Theory efforts associated with the UNISOR program are described, as well as smaller programs in applications and high-energy physics. (LEW)

Etude de la fragmentation des partons par la mesure de corrélations photon-hadron auprès de l'expérience ALICE au LHC

CERN Document Server

ARBOR, Nicolas

The strong interaction theory, Quantum Chromodynamic (QCD), predicts a new phase of nuclear matter at very high temperature and/or very high density. This state, which should have been the state of the Univers some microseconds after the Big Bang, is composed of deconfined quarks and gluons known as the quark-gluon plasma (QGP). The measurement of its composition and properties is a challenge for the nuclear physics of the 21st century and should lead to a better understanding of the fundamental symetries and mechanisms related to the quarks confinement inside hadrons and the strong interaction generally. The Large Hadron Collider (LHC) accelerator at CERN (European Organization for Nuclear Research) allows to reach the thermodynamic conditions required to create the quark-gluon plasma using ultra-relativistic heavy ion collisions (Pb). The ALICE experiment (A Large Ion Collider Experiment) allows to access several probes to characterize the QGP through particles reconstruction and. Among these probes, hi...

Physics Division progress report for period ending September 30, 1985

International Nuclear Information System (INIS)

Livingston, A.B.

1986-04-01

This report covers the research and development activities of the Physics Division for the 1985 fiscal year. The research activities were centered on experimental nuclear physics, experimental atomic physics, and theoretical nuclear and atomic physics. The experimental nuclear physics program is dominated by heavy ion research. A major part of this effort is the responsibility for operating the Holifield Heavy Ion Research Facility as a national user facility. A major new activity described is the preparation for participation in an ultrarelativistic heavy ion experiment to be performed at CERN in 1986. The experimental atomic physics program has two components: the accelerator-based studies of basic collisional phenomena and the studies in support of the controlled fusion program. Also associated with the fusion-related studies are a plasma diagnostics program and the operation of an atomic physics data center. Theory efforts associated with the UNISOR program are described, as well as smaller programs in applications and high-energy physics

High-$p_\\mathrm{T}$ probes of $p$+Pb collisions with ATLAS

CERN Document Server

Perepelitsa, Dennis; The ATLAS collaboration

2015-01-01

Measurements of high $p_\\mathrm{T}$ processes in ultrarelativistic proton--nucleus collisions are sensitive to changes in the partonic densities arising from the presence of the nuclear environment. Additionally, such measurements benchmark the so called ``cold nuclear matter'' effects, providing the context within which to understand the strong suppression of high $p_\\mathrm{T}$ processes observed in nucleus--nucleus collisions. Furthermore, measurements of the centrality dependence of jet production at forward (proton-going) rapidities may even shed light on the behavior of the proton wavefunction at large Bjorken-$x$. The latest ATLAS results for inclusive jets and charged particles in 28/nb of $5.02$~TeV proton--lead collisions at the LHC are presented. The centrality in these collisions is characterized through the sum of the transverse energy in the lead-going forward calorimeter. The nuclear modification factors $R_{p\\mathrm{Pb}}$ and $R_\\mathrm{CP}$ are presented for jets and charged particles as a fu...

Longitudinal decorrelation measures of flow magnitude and event-plane angles in ultrarelativistic nuclear collisions

Science.gov (United States)

BoŻek, Piotr; Broniowski, Wojciech

2018-03-01

We discuss the forward-backward correlations of harmonic flow in Pb +Pb collisions at the CERN Large Hadron Collider, applying standard multibin measures as well as new measures proposed here. We illustrate the methods with hydrodynamic model simulations based on event-by-event initial conditions from the wounded quark model with asymmetric rapidity emission profiles. Within the model, we examine independently the event-plane angle and the flow magnitude decorrelations. We find a specific hierarchy between various flow decorrelation measures and confirm certain factorization relations. We find qualitative agreement of the model and the data from the ATLAS and CMS Collaborations.

Finite size and dynamical effects in pair production by an external field

International Nuclear Information System (INIS)

Martin, C.; Vautherin, D.

1988-12-01

We evaluate the rate of pair production in a uniform electric field confined into a bounded region in space. Using the Balian-Bloch expansion of Green's functions we obtain explicit expressions for finite size corrections to Schwinger's formula. The case of a time-dependent boundary, relevant to describe energy deposition by quark-antiquark pair production in ultrarelativistic collisions, is also investigated. We find that finite size effects are important in nuclear collisions. They decrease when the strength of the chromo-electric field between the nuclei is large. As a result, the rate of energy deposition increases sharply with the mass number A of the colliding nuclei

Study of Z boson production in the muon decay channel in pPb collisions at sqrt(sNN) = 5.02 TeV

CERN Document Server

CMS Collaboration

2015-01-01

The electroweak boson production is an important benchmark measurement in ultrarelativistic heavy-ion collisions which can provide constraints on the nuclear modification of parton distribution functions. In this paper the results from the proton-lead collision data taken in early 2013 are presented. The Z boson production is studied in the electron and muon decay channels. The cross section is measured in bins of the Z~boson rapidity and transverse momentum and compared to theoretical predictions. The Z~boson production is observed to be proportional to the number of elementary nucleon-nucleon collisions within the uncertainties. The forward-backward ratio of the measured cross section is presented.

High-pT hadron spectra at RHIC: an overview

International Nuclear Information System (INIS)

Klay, Jennifer L

2005-01-01

Recent results on high transverse momentum (p T ) hadron production in p+p, d+Au and Au+Au collisions at the relativistic heavy-ion collider (RHIC) are reviewed. Comparison of the nuclear modification factors, R dAu (p T ) and R AA (p T ), demonstrates that the large suppression in central Au+Au collisions is due to strong final-state effects. Theoretical models which incorporate jet quenching via gluon bremsstrahlung in the dense partonic medium that is expected in central Au+Au collisions at ultra-relativistic energies are shown to reproduce the shape and magnitude of the observed suppression over the range of collision energies so far studied at RHIC

Oregon State University nuclear chemistry progress report, August 1, 1988--August 1, 1989

International Nuclear Information System (INIS)

Loveland, W.D.

1989-08-01

The work described herein is part of a project involving the study of intermediate energy, and relativistic heavy ion reactions. The intermediate energy research focused on the characterization of the heavy residues, the large target fragments with A frag >2/3 A target . For the reaction of 85 MeV/nucleon 12 C with 197 Au, we had measured the heavy residue yields and angular distributions previously. We report herein the measurement of their energy spectra. The average residue energies are quite low, ranging from 15 keV/nucleon to 314 keV/nucleon. These low energies imply errors in some previous measurements of heavy residues in that many residues have energies below counter thresholds, etc. The essential physics of heavy residue production is shown to be correctly described by a VUU calculation. For the reaction of 35 and 43 MeV/nucleon Kr with Au, we found the linear momenta of the near-target heavy residues to be in agreement with models of peripheral collisions. For the heavy residues with large ΔA values, the residue linear momenta approach a limiting value which is far below that expected from the ''universal'' systematics of linear momentum transfer in reactions induced by smaller projectiles. Reasons for this limiting behavior are suggested. In the area of relativistic nuclear collisions, complete target fragment mass distributions were measured for the ultrarelativistic reactions of 13.6 GeV/nucleon 16 O and 28 Si with 197 Au. An unexpected finding in this study was the relatively large cross section for the two neutron removal process via electromagnetic dissociation. Similar measurements for the reaction of 1.1 GeV/nucleon 197 Au with 197 Au furnished the first complete fragment mass distribution for that reaction

Nuclear energy and the nuclear industry

International Nuclear Information System (INIS)

1979-01-01

These notes have been prepared by the Department of Energy to provide information and to answer questions often raised about nuclear energy and the nuclear industry and in the hope that they will contribute to the public debate about the future of nuclear energy in the UK. The subject is dealt with under the headings; contribution of nuclear power, energy forecasts, nuclear fuels and reactor types, cost, thermal reactor strategy, planning margin, safety, nuclear licensing, unlike an atomic bomb, radiation, waste disposal, transport of nuclear materials, emergency arrangements at nuclear sites, siting of nuclear stations, security of nuclear installations, world nuclear programmes, international regulation and non-proliferation, IAEA safeguards arrangements in the UK, INFCE, and uranium supplies. (U.K.)

Non-Gestational Choriocarcinoma with Widespread Metastases Presenting with Type 1 Respiratory Failure in a 39-Year-Old Female: Case Report and Review of the Literature

Directory of Open Access Journals (Sweden)

Louisa Stockton

2018-03-01

Full Text Available Introduction: Non-gestational choriocarcinoma (NGCC is an extremely rare cancer. We report a case presenting in extremis. Case Report: A 39-year-old woman presented with type 1 respiratory failure with a 1-month history of breathlessness. Computed tomography (CT revealed widespread metastatic disease involving the lungs, liver, pancreas, and breast. Serum β-human chorionic gonadotropin was markedly raised. Over 72 h, she deteriorated and was started on high-flow nasal cannula to facilitate discussions and for comfort. Histology from a breast biopsy suggested a choriocarcinoma, and she was commenced on etoposide and cisplatin. Unfortunately she continued to deteriorate and died on day 11 of admission. Molecular genotyping received post-mortem confirmed non-gestational choriocarcinomatous differentiation within a high-grade tumour. Discussion: NGCC carries a worse prognosis compared with gestational choriocarcinoma and is historically less chemosensitive. However, differentiation between these two diagnoses is challenging due to a lack of immuno-histochemical differences. The NGCC in this case was likely to have originated in the lung due to a 12-cm mass in the lingula, and extensive emphysema on CT. Primary pulmonary choriocarcinoma has a rapidly fatal course in the majority of patients. Conclusion: This is the only case to our knowledge of NGCC presenting in extremis, where an accurate diagnosis was not achieved pre-mortem. This also demonstrates the merit of non-invasive ventilation within palliation to facilitate communication and comfort.

Invisible nuclear; converting nuclear

International Nuclear Information System (INIS)

Park, Jongmoon

1993-03-01

This book consists of 14 chapters which are CNN era and big science, from East and West to North and South, illusory nuclear strategy, UN and nuclear arms reduction, management of armaments, advent of petroleum period, the track of nuclear power generation, view of energy, internationalization of environment, the war over water in the Middle East, influence of radiation and an isotope technology transfer and transfer armament into civilian industry, the end of nuclear period and the nuclear Nonproliferation, national scientific and technological power and political organ and executive organ.

A Delicate Balance of Different Dependencies

DEFF Research Database (Denmark)

Brincker, Benedikte

, the region holds promises of an abundance of natural resources and the prospect of new international trade routes. This draws attention to one particular country: Greenland. Greenland is part of the Kingdom of Denmark – but it has for many years witnessed moves towards national independence. These calls...... of balancing different dependencies. In this perspective, Greenland is the case in extremis. The prospect of Greenland seceding from the Kingdom of Denmark relies upon it becoming embedded in the “international community of sovereign nation states” thus balancing different dependencies ‐ while also...

Institute for Nuclear Research and Nuclear Energy and Nuclear Science

International Nuclear Information System (INIS)

Stamenov, J.

2004-01-01

The Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences is the leading Bulgarian Institute for scientific investigations and applications of nuclear science. The main Institute's activities in the field of elementary particles and nuclear physics, high energy physics and nuclear energy, radiochemistry, radioecology, radioactive wastes treatment, monitoring of the environment, nuclear instruments development ect. are briefly described. Several examples for: environmental radiation monitoring; monitoring of the radioactivity and heavy metals in aerosols, 99m Tc clinical use, Boron Neutron Capture Therapy application of IRT-2000 Research Reactor, neutron fluence for reactor vessel embrittlement, NPP safety analysis, nuclear fuel modelling are also presented

Nuclear power and nuclear weapons

International Nuclear Information System (INIS)

Vaughen, V.C.A.

1983-01-01

The proliferation of nuclear weapons and the expanded use of nuclear energy for the production of electricity and other peaceful uses are compared. The difference in technologies associated with nuclear weapons and nuclear power plants are described

Nuclear safety. Seguranca nuclear

Energy Technology Data Exchange (ETDEWEB)

Aveline, A [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Inst. de Fisica

1981-01-01

What is nuclear safety Is there any technical way to reduce risks Is it possible to put them at reasonable levels Are there competitiveness and economic reliability to employ the nuclear energy by means of safety technics Looking for answers to these questions the author describes the sources of potential risks to nuclear reactors and tries to apply the answers to the Brazilian Nuclear Programme. (author).

Non-equilibrium many body dynamics

International Nuclear Information System (INIS)

Creutz, M.; Gyulassy, M.

1997-01-01

This Riken BNL Research Center Symposium on Non-Equilibrium Many Body Physics was held on September 23-25, 1997 as part of the official opening ceremony of the Center at Brookhaven National Lab. A major objective of theoretical work at the center is to elaborate on the full spectrum of strong interaction physics based on QCD, including the physics of confinement and chiral symmetry breaking, the parton structure of hadrons and nuclei, and the phenomenology of ultra-relativistic nuclear collisions related to the up-coming experiments at RHIC. The opportunities and challenges of nuclear and particle physics in this area naturally involve aspects of the many body problem common to many other fields. The aim of this symposium was to find common theoretical threads in the area of non-equilibrium physics and modern transport theories. The program consisted of invited talks on a variety topics from the fields of atomic, condensed matter, plasma, astrophysics, cosmology, and chemistry, in addition to nuclear and particle physics. Separate abstracts have been indexed into the database for contributions to this workshop

Non-equilibrium many body dynamics

Energy Technology Data Exchange (ETDEWEB)

Creutz, M.; Gyulassy, M.

1997-09-22

This Riken BNL Research Center Symposium on Non-Equilibrium Many Body Physics was held on September 23-25, 1997 as part of the official opening ceremony of the Center at Brookhaven National Lab. A major objective of theoretical work at the center is to elaborate on the full spectrum of strong interaction physics based on QCD, including the physics of confinement and chiral symmetry breaking, the parton structure of hadrons and nuclei, and the phenomenology of ultra-relativistic nuclear collisions related to the up-coming experiments at RHIC. The opportunities and challenges of nuclear and particle physics in this area naturally involve aspects of the many body problem common to many other fields. The aim of this symposium was to find common theoretical threads in the area of non-equilibrium physics and modern transport theories. The program consisted of invited talks on a variety topics from the fields of atomic, condensed matter, plasma, astrophysics, cosmology, and chemistry, in addition to nuclear and particle physics. Separate abstracts have been indexed into the database for contributions to this workshop.

Nuclear safety culture and nuclear safety supervision

International Nuclear Information System (INIS)

Chai Jianshe

2013-01-01

In this paper, the author reviews systematically and summarizes up the development process and stage characteristics of nuclear safety culture, analysis the connotation and characteristics of nuclear safety culture, sums up the achievements of our country's nuclear safety supervision, dissects the challenges and problems of nuclear safety supervision. This thesis focused on the relationship between nuclear safety culture and nuclear safety supervision, they are essential differences, but there is a close relationship. Nuclear safety supervision needs to introduce some concepts of nuclear safety culture, lays emphasis on humanistic care and improves its level and efficiency. Nuclear safety supervision authorities must strengthen nuclear safety culture training, conduct the development of nuclear safety culture, make sure that nuclear safety culture can play significant roles. (author)

Nuclear energy and nuclear weapons

International Nuclear Information System (INIS)

Robertson, J.A.L.

1983-06-01

We all want to prevent the use of nuclear weapons. The issue before us is how best to achieve this objective; more specifically, whether the peaceful applications of nuclear energy help or hinder, and to what extent. Many of us in the nuclear industry are working on these applications from a conviction that without peaceful nuclear energy the risk of nuclear war would be appreciably greater. Others, however, hold the opposite view. In discussing the subject, a necessary step in allaying fears is understanding some facts, and indeed facing up to some unpalatable facts. When the facts are assessed, and a balance struck, the conclusion is that peaceful nuclear energy is much more part of the solution to preventing nuclear war than it is part of the problem

Eleven lectures on the physics of the quark-gluon plasma

International Nuclear Information System (INIS)

McLerran, L.

1984-10-01

These lectures are intended to be an introduction to the physics of the quark-gluon plasma, and were presented at a workshop on The Physics of the Quark-Gluon Plasma held at Hua-Zhong Normal University in Wuhan, People's Republic of China in September, 1983. The lectures cover perturbation theory of the plasma at high temperature as well as the non-perturbative methods and results of lattice gauge theory computations. Physical models of the confinement-deconfinement phase transition and the modes of chiral symmetry breaking are presented. The possibility that a quark-gluon plasma might be produced in ultra-relativistic nuclear collisions is analyzed. Separate entries were prepared for the data base for the eleven lectures

Experimental status of the search for the quark-gluon plasma in ultra-relativistic heavy ion interactions

International Nuclear Information System (INIS)

Salmeron, R.A.

1992-01-01

The deconfinement of quarks, antiquarks and gluons, and the phase transition from a hadron phase to a quark-gluon plasma phase are presented after recalling some elementary notions about normal nuclear matter. Eight proposed signatures of the quark-gluon plasma are described and a summary is given of the experiments concerning three of them: Bose-Einstein interference, the suppression of the J/ψ production and strange particles production. (author)

Evidence of Wigner rotation phenomena in the beam splitting experiment at the LCLS

International Nuclear Information System (INIS)

Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

2016-07-01

A result from particle tracking states that, after a microbunched electron beam is kicked, its trajectory changes while the orientation of the microbunching wavefront remains as before. Experiments at the LCLS showed that radiation in the kicked direction is produced practically without suppression. This could be explained if the orientation of the microbunching wavefront is readjusted along the kicked direction. In previous papers we showed that when the evolution of the electron beam modulation is treated according to relativistic kinematics, the orientation of the microbunching wavefront in the ultrarelativistic asymptotic is always perpendicular to the electron beam velocity. There we refrained from using advanced theoretical concepts to explain or analyze the wavefront rotation. For example, we only hinted to the relation of this phenomenon with the concept of Wigner rotation. This more abstract view of wavefront rotation underlines its elementary nature. The Wigner rotation is known as a fundamental effect in elementary particle physics. The composition of non collinear boosts does not result in a simple boost but, rather, in a Lorentz transformation involving a boost and a rotation, the Wigner rotation. Here we show that during the LCLS experiments, a Wigner rotation was actually directly recorded for the first time with a ultrarelativistic, macroscopic object: an ultrarelativistic electron bunch in an XFEL modulated at nm-scale of the size of about 10 microns. Here we point out the role of Wigner rotation in the analysis and interpretation of experiments with ultrarelativistic, microbunched electron beams in FELs. After the beam splitting experiment at the LCLS it became clear that, in the ultrarelativistic asymptotic, the projection of the microbunching wave vector onto the beam velocity is a Lorentz invariant, similar to the helicity in particle physics.

Evidence of Wigner rotation phenomena in the beam splitting experiment at the LCLS

Energy Technology Data Exchange (ETDEWEB)

Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2016-07-15

A result from particle tracking states that, after a microbunched electron beam is kicked, its trajectory changes while the orientation of the microbunching wavefront remains as before. Experiments at the LCLS showed that radiation in the kicked direction is produced practically without suppression. This could be explained if the orientation of the microbunching wavefront is readjusted along the kicked direction. In previous papers we showed that when the evolution of the electron beam modulation is treated according to relativistic kinematics, the orientation of the microbunching wavefront in the ultrarelativistic asymptotic is always perpendicular to the electron beam velocity. There we refrained from using advanced theoretical concepts to explain or analyze the wavefront rotation. For example, we only hinted to the relation of this phenomenon with the concept of Wigner rotation. This more abstract view of wavefront rotation underlines its elementary nature. The Wigner rotation is known as a fundamental effect in elementary particle physics. The composition of non collinear boosts does not result in a simple boost but, rather, in a Lorentz transformation involving a boost and a rotation, the Wigner rotation. Here we show that during the LCLS experiments, a Wigner rotation was actually directly recorded for the first time with a ultrarelativistic, macroscopic object: an ultrarelativistic electron bunch in an XFEL modulated at nm-scale of the size of about 10 microns. Here we point out the role of Wigner rotation in the analysis and interpretation of experiments with ultrarelativistic, microbunched electron beams in FELs. After the beam splitting experiment at the LCLS it became clear that, in the ultrarelativistic asymptotic, the projection of the microbunching wave vector onto the beam velocity is a Lorentz invariant, similar to the helicity in particle physics.

Strange hadrons and antiprotons as probes of hot and dense nuclear matter in relativistic heavy-ion collisions; Seltsame Hadronen und Antiprotonen als Proben heisser und dichter Kernmaterie in relativistischen Schwerionenkollisionen

Energy Technology Data Exchange (ETDEWEB)

Schade, Henry

2010-09-15

Strange particles play an important role as probes of relativistic heavy-ion collisions where hot and dense matter is studied. The focus of this thesis is on the production of strange particles within a transport model of Boltzmann-Uehling-Uhlenbeck (BUU) type. Current data of the HADES Collaboration concerning K{sup {+-}} and {phi} spectra provide the appropriate experimental framework. Moreover, the double-strange hyperon {xi}{sup -} is analyzed below the free NN production threshold. Hadron multiplicities, transversemomentum and rapidity spectra are compared with recent experimental data. Further important issues are in-medium mass shifts, the nuclear equation of state as well as the mean field of nucleons. Besides the study of AA collisions a comparison with recent ANKE data regarding the {phi} yield in pA collisions is done. Transparency ratios are determined and primarily investigated for absorption of {phi} mesons by means of the BUU transport code. Thereby, secondary {phi} production channels, isospin asymmetry and detector acceptance are important issues. A systematic analysis is presented for different system sizes. The momentum integrated Boltzmann equations describe dense nuclear matter on a hadronic level appearing in the Big Bang as well as in little bangs, in the context of kinetic off-equilibrium dynamics. This theory is applied to antiprotons and numerically calculated under consideration of various expansion models. Here, the evolution of proton- and antiproton densities till freeze-out is analyzed for ultra-relativistic heavy-ion collisions within a hadrochemic resonance gas model acting as a possible ansatz for solving the ''antiproton puzzle''. Furthermore, baryonic matter and antimatter is investigated in the early universe and the adiabatic path of cosmic matter is sketched in the QCD phase diagram. (orig.)

Nuclear reaction data and nuclear reactors

Energy Technology Data Exchange (ETDEWEB)

Paver, N [University of Trieste (Italy); Herman, M [International Atomic Energy Agency, Vienna (Austria); Gandini, A [ENEA, Rome (Italy)

2001-12-15

These two volumes contain the lecture notes of the workshop 'Nuclear Reaction Data and Nuclear Reactors: Physics, Design and Safety', which was held at the Abdus Salam ICTP in the Spring of 2000. The workshop consisted of five weeks of lecture courses followed by practical computer exercises on nuclear data treatment and design of nuclear power systems. The spectrum of topics is wide enough to timely cover the state-of-the-art and the perspectives of this broad field. The first two weeks were devoted to nuclear reaction models and nuclear data evaluation. Nuclear data processing for applications to reactor calculations was the subject of the third week. On the last two weeks reactor physics and on-going projects in nuclear power generation, waste disposal and safety were presented.

Nuclear astrophysics: An application of nuclear physics

International Nuclear Information System (INIS)

Fueloep, Z.

2005-01-01

Nuclear astrophysics, a fruitful combination of nuclear physics and astrophysics can be viewed as a special application of nuclear physics where the study of nuclei and their reactions are motivated by astrophysical problems. Nuclear astrophysics is also a good example for the state of the art interdisciplinary research. The origin of elements studied by geologists is explored by astrophysicists using nuclear reaction rates provided by the nuclear physics community. Due to the high interest in the field two recent Nuclear Physics Divisional Conferences of the European Physical Society were devoted to nuclear astrophysics and a new conference series entitled 'Nuclear Physics in Astrophysics' has been established. Selected problems of nuclear astrophysics will be presented emphasizing the interplay between nuclear physics and astrophysics. As an example the role of 14 N(p,r) 15 O reaction rate in the determination of the age of globular clusters will be discussed in details

Interrelationship between nuclear safety, safeguards and nuclear security

International Nuclear Information System (INIS)

Irie, Kazutomo

2007-01-01

As preventive activities against danger within nuclear systems, three major areas exist; nuclear safety, safeguards and nuclear security. Considering the purpose of these activities, to prevent non-peaceful use is common in nuclear security in general and safeguards. At the same time, measures against sabotage, one of the subcategory in nuclear security, is similar to nuclear safety in aiming at preventing nuclear accidents. When taking into account the insider issues in nuclear security, the distinction between measures against sabotage and nuclear safety becomes ambiguous. Similarly, the distinction between measures against theft, another subcategory in nuclear security, and safeguards also becomes vague. These distinctions are influenced by psychological conditions of members in nuclear systems. Members who have the intention to make nuclear systems dangerous to human society shall be the 'enemy' to nuclear systems and thus be the target for nuclear security. (author)

Nuclear blackmail and nuclear balance

International Nuclear Information System (INIS)

Betts, R.K.

1987-01-01

This book raises pointed questions about nuclear saber rattling. More than a dozen cases since the bombing of Hiroshima and Magasaki in which some sort of nuclear threat was used as a sparring technique in tense confrontations are cited. Each incident is described and analyzed. Two theories offered to explain America's use of nuclear threats, the balance of interest theory and the balance of power theory, are contrasted throughout the book. This book helps to fill the gap in the understanding of nuclear weapons and their uses, while pointing out that nuclear bravado could lead to an unintended unleashing of these weapons

New horizons in fundamental physics

CERN Document Server

Schäfer, Mirko

2017-01-01

This volume presents the state-of-the-art in selected topics across modern nuclear physics, covering fields of central importance to research and illustrating their connection to many different areas of physics. It describes recent progress in the study of superheavy and exotic nuclei, which is pushing our knowledge to ever heavier elements and neutron-richer isotopes. Extending nuclear physics to systems that are many times denser than even the core of an atomic nucleus, one enters the realm of the physics of neutron stars and possibly quark stars, a topic that is intensively investigated with many ground-based and outer-space research missions as well as numerous theoretical works. By colliding two nuclei at very high ultra-relativistic energies one can create a fireball of extremely hot matter, reminiscent of the universe very shortly after the big bang, leading to a phase of melted hadrons and free quarks and gluons, the so-called quark-gluon plasma. These studies tie up with effects of crucial importance...

Measurement of jet fragmentation functions and of their moments in $pp$ collisions at $\\sqrt{s}=2.76$ TeV with ALICE at the LHC

CERN Document Server

AUTHOR|(CDS)2074876; Kabana, Sonja; Shabetai, Alexandre; Zhou, Daicui

A cross-over between ordinary nuclear matter and a state of de-confined quarks and gluons, the Quark Gluon Plasma (QGP), is predicted by lattice QCD calculations at low chemical potential and high temperature in the nuclear phase diagram. Experimentally, ultra-relativistic heavy ion collisions are used to produce and study the hot and dense QGP medium. Produced in a hard scattering at the early stage of the collision a highly energetic parton is first expected to lose energy in the medium before fragmenting into a hadronic spray of particles called jet. A detailed study of the modification of the jet structure and of its fragmentation pattern in vacuum and in medium should provide insights into the QGP properties. The jet fragmentation functions describe the momentum distribution of hadrons inside a reconstructed jet. In proton-proton ($pp$) collisions their measurement is important for understanding the mechanisms of parton fragmentation. Such measurements also provide a test of perturbative Quantum Chro...

Measurement of D$^{+}$ meson production in p-Pb collisions with the ALICE detector

CERN Document Server

Russo, Riccardo

2015-01-01

The main goal of the experimental programs on ultra-relativistic heavy ion collisions at the LHC is the production and characterization of the Quark Gluon Plasma (QGP), a phase of nuclear matter in which strongly interacting constituents (quarks and gluons) are deconfined. Heavy quarks are considered effective probes of the properties of the QGP as they are created on a short time scale, with respect to that of the QGP, and subsequently interact with it. Moreover, for a proper assessment of the characteristics of the matter produced in heavy-ion collisions, it is important to disentangle the final state effects due to the formation of a QGP from the initial state effects due to the fact that nuclei are present in the colliding system. Both initial and final state effects may lead to qualitatively similar phenomena in the observables of interest. The measurement of charmed meson production in proton-nucleus collisions allows to assess initial state effects present in nuclear collisions, under the assumption th...

Future of the ATLAS heavy ion program

CERN Document Server

ATLAS-Collaboration, The; The ATLAS collaboration

2012-01-01

The primary goal of the heavy ion program at the LHC is to study the properties of deconfined strongly interacting matter, often referred to as ``quark-gluon plasma'' (QGP), created in ultra-relativistic nuclear collisions. That matter is found to be strongly coupled with a viscosity to entropy ratio near a conjectured quantum lower bound. ATLAS foresees a rich program of studies using jets, Upsilons, measurements of global event properties and measurements in proton-nucleus collisions that will measure fundamental transport properties of the QGP, probe the nature of the interactions between constituents of the QGP, elucidate the origin of the strong coupling, and provide insight on the initial state of nuclear collisions. The heavy ion program through the third long shutdown should provide one inverse nb of 5.5~TeV Pb+Pb data. That data will provide more than an order of magnitude increase in statistics over currently available data for high-pT observables such as gamma-jet and Z-jet pairs. However, potentia...

Strangeness production in p-Pb and Pb-Pb collisions with ALICE at LHC

CERN Document Server

Colella, Domenico

2017-01-01

The main goal of the ALICE experiment is to study the properties of the hot and dense medium created in ultra-relativistic heavy-ion collisions. The measurement of the (multi-)strange particles is an important tool to understand particle production mechanisms and the dynamics of the quark-gluon plasma (QGP). We report on the production of K$^{0}_{S}$, $\\Lambda$($\\overline{\\Lambda}$), $\\Xi^{-}$($\\overline{\\Xi}^{+}$) and $\\Omega^{-}$($\\overline{\\Omega}^{+}$) in proton-lead (p-Pb) collisions at $\\sqrt{s_{\\rm NN}}$ = 5.02 TeV and lead-lead (Pb-Pb) collisions at $\\sqrt{s_{\\rm NN}}$ = 2.76 TeV measured by ALICE at the LHC. The comparison of the hyperon-to-pion ratios in the two colliding systems may provide insight into strangeness production mechanisms, while the comparison of the nuclear modification factors helps to determine the contribution of initial state effects and the suppression from strange quark energy loss in nuclear matter.

The ALICE time machine

Directory of Open Access Journals (Sweden)

Ferretti Alessandro

2013-09-01

Full Text Available According to the Big Bang theory, the Universe was once in an extremely hot and dense state which expanded rapidly. In such a state the normal nuclear matter could not exist: it is believed that a few microsecond after big-bang the matter underwent a phase transition, from a state called Quark-Gluon Plasma (QGP to a hadron gas. Some of the unexplained features of the Universe could be explained by the QGP properties. One of the aims of the CERN LHC is to recreate (on a smaller scale a QGP state, compressing and heating ordinary nuclear matter by means of ultrarelativistic heavy-ion collisions. The ALICE experiment at CERN is dedicated to the study of the medium produced in these collisions : in particular, the study of the heavy quarkonia suppression pattern can give a measure of the temperature reached in these collisions, helping us to understand how close we are getting to the conditions of the starting point of the Universe.

Advanced nuclear reactor and nuclear fusion power generation

International Nuclear Information System (INIS)

2000-04-01

This book comprised of two issues. The first one is a advanced nuclear reactor which describes nuclear fuel cycle and advanced nuclear reactor like liquid-metal reactor, advanced converter, HTR and extra advanced nuclear reactors. The second one is nuclear fusion for generation energy, which explains practical conditions for nuclear fusion, principle of multiple magnetic field, current situation of research on nuclear fusion, conception for nuclear fusion reactor and economics on nuclear fusion reactor.

Nuclear orientation and nuclear structure

International Nuclear Information System (INIS)

Krane, K.S.

1988-01-01

The present generation of on-line nuclear orientation facilities promises to revolutionize the gathering of nuclear structure information, especially for the hitherto poorly known and understood nuclei far from stability. Following a brief review of the technological developments that have facilitated these experiments, the nuclear spectroscopic information that can be obtained is summarized. Applications to understanding nuclear structure are reviewed, and challenges for future studies are discussed. (orig.)

Nuclear experts and nuclear weapons proliferation

International Nuclear Information System (INIS)

Mueller, H.

1979-01-01

In Germany the issue of nuclear weapons proliferation has attracted scant attention. Most potential nuclear weapon states are important trade partners of the FRG and, since further proliferation of nuclear weapons could worsen conflicts involving these, it should be in the FRG's interest to limit proliferation. The security of the FRG is also dependent on the common interest of the great powers to avoid nuclear war. The contradictory positions of Usa and the USSR on nuclear weapons policy regarding themselves and non-nuclear weapon states encourages less developed countries to see nuclear weaponry as useful. The NPT and IAEA safeguards have only limited inhibiting effect. The nuclear export policy of the FRG has been dominated by short term economic advantage, neglecting the negative long term effects of decreased political stability. The FRG should formulate a policy based on self-restraint, positive stimuli and extension of controls, using its economic strength to deter proliferation. (JIW)

World Nuclear Association position statement: Safe management of nuclear waste and used nuclear fuel

International Nuclear Information System (INIS)

Saint-Pierre, Sylvain

2006-01-01

This WNA Position Statement summarises the worldwide nuclear industry's record, progress and plans in safely managing nuclear waste and used nuclear fuel. The global industry's safe waste management practices cover the entire nuclear fuel-cycle, from the mining of uranium to the long-term disposal of end products from nuclear power reactors. The Statement's aim is to provide, in clear and accurate terms, the nuclear industry's 'story' on a crucially important subject often clouded by misinformation. Inevitably, each country and each company employs a management strategy appropriate to a specific national and technical context. This Position Statement reflects a confident industry consensus that a common dedication to sound practices throughout the nuclear industry worldwide is continuing to enhance an already robust global record of safe management of nuclear waste and used nuclear fuel. This text focuses solely on modern civil programmes of nuclear-electricity generation. It does not deal with the substantial quantities of waste from military or early civil nuclear programmes. These wastes fall into the category of 'legacy activities' and are generally accepted as a responsibility of national governments. The clean-up of wastes resulting from 'legacy activities' should not be confused with the limited volume of end products that are routinely produced and safely managed by today's nuclear energy industry. On the significant subject of 'Decommissioning of Nuclear Facilities', which is integral to modern civil nuclear power programmes, the WNA will offer a separate Position Statement covering the industry's safe management of nuclear waste in this context. The paper's conclusion is that the safe management of nuclear waste and used nuclear fuel is a widespread, well-demonstrated reality. This strong safety record reflects a high degree of nuclear industry expertise and of industry responsibility toward the well-being of current and future generations. Accumulating

Nuclear Law: A Key Against Nuclear Terrorism

International Nuclear Information System (INIS)

Cardozo, P.

2004-01-01

The role of the legal instruments in the war against nuclear terrorism. Control of radioactive sources. Elements of Nuclear Law: Definition: it is the body of special legislation that regulates the pacific uses of nuclear energy and the conduct of the persons engaged in activities related to fissionable materials and ionizing radiation . Objective: to provide a legal framework in order to protect individuals , property and the environment against the harmful effects of the use of nuclear energy and ionising radiation. Principles of nuclear energy legislation: safety principle, exclusively operator responsibility, authorization, independence of the regulatory body, inspections and enforcement, nuclear damage compensation, international cooperation. National regulatory infrastructure. Establishment of special law in Emergency Preparedness for nuclear or radiological disaster. IAEA Conventions. Transportation of nuclear material. IAEA regulations on radioactive material. Compensation for nuclear damage. Nuclear safety, security and terrorism. International and domestic instruments. Anti terrorism acts. International agreements on Safety Cooperation. (Author)

The role of nuclear law in nuclear safety after Fukushima; El rol del derecho nuclear en seguridad nuclear luego de Fukushima

Energy Technology Data Exchange (ETDEWEB)

Cardozo, Diva E. Puig, E-mail: d.puig@adinet.com.uy [International Nuclear Law Association (INLA), Montevideo (Uruguay)

2013-07-01

The paper contains the following topics: nuclear law, origin and evolution, role of the legal instruments on nuclear safety, nuclear safety the impact of major nuclear accidents: Chernobyl and Fukushima. The response of the nuclear law post Fukushima. Safety and security. International framework for nuclear safety: nuclear convention joint convention on safety on spent fuel management and on the safety of radioactive waste management. The Fukushima World Conference on Nuclear Safety. Convention on Prompt Notification and Assistance in case of a Nuclear Accident or Radiological Emergency. Plan of Action for Nuclear Safety. IAEA recommendations for the safety transport of radioactive material. International framework for nuclear security. Convention on the Physical Protection of Nuclear Materials. International Convention for the Suppression of Acts Against Nuclear Terrorism. Resolution No. 1540 of the Security Council of United Nations (2004). Measures to strengthen international safety. Code of conduct on the safety research reactor.

The Arabidopsis Nuclear Pore and Nuclear Envelope

OpenAIRE

Meier, Iris; Brkljacic, Jelena

2010-01-01

The nuclear envelope is a double membrane structure that separates the eukaryotic cytoplasm from the nucleoplasm. The nuclear pores embedded in the nuclear envelope are the sole gateways for macromolecular trafficking in and out of the nucleus. The nuclear pore complexes assembled at the nuclear pores are large protein conglomerates composed of multiple units of about 30 different nucleoporins. Proteins and RNAs traffic through the nuclear pore complexes, enabled by the interacting activities...

Friction forces on phase transition fronts

International Nuclear Information System (INIS)

Mégevand, Ariel

2013-01-01

In cosmological first-order phase transitions, the microscopic interaction of the phase transition fronts with non-equilibrium plasma particles manifests itself macroscopically as friction forces. In general, it is a nontrivial problem to compute these forces, and only two limits have been studied, namely, that of very slow walls and, more recently, ultra-relativistic walls which run away. In this paper we consider ultra-relativistic velocities and show that stationary solutions still exist when the parameters allow the existence of runaway walls. Hence, we discuss the necessary and sufficient conditions for the fronts to actually run away. We also propose a phenomenological model for the friction, which interpolates between the non-relativistic and ultra-relativistic values. Thus, the friction depends on two friction coefficients which can be calculated for specific models. We then study the velocity of phase transition fronts as a function of the friction parameters, the thermodynamic parameters, and the amount of supercooling

The IAEA Nuclear Security Programme Combating Nuclear Terrorism

International Nuclear Information System (INIS)

2010-01-01

Discusses the four threats of nuclear terrorism,which are theft of a nuclear weapon, theft of material to make an improvised nuclear explosive device,theft of other radioactive material for an Radiological dispersal device and sabotage of a facility or transport. The IAEA Nuclear Security programme combating Nuclear Terrorism therefore adopts a comprehensive approach. The programme addresses the need to cover nuclear and other radioactive materials, nuclear facilities and transports, non-nuclear, medical and industrial applications of sources

Nuclear power and the nuclear fuel cycle

Energy Technology Data Exchange (ETDEWEB)

NONE

1976-07-01

The IAEA is organizing a major conference on nuclear power and the nuclear fuel cycle, which is to be held from 2 to 13 May 1977 in Salzburg, Austria. The programme for the conference was published in the preceding issue of the IAEA Bulletin (Vol.18, No. 3/4). Topics to be covered at the conference include: world energy supply and demand, supply of nuclear fuel and fuel cycle services, radioactivity management (including transport), nuclear safety, public acceptance of nuclear power, safeguarding of nuclear materials, and nuclear power prospects in developing countries. The articles in the section that follows are intended to serve as an introduction to the topics to be discussed at the Salzburg Conference. They deal with the demand for uranium and nuclear fuel cycle services, uranium supplies, a computer simulation of regional fuel cycle centres, nuclear safety codes, management of radioactive wastes, and a pioneering research project on factors that determine public attitudes toward nuclear power. It is planned to present additional background articles, including a review of the world nuclear fuel reprocessing situation and developments in the uranium enrichment industry, in future issues of the Bulletin. (author)

Report of “the 2013 international forum on peaceful use of nuclear energy, nuclear non-proliferation and nuclear security. Ensuring nuclear non-proliferation and nuclear security of nuclear fuel cycle options in consideration of the accident at TEPCO's Fukushima Daiichi Nuclear Power Station”

International Nuclear Information System (INIS)

Yamamura, Tsukasa; Suda, Kazunori; Tomikawa, Hirofumi; Suzuki, Mitsutoshi; Kuno, Yusuke; Mochiji, Toshiro

2014-03-01

The Japan Atomic Energy Agency (JAEA) held “International Forum on Peaceful Use of Nuclear Energy, Nuclear Non-proliferation and Nuclear Security – Ensuring Nuclear Non-Proliferation and Nuclear Security of Nuclear Fuel Cycle Options in consideration of the Accident at TEPCO's Fukushima Daiichi Nuclear Power Station –” on 3 and 4 December 2013, with the Japan Institute of International Affairs (JIIA) and School of Engineering, The University of Tokyo, as co-hosts. In the Forum, officials from Japan, the United States, France and International Atomic Energy Agency (IAEA) explained their efforts regarding peaceful use of nuclear energy and nuclear non-proliferation. Discussion was made in two panels, entitled “Nuclear non-proliferation and nuclear security measures of nuclear fuel cycle options in consideration of the Accident at TEPCO's Fukushima Daiichi Nuclear Power Station” and “Roles of safeguards and technical measures for ensuring nuclear non-proliferation for nuclear fuel cycle options”. In the first panel based on the implications of the Accident at TEPCO's Fukushima Daiichi Nuclear Power Station on the domestic and global nuclear energy use and increased interest in the back end of nuclear fuel cycle, discussion was made on nuclear non-proliferation and nuclear security challenges on both fuel cycle options from the policy and institutional viewpoints whereas in the second panel the roles of safeguards and proliferation resistant nuclear technology including plutonium burning technology in ensuring nuclear non-proliferation and nuclear security in the back end of nuclear fuel cycle were discussed. Officials and experts from Japan, IAEA, the United States, France and Republic of Korea participated in the panel and made contributions to active discussion. This report includes abstracts of keynote speeches, summaries of two panel discussions and materials of the presentations in the forum. The editors take full responsibility for the wording

The Wrath of Image

DEFF Research Database (Denmark)

Isar, Nicoletta

2013-01-01

Belting’s line of thinking and his anthropology of image, the article approaches the subject in connection with the essence of anthropos and its substance – to deinon, that is, the awesome and duplicitary power of man given by technè. The first part is devoted to prometheia, the mythical origins of art...... – the transgenic. The transgenic shows how by closing the gap between human and transhuman, transvisuality radically departs from the classical models of ontology and visuality emerging into a new field. I call it transvisuality in extremis, the transhuman facet of anthropogony. This is the new staging...

The nuclear arsenals and nuclear disarmament.

Science.gov (United States)

Barnaby, F

1998-01-01

Current world stockpiles of nuclear weapons and the status of treaties for nuclear disarmament and the ultimate elimination of nuclear weapons are summarised. The need for including stockpiles of civil plutonium in a programme for ending production and disposing of fissile materials is emphasized, and the ultimate difficulty of disposing of the last few nuclear weapons discussed.

Nuclear power generation and nuclear non-proliferation

International Nuclear Information System (INIS)

Rathjens, G.

1979-01-01

The main points existing between nuclear energy development and nuclear non-proliferation policy are reviewed. The solar energy and other energy will replace for nuclear fission energy in the twenty first century, but it may not occur in the first half, and the structure has to be established to continue the development of nuclear fission technology, including breeder reactor technology. In the near future, it should be encouraged to use advanced thermal reactors if they are economic and operated with safety. Miserable results may be created in the worldwide scale, if a serious accident occurs anywhere or nuclear power reactors are utilized for military object. It is estimated to be possible to develop the ability of manufacturing nuclear weapons within two or three years in the countries where the industry is highly developed so as to generate nuclear power. It is also difficult to take measures so that nuclear power generation does not increase nuclear proliferation problems, and it is necessary to mitigate the motive and to establish the international organization. Concensus exists that as the minimum security action, the storage and transportation of materials, which can be directly utilized for nuclear weapons, should be decided by the international system. The most portions of sensitive nuclear fuel cycle should be put under the international management, as far as possible. This problem is discussed in INFCE. Related to the nuclear nonproliferation, the difference of policy in fuel cycle problems between USA and the other countries, the enrichment of nuclear fuel material, especially the reasons to inhibit the construction of additional enrichment facilities, nuclear fuel reprocessing problems, radioactive waste disposal, plutonium stock and plutonium recycle problems are reviewed. (Nakai, Y.)

A study of vorticity formation in high energy nuclear collisions

Energy Technology Data Exchange (ETDEWEB)

Becattini, F. [Universita di Firenze, Dipartimento di Fisica e Astronomia, Sesto F.no (Firenze) (Italy); INFN, Sezione di Firenze, Sesto F.no (Firenze) (Italy); Inghirami, G. [Universita di Firenze, Dipartimento di Fisica e Astronomia, Sesto F.no (Firenze) (Italy); Johann Wolfgang Goethe University, Frankfurt Institute for Advanced Studies (FIAS), Frankfurt am Main (Germany); Rolando, V.; Pagliara, G. [Universita di Ferrara, Dipartimento di Fisica e Scienze della Terra, Ferrara (Italy); INFN, Sezione di Ferrara, Ferrara (Italy); Beraudo, A.; De Pace, A.; Nardi, M. [INFN, Sezione di Torino, Turin (Italy); Del Zanna, L. [Universita di Firenze, Dipartimento di Fisica e Astronomia, Sesto F.no (Firenze) (Italy); INFN, Sezione di Firenze, Sesto F.no (Firenze) (Italy); INAF, Osservatorio Astrofisico di Arcetri, Florence (Italy); Chandra, V. [Indian Institute of Technology Gandhinagar, Ahmedabad, Gujrat (India)

2015-09-15

We present a quantitative study of vorticity formation in peripheral ultrarelativistic heavy-ion collisions at √(s{sub NN}) = 200 GeV by using the ECHO-QGP numerical code, implementing relativistic dissipative hydrodynamics in the causal Israel-Stewart framework in 3 + 1 dimensions with an initial Bjorken flow profile. We consider different definitions of vorticity which are relevant in relativistic hydrodynamics. After demonstrating the excellent capabilities of our code, which proves to be able to reproduce Gubser flow up to 8 fm/c, we show that, with the initial conditions needed to reproduce the measured directed flow in peripheral collisions corresponding to an average impact parameter b = 11.6 fm and with the Bjorken flow profile for a viscous Quark Gluon Plasma with η/s = 0.1 fixed, a vorticity of the order of some 10{sup -2} c/fm can develop at freeze-out. The ensuing polarization of Λ baryons does not exceed 1.4 % at midrapidity. We show that the amount of developed directed flow is sensitive to both the initial angular momentum of the plasma and its viscosity. (orig.)

Relativistic quantum nonlocality for the three-qubit Greenberger-Horne-Zeilinger state

International Nuclear Information System (INIS)

Moradi, Shahpoor

2008-01-01

Lorentz transformation of the three-qubit Greenberger-Horne-Zeilinger (GHZ) state is studied. Also we obtain the relativistic spin joint measurement for the transformed state. Using these results it is shown that Bell's inequality is maximally violated for the three-qubit GHZ state in the relativistic regime. For ultrarelativistic particles we obtain the critical value for boost speed, which Bell's inequality is not violated for velocities smaller than this value. We also show that in the ultrarelativistic limit Bell's inequality is maximally violated for the GHZ state

Nuclear re-think [The case for nuclear energy

International Nuclear Information System (INIS)

Moore, P.

2006-01-01

In the early 1970s, Patrick Moore, a co-founder of Greenpeace, believed that nuclear energy was synonymous with nuclear holocaust. Thirty years on, his views have changed because nuclear energy is the only non-greenhouse-gas-emitting power source that can effectively replace fossil fuels while satisfying the world's increasing demand for energy. Today, 441 nuclear plants operating globally avoid the release of nearly 3 billion tonnes of CO 2 emissions annually-the equivalent of the exhaust from more than 428 million cars. Concerns associated with nuclear energy are discussed including costs of nuclear energy, safety of nuclear plants, radioactive waste management, vulnerability of nuclear plants to terrorist attacks and diversion of nuclear fuel for weaponization. It is concluded that nuclear energy is the best way to produce safe, clean, reliable baseload electricity, and will play a key role in achieving global energy security. With climate change at the top of the international agenda, we must all do our part to encourage a nuclear energy renaissance

Nuclear war nuclear proliferation and their consequences

International Nuclear Information System (INIS)

Aga Khan, Sadruddin

1986-01-01

The paper concerns the proceedings of a conference hosted by the Groupe de Bellerive to explore and discuss the implications for humanity of nuclear war, nuclear proliferation and their consequences, Geneva 1985. The conference was divided into five sessions, headed by the subject titles: the nuclear non-proliferation treaty (NPT) and its future, the spread of nuclear weapons among nations, global effects of a nuclear war, the nuclear arms race and arms control, the NPT and its future. Twenty eight papers were presented in the five sessions. (UK)

Nuclear Inter Jura '91: nuclear law and nuclear energy for the future

International Nuclear Information System (INIS)

1992-01-01

The 1991 congress of the International Nuclear Law Association took as its subject Nuclear Law and Nuclear Energy for the future. As well as individual reports, there were four sessions each covering the report of one or more working groups. The first session investigated licensing and decommissioning, while the second focussed on insurance and liability. The third session was devoted to nuclear supply and commerce at an international level. Finally radiological protection and nuclear waste management was discussed in the fourth session. (UK)

Nuclear energy - some aspects; Energia nuclear - alguns aspectos

Energy Technology Data Exchange (ETDEWEB)

Bandeira, Fausto de Paula Menezes

2005-05-15

This work presents a brief history of research and development concerning to nuclear technology worldwide and in Brazil, also information about radiations and radioactive elements as well; the nuclear technology applications; nuclear reactor types and functioning of thermonuclear power plants; the number of existing nuclear power plants; the nuclear hazards occurred; the national fiscalization of nuclear sector; the Brazilian legislation in effect and the propositions under proceduring at House of Representatives related to the nuclear energy.

First results from ALICE on anisotropic flow at Run 2 at LHC

CERN Multimedia

CERN. Geneva

2016-01-01

The goal of studies with relativistic heavy-ion collisions is to investigate the Quark-Gluon Plasma (QGP), a state of matter where quarks and gluons move freely over distances large in comparison to the typical size of a hadron. The exploration of QGP properties has broken new ground with the recent heavy-ion collisions from Run 2 operations at Large Hadron Collider, at the highest energies to date. The ALICE Collaboration has made the first observation of anisotropic flow of charged particles in lead-lead collisions at the record breaking energy of 5.02 TeV per nucleon pair. The talk presents these new results and discusses how they further enlighten the properties of matter produced in ultrarelativistic nuclear collisions.

High transverse momentum resonance production in Pb-Pb, pp and p-Pb collisions at LHC

CERN Document Server

Nayak, Kishora

2015-01-01

Resonance production in heavy-ion collisions is expected to be a sensitive probe to the proper- ties of strongly interacting matter produced in such collisions. The production of resonances at high transverse momentum will help us to understand the mechanism of particle production and parton energy loss in the medium formed in ultra-relativistic heavy-ion collisions. We report the measurements of K ∗ 0 ( τ ∼ 4 fm/ c ) and φ ( τ ∼ 42 fm/ c ) production at high transverse momen- tum in pp, p–Pb and Pb–Pb collisions at LHC energies and nuclear modification factors. These measurements are compared to corresponding results for the other produced hadrons like charged kaons and protons. Some aspects of resonance production and particle production in general are discussed.

Clandestine nuclear trade and the threat of nuclear terrorism

International Nuclear Information System (INIS)

Spector, L.S.

1987-01-01

The nuclear netherworld may ultimately contribute to the danger of nuclear terrorism in at least three ways. First, as national governments exploit this underground market and nuclear weapons spread to additional states, the possibility that terrorists will gain access to them will grow. Such weapons in nuclear threshold countries are likely to be more vulnerable to terrorist seizure than they are in today's more advanced nuclear weapons states. Second, terrorist groups might seek to exploit the nuclear gray market themselves, using the same subterfuges that national governments use. Although in today's nuclear netherworld, subnational groups cannot obtain nuclear arms or nuclear weapons material and cannot hope to build the complex installations needed to produce the latter, they might be able to engage in a form of barter with sympathetic emerging nuclear states (for example, offering raw materials or needed nuclear hardware in return for nuclear weapons material. Finally, there is always the risk that nuclear arms or nuclear weapon materials will someday become available on the nuclear black market. There is evidence indicating that terrorist organizations might well be interested in acquiring such items. Understanding underground nuclear commerce in its current form is essential to prevent such future dangers

The threat of nuclear terrorism: Nuclear weapons or other nuclear explosive devices

International Nuclear Information System (INIS)

Maerli, Morten Bremer

2001-01-01

Full text: Conventional weaponry and tactics are likely to remain the primary terrorist means for a definitive majority of sub-national groups. No non-state actors have ever deployed or used a nuclear device. However, recent developments in international terrorism may point in the direction of future terrorist uses of weapons of mass destruction, including nuclear devices. Some terrorist groups with a high international profile have showed disturbing interests in acquiring nuclear weapon capabilities. As the 'terrorist nuclear weapon standards' are likely to be lower than the strict requirements for traditional state nuclear weapons, technical barriers should not be considered sufficient to avoid future nuclear terrorist violence. Preventing any extremist group from achieving their goals of large-scale nuclear killing is likely best done by preventing the access to fissile materials through state compliances to rigorous standards of Material Protection, Control and Accountability (MPC and A). (author)

Chinese nuclear insurance and Chinese nuclear insurance pool

International Nuclear Information System (INIS)

Gong Zhiqi

2000-01-01

Chinese Nuclear Insurance Started with Daya Bay Nuclear Power Station, PICC issued the insurance policy. Nuclear insurance cooperation between Chinese and international pool's organizations was set up in 1989. In 1996, the Chinese Nuclear Insurance Pool was prepared. The Chinese Nuclear Insurance Pool was approved by The Chinese Insurance Regulatory Committee in May of 1999. The principal aim is to centralize maximum the insurance capacity for nuclear insurance from local individual insurers and to strengthen the reinsurance relations with international insurance pools so as to provide the high quality insurance service for Chinese nuclear industry. The Member Company of Chinese Nuclear Pool and its roles are introduced in this article

Nuclear generation cost and nuclear research development fund

International Nuclear Information System (INIS)

Kim, S. S.; Song, G. D.

2000-01-01

The main objective of this study is to analyze the effects of nuclear R and D fund to nuclear generation cost and to assess the adaptability of fund size through the comparison with the nuclear research fund in Japan. It was estimated that nuclear R and D fund increased the average annual unit cost of nuclear power generation by 1.14 won/kWh. When the size of nuclear R and D fund is compared with that in Japan, this study suggests that the current nuclear R and D fund should be largely increased taking into consideration the ratio of R and D fund to nuclear generation

11-th International conference Nuclear power safety and nuclear education - 2009. Abstracts. Part 1. Session: Safety of nuclear technology; Innovative nuclear systems and fuel cycle; Nuclear knowledge management

International Nuclear Information System (INIS)

2009-01-01

The book includes abstracts of the 11-th International conference Nuclear power safety and nuclear education - 2009 (29 Sep - 2 Oct, 2009, Obninsk). Problems of safety of nuclear technology are discussed, innovative nuclear systems and fuel cycles are treated. Abstracts on professional education for nuclear power and industry are presented. Nuclear knowledge management are discussed

Degenerate pressure driven modified nucleus-acoustic waves in degenerate plasmas

Science.gov (United States)

Mamun, A. A.

2018-02-01

The existence of degenerate pressure driven modified nucleus-acoustic (DPDMNA) waves propagating in a cold degenerate quantum plasma (DQP) system [containing cold inertialess degenerate electron species (DES), cold inertial non-degenerate light nucleus species (LNS), and stationary heavy nucleus species (HNS)] is predicted for the first time. The DPDMNA waves (in which the mass density of the cold LNS provides the inertia and the cold inertialess DES gives rise to the restoring force) are new since they completely disappear if the degenerate pressure of the cold DES is neglected. It is found that the phase speed (Vp) of the DPDMNA waves decreases with the rise of the charge number density of the stationary HNS for both non-relativistic and ultra-relativistic DES, and that the ultra-relativistic DES does not have any effect on Vp when β = 1, where β = Λc/Λe with Λ e = ne 0 - 1 / 3 being the average inter-electron distance in the DQP system and Λc being the constant (˜10-10 cm) for the DES. However, the ultra-relativistic DES does have quite a significant effect on Vp for β ≫ 1 and β ≪ 1, and the ultra-relativistic effect significantly enhances (reduces) Vp for β ≫ 1 (β ≪ 1). The DPDMNA waves and their dispersion properties are expected to be useful in understanding the basic features of the electrostatic perturbation mode in space and laboratory DQP systems.

Nuclear 101, a course on the nuclear sector for workers in the nuclear sector

Energy Technology Data Exchange (ETDEWEB)

Donev, J.M.K.C., E-mail: jason.donev@ucalgary.ca [Univ. of Calgary, Calgary, AB (Canada); Boreham, D.; Day, S., E-mail: boreham@mcmaster.ca, E-mail: dayse@mcmaster.ca [McMaster Univ., Hamilton, ON (Canada); Dranga, R.; Krasznai, J.; Matthews, R.; Whitlock, J. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

2014-07-01

People who work in the nuclear science and technology community are often called upon in social situations to answer questions about the nuclear industry outside their area of direct expertise. In 2012 the Canadian Nuclear Society created 'Nuclear 101', a two-day general-level course to provide more information on the nuclear sector to people who are part of the nuclear science and technology community. This paper will discuss how Nuclear 101 aids public outreach discussions and the lessons learned after two years of operation, and will look at future directions for the course. (author)

Nuclear 101, a course on the nuclear sector for workers in the nuclear sector

International Nuclear Information System (INIS)

Donev, J.M.K.C.; Boreham, D.; Day, S.; Dranga, R.; Krasznai, J.; Matthews, R.; Whitlock, J.

2014-01-01

People who work in the nuclear science and technology community are often called upon in social situations to answer questions about the nuclear industry outside their area of direct expertise. In 2012 the Canadian Nuclear Society created 'Nuclear 101', a two-day general-level course to provide more information on the nuclear sector to people who are part of the nuclear science and technology community. This paper will discuss how Nuclear 101 aids public outreach discussions and the lessons learned after two years of operation, and will look at future directions for the course. (author)

Nuclear physics for nuclear fusion

International Nuclear Information System (INIS)

Li Xingzhong; Liu Bin; Wei Qingming; Ren Xianzhe

2004-01-01

The D-T fusion cross-section is calculated using quantum mechanics with the model of square nuclear potential well and Coulomb potential barrier. The agreement between ENDF data and the theoretically calculated results is well in the range of 0.2-280 keV. It shows that the application of Breit-Wigner formula is not suitable for the case of the light nuclei fusion reaction. When this model is applied to the nuclear reaction between the charged particles confined in a lattice, it explains the 'abnormal phenomena'. It implies a prospect of nuclear fusion energy without strong nuclear radiations

New nuclear projects in the world. Sustainable Nuclear Energy; Nuevos proyectos nucleares en el mundo. energia nuclear sostenible

Energy Technology Data Exchange (ETDEWEB)

Leon, P. T.

2011-07-01

Nuclear power has experienced a major boom in the last few years, primarily because it is a non-CO{sub 2} emitting energy source, it can be produced at competitive costs and it can boost a country's security of supply. there are still two issues to be addressed in relation to the currently used technologies: the degree to which the energy content of nuclear fuel is used, and wastes. A solution to both these aspects would ut nuclear power in the category of sustainable energy. The article provides details on current nuclear plans in the wold, the impact of the Fukushima accident on different countries nuclear plans and the European initiatives for sustainable nuclear energy development. (Author)

Nuclear disarmament and peaceful nuclear technology

International Nuclear Information System (INIS)

Taylor, T.B.

1989-01-01

According to the author, it remains to be seen whether nuclear disarmament can reduce the risks of nuclear war sufficiently for the residual risks to be acceptable to a majority of the world's population, while at the same time vigorous growth in the world's dependence on nuclear energy for peaceful purposes continues. This paper discusses how use of nuclear materials from dismantled weapons as fuel for peaceful purposes may help progress to be made towards that goal, by stimulating considerable improvements in the effectiveness of arrangements for preventing diversion of the materials from peaceful to military purposes, while at the same time eliminating large numbers of nuclear weapons

Laser-Driven Ultra-Relativistic Plasmas - Nuclear Fusion in Coulomb Shock Waves, Rouge Waves, and Background Matter

Science.gov (United States)

2015-05-05

the time-scale of Big Bang , and the most significant time scale posts on the road to it. In his work [2], this PI also proposed specific mechanisms and...recently: (1) fully QED/relativistic theory of light pressure of 15.  SUBJECT TERMS plasmas Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39.18...large moving man-made objects in the ocean. A 2D and 3D expansion of the theory may need to be developed for other potential appli- cations of G

Nuclear power and nuclear safety 2008

International Nuclear Information System (INIS)

Lauritzen, B.; Oelgaard, P.L.; Kampmann, D.

2009-06-01

The report is the fifth report in a series of annual reports on the international development of nuclear power production, with special emphasis on safety issues and nuclear emergency preparedness. The report is written in collaboration between Risoe DTU and the Danish Emergency Management Agency. The report for 2008 covers the following topics: status of nuclear power production, regional trends, reactor development, safety related events of nuclear power, and international relations and conflicts. (LN)

Report of the international forum on nuclear energy, nuclear non-proliferation and nuclear security. Measures to ensure nuclear non-proliferation and nuclear security for the back end of nuclear fuel cycle and regional cooperation in Asia

International Nuclear Information System (INIS)

Tazaki, Makiko; Yamamura, Tsukasa; Suzuki, Mitsutoshi; Kuno, Yusuke; Mochiji, Toshiro

2013-03-01

The Japan Atomic Energy Agency (JAEA) held 'International Forum on Nuclear Energy, Nuclear Non-proliferation and Nuclear Security - Measures to ensure nuclear non-proliferation and nuclear security for the back end of nuclear fuel cycle and regional cooperation in Asia-' on 12 and 13 December 2012, co-hosted by the Japan Institute of International Affairs (JIIA) and School of Engineering, The University of Tokyo. In the forum, keynote speakers from Japan, International Atomic Energy Agency (IAEA), the U.S., France and Republic of Korea (ROK), respectively explained their efforts regarding peaceful use of nuclear energy and nuclear non-proliferation. In two panel discussions, entitled 'Measures to ensure nuclear non-proliferation and nuclear security of nuclear fuel cycle back end' and 'Measures to ensure nuclear non-proliferation and nuclear security for nuclear energy use in the Asian region and a multilateral cooperative framework', active discussions were made among panelists from Japan, IAEA, the U.S., France, ROK, Russia and Kazakhstan. This report includes abstracts of keynote speeches, summaries of two panel discussions and materials of the presentations in the forum. The editors take full responsibility for the wording and content of this report except presentation materials. (author)

Nuclear topics

International Nuclear Information System (INIS)

Lukner, C.

1982-07-01

The pamphlet touches on all aspects of nuclear energy, from the world energy demands and consumption, the energy program of the Federal Government, nuclear power plants in the world, nuclear fusion, nuclear liability up to the nuclear fuel cycle and the shutdown of nuclear power plants. (HSCH) [de

Nuclear proliferation and the near-nuclear countries

International Nuclear Information System (INIS)

Marwah, O.; Schulz, A.

1975-01-01

The process of nuclear proliferation and its consequences for the international political system is examined by focusing on the issues in the nuclear-strategic debate that divide first and second order states. Information is included on: the US-USSR arms race; SALT agreement; the Non-Proliferation Treaty; the nuclear aspirations and policies of India, Middle Eastern countries, South Africa, Japan, Brazil, and Argentina; and assessment of the risks related to the nuclear fuel cycle and nuclear weapons

Redefining interrelationship between nuclear safety, nuclear security and safeguards

International Nuclear Information System (INIS)

Irie, Kazutomo

2011-01-01

Since the beginning of this century, the so-called 3Ss (Nuclear Safety, Nuclear Security and Safeguards) have become major regulatory areas for peaceful uses of nuclear energy. The importance of the 3Ss is now emphasized to countries which are newly introducing nuclear power generation. However, as role models for those newcomers, existing nuclear power countries are also required to strengthen their regulatory infrastructure for the 3Ss. In order to rationalize the allocation of regulatory resources, interrelationship of the 3Ss should be investigated. From the viewpoint of the number of the parties concerned in regulation, nuclear security is peculiar with having 'aggressors' as the third party. From the viewpoint of final goal of regulation, nuclear security in general and safeguards share the goal of preventing non-peaceful uses of nuclear energy, though the goal of anti-sabotage within nuclear security is rather similar to nuclear safety. As often recognized, safeguards are representative of various policy tools for nuclear non-proliferation. Strictly speaking, it is not safeguards as a policy tool but nuclear non-proliferation as a policy purpose that should be parallel to other policy purposes (nuclear safety and nuclear security). That suggests 'SSN' which stands for Safety, Security and Non-proliferation is a better abbreviation rather than 3Ss. Safeguards as a policy tool should be enumerated along with nuclear safety regulation, nuclear security measures and trade controls on nuclear-related items. Trade controls have been playing an important role for nuclear non-proliferation. These policy tools can be called 'SSST' in which Trade controls are also emphasized along with Safety regulation, Security measures and Safeguards. Recently, it becomes quite difficult to clearly demarcate these policy tools. As nuclear security concept is expanding, the denotation of nuclear security measures is also expanding. Nuclear security measures are more and more

Model dependence of isospin sensitive observables at high densities

Energy Technology Data Exchange (ETDEWEB)

Guo, Wen-Mei [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); School of Science, Huzhou Teachers College, Huzhou 313000 (China); Yong, Gao-Chan, E-mail: yonggaochan@impcas.ac.cn [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190 (China); Wang, Yongjia [School of Science, Huzhou Teachers College, Huzhou 313000 (China); School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); Li, Qingfeng [School of Science, Huzhou Teachers College, Huzhou 313000 (China); Zhang, Hongfei [School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000 (China); State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190 (China); Zuo, Wei [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190 (China)

2013-10-07

Within two different frameworks of isospin-dependent transport model, i.e., Boltzmann–Uehling–Uhlenbeck (IBUU04) and Ultrarelativistic Quantum Molecular Dynamics (UrQMD) transport models, sensitive probes of nuclear symmetry energy are simulated and compared. It is shown that neutron to proton ratio of free nucleons, π{sup −}/π{sup +} ratio as well as isospin-sensitive transverse and elliptic flows given by the two transport models with their “best settings”, all have obvious differences. Discrepancy of numerical value of isospin-sensitive n/p ratio of free nucleon from the two models mainly originates from different symmetry potentials used and discrepancies of numerical value of charged π{sup −}/π{sup +} ratio and isospin-sensitive flows mainly originate from different isospin-dependent nucleon–nucleon cross sections. These demonstrations call for more detailed studies on the model inputs (i.e., the density- and momentum-dependent symmetry potential and the isospin-dependent nucleon–nucleon cross section in medium) of isospin-dependent transport model used. The studies of model dependence of isospin sensitive observables can help nuclear physicists to pin down the density dependence of nuclear symmetry energy through comparison between experiments and theoretical simulations scientifically.

Nuclear

International Nuclear Information System (INIS)

2014-01-01

This document proposes a presentation and discussion of the main notions, issues, principles, or characteristics related to nuclear energy: radioactivity (presence in the environment, explanation, measurement, periods and activities, low doses, applications), fuel cycle (front end, mining and ore concentration, refining and conversion, fuel fabrication, in the reactor, back end with reprocessing and recycling, transport), the future of the thorium-based fuel cycle (motivations, benefits and drawbacks), nuclear reactors (principles of fission reactors, reactor types, PWR reactors, BWR, heavy-water reactor, high temperature reactor of HTR, future reactors), nuclear wastes (classification, packaging and storage, legal aspects, vitrification, choice of a deep storage option, quantities and costs, foreign practices), radioactive releases of nuclear installations (main released radio-elements, radioactive releases by nuclear reactors and by La Hague plant, gaseous and liquid effluents, impact of releases, regulation), the OSPAR Convention, management and safety of nuclear activities (from control to quality insurance, to quality management and to sustainable development), national safety bodies (mission, means, organisation and activities of ASN, IRSN, HCTISN), international bodies, nuclear and medicine (applications of radioactivity, medical imagery, radiotherapy, doses in nuclear medicine, implementation, the accident in Epinal), nuclear and R and D (past R and D programmes and expenses, main actors in France and present funding, main R and D axis, international cooperation)

University of Maryland annual progress report

International Nuclear Information System (INIS)

Mignerey, A.C.

1995-02-01

The two main areas of research of intermediate energy heavy-ion reactions and ultrarelativistic heavy-ion reactions are presented in this report. Among the intermediate energy research topics were 129 Xe reactions, calibration of the plastic elements in the Maryland Forward Array, and a cluster recognition model for treating BUU-generated distributions. The ultrarelativistic energy research program included the LED system for the NMA (New Multiplicity Array) in E866 at BNL AGS, the E866 collaboration (antiprotons and NMA), and PHOBOS magnet work. 139 La reactions were also studied

University of Maryland annual progress report

Energy Technology Data Exchange (ETDEWEB)

Mignerey, A.C.

1995-02-01

The two main areas of research of intermediate energy heavy-ion reactions and ultrarelativistic heavy-ion reactions are presented in this report. Among the intermediate energy research topics were {sup 129}Xe reactions, calibration of the plastic elements in the Maryland Forward Array, and a cluster recognition model for treating BUU-generated distributions. The ultrarelativistic energy research program included the LED system for the NMA (New Multiplicity Array) in E866 at BNL AGS, the E866 collaboration (antiprotons and NMA), and PHOBOS magnet work. {sup 139}La reactions were also studied.

Nuclear rights - nuclear wrongs

Energy Technology Data Exchange (ETDEWEB)

Paul, E.F.; Miller, F.D.; Paul, J.; Ahrens, J.

1986-01-01

This book contains 11 selections. The titles are: Three Ways to Kill Innocent Bystanders: Some Conundrums Concerning the Morality of War; The International Defense of Liberty; Two Concepts of Deterrence; Nuclear Deterrence and Arms Control; Ethical Issues for the 1980s; The Moral Status of Nuclear Deterrent Threats; Optimal Deterrence; Morality and Paradoxical Deterrence; Immoral Risks: A Deontological Critique of Nuclear Deterrence; No War Without Dictatorship, No Peace Without Democracy: Foreign Policy as Domestic Politics; Marxism-Leninism and its Strategic Implications for the United States; Tocqueveille War.

White Paper on Nuclear Astrophysics and Low Energy Nuclear Physics - Part 1. Nuclear Astrophysics

Energy Technology Data Exchange (ETDEWEB)

Arcones, Almudena [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Escher, Jutta E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Others, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2016-04-04

This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21 - 23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9 - 10, 2012 Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). The white paper is furthermore informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12 - 13, 2014. In summary we find that nuclear astrophysics is a modern and vibrant field addressing fundamental science questions at the intersection of nuclear physics and astrophysics. These questions relate to the origin of the elements, the nuclear engines that drive life and death of stars, and the properties of dense matter. A broad range of nuclear accelerator facilities, astronomical observatories, theory efforts, and computational capabilities are needed. With the developments outlined in this white paper, answers to long-standing key questions are well within reach in the coming decade.

White paper on nuclear astrophysics and low energy nuclear physics Part 1: Nuclear astrophysics

International Nuclear Information System (INIS)

Arcones, Almudena; Bardayan, Dan W.

2016-01-01

This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It also summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21–23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9–10, 2012 Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). Our white paper is informed informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12–13, 2014. In summary we find that nuclear astrophysics is a modern and vibrant field addressing fundamental science questions at the intersection of nuclear physics and astrophysics. These questions relate to the origin of the elements, the nuclear engines that drive life and death of stars, and the properties of dense matter. A broad range of nuclear accelerator facilities, astronomical observatories, theory efforts, and computational capabilities are needed. Answers to long standing key questions are well within reach in the coming decade because of the developments outlined in this white paper.

Nuclear Medicine

Science.gov (United States)

... Parents/Teachers Resource Links for Students Glossary Nuclear Medicine What is nuclear medicine? What are radioactive tracers? ... funded researchers advancing nuclear medicine? What is nuclear medicine? Nuclear medicine is a medical specialty that uses ...

BS degree in nuclear engineering or a nuclear option

International Nuclear Information System (INIS)

Williams on, T.G.

1988-01-01

Many nuclear engineering educators are concerned about the health of nuclear engineering academic departments. As part of a review of the BS nuclear engineering degree program at the University of Virginia, the authors surveyed several local utilities with operating nuclear plants about their needs for nuclear engineering graduates. The perception of many of the utility executives about a nuclear engineering degree and about a nuclear option in another engineering curriculum does not agree with the way the authors view these two degrees. The responses to two of the survey questions were of particular interest: (1) does your company have a preference between nuclear engineering graduates and graduates in other fields with a nuclear option? (2) what do you consider to be a minimum level of education in nuclear engineering for a nuclear option in mechanical engineering? All of the four utilities that were surveyed stated a preference for mechanical or electrical engineers with a nuclear option, although two indicated that there are certain jobs for which a nuclear engineering graduate is desired

76 FR 19148 - Entergy Nuclear Operations, Inc., Entergy Nuclear Vermont Yankee, LLC, Vermont Yankee Nuclear...

Science.gov (United States)

2011-04-06

... NUCLEAR REGULATORY COMMISSION [Docket No. 50-271; License No. DPR-28; NRC-2011-0074] Entergy Nuclear Operations, Inc., Entergy Nuclear Vermont Yankee, LLC, Vermont Yankee Nuclear Power Station..., ``Requests for Action under this Subpart,'' the U.S. Nuclear Regulatory Commission (NRC) take action with...

Quantum nuclear pasta and nuclear symmetry energy

Science.gov (United States)

Fattoyev, F. J.; Horowitz, C. J.; Schuetrumpf, B.

2017-05-01

Complex and exotic nuclear geometries, collectively referred to as "nuclear pasta," are expected to appear naturally in dense nuclear matter found in the crusts of neutron stars and supernovae environments. The pasta geometries depend on the average baryon density, proton fraction, and temperature and are critically important in the determination of many transport properties of matter in supernovae and the crusts of neutron stars. Using a set of self-consistent microscopic nuclear energy density functionals, we present the first results of large scale quantum simulations of pasta phases at baryon densities 0.03 ≤ρ ≤0.10 fm-3 , proton fractions 0.05 ≤Yp≤0.40 , and zero temperature. The full quantum simulations, in particular, allow us to thoroughly investigate the role and impact of the nuclear symmetry energy on pasta configurations. We use the Sky3D code that solves the Skyrme Hartree-Fock equations on a three-dimensional Cartesian grid. For the nuclear interaction we use the state-of-the-art UNEDF1 parametrization, which was introduced to study largely deformed nuclei, hence is suitable for studies of the nuclear pasta. Density dependence of the nuclear symmetry energy is simulated by tuning two purely isovector observables that are insensitive to the current available experimental data. We find that a minimum total number of nucleons A =2000 is necessary to prevent the results from containing spurious shell effects and to minimize finite size effects. We find that a variety of nuclear pasta geometries are present in the neutron star crust, and the result strongly depends on the nuclear symmetry energy. The impact of the nuclear symmetry energy is less pronounced as the proton fractions increase. Quantum nuclear pasta calculations at T =0 MeV are shown to get easily trapped in metastable states, and possible remedies to avoid metastable solutions are discussed.

Two-stage nuclear refrigeration with enhanced nuclear moments

International Nuclear Information System (INIS)

Hunik, R.

1979-01-01

Experiments are described in which an enhanced nuclear system is used as a precoolant for a nuclear demagnetisation stage. The results show the promising advantages of such a system in those circumstances for which a large cooling power is required at extremely low temperatures. A theoretical review of nuclear enhancement at the microscopic level and its macroscopic thermodynamical consequences is given. The experimental equipment for the implementation of the nuclear enhanced refrigeration method is described and the experiments on two-stage nuclear demagnetisation are discussed. With the nuclear enhanced system PrCu 6 the author could precool a nuclear stage of indium in a magnetic field of 6 T down to temperatures below 10 mK; this resulted in temperature below 1 mK after demagnetisation of the indium. It is demonstrated that the interaction energy between the nuclear moments in an enhanced nuclear system can exceed the nuclear dipolar interaction. Several experiments are described on pulsed nuclear magnetic resonance, as utilised for thermometry purposes. It is shown that platinum NMR-thermometry gives very satisfactory results around 1 mK. The results of experiments on nuclear orientation of radioactive nuclei, e.g. the brute force polarisation of 95 NbPt and 60 CoCu, are presented, some of which are of major importance for the thermometry in the milli-Kelvin region. (Auth.)

Very-high-energy nuclear physics

International Nuclear Information System (INIS)

Frankel, S.

1983-06-01

In 1980 we carried out an extensive series of experiments on alpha-alpha collisions in the ISR. The purpose of the experiment was to discover something new for example, to search for some evidence of new correlated behaviour, and, in particular, to search for the existence of the formation of a quark-gluon plasma. The reason for this hope lay in the fact that the ISR experiments were to be carried out at ultrarelativistic energies of 1000 GeV/c in the alpha cm. This is a region where it is known that the mean pion multiplicities are very large and it is possible to sample events with event multiplicities of at least 200. Another important feature was the fact that remarkable spectrometers existed at the ISR to make definitive studies of the whole event structure. The apparatus of the AFS had the capability of detecting 50 charged particles in an apparatus covering 85% of the total solid angle. The momentum of each particle could be measured with high accuracy and protons, kaons, pions and their antiparticles could be identified, along with neutral lambdas and kaons. The ability to handle large multiplicities was important in the study of violent collisions. To describe the results of these experiments we shall list below the titles of papers published, in press, or in preparation which will have been completed by the end of this fiscal year, commenting on the results and their significance

Redefining interrelationship between nuclear safety, nuclear security and safeguards

International Nuclear Information System (INIS)

Irie, Kazutomo

2012-01-01

Since the beginning of this century, the so-called 3Ss (Nuclear Safety, Nuclear Security and Safeguards) have become major regulatory areas for peaceful uses of nuclear energy. In order to rationalize the allocation of regulatory resources, interrelationship of the 3Ss should be investigated. From the viewpoint of the number of the parties concerned in regulation, nuclear security is peculiar with having “aggressors” as the third party. From the viewpoint of final goal of regulation, nuclear security in general and safeguards share the goal of preventing non-peaceful uses of nuclear energy, though the goal of anti-sabotage within nuclear security is rather similar to nuclear safety. As often recognized, safeguards are representative of various policy tools for nuclear non-proliferation. Strictly speaking, it is not safeguards as a policy tool but nuclear non-proliferation as a policy purpose that should be parallel to other policy purposes (nuclear safety and nuclear security). That suggests “SSN” which stands for Safety, Security and Non-proliferation is a better abbreviation rather than 3Ss. Safeguards as a policy tool should be enumerated along with nuclear safety regulation, nuclear security measures and trade controls on nuclear-related items. Trade controls have been playing an important role for nuclear non-proliferation. These policy tools can be called “SSST” in which Trade controls are also emphasized along with Safety regulation, Security measures and Safeguards. (author)

Nuclear power and nuclear safety 2006

International Nuclear Information System (INIS)

Lauritzen, B.; Oelgaard, P.L.; Kampmann, D.; Majborn, B.; Nonboel, E.; Nystrup, P.E.

2007-04-01

The report is the fourth report in a series of annual reports on the international development of nuclear power production, with special emphasis on safety issues and nuclear emergency preparedness. The report is written in collaboration between Risoe National Laboratory and the Danish Emergency Management Agency. The report for 2006 covers the following topics: status of nuclear power production, regional trends, reactor development and development of emergency management systems, safety related events of nuclear power, and international relations and conflicts. (LN)

Nuclear power and nuclear safety 2004

International Nuclear Information System (INIS)

2005-03-01

The report is the second report in a new series of annual reports on the international development of nuclear power production, with special emphasis on safety issues and nuclear emergency preparedness. The report is written in collaboration between Risoe National Laboratory and the Danish Emergency Management Agency. The report for 2004 covers the following topics: status of nuclear power production, regional trends, reactor development and development of emergency management systems, safety related events of nuclear power and international relations and conflicts. (ln)

Nuclear power and nuclear safety 2005

International Nuclear Information System (INIS)

Lauritzen, B.; Oelgaard, P.L.; Kampman, D.; Majborn, B.; Nonboel, E.; Nystrup, P.E.

2006-03-01

The report is the third report in a series of annual reports on the international development of nuclear power production, with special emphasis on safety issues and nuclear emergency preparedness. The report is written in collaboration between Risoe National Laboratory and the Danish Emergency Management Agency. The report for 2005 covers the following topics: status of nuclear power production, regional trends, reactor development and development of emergency management systems, safety related events of nuclear power and international relations and conflicts. (ln)

Position paper on nuclear proliferation issues preventing nuclear proliferation. A duty for the nuclear community

Energy Technology Data Exchange (ETDEWEB)

Goldschmidt, Pierre; Bonin, Bernard [ENS High Scientific Council, Brussels (Belgium)

2010-06-15

The production of electricity from nuclear power plants is widely seen today as having an increasing role to play in meeting global energy requirements in a sustainable manner. Conscious of the inherently sensitive nature of nuclear technology and materials the ENS-HSC (European Nuclear Society - High Scientific Council) is well aware that a severe safety, security, environmental or proliferation mishap stemming from nuclear energy anywhere in the world would undermine the potential for nuclear energy to contribute to the global energy supply and the minimization of harmful carbon emissions. While the safety of nuclear power plants has continuously improved over the last three decades, the same degree of success cannot be claimed when it comes to the achievements of the international community in stemming the risk of nuclear weapons proliferation. This unfortunate situation is due to both technical and political reasons. The European nuclear industry is committed to the exclusively peaceful use of nuclear energy and to export nuclear facilities and related materials, equipment and technology solely in accordance with relevant national export laws and regulations, Nuclear Suppliers Group guidelines and pertinent United Nations Security Council Resolutions. The ENS-HSC considers that, as a manifestation of their strong commitment to nonproliferation, it is important for the nuclear industry to pay special attention to and promote proliferation-resistant designs and to take IAEA safeguards requirements into account at the design stage. Preventing nuclear proliferation is primarily the responsibility of states but, as major stakeholders, the nuclear industry and scientific community should actively support nuclear disarmament as foreseen in the Non-Proliferation Treaty and measures necessary to strengthen the non-proliferation regime, particularly the international control of the flux of nuclear material and technology. (orig.)

Position paper on nuclear proliferation issues preventing nuclear proliferation. A duty for the nuclear community

International Nuclear Information System (INIS)

Goldschmidt, Pierre; Bonin, Bernard

2010-01-01

The production of electricity from nuclear power plants is widely seen today as having an increasing role to play in meeting global energy requirements in a sustainable manner. Conscious of the inherently sensitive nature of nuclear technology and materials the ENS-HSC (European Nuclear Society - High Scientific Council) is well aware that a severe safety, security, environmental or proliferation mishap stemming from nuclear energy anywhere in the world would undermine the potential for nuclear energy to contribute to the global energy supply and the minimization of harmful carbon emissions. While the safety of nuclear power plants has continuously improved over the last three decades, the same degree of success cannot be claimed when it comes to the achievements of the international community in stemming the risk of nuclear weapons proliferation. This unfortunate situation is due to both technical and political reasons. The European nuclear industry is committed to the exclusively peaceful use of nuclear energy and to export nuclear facilities and related materials, equipment and technology solely in accordance with relevant national export laws and regulations, Nuclear Suppliers Group guidelines and pertinent United Nations Security Council Resolutions. The ENS-HSC considers that, as a manifestation of their strong commitment to nonproliferation, it is important for the nuclear industry to pay special attention to and promote proliferation-resistant designs and to take IAEA safeguards requirements into account at the design stage. Preventing nuclear proliferation is primarily the responsibility of states but, as major stakeholders, the nuclear industry and scientific community should actively support nuclear disarmament as foreseen in the Non-Proliferation Treaty and measures necessary to strengthen the non-proliferation regime, particularly the international control of the flux of nuclear material and technology. (orig.)

Nuclear moments

CERN Document Server

Kopferman, H; Massey, H S W

1958-01-01

Nuclear Moments focuses on the processes, methodologies, reactions, and transformations of molecules and atoms, including magnetic resonance and nuclear moments. The book first offers information on nuclear moments in free atoms and molecules, including theoretical foundations of hyperfine structure, isotope shift, spectra of diatomic molecules, and vector model of molecules. The manuscript then takes a look at nuclear moments in liquids and crystals. Discussions focus on nuclear paramagnetic and magnetic resonance and nuclear quadrupole resonance. The text discusses nuclear moments and nucl

The applications of nuclear techniques in nuclear medicine

International Nuclear Information System (INIS)

Zhao Huiyang

1986-01-01

There are a great deal of advanced techniques in nuclear medicine imaging, because many recent achivements of nuclear techniques have been applied to medicine in recent years. This paper presents the effects of nuclear techniques in development of nuclear medicine imaging. The first part describes radiopharmaceuticals and nuclear medicine imaging including commonly used 99m Tc labeled agents and cyclotron produced radionuclides for organ imaging. The second part describes nuclear medicine instrucments, including PECT, SPECT, MRI ect.; and discussions on the advantages, disadvantages and present status

Nuclear energy and nuclear technology in Switzerland

International Nuclear Information System (INIS)

Graf, P.

1975-01-01

The energy crisis, high fuel costs and slow progress in the development of alternative energy sources, e.g. solar energy have given further impetus to nuclear power generation. The Swiss nuclear energy programme is discussed and details are given of nuclear station in operation, under construction, in the project stage and of Swiss participation in foreign nuclear stations. Reference is made to the difficulties, delays and resulting cost increases caused by local and regional opposition to nuclear power stations. The significant contributions made by Swiss industry and Swiss consulting engineers are discussed. (P.G.R.)

Nuclear power and the nuclear fuel cycle

International Nuclear Information System (INIS)

Scurr, I.F.; Silver, J.M.

1990-01-01

Australian Nuclear Science and Technology Organization maintains an ongoing assessment of the world's nuclear technology developments, as a core activity of its Strategic Plan. This publication reviews the current status of the nuclear power and the nuclear fuel cycle in Australia and around the world. Main issues discussed include: performances and economics of various types of nuclear reactors, uranium resources and requirements, fuel fabrication and technology, radioactive waste management. A brief account of the large international effort to demonstrate the feasibility of fusion power is also given. 11 tabs., ills

Nuclear winter or nuclear fall?

Science.gov (United States)

Berger, André

Climate is universal. If a major modern nuclear war (i.e., with a large number of small-yield weapons) were to happen, it is not even necessary to have a specific part of the world directly involved for there to be cause to worry about the consequences for its inhabitants and their future. Indeed, smoke from fires ignited by the nuclear explosions would be transported by winds all over the world, causing dark and cold. According to the first study, by Turco et al. [1983], air surface temperature over continental areas of the northern mid-latitudes (assumed to be the nuclear war theatre) would fall to winter levels even in summer (hence the term “nuclear winter”) and induce drastic climatic conditions for several months at least. The devastating effects of a nuclear war would thus last much longer than was assumed initially. Discussing to what extent these estimations of long-term impacts on climate are reliable is the purpose of this article.

Asia nuclear-test-ban network for nuclear non-proliferation

International Nuclear Information System (INIS)

Shinohara, Nobuo; Kokaji, Lisa; Ichimasa, Sukeyuki

2010-01-01

In Global Center of Excellence Program of The University of Tokyo, Non- Proliferation Study Committee by the members of nuclear industries, electricity utilities, nuclear energy institutes and universities has initiated on October 2008 from the viewpoints of investigating a package of measures for nuclear non-proliferation and bringing up young people who will support the near-future nuclear energy system. One of the non-proliferation issues in the Committee is the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Objective of this treaty is to cease all nuclear weapon test explosions and all other nuclear explosion. This purpose should be contributed effectively to the political stability of the Asian region by continuous efforts to eliminate the nuclear weapons. In the Committee, by extracting several issues related to the CTBT, conception of 'Asia nuclear-test-ban network for nuclear non-proliferation' has been discussed with the aim of the nuclear-weapon security in Asian region, where environmental nuclear-test monitoring data is mainly treated and utilized. In this paper, the conception of the 'network' is presented in detail. (author)

Strategy of nuclear power in Korea, non-nuclear-weapon state and peaceful use of nuclear power

International Nuclear Information System (INIS)

Nagasaki, Takao

2005-01-01

The nuclear power plant started at Kori in Korea in April, 1978. Korea has carried out development of nuclear power as a national policy. The present capacity of nuclear power plants takes the sixes place in the world. It supplies 42% total power generation. The present state of nuclear power plant, nuclear fuel cycle facility, strategy of domestic production of nuclear power generation, development of next generation reactor and SMART, strategy of export in corporation with industry, government and research organization, export of nuclear power generation in Japan, nuclear power improvement project with Japan, Korea and Asia, development of nuclear power system with nuclear diffusion resistance, Hybrid Power Extraction Reactor System, radioactive waste management and construction of joint management and treatment system of spent fuel in Asia are stated. (S.Y.)

Nuclear power

International Nuclear Information System (INIS)

Abd Khalik Wood

2005-01-01

This chapter discussed the following topics related to the nuclear power: nuclear reactions, nuclear reactors and its components - reactor fuel, fuel assembly, moderator, control system, coolants. The topics titled nuclear fuel cycle following subtopics are covered: , mining and milling, tailings, enrichment, fuel fabrication, reactor operations, radioactive waste and fuel reprocessing. Special topic on types of nuclear reactor highlighted the reactors for research, training, production, material testing and quite detail on reactors for electricity generation. Other related topics are also discussed: sustainability of nuclear power, renewable nuclear fuel, human capital, environmental friendly, emission free, impacts on global warming and air pollution, conservation and preservation, and future prospect of nuclear power

Nuclear power and the nuclear fuel cycle

International Nuclear Information System (INIS)

Hardy, C.J.; Silver, J.M.

1985-09-01

The report provides data and assessments of the status and prospects of nuclear power and the nuclear fuel cycle. The report discusses the economic competitiveness of nuclear electricity generation, the extent of world uranium resources, production and requirements, uranium conversion and enrichment, fuel fabrication, spent fuel treatment and radioactive waste management. A review is given of the status of nuclear fusion research

Building world-wide nuclear industry success stories - Safe management of nuclear waste and used nuclear fuel

International Nuclear Information System (INIS)

Saint-Pierre, S.

2005-01-01

Full text: This WNA Position Statement summarizes the worldwide nuclear industry's record, progress and plans in safely managing nuclear waste and used nuclear fuel. The global industry's safe waste management practices cover the entire nuclear fuel-cycle, from the mining of uranium to the long-term disposal of end products from nuclear power reactors. The Statement's aim is to provide, in clear and accurate terms, the nuclear industry's 'story' on a crucially important subject often clouded by misinformation. Inevitably, each country and each company employs a management strategy appropriate to a specific national and technical context. This Position Statement reflects a confident industry consensus that a common dedication to sound practices throughout the nuclear industry worldwide is continuing to enhance an already robust global record of safe management of nuclear waste and used nuclear fuel. This text focuses solely on modern civil programmes of nuclear-electricity generation. It does not deal with the substantial quantities of waste from military or early civil nuclear programmes. These wastes fall into the category of 'legacy activities' and are generally accepted as a responsibility of national governments. The clean-up of wastes resulting from 'legacy activities' should not be confused with the limited volume of end products that are routinely produced and safely managed by today's nuclear energy industry. On the significant subject of 'Decommissioning of Nuclear Facilities', which is integral to modern civil nuclear power programmes, the WNA will offer a separate Position Statement covering the industry's safe management of nuclear waste in this context. The safe management of nuclear waste and used nuclear fuel is a widespread, well-demonstrated reality. This strong safety record reflects a high degree of nuclear industry expertise and of industry responsibility toward the well-being of current and future generations. Accumulating experience and

Development of nuclear energy and nuclear policy in China

International Nuclear Information System (INIS)

You Deliang

1993-11-01

Status of nuclear power development in China, nuclear policy and nuclear power programme are described. Issues regarding nuclear fuel cycle system, radioactive waste management and international cooperation in the field of peaceful use of nuclear energy are discussed

The Nuclear Review: the Institution of Nuclear Engineers' response to the Review of Nuclear Power

International Nuclear Information System (INIS)

Anon.

1994-01-01

The United Kingdom Government's Nuclear Review currently underway, addresses whether and in what form nuclear power should continue to be part of the country's power generation capability. This article sets out the response of the Institution of Nuclear Engineers to the Nuclear Review. This pro-nuclear group emphasises the benefits to be gained from diversity of generation in the energy supply industry. The environmentally benign nature of nuclear power is emphasised, in terms of gaseous emissions. The industry's excellent safety record also argues in favour of nuclear power. Finally, as power demand increases globally, a health U.K. nuclear industry could generate British wealth through power exports and via the construction industry. The Institution's view on radioactive waste management is also set out. (UK)

Theoretical studies in nuclear reactions and nuclear structure

International Nuclear Information System (INIS)

1992-05-01

Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. Hadrons in nuclear matter; the structure of hadrons; relativistic nuclear physics and heavy ion dynamics and related processes. The section on hadrons in nuclear matter groups together research items which are aimed at exploring ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. A very interesting result has been the finding that QCD sum rules supply a new insight into the decrease of the nucleon's mass in the nuclear medium. The quark condensate, which characterizes spontaneous chiral symmetry breaking of the late QCD vacuum, decreases in nuclear matter and this is responsible for the decrease of the nucleon's mass. The section on the structure of hadrons contains progress reports on our research aimed at understanding the structure of the nucleon. Widely different approaches are being studied, e.g., lattice gauge calculations, QCD sum rules, quark-meson models with confinement and other hedgehog models. A major goal of this type of research is to develop appropriate links between nuclear physics and QCD. The section on relativistic nuclear physics represents our continuing interest in developing an appropriate relativistic framework for nuclear dynamics. A Lorentz-invariant description of the nuclear force suggests a similar decrease of the nucleon's mass in the nuclear medium as has been found from QCD sum rules. Work in progress extends previous successes in elastic scattering to inelastic scattering of protons by nuclei. The section on heavy ion dynamics and related processes reports on research into the e + e - problem and heavy ion dynamics

Nuclear data services of the Nuclear Data Centers Network available at the National Nuclear Data Center

International Nuclear Information System (INIS)

McLane, V.

1997-01-01

The Nuclear Data Centers Network provides low and medium energy nuclear reaction data to users around the world. Online retrievals are available through the U.S. National Nuclear Data Center, the Nuclear Energy Agency Data Bank, and the IAEA Nuclear Data Section from these extensive bibliographic, experimental data, and evaluated data files. In addition to nuclear reaction data, the various databases also provide nuclear structure and decay data, and other information of interest to users. The WorldWideWeb sites at the National Nuclear Data Center and the NEA Data Bank provide access to some of the Centers' files. (orig.)

Control of Nuclear Materials and Special Equipment (Nuclear Safety Regulations)

International Nuclear Information System (INIS)

Cizmek, A.; Prah, M.; Medakovic, S.; Ilijas, B.

2008-01-01

Based on Nuclear Safety Act (OG 173/03) the State Office for Nuclear Safety (SONS) in 2008 adopted beside Ordinance on performing nuclear activities (OG 74/06) and Ordinance on special conditions for individual activities to be performed by expert organizations which perform activities in the area of nuclear safety (OG 74/06) the new Ordinance on the control of nuclear material and special equipment (OG 15/08). Ordinance on the control of nuclear material and special equipment lays down the list of nuclear materials and special equipment as well as of nuclear activities covered by the system of control of production of special equipment and non-nuclear material, the procedure for notifying the intention to and filing the application for a license to carry out nuclear activities, and the format and contents of the forms for doing so. This Ordinance also lays down the manner in which nuclear material records have to be kept, the procedure for notifying the State administration organization (regulatory body) responsible for nuclear safety by the nuclear material user, and the keeping of registers of nuclear activities, nuclear material and special equipment by the State administration organization (regulatory body) responsible for nuclear safety, as well as the form and content of official nuclear safety inspector identification card and badge.(author)

Leading twist nuclear shadowing, nuclear generalized parton distributions and nuclear DVCS at small x

Energy Technology Data Exchange (ETDEWEB)

Guzey, Vadim; Goeke, Klaus; Siddikov, Marat

2009-01-01

We generalize the leading twist theory of nuclear shadowing and calculate quark and gluon generalized parton distributions (GPDs) of spinless nuclei. We predict very large nuclear shadowing for nuclear GPDs. In the limit of the purely transverse momentum transfer, our nuclear GPDs become impact parameter dependent nuclear parton distributions (PDFs). Nuclear shadowing induces non-trivial correlations between the impact parameter $b$ and the light-cone fraction $x$. We make predictions for the deeply virtual Compton scattering (DVCS) amplitude and the DVCS cross section on $^{208}$Pb at high energies. We calculate the cross section of the Bethe-Heitler (BH) process and address the issue of the extraction of the DVCS signal from the $e A \\to e \\gamma A$ cross section. We find that the $e A \\to e \\gamma A$ differential cross section is dominated by DVCS at the momentum transfer $t$ near the minima of the nuclear form factor. We also find that nuclear shadowing leads

Nuclear forensics

International Nuclear Information System (INIS)

Venugopal, V.

2010-01-01

Nuclear forensics is the analysis of nuclear materials recovered from either the capture of unused materials, or from the radioactive debris following a nuclear explosion and can contribute significantly to the identification of the sources of the materials and the industrial processes used to obtain them. In the case of an explosion, nuclear forensics can also reconstruct key features of the nuclear device. Nuclear forensic analysis works best in conjunction with other law enforcement, radiological protection dosimetry, traditional forensics, and intelligence work to provide the basis for attributing the materials and/or nuclear device to its originators. Nuclear forensics is a piece of the overall attribution process, not a stand-alone activity

The role of nuclear law in nuclear safety after Fukushima

International Nuclear Information System (INIS)

Cardozo, Diva E. Puig

2013-01-01

The paper contains the following topics: nuclear law, origin and evolution, role of the legal instruments on nuclear safety, nuclear safety the impact of major nuclear accidents: Chernobyl and Fukushima. The response of the nuclear law post Fukushima. Safety and security. International framework for nuclear safety: nuclear convention joint convention on safety on spent fuel management and on the safety of radioactive waste management. The Fukushima World Conference on Nuclear Safety. Convention on Prompt Notification and Assistance in case of a Nuclear Accident or Radiological Emergency. Plan of Action for Nuclear Safety. IAEA recommendations for the safety transport of radioactive material. International framework for nuclear security. Convention on the Physical Protection of Nuclear Materials. International Convention for the Suppression of Acts Against Nuclear Terrorism. Resolution No. 1540 of the Security Council of United Nations (2004). Measures to strengthen international safety. Code of conduct on the safety research reactor

Nuclear power. Volume 1. Nuclear power plant design

International Nuclear Information System (INIS)

Pedersen, E.S.

1978-01-01

NUCLEAR POWER PLANT DESIGN is intended to be used as a working reference book for management, engineers and designers, and as a graduate-level text for engineering students. The book is designed to combine theory with practical nuclear power engineering and design experience, and to give the reader an up-to-date view of the status of nuclear power and a basic understanding of how nuclear power plants function. Volume 1 contains the following chapters; (1) nuclear reactor theory; (2) nuclear reactor design; (3) types of nuclear power plants; (4) licensing requirements; (5) shielding and personnel exposure; (6) containment and structural design; (7) main steam and turbine cycles; (8) plant electrical system; (9) plant instrumentation and control systems; (10) radioactive waste disposal (waste management) and (11) conclusion

Emerging nuclear energy systems and nuclear weapon proliferation

International Nuclear Information System (INIS)

Gsponer, A.; Sahin, S.; Jasani, B.

1983-01-01

Generally when considering problems of proliferation of nuclear weapons, discussions are focused on horizontal proliferation. However, the emerging nuclear energy systems currently have an impact mainly on vertical proliferation. The paper indicates that technologies connected with emerging nuclear energy systems, such as fusion reactors and accelerators, enhance the knowledge of thermonuclear weapon physics and will enable production of military useful nuclear materials (including some rare elements). At present such technologies are enhancing the arsenal of the nuclear weapon states. But one should not forget the future implications for horizontal proliferation of nuclear weapons as some of the techniques will in the near future be within the technological and economic capabilities of non-nuclear weapon states. Some of these systems are not under any international control. (orig.) [de

Securing Chinese nuclear power development: further strengthening nuclear security

International Nuclear Information System (INIS)

Zhang Hui

2014-01-01

Chinese President Xi Jinping addresses China's new concept of nuclear security with four 'equal emphasis' at the third Nuclear Security Summit, and makes four commitments to strengthen nuclear security in the future. To convert President Xi's political commitments into practical, sustainable reality, China should take further steps to install a complete, reliable, and effective security system to ensure that all its nuclear materials and nuclear facilities are effectively protected against the full spectrum of plausible terrorist and criminal threats. This paper suggests the following measures be taken to improve China's existing nuclear security system, including updating and clarifying the requirements for a national level DBT; updating and enforcing existing regulations; further promoting nuclear security culture; balancing the costs of nuclear security, and further strengthening international cooperation on nuclear security. (author)

Model Action Plan for Nuclear Forensics and Nuclear Attribution

International Nuclear Information System (INIS)

Dudder, G B; Niemeyer, S; Smith, D K; Kristo, M J

2004-01-01

Nuclear forensics and nuclear attribution have become increasingly important tools in the fight against illegal trafficking in nuclear and radiological materials. This technical report documents the field of nuclear forensics and nuclear attribution in a comprehensive manner, summarizing tools and procedures that have heretofore been described independently in the scientific literature. This report also provides national policy-makers, decision-makers, and technical managers with guidance for responding to incidents involving the interdiction of nuclear and radiological materials. However, due to the significant capital costs of the equipment and the specialized expertise of the personnel, work in the field of nuclear forensics has been restricted so far to a handful of national and international laboratories. In fact, there are a limited number of specialists who have experience working with interdicted nuclear materials and affiliated evidence. Most of the laboratories that have the requisite equipment, personnel, and experience to perform nuclear forensic analysis are participants in the Nuclear Smuggling International Technical Working Group or ITWG (see Section 1.8). Consequently, there is a need to disseminate information on an appropriate response to incidents of nuclear smuggling, including a comprehensive approach to gathering evidence that meets appropriate legal standards and to developing insights into the source and routes of nuclear and radiological contraband. Appendix A presents a ''Menu of Options'' for other Member States to request assistance from the ITWG Nuclear Forensics Laboratories (INFL) on nuclear forensic cases

Theoretical studies in nuclear reactions and nuclear structure

Energy Technology Data Exchange (ETDEWEB)

1992-05-01

Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. Hadrons in nuclear matter; the structure of hadrons; relativistic nuclear physics and heavy ion dynamics and related processes. The section on hadrons in nuclear matter groups together research items which are aimed at exploring ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. A very interesting result has been the finding that QCD sum rules supply a new insight into the decrease of the nucleon's mass in the nuclear medium. The quark condensate, which characterizes spontaneous chiral symmetry breaking of the late QCD vacuum, decreases in nuclear matter and this is responsible for the decrease of the nucleon's mass. The section on the structure of hadrons contains progress reports on our research aimed at understanding the structure of the nucleon. Widely different approaches are being studied, e.g., lattice gauge calculations, QCD sum rules, quark-meson models with confinement and other hedgehog models. A major goal of this type of research is to develop appropriate links between nuclear physics and QCD. The section on relativistic nuclear physics represents our continuing interest in developing an appropriate relativistic framework for nuclear dynamics. A Lorentz-invariant description of the nuclear force suggests a similar decrease of the nucleon's mass in the nuclear medium as has been found from QCD sum rules. Work in progress extends previous successes in elastic scattering to inelastic scattering of protons by nuclei. The section on heavy ion dynamics and related processes reports on research into the e{sup +}e{sup {minus}} problem and heavy ion dynamics.

Report of Activity, 1996 - 1997. Vol. 1. Experimental Research Division

International Nuclear Information System (INIS)

Brunelle, Alain; Morlet, Marcel; Hutin, Christiane

1999-01-01

This report presents the activity of Experimental Research Division of the Orsay Institute of Nuclear Physics on 1996 - 1997. The following 10 sections are represented through summary reports or short communications: 1. Nuclear structure far from stability (with the topics: 1.1. Exotic nuclei -Secondary beams of radioactive ions; 1.2. On-line spectroscopy; 1.3. Discrete high-spin states); 2. High excitation energy nuclear states; 3. Nuclear matter and nucleus-nucleus collisions (which includes 3.1. Evolution of reaction mechanisms from 10 to 150 MeV/u; 3.2. Hot nuclei; 3.3. Ultra-relativistic collisions); 4. Hadronic physics (with the topics: 4.1 Meson production; 4.2. Spin modes in nuclei; 4.3. Hadronic physics with electromagnetic probes); 5. Radiochemistry (with the sub-divisions: 5.1. Studies related to radioactive waste management; 5.2. Optical spectroscopy of actinide and lanthanide ions in solid media); 6. Inter-disciplinary research (with the topics: 6.1. Heavy ion and cluster interactions with matter and surfaces; 6.2. Medical imaging); 8. Teaching; 9. Publications - Conferences - Seminars; 10 Internal reports - Lectures - Theses - Patents. The scientific staff of the following groups is also presented: 1. Group of Nuclear Structure by Reactions; 2. Group of Heavy Ion Nuclear Physics; 3. Intermediary Energy Group; 4. Hadron Physics Group; 5. Nuclei-Ions-Matter Group; 6. Radiochemistry Group; 7. Group of Exotic Deformed Nuclei; 8. Group of Physics-Biology Interface

Report of Activity, 1996 - 1997. Vol. 1. Experimental Research Division; Rapport d`activite 1996 - 1997. Tome 1. Division de Recherche Experimentale

Energy Technology Data Exchange (ETDEWEB)

Brunelle, Alain; Morlet, Marcel; Hutin, Christiane [eds.; Inst. de Physique Nucleaire, Paris-11 Univ., 91 - Orsay (France)

1999-11-01

This report presents the activity of Experimental Research Division of the Orsay Institute of Nuclear Physics on 1996 - 1997. The following 10 sections are represented through summary reports or short communications: 1. Nuclear structure far from stability (with the topics: 1.1. Exotic nuclei -Secondary beams of radioactive ions; 1.2. On-line spectroscopy; 1.3. Discrete high-spin states); 2. High excitation energy nuclear states; 3. Nuclear matter and nucleus-nucleus collisions (which includes 3.1. Evolution of reaction mechanisms from 10 to 150 MeV/u; 3.2. Hot nuclei; 3.3. Ultra-relativistic collisions); 4. Hadronic physics (with the topics: 4.1 Meson production; 4.2. Spin modes in nuclei; 4.3. Hadronic physics with electromagnetic probes); 5. Radiochemistry (with the sub-divisions: 5.1. Studies related to radioactive waste management; 5.2. Optical spectroscopy of actinide and lanthanide ions in solid media); 6. Inter-disciplinary research (with the topics: 6.1. Heavy ion and cluster interactions with matter and surfaces; 6.2. Medical imaging); 8. Teaching; 9. Publications - Conferences - Seminars; 10 Internal reports - Lectures - Theses - Patents. The scientific staff of the following groups is also presented: 1. Group of Nuclear Structure by Reactions; 2. Group of Heavy Ion Nuclear Physics; 3. Intermediary Energy Group; 4. Hadron Physics Group; 5. Nuclei-Ions-Matter Group; 6. Radiochemistry Group; 7. Group of Exotic Deformed Nuclei; 8. Group of Physics-Biology Interface

The Romanian nuclear regulatory body as a nuclear communicator

International Nuclear Information System (INIS)

Cluculescu, Cristina

2000-01-01

A comprehensive nuclear law environment could be a relevant tool to promote greater confidence in the nuclear energy. Romania has had laws in place governing the regulation of nuclear activities since 1974, which remained in force throughout and subsequent to the national constitutional changes. Up to December 1996, the CNCAN activities were based on Law No. 61/1974 for the development of the nuclear activities in Romania and Law No. 61982 on the quality assurance of the nuclear facilities and nuclear power plants. The Nuclear Safety legislation has been enacted in November 1974 (Law No. 61/1974) and it followed as closely as possible (for that time) the US Atomic Energy Act of 1954, as amended subsequently. The Romanian nuclear regulatory body, called National Commission for Nuclear Activities Control (CNCAN) is a governmental organization responsible for the development of the regulatory framework, the control of its implementation and for the licensing of nuclear facilities. An important issue of CNCAN is to provide the correct and reasoning information to the public. The most important topics focused on nuclear activities for the interest of mass media in Romania are: Radioactive waste management; The cost and benefit of nuclear energy compared by conventional energy; The conditions for transportation of radioactive materials; The consequences of a suppositional nuclear accidents; The safety in operation for nuclear installations. The information provided to press and public by regulatory body is clearly and well structured. The target is to clearly explain to mass media and the public should understand very well the difference between the meaning of a nuclear accident, nuclear incident or nuclear event. CNCAN monitories and surveys the operation in safe conditions the nuclear facilities and plants, the protection against nuclear radiation of the professionally exposed personnel, of the population, of the environment and the material goods. It is also

[Nuclear theory

International Nuclear Information System (INIS)

Haxton, W.

1990-01-01

This report discusses research in nuclear physics. Topics covered in this paper are: symmetry principles; nuclear astrophysics; nuclear structure; quark-gluon plasma; quantum chromodynamics; symmetry breaking; nuclear deformation; and cold fusion

Ultrarelativistic cascades and strangeness production

Energy Technology Data Exchange (ETDEWEB)

Kahana, D.E. [State Univ. of New York, Stony Brook, NY (United States). Dept. of Physics; Kahana, S.H. [Brookhaven National Lab., Upton, NY (United States). Physics Dept.

1998-08-24

A two-phase cascade code, LUCIFER II, developed for the treatment of ultra high energy-ion-ion collisions is applied to the production of strangeness at SPS energies {radical}(s)=17-20. This simulation is able to simultaneously describe both hard processes such as Drell-Yan and slower, soft processes such as the production of light mesons by separating the dynamics into two steps, a fast cascade involving only the nucleons in the original colliding relativistic ions followed, after an appropriate delay, by a normal multiscattering of the resulting excited baryons and mesons produced virtually in the first step. No energy loss can take place in the short time interval over which the first cascade takes place. The chief result is a reconciliation of the important Drell-Yan measurements with the apparent success of standard cascades to describe the nucleon stopping and meson production in heavy-ion experiments at the CERN SPS. (orig.) 26 refs.

Ultrarelativistic cascades and strangeness production

International Nuclear Information System (INIS)

Kahana, D.E.; Kahana, S.H.

1998-01-01

A two-phase cascade code, LUCIFER II, developed for the treatment of ultra high energy-ion-ion collisions is applied to the production of strangeness at SPS energies √(s)=17-20. This simulation is able to simultaneously describe both hard processes such as Drell-Yan and slower, soft processes such as the production of light mesons by separating the dynamics into two steps, a fast cascade involving only the nucleons in the original colliding relativistic ions followed, after an appropriate delay, by a normal multiscattering of the resulting excited baryons and mesons produced virtually in the first step. No energy loss can take place in the short time interval over which the first cascade takes place. The chief result is a reconciliation of the important Drell-Yan measurements with the apparent success of standard cascades to describe the nucleon stopping and meson production in heavy-ion experiments at the CERN SPS. (orig.)

Ultrarelativistic cascades and strangeness production

International Nuclear Information System (INIS)

Kahana, D.E.; Kahana, S.H.

1998-02-01

A two phase cascade, LUCIFER II, developed for the treatment of ultra high energy Ion-Ion collisions is applied to the production of strangeness at SPS energies. This simulation is able to simultaneously describe both hard processes such as Drell-Yan and slower, soft processes such as the production of light mesons by separating the dynamics into two steps, a fast cascade involving only the nucleons in the original colliding relativistic ions followed, after an appropriate delay, by a normal multiscattering of the resulting excited baryons and mesons produced virtually in the first step. No energy loss can take place in the short time interval over which the first cascade takes place. The chief result is a reconciliation of the important Drell-Yan measurements with the apparent success of standard cascades to describe the nucleon stopping and meson production in heavy ion experiments at the CERN SPS

Ultrarelativistic electromagnetic pulses in plasmas

Science.gov (United States)

Ashour-Abdalla, M.; Leboeuf, J. N.; Tajima, T.; Dawson, J. M.; Kennel, C. F.

1981-01-01

The physical processes of a linearly polarized electromagnetic pulse of highly relativistic amplitude in an underdense plasma accelerating particles to very high energies are studied through computer simulation. An electron-positron plasma is considered first. The maximum momenta achieved scale as the square of the wave amplitude. This acceleration stops when the bulk of the wave energy is converted to particle energy. The pulse leaves behind as a wake a vacuum region whose length scales as the amplitude of the wave. The results can be explained in terms of a snow plow or piston-like action of the radiation on the plasma. When a mass ratio other than unity is chosen and electrostatic effects begin to play a role, first the ion energy increases faster than the electron energy and then the electron energy catches up later, eventually reaching the same value.

China's nuclear safety regulatory body: The national nuclear safety administration

International Nuclear Information System (INIS)

Zhang Shiguan

1991-04-01

The establishment of an independent nuclear safety regulatory body is necessary for ensuring the safety of nuclear installations and nuclear fuel. Therefore the National Nuclear Safety Administration was established by the state. The aim, purpose, organization structure and main tasks of the Administration are presented. At the same time the practical examples, such as nuclear safety regulation on the Qinshan Nuclear Power Plant, safety review and inspections for the Daya Bay Nuclear Power Plant during the construction, and nuclear material accounting and management system in the nuclear fuel fabrication plant in China, are given in order to demonstrate the important roles having been played on nuclear safety by the Administration after its founding

Nuclear Deterrence in a New Nuclear Era

International Nuclear Information System (INIS)

Miraillet, Michel

2010-01-01

Within an unstable international environment and an unpredictable future, nuclear weapons will continue to play a major role in defense policies. Indeed, since disarmament currently seems an unlikely objective, nuclear weapons remain as a security guarantee. Within this context, talk of the global abolition of nuclear weapons remains essentially rhetorical and the supposed link between disarmament and non-proliferation is a tenuous one. The foremost purpose of both disarmament and nuclear deterrence must be security

Nuclear links

International Nuclear Information System (INIS)

1981-01-01

The subject is dealt with in sections: introduction; energy and the third world; world energy consumption 1978; oil -the energy dilemma; nuclear chains - introduction; uranium; Namibia; enrichment and reprocessing; countries with enrichment and reprocessing facilities; waste; conclusion; why take the nuclear option; third world countries with nuclear reactors; the arms connection; government spending and human resources 1977 (by countries); nuclear power - the final solution; the fascists; world bank; campaigns; community action in Plogoff; Australian labour movement; NUM against nuclear power; Scottish campaign; students against nuclear energy; anti-nuclear campaign; partizans; 3W1 disarmament and development; campaign ATOM; CANUC; 3W1; SANE. (U.K.)

Theoretical studies in nuclear reactions and nuclear structure

International Nuclear Information System (INIS)

Wallace, S.J.

1991-05-01

This report discusses topics in the following areas: Hadronic structure; hadrons in nuclei; hot hadronic matter; relativistic nuclear physics and NN interaction; leptonic emissions from high-Z heavy ion collisions; theoretical studies of heavy ion dynamics; nuclear pre-equilibrium reactions; classical chaotic dynamics and nuclear structure; and, theory of nuclear fission

Nuclear-fuel-cycle education: Module 1. Nuclear fuel cycle overview

International Nuclear Information System (INIS)

Eckhoff, N.D.

1981-07-01

This educational module is an overview of the nuclear-fule-cycle. The overview covers nuclear energy resources, the present and future US nuclear industry, the industry view of nuclear power, the International Nuclear Fuel Cycle Evaluation program, the Union of Concerned Scientists view of the nuclear-fuel-cycle, an analysis of this viewpoint, resource requirements for a model light water reactor, and world nuclear power considerations

Emergency Department Management of Trauma

DEFF Research Database (Denmark)

MacKenzie, Colin; Lippert, Freddy

1999-01-01

services (EMS) response times and advanced prehospital care increase the number of critically injured patients surviving sufficiently long to reach a hospital “in extremis.” Both scenarios provide challenges in the management of traumatized patients. This article addresses the management of severely......Initial assessment and management of severely injured patients may occur in a specialized area of an emergency department or in a specialized area of a trauma center. The time from injury until definitive management is of essence for survival of life-threatening trauma. The initial care delivered...... injured patients after these patients reach a hospital emergency department or a trauma center....

Nuclear Forensics' role in analyzing nuclear trafficking activities

International Nuclear Information System (INIS)

Hrnecek, E.; Mayer, K.; Schubert, A.; Wallenius, M.

2010-01-01

Nuclear forensics aims at identifying origin and intended use of nuclear material using information inherent to the nuclear material.The information gathered in nuclear forensics include isotopic composition, elemental composition, impurities and age of the material, macroscopic appearance and microstructure. The information so collected helps to solve criminal cases and put the individuals involved in nuclear trafficking in jails. The information also helps to improve safeguards and physical protection measures at place of theft or diversion to prevent future thefts or diversions.

Radionuclides for nuclear medicine: a nuclear physicists' view

DEFF Research Database (Denmark)

Cantone, M.; Haddad, F.; Harissopoulos, S.

2013-01-01

NuPECC (the Nuclear Physics European Collaboration Committee, an expert committee of the European Science Foundation) has the mission to strengthen European Collaboration in nuclear science through the promotion of nuclear physics and its trans-disciplinary use and application. NuPECC is currently...... working on a report on “Nuclear Physics for Medicine” and has set up a working group to review the present status and prospects of radionuclides for nuclear medicine. An interim report will be presented to seek comments and constructive input from EANM members. In particular it is investigated how nuclear...... physics Methods and nuclear physics facilities are supporting the development and supply of medical radionuclides and how this support could be further strengthened in future. Aspects that will be addressed: •In recent years, the reactor-based supply chain of 99Mo/99mTc generators was repeatedly...

Dare nuclear energy with the Australian Nuclear Association

International Nuclear Information System (INIS)

Anon.

2016-01-01

Australian authorities have been traditionally opposed to nuclear energy. The interdiction to build nuclear power plants in the Australian states without the approval of the federal authority was even officially written in the environment code in 1999. Today coal provides 75% of the electricity needs of Australia. Because of climate warming, things are changing, the Australian government is now considering the possibility of using nuclear energy and a site located in southern Australian has been selected for the disposal of low and intermediate level radioactive wastes. In this context the Australian Nuclear Association (ANA) is developing an ambitious program for the promotion of all the applications of nuclear energy through the organisation of conferences and meetings with various experts of nuclear industry. The aim is to make the public aware of the assets of nuclear energy. (A.C.)

Nuclear forensics

International Nuclear Information System (INIS)

Karadeniz, O.; Guenalp, G.

2010-01-01

This review discusses the methodology of nuclear forensics and illicit trafficking of nuclear materials. Nuclear forensics is relatively new scientific branch whose aim it is to read out material inherent from nuclear material. Nuclear forensics investigations have to be considered as part of a comprehensive set of measures for detection,interception, categorization and characterization of illicitly trafficking nuclear material. Prevention, detection and response are the main elements in combating illicit trafficking. Forensics is a key element in the response process. Forensic science is defined as the application of a broad spectrum of sciences to answer questions of interest to the legal system. Besides, in this study we will explain age determination of nuclear materials.

Nuclear power. Volume 2. Nuclear power project management

International Nuclear Information System (INIS)

Pedersen, E.S.

1978-01-01

NUCLEAR POWER PLANT DESIGN is intended to be used as a working reference book for management, engineers and designers, and as a graduate-level text for engineering students. The book is designed to combine theory with practical nuclear power engineering and design experience, and to give the reader an up-to-date view of the status of nuclear power and a basic understanding of how nuclear power plants function. Volume 2 contains the following chapters: (1) review of nuclear power plants; (2) licensing procedures; (3) safety analysis; (4) project professional services; (5) quality assurance and project organization; (6) construction, scheduling, and operation; (7) nuclear fuel handling and fuel management; (8) plant cost management; and (9) conclusion

Nuclear disarmament and the elimination of nuclear dangers

International Nuclear Information System (INIS)

Daerr, Hans-Joachim

2002-01-01

... today's threats to security and stability have become less predictable and require at the same time a joint response. They illustrate the need for a new international order organized around shared values, common norms of behaviour and the rule of law. Disarmament, arms control, and non-proliferation are indispensable elements of this cooperative international order... We have to make sure that the functions that are today attributed to nuclear weapons become dispensable ... Nuclear disarmament is the counterpart of the renunciation of nuclear weapons by non-nuclear-weapons states. This bargain must not be undermined ... The NPT is no licence to perpetuate the status of the nuclear 'haves' versus the nuclear 'have nots.' (author)

Nuclear material control systems for nuclear power plants

International Nuclear Information System (INIS)

1975-06-01

Paragraph 70.51(c) of 10 CFR Part 70 requires each licensee who is authorized to possess at any one time special nuclear material in a quantity exceeding one effective kilogram to establish, maintain, and follow written material control and accounting procedures that are sufficient to enable the licensee to account for the special nuclear material in his possession under license. While other paragraphs and sections of Part 70 provide specific requirements for nuclear material control systems for fuel cycle plants, such detailed requirements are not included for nuclear power reactors. This guide identifies elements acceptable to the NRC staff for a nuclear material control system for nuclear power reactors. (U.S.)

Nuclear knowledge, trust and public acceptance of nuclear developments

Energy Technology Data Exchange (ETDEWEB)

Berdahl, A.L.; Bell, B.S.; Bourassa, C.M.; Fried, D.J., E-mail: Loleen.Berdahl@usask.ca, E-mail: Bourassa@edwards.usask.ca, E-mail: Scott.Bell@usask.ca, E-mail: Jana.Fried@usask.ca [Univ. of Saskatchewan, Saskatoon, SK (Canada)

2014-07-01

While nuclear sector activities remain contentious public issues, studies suggest that knowledge levels and trust in nuclear actors can influence public attitudes. Drawing on original data from a 2013 representative telephone survey of Saskatchewan residents, this paper considers the extent to which knowledge and trust influence support for nuclear developments. Saskatchewan provides an interesting case study: while the province has a robust uranium mining industry, there are no nuclear power facilities, and the potential development of nuclear energy and nuclear fuel waste storage has been a source of spirited public debate. The study's results have implications for public education and policy initiatives regarding nuclear power developments. (author)

Nuclear knowledge, trust and public acceptance of nuclear developments

International Nuclear Information System (INIS)

Berdahl, A.L.; Bell, B.S.; Bourassa, C.M.; Fried, D.J.

2014-01-01

While nuclear sector activities remain contentious public issues, studies suggest that knowledge levels and trust in nuclear actors can influence public attitudes. Drawing on original data from a 2013 representative telephone survey of Saskatchewan residents, this paper considers the extent to which knowledge and trust influence support for nuclear developments. Saskatchewan provides an interesting case study: while the province has a robust uranium mining industry, there are no nuclear power facilities, and the potential development of nuclear energy and nuclear fuel waste storage has been a source of spirited public debate. The study's results have implications for public education and policy initiatives regarding nuclear power developments. (author)

Nuclear energy and the nuclear industry

International Nuclear Information System (INIS)

Chester, K.

1982-01-01

In order to make a real contribution to the nuclear energy debate (is nuclear energy the limitless solution to man's energy problems or the path to man's destruction) people must be aware of the facts. The Science Reference Library (SRL) has a collection of the primary sources of information on nuclear energy - especially journals. This guideline aims to draw attention to the up-to-date literature on nuclear energy and its technology, freely available for consultation in the main Holborn reading room. After explanations of where to look for particular types of information and the SRL classification, the booklet gives lists and brief notes on the sources held. These are abstracting and indexing periodicals and periodicals. Reports, conference proceedings, patents, bibliographies, directories, year-books and buyer's guides are covered very briefly but not listed. Nuclear reactor data and organisations are also listed with brief details of each. (U.K.)

Nuclear Liability and Insurance for nuclear Damage in Switzerland

International Nuclear Information System (INIS)

Reitsma, S. M. S.

1998-01-01

With nuclear power generating 43% of its total electricity production, Switzerland is amongst the states, employing the highest percentage of nuclear electricity. Although, the country has not ratified any of the international Nuclear Liability Conventions, its Nuclear Third Party Liability Act reflects all the principles, underlying those Conventions. The statutory liability of the operator of a Swiss nuclear installation itself being unlimited, the total insurance limit of CHF 770 m. provides the highest private insurance protection worldwide. With the support of its foreign Reinsurance Pools, the capacity for this insurance guarantee has, over more than 40 years, been built up by the Swiss Nuclear Insurance Pool. Apart from Third Party Liability cover, the Pool also provides Property insurance to Swiss nuclear installation operators and reinsurance cover to other nuclear insurers worldwide. (author)

Hot origin of the Little Bang

Energy Technology Data Exchange (ETDEWEB)

Akkelin, S.V. [Bogolyubov Institute for Theoretical Physics, Kiev (Ukraine); Universitaet Heidelberg, Institut fuer Theoretische Physik, Heidelberg (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung, ExtreMe Matter Institute EMMI, Darmstadt (Germany)

2017-12-15

Ultrarelativistic heavy ion collisions produce a quark-gluon matter which lies in the future light cone originating from given points on the t = z = 0 plane of the Minkowski spacetime manifold. We show that in a weak coupling regime the Minkowski vacuum of massless fields presents itself in the ''Little Bang'' region as a thermal state of low p{sub T} particles, in close analogy to the Unruh effect for uniformly accelerated observers which are causally restricted to a Rindler wedge. It can shed some light on the mechanisms of early time thermalization in ultrarelativistic heavy ion collisions. (orig.)

Two-electron photoionization cross sections at high energies

International Nuclear Information System (INIS)

Amusia, M.Ya.; Krivec, R.; Mandelzweig, V.B.

2003-01-01

Double and single electron photoionization cross sections and their ratios at high and ultra-relativistic energies are calculated for H - , He and helium-like ions in ground and excited states including triplet states. The ratios contain shake-off and quasi-free terms. A high precision non-variational wave function is used. The quasi-free mechanism increases the ratios impressively: for He we get 0.0762 instead of 0.0164 in the non-relativistic case. Ratios are inversely proportional to Z 2 , with a factor increasing from 0.094 in the nonrelativistic to 0.595 in the ultra-relativistic limit. (author)

The World Nuclear University: New partnership in nuclear education

International Nuclear Information System (INIS)

2007-07-01

The important role which the IAEA plays in assisting Member States in the preservation and enhancement of nuclear knowledge and in facilitating international collaboration in this area has been recognized by the General Conference of the International Atomic Energy Agency in resolutions GC(46)/RES/11B, GC(47)/RES/10B, GC(48)/RES/13 and GC(50)/RES/13. A continued focus of IAEA activities in managing nuclear knowledge is to support Member States to secure and sustain human resources for the nuclear sector, comprising both the replacement of retiring staff and building of new capacity. The IAEA assists Member States, particularly developing ones, in their efforts to sustain nuclear education and training in all areas of nuclear technology for peaceful purposes, which is a necessary prerequisite for succession planning, in particular through the networking of nuclear education and training, including activities of the World Nuclear University (WNU) and the Asian Network for Education in Nuclear Technology (ANENT). The report on the attached CD-ROM, The World Nuclear University: New Partnership in Nuclear Education, gives an overview of the history of the development of the World Nuclear University and related IAEA activities and contains an analysis and recommendations from the first WNU Summer Institute, held in 2005 in the USA

Emergency response and nuclear risk governance. Nuclear safety at nuclear power plant accidents

International Nuclear Information System (INIS)

Kuhlen, Johannes

2014-01-01

The present study entitled ''Emergency Response and Nuclear Risk Governance: nuclear safety at nuclear power plant accidents'' deals with issues of the protection of the population and the environment against hazardous radiation (the hazards of nuclear energy) and the harmful effects of radioactivity during nuclear power plant accidents. The aim of this study is to contribute to both the identification and remediation of shortcomings and deficits in the management of severe nuclear accidents like those that occurred at Chernobyl in 1986 and at Fukushima in 2011 as well as to the improvement and harmonization of plans and measures taken on an international level in nuclear emergency management. This thesis is divided into a theoretical part and an empirical part. The theoretical part focuses on embedding the subject in a specifically global governance concept, which includes, as far as Nuclear Risk Governance is concerned, the global governance of nuclear risks. Due to their characteristic features the following governance concepts can be assigned to these risks: Nuclear Safety Governance is related to safety, Nuclear Security Governance to security and NonProliferation Governance to safeguards. The subject of investigation of the present study is as a special case of the Nuclear Safety Governance, the Nuclear Emergency governance, which refers to off-site emergency response. The global impact of nuclear accidents and the concepts of security, safety culture and residual risk are contemplated in this context. The findings (accident sequences, their consequences and implications) from the analyses of two reactor accidents prior to Fukushima (Three Mile Iceland in 1979, Chernobyl in 1986) are examined from a historical analytical perspective and the state of the Nuclear Emergency governance and international cooperation aimed at improving nuclear safety after Chernobyl is portrayed by discussing, among other topics, examples of &apos

Nuclear physics

International Nuclear Information System (INIS)

Kamal, Anwar

2014-01-01

Explains the concepts in detail and in depth. Provides step-by-step derivations. Contains numerous tables and diagrams. Supports learning and teaching with numerous worked examples, questions and problems with answers. Sketches also the historical development of the subject. This textbook explains the experimental basics, effects and theory of nuclear physics. It supports learning and teaching with numerous worked examples, questions and problems with answers. Numerous tables and diagrams help to better understand the explanations. A better feeling to the subject of the book is given with sketches about the historical development of nuclear physics. The main topics of this book include the phenomena associated with passage of charged particles and radiation through matter which are related to nuclear resonance fluorescence and the Moessbauer effect., Gamov's theory of alpha decay, Fermi theory of beta decay, electron capture and gamma decay. The discussion of general properties of nuclei covers nuclear sizes and nuclear force, nuclear spin, magnetic dipole moment and electric quadrupole moment. Nuclear instability against various modes of decay and Yukawa theory are explained. Nuclear models such as Fermi Gas Model, Shell Model, Liquid Drop Model, Collective Model and Optical Model are outlined to explain various experimental facts related to nuclear structure. Heavy ion reactions, including nuclear fusion, are explained. Nuclear fission and fusion power production is treated elaborately.

Nuclear security - New challenge to the safety of nuclear power plants

International Nuclear Information System (INIS)

Li Ganjie

2008-01-01

The safety of nuclear power plants involves two aspects: one is to prevent nuclear accidents resulted from systems and equipments failure or human errors; the other is to refrain nuclear accidents from external intended attack. From this point of view, nuclear security is an organic part of the nuclear safety of power plants since they have basically the same goals and concrete measures with each other. In order to prevent malicious attacks; the concept of physical protection of nuclear facilities has been put forward. In many years, a series of codes and regulations as well as technical standard systems on physical protection had been developed at international level. The United Nations passed No. 1540 resolution as well as 'Convention on the Suppression of Acts of Nuclear terrorism', and revised 'Convention on Physical Protection of Nuclear Materials', which has enhanced a higher level capacity of preparedness by international community to deal with security issues of nuclear facilities. In China, in order to improve the capability of nuclear power plants on preventing and suppressing the external attacks, the Chinese government consecutively developed the related codes and standards as well as technical documents based on the existing laws and regulations, including 'Guide for the Nuclear Security of Nuclear Power Plants' and 'Guide for the Physical Protection of Nuclear Materials', so as to upgrade the legislative requirements for nuclear security in power plants. The government also made greater efforts to support the scientific research and staff training on physical protection, and satisfying the physical protection standards for newly-built nuclear facilities such as large scale nuclear power plants to meet requirement at international level. At the same time old facilities were renovated and the Chinese government established a nuclear emergency preparedness coordination mechanism, developed corresponding emergency preparedness plans, intensified the

South Africa's SAFARI From nuclear weapons to nuclear medicine ...

African Journals Online (AJOL)

... of nuclear energy for peaceful uses, such as power generation and nuclear ... Building on its nuclear expertise, South Africa has become one of the world's ... By converting its nuclear reactor, SAFARI-1, to produce and supply medical ...

Multistrange Baryon elliptic flow in Au+Au collisions at square root of sNN=200 GeV.

Science.gov (United States)

Adams, J; Aggarwal, M M; Ahammed, Z; Amonett, J; Anderson, B D; Arkhipkin, D; Averichev, G S; Badyal, S K; Bai, Y; Balewski, J; Barannikova, O; Barnby, L S; Baudot, J; Bekele, S; Belaga, V V; Bellingeri-Laurikainen, A; Bellwied, R; Berger, J; Bezverkhny, B I; Bharadwaj, S; Bhasin, A; Bhati, A K; Bhatia, V S; Bichsel, H; Bielcik, J; Bielcikova, J; Billmeier, A; Bland, L C; Blyth, C O; Blyth, S L; Bonner, B E; Botje, M; Boucham, A; Bouchet, J; Brandin, A V; Bravar, A; Bystersky, M; Cadman, R V; Cai, X Z; Caines, H; Calderón de la Barca Sánchez, M; Castillo, J; Catu, O; Cebra, D; Chajecki, Z; Chaloupka, P; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, Y; Cheng, J; Cherney, M; Chikanian, A; Christie, W; Coffin, J P; Cormier, T M; Cosentino, M R; Cramer, J G; Crawford, H J; Das, D; Das, S; Daugherity, M; de Moura, M M; Dedovich, T G; DePhillips, M; Derevschikov, A A; Didenko, L; Dietel, T; Dogra, S M; Dong, W J; Dong, X; Draper, J E; Du, F; Dubey, A K; Dunin, V B; Dunlop, J C; Dutta Mazumdar, M R; Eckardt, V; Edwards, W R; Efimov, L G; Emelianov, V; Engelage, J; Eppley, G; Erazmus, B; Estienne, M; Fachini, P; Faivre, J; Fatemi, R; Fedorisin, J; Filimonov, K; Filip, P; Finch, E; Fine, V; Fisyak, Y; Fornazier, K S F; Fu, J; Gagliardi, C A; Gaillard, L; Gans, J; Ganti, M S; Geurts, F; Ghazikhanian, V; Ghosh, P; Gonzalez, J E; Gos, H; Grachov, O; Grebenyuk, O; Grosnick, D; Guertin, S M; Guo, Y; Gupta, A; Gupta, N; Gutierrez, T D; Hallman, T J; Hamed, A; Hardtke, D; Harris, J W; Heinz, M; Henry, T W; Hepplemann, S; Hippolyte, B; Hirsch, A; Hjort, E; Hoffmann, G W; Horner, M J; Huang, H Z; Huang, S L; Hughes, E W; Humanic, T J; Igo, G; Ishihara, A; Jacobs, P; Jacobs, W W; Jedynak, M; Jiang, H; Jones, P G; Judd, E G; Kabana, S; Kang, K; Kaplan, M; Keane, D; Kechechyan, A; Khodyrev, V Yu; Kiryluk, J; Kisiel, A; Kislov, E M; Klay, J; Klein, S R; Koetke, D D; Kollegger, T; Kopytine, M; Kotchenda, L; Kowalik, K L; Kramer, M; Kravtsov, P; Kravtsov, V I; Krueger, K; Kuhn, C; Kulikov, A I; Kumar, A; Kutuev, R Kh; Kuznetsov, A A; Lamont, M A C; Landgraf, J M; Lange, S; Laue, F; Lauret, J; Lebedev, A; Lednicky, R; Lehocka, S; LeVine, M J; Li, C; Li, Q; Li, Y; Lin, G; Lindenbaum, S J; Lisa, M A; Liu, F; Liu, H; Liu, J; Liu, L; Liu, Q J; Liu, Z; Ljubicic, T; Llope, W J; Long, H; Longacre, R S; Lopez-Noriega, M; Love, W A; Lu, Y; Ludlam, T; Lynn, D; Ma, G L; Ma, J G; Ma, Y G; Magestro, D; Mahajan, S; Mahapatra, D P; Majka, R; Mangotra, L K; Manweiler, R; Margetis, S; Markert, C; Martin, L; Marx, J N; Matis, H S; Matulenko, Yu A; McClain, C J; McShane, T S; Meissner, F; Melnick, Yu; Meschanin, A; Miller, M L; Minaev, N G; Mironov, C; Mischke, A; Mishra, D K; Mitchell, J; Mohanty, B; Molnar, L; Moore, C F; Morozov, D A; Munhoz, M G; Nandi, B K; Nayak, S K; Nayak, T K; Nelson, J M; Netrakanti, P K; Nikitin, V A; Nogach, L V; Nurushev, S B; Odyniec, G; Ogawa, A; Okorokov, V; Oldenburg, M; Olson, D; Pal, S K; Panebratsev, Y; Panitkin, S Y; Pavlinov, A I; Pawlak, T; Peitzmann, T; Perevoztchikov, V; Perkins, C; Peryt, W; Petrov, V A; Phatak, S C; Picha, R; Planinic, M; Pluta, J; Porile, N; Porter, J; Poskanzer, A M; Potekhin, M; Potrebenikova, E; Potukuchi, B V K S; Prindle, D; Pruneau, C; Putschke, J; Rakness, G; Raniwala, R; Raniwala, S; Ravel, O; Ray, R L; Razin, S V; Reichhold, D; Reid, J G; Reinnarth, J; Renault, G; Retiere, F; Ridiger, A; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Rose, A; Roy, C; Ruan, L; Russcher, M; Sahoo, R; Sakrejda, I; Salur, S; Sandweiss, J; Sarsour, M; Savin, I; Sazhin, P S; Schambach, J; Scharenberg, R P; Schmitz, N; Schweda, K; Seger, J; Seyboth, P; Shahaliev, E; Shao, M; Shao, W; Sharma, M; Shen, W Q; Shestermanov, K E; Shimanskiy, S S; Sichtermann, E; Simon, F; Singaraju, R N; Smirnov, N; Snellings, R; Sood, G; Sorensen, P; Sowinski, J; Speltz, J; Spinka, H M; Srivastava, B; Stadnik, A; Stanislaus, T D S; Stock, R; Stolpovsky, A; Strikhanov, M; Stringfellow, B; Suaide, A A P; Sugarbaker, E; Suire, C; Sumbera, M; Surrow, B; Swanger, M; Symons, T J M; Szanto de Toledo, A; Tai, A; Takahashi, J; Tang, A H; Tarnowsky, T; Thein, D; Thomas, J H; Timmins, A R; Timoshenko, S; Tokarev, M; Trentalange, S; Tribble, R E; Tsai, O D; Ulery, J; Ullrich, T; Underwood, D G; Van Buren, G; van der Kolk, N; van Leeuwen, M; Vander Molen, A M; Varma, R; Vasilevski, I M; Vasiliev, A N; Vernet, R; Vigdor, S E; Viyogi, Y P; Vokal, S; Voloshin, S A; Waggoner, W T; Wang, F; Wang, G; Wang, G; Wang, X L; Wang, Y; Wang, Y; Wang, Z M; Ward, H; Watson, J W; Webb, J C; Westfall, G D; Wetzler, A; Whitten, C; Wieman, H; Wissink, S W; Witt, R; Wood, J; Wu, J; Xu, N; Xu, Z; Xu, Z Z; Yamamoto, E; Yepes, P; Yurevich, V I; Zborovsky, I; Zhang, H; Zhang, W M; Zhang, Y; Zhang, Z P; Zhong, C; Zoulkarneev, R; Zoulkarneeva, Y; Zubarev, A N; Zuo, J X

2005-09-16

We report on the first measurement of elliptic flow v2(pT) of multistrange baryons Xi- +Xi+ and Omega- + Omega+ in heavy-ion collisions. In minimum-bias Au+Au collisions at square root of s(NN)=200 GeV, a significant amount of elliptic flow, comparable to other nonstrange baryons, is observed for multistrange baryons which are expected to be particularly sensitive to the dynamics of the partonic stage of heavy-ion collisions. The pT dependence of v2 of the multistrange baryons confirms the number of constituent quark scaling previously observed for lighter hadrons. These results support the idea that a substantial fraction of the observed collective motion is developed at the early partonic stage in ultrarelativistic nuclear collisions at the Relativistic Heavy Ion Collider.

Baryon stopping and strangeness baryon production in a parton cascade model

International Nuclear Information System (INIS)

Nara, Yasushi

1999-01-01

A parton cascade model which is based on pQCD incorporating hard partonic scattering and dynamical hadronization scheme describes the space-time evolution of parton/hadron system produced by ultra-relativistic nuclear collisions. Hadron yield, baryon stopping and transverse momentum distribution are calculated and compared with experimental data at SPS energies. Using new version of parton cascade code VNI in which baryonic cluster formation is implemented, we calculate the net baryon number distributions and Λ yield. It is found that baryon stopping behavior at SPS energies is well accounted for within the parton cascade picture. As a consequence of the production of the baryon (u and d quark) rich parton matter, parton coalescence naturally explains the enhanced yield of Λ particle which has been observed in experiment. (author)

Performance of the ALICE secondary vertex b-tagging algorithm in p-Pb collisions

CERN Document Server

Kramárik, Lukáš

2016-01-01

The hot and dense nuclear matter, that is produced in heavy-ion collisions, could be studied by jets originating from beauty quarks. In-medium energy loss of these quarks provides information on several properties of the quark-gluon plasma, produced in ultra-relativistic heavy-ion collisions. Reconstructed jets are powerful tools, since they offer access to kinematics of these hard-scattered partons. Beauty hadrons are specific for their long lifetime, large mass and large-multiplicity decays. Due to the long lifetime beauty hadrons decay at displaced secondary vertices. In the ALICE experiment, secondary vertex properties are used to tag b-jets. The study of Monte Carlo based performance of the b-tagging algorithm for charged jets in p-Pb collisions at $\\sqrt{s_{\\mathrm{NN}}}=5.02$ TeV is discussed in proceedings.

Electromagnetic heavy-lepton pair production in relativistic heavy-ion collisions

Energy Technology Data Exchange (ETDEWEB)

Senguel, M.Y. [Atakent Mahallesi, 3. Etap, Halkali-Kuecuekcekmece, Istanbul (Turkey); Gueclue, M.C.; Mercan, Oe.; Karakus, N.G. [istanbul Technical University, Faculty of Science and Letters, Istanbul (Turkey)

2016-08-15

We calculate the cross sections of electromagnetic productions of muon- and tauon-pair productions from the ultra-relativistic heavy ion collisions. Since the Compton wavelengths of muon and tauon are comparable to the radius of the colliding ions, nuclear form factors play important roles for calculating the cross sections. Recent measurement (Abrahamyan et al., Phys Rev Lett 108:112502, 2012) indicates that the neutrons are differently distributed from the protons; therefore this affects the cross section of the heavy-lepton pair production. In order to see the effects of the neutron distributions in the nucleus, we used analytical expression of the Fourier transforms of the Wood-Saxon distribution. Cross section calculations show that the Wood-Saxon distribution function is more sensitive to the parameter R compared to the parameter a. (orig.)

Nuclear knowledge management

International Nuclear Information System (INIS)

2007-01-01

The management of nuclear knowledge has emerged as a growing challenge in recent years. The need to preserve and transfer nuclear knowledge is compounded by recent trends such as ageing of the nuclear workforce, declining student numbers in nuclear-related fields, and the threat of losing accumulated nuclear knowledge. Addressing these challenges, the IAEA promotes a 'knowledge management culture' through: - Providing guidance for policy formulation and implementation of nuclear knowledge management; - Strengthening the contribution of nuclear knowledge in solving development problems, based on needs and priorities of Member States; - Pooling, analysing and sharing nuclear information to facilitate knowledge creation and its utilization; - Implementing effective knowledge management systems; - Preserving and maintaining nuclear knowledge; - Securing sustainable human resources for the nuclear sector; and - Enhancing nuclear education and training

Measurements of Coulomb Cross Section for Production of Direct Electron-pairs by High Energy Ions at the CERN SPS

CERN Multimedia

2002-01-01

QED predicts copious direct electron pair production by ultrarelativistic heavy nuclei in a high Z medium such as nuclear emulsion. First order QED calculations (combined screening and non-screening) for this process show that 1000@+32 electron pairs above 100~keV energy) should be emitted for a total |1|6O track length of 10.9~m in nuclear emulsion at 200~GeV/AMU. Emulsion exposures with oxygen (and other nuclei if available) at 60 and 200~GeV/AMU will be used to calibrate the energy dependent cross section @s~@j~(1n~E)|2|-|3, whose exponent depends on atomic screening. The oxygen tracks in the developed emulsions will be scanned with a microscope, and the number of direct electron pairs will be counted for individual tracks. The exposed stacks will contain sufficient emulsion (and CR39 plastic to check for possible interactions) that adequate path length will be available for exposures to @$>$~10|4~ions at each energy and ion species. \\\\ \\\\ If the absolute value of this cross section is confirmed as large a...

Nuclear Power

International Nuclear Information System (INIS)

Douglas-Hamilton, J.; Home Robertson, J.; Beith, A.J.

1987-01-01

In this debate the Government's policy on nuclear power is discussed. Government policy is that nuclear power is the safest and cleanest way of generating electricity and is cheap. Other political parties who do not endorse a nuclear energy policy are considered not to be acting in the people's best interests. The debate ranged over the risks from nuclear power, the UK safety record, safety regulations, and the environmental effects of nuclear power. The Torness nuclear power plant was mentioned specifically. The energy policy of the opposition parties is strongly criticised. The debate lasted just over an hour and is reported verbatim. (UK)

Nuclear power generation and nuclear nonproliferation

International Nuclear Information System (INIS)

Walske, C.

1978-01-01

In the future outlook around year 2000 of nuclear power, thought must be given to fuel reprocessing and plutonium utilization. The adverse utilization of plutonium may be prevented by the means balanced with its economical value. As the method of less cost with lower effect of nonproliferation, combination of fuel reprocessing and fuel fabrication facilities and mixed plutonium/uranium processing are possible. As the method of more cost with higher effect of nonproliferation the maintenance of high radioactivity and inaccessibility of plutonium is conceivable. As for the agreeable methods in 2000, seven principles may be mentioned, such as the dependence upon the agreements among major nations and upon nuclear exporting countries. These are still inadequate, however. What is important is to provide with the sufficient safeguards to countries concerned to negate the need for nuclear weapons. Efforts are then necessary for leading nuclear countries to extend aids to other nuclear-oriented countries. (Mori, K.)

Nuclear Safety Regulations

International Nuclear Information System (INIS)

Novosel, N.; Prah, M.

2008-01-01

Beside new Ordinance on the control of nuclear material and special equipment ('Official Gazette' No. 15/08), from 2006 State Office for Nuclear Safety (SONS) adopted Ordinance on performing nuclear activities ('Official Gazette' No. 74/06) and Ordinance on special requirements which expert organizations must fulfil in order to perform certain activities in the field of nuclear safety ('Official Gazette' No. 74/06), based on Nuclear Safety Act ('Official Gazette' No. 173/03). The Ordinance on performing nuclear activities regulates the procedure of notification of the intent to perform nuclear activities, submitting the application for the issue of a licence to perform nuclear activities, and the procedure for issuing decisions on granting a licence to perform a nuclear activity. The Ordinance also regulates the content of the forms for notification of the intent to perform nuclear activities, as well as of the application for the issue of a licence to perform the nuclear activity and the method of keeping the register of nuclear activities. According to the Nuclear Safety Act, nuclear activities are the production, processing, use, storage, disposal, transport, import, export, possession or other handling of nuclear material or specified equipment. The Ordinance on special requirements which expert organizations must fulfil in order to perform certain activities in the field of nuclear safety regulates these mentioned conditions, whereas compliance is established by a decision passed by the SONS. Special requirements which expert organizations must fulfil in order to perform certain activities in the field of nuclear safety are organizational, technical, technological conditions and established system of quality assurance. In 2007, State Office for Nuclear Safety finalized the text of new Ordinance on conditions for nuclear safety and protection with regard to the siting, design, construction, use and decommissioning of a facility in which a nuclear activity is

Nuclear resisters

International Nuclear Information System (INIS)

1981-01-01

The booklet contains six papers by different authors, under the headings: dangers along the nuclear fuel cycle; the nuclear profiteers; the nuclear state is a police state; a non-disposable future (renewable energy sources, energy conservation); nuclear weapons - out of control; man made madness. (U.K.)

On Markov processes in the hadron-nuclear and nuclear-nuclear collisions at superhigh energies

International Nuclear Information System (INIS)

Lebedeva, A.A.; Rus'kin, V.I.

2001-01-01

In the article the possibility of the Markov processes use as simulation method for mean characteristics of hadron-nuclear and nucleus-nuclear collisions at superhigh energies is discussed. The simple (hadron-nuclear collisions) and non-simple (nucleus-nuclear collisions) non-uniform Markov process of output constant spectrum and absorption in a nucleon's nucleus-target with rapidity y are considered. The expression allowing to simulate the different collision modes were obtained

Nuclear power plants

International Nuclear Information System (INIS)

1985-01-01

Data concerning the existing nuclear power plants in the world are presented. The data was retrieved from the SIEN (Nuclear and Energetic Information System) data bank. The information are organized in table forms as follows: nuclear plants, its status and type; installed nuclear power plants by country; nuclear power plants under construction by country; planned nuclear power plants by country; cancelled nuclear power plants by country; shut-down nuclear power plants by country. (E.G.) [pt

Nuclear energy: considerations about nuclear trade

International Nuclear Information System (INIS)

Goes Fischer, M.D. de.

1988-01-01

A general view of historical aspects of nuclear energy and the arrangements to assure its use for peaceful purposes are presented. Then the internal character of nuclear energy in a juride context is demonstrated; some consideration about the international organizations and conventions and the Brazilian Legislation in the nuclear area are examined. It also deals with the political aspects of nuclear trade and the function of IAEA in this are. Furthermore the restrictions imposed by Non-Proliferation Treaty-NPT, the objectures of the Tlatelolco Treaty and ''London Club'' guidelines. Afterwards the bilateral cooperation under taken by countries and its agreements are discussed. Besides some aspects of agreements made between United States, France Germany and Brazil are discussed [pt

International Youth Nuclear Congress 2000: Youth, Future, Nuclear. Transactions

International Nuclear Information System (INIS)

2000-04-01

The publication has been set up as abstracts of the meeting dealing with different nuclear problems. In the work of the International Youth Nuclear Congress 2000 participated more than 200 young scientific works from 28 countries. The address discusses the following issues: Nuclear education and transfer of know-how; Nuclear technology; Political aspects; Environment and safety; Communication and public perception; Economics; Nuclear programs and technical cooperation; Fuel Cycle Challenges

International Youth Nuclear Congress 2000: Youth, Future, Nuclear. Transactions

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-04-01

The publication has been set up as abstracts of the meeting dealing with different nuclear problems. In the work of the International Youth Nuclear Congress 2000 participated more than 200 young scientific works from 28 countries. The address discusses the following issues: Nuclear education and transfer of know-how; Nuclear technology; Political aspects; Environment and safety; Communication and public perception; Economics; Nuclear programs and technical cooperation; Fuel Cycle Challenges.

Change of nuclear reactor installation in the first nuclear ship of Japan Nuclear Ship Development Agency

International Nuclear Information System (INIS)

1979-01-01

The written application concerning the change of nuclear reactor installation in the first nuclear ship was presented from the JNSDA to the prime minister on January 10, 1979. The contents of the change are the repair of the primary and secondary shields of the reactor, the additional installation of a storage tank for liquid wastes, and the extension of the period to stop the reactor in cold state. The inquiry from the prime minister to the Nuclear Safety Commission was made on June 9, 1979, through the examination of safety in the Nuclear Safety Bureau, Science and Technology Agency. The Nuclear Safety Commission instructed to the Committee for the Examination of Nuclear Reactor Safety on June 11, 1979, about the application of criteria stipulated in the law. The relevant letters and the drafts of examination papers concerning the technical capability and the safety in case of the change of nuclear reactor installation in the first nuclear ship are cited. The JNSDA and Sasebo Heavy Industries, Ltd. seem to have the sufficient technical capability to carry out this change. As the result of examination, it is recognized that the application presented by the JNSDA is in compliance with the criteria stipulated in the law concerning the regulation of nuclear raw materials, nuclear fuel materials and nuclear reactors. (Kako, I.)

Nuclear security and challenges at nuclear power plants. Part 1. Basis of nuclear security

International Nuclear Information System (INIS)

Demachi, Kazuyuki

2017-01-01

The tsunami that occurred in March 2011 associated with the 2011 off the Pacific coast of Tohoku Earthquake hit TEPCO Fukushima Daiichi Nuclear Power Station (1F). The 1F got into station blackout situation, and fell into reactor core meltdown due to inability of cooling down the reactor, eventually leading to the emission accident of radioactive substances over a wide range into the atmosphere, soil, seawater and the like. Through various media such as newspapers, TVs, and the Internet after the accident, important facilities for safety were explained with illustrations. Some of them included the contents that can suggest the causes that trigger the same accident as the 1F accident. It is an urgent task to strengthen security against the terrorism aimed at nuclear power facilities including nuclear power plants, and its realization is a serious problem in each country. This paper summarized nuclear security issues and solutions including explanation on the circumstances of the threat increase of nuclear terrorism that had begun before the 1F accident. The recent nuclear security summit reaffirmed that nuclear security is the basic responsibility of each country, and also reaffirmed the responsibility and importance of IAEA for international cooperation. This paper explains the definition of nuclear security, threat of terrorism, and the contents of the IAEA Nuclear Security Series (NSS), and points out that NSS is considered as the basis among basis that all the countries should share. (A.O.)

Nuclear analytical chemistry

Energy Technology Data Exchange (ETDEWEB)

Brune, D.; Forkman, B.; Persson, B.

1984-01-01

This book covers the general theories and techniques of nuclear chemical analysis, directed at applications in analytical chemistry, nuclear medicine, radiophysics, agriculture, environmental sciences, geological exploration, industrial process control, etc. The main principles of nuclear physics and nuclear detection on which the analysis is based are briefly outlined. An attempt is made to emphasise the fundamentals of activation analysis, detection and activation methods, as well as their applications. The book provides guidance in analytical chemistry, agriculture, environmental and biomedical sciences, etc. The contents include: the nuclear periodic system; nuclear decay; nuclear reactions; nuclear radiation sources; interaction of radiation with matter; principles of radiation detectors; nuclear electronics; statistical methods and spectral analysis; methods of radiation detection; neutron activation analysis; charged particle activation analysis; photon activation analysis; sample preparation and chemical separation; nuclear chemical analysis in biological and medical research; the use of nuclear chemical analysis in the field of criminology; nuclear chemical analysis in environmental sciences, geology and mineral exploration; and radiation protection.

Nuclear analytical chemistry

International Nuclear Information System (INIS)

Brune, D.; Forkman, B.; Persson, B.

1984-01-01

This book covers the general theories and techniques of nuclear chemical analysis, directed at applications in analytical chemistry, nuclear medicine, radiophysics, agriculture, environmental sciences, geological exploration, industrial process control, etc. The main principles of nuclear physics and nuclear detection on which the analysis is based are briefly outlined. An attempt is made to emphasise the fundamentals of activation analysis, detection and activation methods, as well as their applications. The book provides guidance in analytical chemistry, agriculture, environmental and biomedical sciences, etc. The contents include: the nuclear periodic system; nuclear decay; nuclear reactions; nuclear radiation sources; interaction of radiation with matter; principles of radiation detectors; nuclear electronics; statistical methods and spectral analysis; methods of radiation detection; neutron activation analysis; charged particle activation analysis; photon activation analysis; sample preparation and chemical separation; nuclear chemical analysis in biological and medical research; the use of nuclear chemical analysis in the field of criminology; nuclear chemical analysis in environmental sciences, geology and mineral exploration; and radiation protection

Iran's nuclear program - for power generation or nuclear weapons?

International Nuclear Information System (INIS)

Kippe, Halvor

2008-11-01

This report addresses the development of a nuclear infrastructure in Iran, and assessments are made on the near-term potential this infrastructure might yield of either nuclear power or nuclear arms production. The most significant facilities are treated in a more elaborate fashion, as these are assumed to have key roles in either a true civilian programme, or in the prospect of weapons-grade fissile material production. The future potential capacity for the latter is calculated under certain presumptions, both in the case that Iran focuses its efforts on uranium-based nuclear weapons, and in the case that it should choose the plutonium path to nuclear weapons. All the conclusions and findings in this report are based on technological considerations. This means that social or political assessments have not prevailed, rather the picture of Iran's nuclear programme is drawn through descriptions and assessments of facilities and systems, and their role in the bigger context. Definite conclusions have not been made as to whether Iran's nuclear programme currently is aimed towards nuclear arms or nuclear power. The secrecy surrounding some of the most prominent nuclear sites together with more or less credible allegations of purely weapons-related activities in the past, make it hard not to conclude that Iran until the disclosures in 2002 made as great an effort as it could on its way on developing nuclear weapons covertly. The scope of today's nuclear programme seems, on the other hand, most likely to be in part to help relieve the ever-increasing need for energy, although considerable deficits to this strategy are identified, at the same time as the Iranian people are united in a giant, high-prestige project in defiance of massive international pressure. Adding to this is a much-feared ability to rapidly being able to redirect their nuclear efforts, and develop nuclear arms in perhaps as little as one year. This so-called break-out scenario, where Iran presumably

Nuclear power and nuclear safety 2011

International Nuclear Information System (INIS)

Lauritzen, B.; Oelgaard, P.L.; Aage, H.K.; Kampmann, D.; Nystrup, P.E.; Thomsen, J.

2012-07-01

The report is the ninth report in a series of annual reports on the international development of nuclear power production, with special emphasis on safety issues and nuclear emergency preparedness. The report is written in collaboration between Risoe DTU and the Danish Emergency Management Agency. The report for 2011 covers the following topics: status of nuclear power production, regional trends, reactor development, safety related events, international relations and conflicts, and the Fukushima accident. (LN)

Nuclear data for nuclear reactor analyses

International Nuclear Information System (INIS)

Pearlstein, S.

1984-01-01

A discussion of nuclear data is presented emphasizing to what extent data are known and to what accuracy. The principal data of interest is that for neutron cross-sections. The changing status of data, evaluated nuclear data files and data validation and improvement are described. Although the discussion relates to nuclear data for reactor analysis may of the results also apply to fusion, accelerator, shielding, biomedical, space and defense studies. (U.K.)

Nuclear power and nuclear safety 2009

International Nuclear Information System (INIS)

Lauritzen, B.; Oelgaard, P.L.; Kampmann, D.; Nystrup, P.E.; Thorlaksen, B.

2010-05-01

The report is the seventh report in a series of annual reports on the international development of nuclear power production, with special emphasis on safety issues and nuclear emergency preparedness. The report is written in collaboration between Risoe DTU and the Danish Emergency Management Agency. The report for 2009 covers the following topics: status of nuclear power production, regional trends, reactor development, safety related events, international relations, conflicts and the European safety directive. (LN)

Nuclear Security for Floating Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Skiba, James M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Scherer, Carolynn P. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2015-10-13

Recently there has been a lot of interest in small modular reactors. A specific type of these small modular reactors (SMR,) are marine based power plants called floating nuclear power plants (FNPP). These FNPPs are typically built by countries with extensive knowledge of nuclear energy, such as Russia, France, China and the US. These FNPPs are built in one country and then sent to countries in need of power and/or seawater desalination. Fifteen countries have expressed interest in acquiring such power stations. Some designs for such power stations are briefly summarized. Several different avenues for cooperation in FNPP technology are proposed, including IAEA nuclear security (i.e. safeguards), multilateral or bilateral agreements, and working with Russian design that incorporates nuclear safeguards for IAEA inspections in non-nuclear weapons states

Nuclear science in the 20th century. Nuclear agricultural science

International Nuclear Information System (INIS)

Liu Jun; Xu Furong; Zheng Chunkai

2003-01-01

Nuclear science and technology have been successfully applied to many subjects, nuclear agriculture being one of the most important applications. We present a general review of the applications of nuclear radiation and nuclear tracer techniques in agriculture. The development of nuclear agriculture in China is also reviewed briefly

18 CFR 1316.9 - Nuclear energy hazards and nuclear incidents.

Science.gov (United States)

2010-04-01

... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Nuclear energy hazards... Text of Conditions and Certifications § 1316.9 Nuclear energy hazards and nuclear incidents. When so... documents or actions: Nuclear Energy Hazards and Nuclear Incidents (Applicable only to contracts for goods...

Themes in nuclear law; Temas de Derecho Nuclear

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

The nuclear law was analyzed during a workshop. The main aspects were: the law of population to access to information on nuclear energy and the relationship between the Regulator Organism and the nuclear power plants managers.

Combating nuclear terrorism in India: preventive nuclear forensic perspectives

International Nuclear Information System (INIS)

Raghav, N.K.; Lad, J.S.; Deshmukh, A.V.; Jagtap, S.S.

2014-01-01

Nuclear terrorism is constant threat to India by many terrorist organization and neighboring country. These organizations are directly or indirectly aided with nuclear material by terrorism supporting country. Such organization has a significant potential source for acquiring nuclear and other radioactive material. Possibility of leakage is widely feared because of the deteriorating law and order condition, great spur of nuclear proliferation after the cold war and disintegration of USSR. Terrorist could gain access to Nuclear and radioactive material and smuggle to India through porous borders. Preventive forensic approach in screening and searching nuclear and radioactive material will play cardinal role to prevent nuclear disaster happening in India. Future plans could be extracted from terrorists through their narco-tests, brain fingerprinting and a data base on this could be prepared, which could later be used to help prevent any attacks. In present paper authors strongly recommend setting up Preventive Forensic Units in India so that any internal or external nuclear attack could be aborted. (author)

Historical civilian nuclear accident based Nuclear Reactor Condition Analyzer

Science.gov (United States)

McCoy, Kaylyn Marie

There are significant challenges to successfully monitoring multiple processes within a nuclear reactor facility. The evidence for this observation can be seen in the historical civilian nuclear incidents that have occurred with similar initiating conditions and sequences of events. Because there is a current lack within the nuclear industry, with regards to the monitoring of internal sensors across multiple processes for patterns of failure, this study has developed a program that is directed at accomplishing that charge through an innovation that monitors these systems simultaneously. The inclusion of digital sensor technology within the nuclear industry has appreciably increased computer systems' capabilities to manipulate sensor signals, thus making the satisfaction of these monitoring challenges possible. One such manipulation to signal data has been explored in this study. The Nuclear Reactor Condition Analyzer (NRCA) program that has been developed for this research, with the assistance of the Nuclear Regulatory Commission's Graduate Fellowship, utilizes one-norm distance and kernel weighting equations to normalize all nuclear reactor parameters under the program's analysis. This normalization allows the program to set more consistent parameter value thresholds for a more simplified approach to analyzing the condition of the nuclear reactor under its scrutiny. The product of this research provides a means for the nuclear industry to implement a safety and monitoring program that can oversee the system parameters of a nuclear power reactor facility, like that of a nuclear power plant.

Nuclear energy

International Nuclear Information System (INIS)

2007-01-01

This digest document was written by members of the union of associations of ex-members and retired people of the Areva group (UARGA). It gives a comprehensive overview of the nuclear industry world, starting from radioactivity and its applications, and going on with the fuel cycle (front-end, back-end, fuel reprocessing, transports), the nuclear reactors (PWR, BWR, Candu, HTR, generation 4 systems), the effluents from nuclear facilities, the nuclear wastes (processing, disposal), and the management and safety of nuclear activities. (J.S.)

Nuclear chemistry

International Nuclear Information System (INIS)

Vertes, A.; Kiss, I.

1987-01-01

This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors

Nuclear chemistry

International Nuclear Information System (INIS)

Vertes, A.; Kiss, I.

1987-01-01

This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors. (Auth.)

Nuclear power

International Nuclear Information System (INIS)

Anon.

1980-01-01

The committee concludes that the nature of the proliferation problem is such that even stopping nuclear power completely could not stop proliferation completely. Countries can acquire nuclear weapons by means independent of commercial nuclear power. It is reasonable to suppose if a country is strongly motivated to acquire nuclear weapons, it will have them by 2010, or soon thereafter, no matter how nuclear power is managed in the meantime. Unilateral and international diplomatic measures to reduce the motivations that lead to proliferation should be high on the foreign policy agenda of the United States. A mimimum antiproliferation prescription for the management of nuclear power is to try to raise the political barriers against proliferation through misuse of nuclear power by strengthening the Non-Proliferation Treaty, and to seek to raise the technological barriers by placing fuel-cycle operations involving weapons-usable material under international control. Any such measures should be considered tactics to slow the spread of nuclear weapons and thus earn time for the exercise of statesmanship. The committee concludes the following about technical factors that should be considered in formulating nuclear policy: (1) rate of growth of electricity use is a primary factor; (2) growth of conventional nuclear power will be limited by producibility of domestic uranium sources; (3) greater contribution of nuclear power beyond 400 GWe past the year 2000 can only be supported by advanced reactor systems; and (4) several different breeder reactors could serve in principle as candidates for an indefinitely sustainable source of energy

Inseparable twins: nuclear bomb fuel and nuclear energy

International Nuclear Information System (INIS)

Ruff, T.; University of Melbourne, Melbourne

2006-01-01

The spread of nuclear power increases the number of nations and organisations with opportunities to make nuclear weapons or buy or steal the materials to make them. Global warming demands real solutions, not nuclear diversions and dangers.

International Nuclear Security Education Network (INSEN): Promoting nuclear security education

International Nuclear Information System (INIS)

Muhamad Samudi Yasir

2013-01-01

Full-text: The need for human resource development programmes in nuclear security was underlined at several International Atomic Energy Agency (IAEA) General Conferences and Board of Governors Meetings. Successive IAEA Nuclear Security Plans, the most recent of which was agreed by the Board of Governors in September 2009, give high priority to assisting States in establishing educational programmes in nuclear security in order to ensure the sustainability of nuclear security improvements. The current Nuclear Security Plan 1 covering 2010-2013 emphasizes on the importance of considering existing capacities at international, regional and national levels while designing nuclear security academic programmes. In the course of implementing the Plan, the IAEA developed a guide entitled Educational Programme in Nuclear Security (IAEA Nuclear Security Series No. 12) that consists of a model of a MAster of Science (M.Sc.) and a Certificate Programme in Nuclear Security. This guide was aims at assisting universities or other educational institutes to developed academic programmes in nuclear security. Independently, some universities already offered academic programmes covering some areas of nuclear security, while other universities have asked the IAEA to support the implementation of these programmes. In order to better address current and future request for assistance in this area, the IAEA establish a collaboration network-International Nuclear Security Education Network (INSEN), among universities who are providing nuclear security education or who are interested in starting an academic programme/ course(s) in nuclear security. Universiti Kebangsaan Malaysia (UKM) is a first local university became a member of INSEN since the beginning of the establishment. (author)

The separation of nuclear power from nuclear proliferation

International Nuclear Information System (INIS)

Starr, C.

1979-01-01

There exists world wide a strong common desire to limit nuclear weapons proliferation so as to inhibit or remove the threat of nuclear warfare. While this is a primary international political objective, there has also developed a secondary objective to limit any potential contribution to such nuclear weapons proliferation which might arise by the diversion of weapons material from the civilian nuclear power fuel cycle. This secondary objective is the basis of the present US government policy to defer the reprocessing of nuclear fuels anywhere. This policy has been generally recognized as a temporary expedient to provide time for international reexamination of the problems of weapons proliferation associated with nuclear power. A successful development of the proposed combination of the Fast Breeder Reactor and the Civex fuel reprocessing facility would provide an economical nuclear power source for many centuries which inherently separates nuclear power from the issue of weapons material diversion and proliferation. Further, by so doing, it permits great flexibility in international and national planning for nuclear power, as the issues of fuel dependence and terrorist and subnational diversions disappear. In addition, the expansion of the FBR/Civex system would eat into the LWR spent fuel stockpile, diminishing steadily this relatively accessible plutonium source. And finally, a rapid development of the FBR/Civex for the above reasons would substantially reduce the worldwide concern as to the adequacy of uranium ore supply. (Auth.)

General Nuclear Medicine

Science.gov (United States)

... Resources Professions Site Index A-Z General Nuclear Medicine Nuclear medicine imaging uses small amounts of radioactive ... of General Nuclear Medicine? What is General Nuclear Medicine? Nuclear medicine is a branch of medical imaging ...

Introducing nuclear power into currently non-nuclear states

International Nuclear Information System (INIS)

Claassen, Gert

2007-01-01

As the nuclear renaissance gains momentum, many countries that currently have no nuclear power plants will begin to consider introducing them. It is anticipated that smaller reactors such as the Pebble Bed Modulator Reactor (PBMR) will not only be sold to current nuclear states to also to states where there is currently no nuclear experience. A range of issues would have to be considered for nuclear plants to be solid to non-nuclear states, such as the appropriate regulatory environment, standardization and codes, non-proliferation, security of supply, obtaining experienced merchant operators, appropriate financial structures and education and training. The paper considers nine major issues that need to be addressed by governments and vendors alike. International cooperation by organisations such as the IAEA, financial institutions and international suppliers will be required to ensure that developing countries as well as developed ones share the benefits of the nuclear renaissance. The opportunities that the nuclear industry affords to develop local skills, create job opportunities and to develop local manufacturing industries are among the important reasons that the South African Government has decided to support and fund the development of the Pebble Bed Modular Reactor project. These considerations are included in the paper. (author)

International conference: Features of nuclear excitation states and mechanisms of nuclear reactions. 51. Meeting on nuclear spectroscopy and nuclear structure. The book of abstracts

International Nuclear Information System (INIS)

2001-01-01

Results of the LI Meeting on Nuclear Spectroscopy and Nuclear Structure are presented. Properties of excited states of atomic nuclei and mechanisms of nuclear reactions are considered. Studies on the theory of nucleus and fundamental interactions pertinent to experimental study of nuclei properties and mechanisms of nuclear reactions, technique and methods of experiment, application of nuclear-physical method, are provided [ru

Nuclear energy and the nuclear energy industry

International Nuclear Information System (INIS)

Bromova, E.; Vargoncik, D.; Sovadina, M.

2013-01-01

A popular interactive multimedia publication on nuclear energy in Slovak. 'Nuclear energy and energy' is a modern electronic publication that through engaging interpretation, combined with a number of interactive elements, explains the basic principles and facts of the peaceful uses of nuclear energy. Operation of nuclear power plants, an important part of the energy resources of developed countries, is frequently discussed topic in different social groups. Especially important is truthful knowledgeability of the general public about the benefits of technical solutions, but also on the risks and safety measures throughout the nuclear industry. According to an online survey 'Nuclear energy and energy' is the most comprehensive electronic multimedia publication worldwide, dedicated to the popularization of nuclear energy. With easy to understand texts, interactive and rich collection of accessories stock it belongs to modern educational and informational titles of the present time. The basic explanatory text of the publication is accompanied by history and the present time of all Slovak nuclear installations, including stock photos. For readers are presented the various attractions legible for the interpretation, which help them in a visual way to make a more complete picture of the concerned issue. Each chapter ends with a test pad where the readers can test their knowledge. Whole explanatory text (72 multimedia pages, 81,000 words) is accompanied by a lot of stock of graphic materials. The publication also includes 336 photos in 60 thematic photo galleries, 45 stock charts and drawings, diagrams and interactive 31 videos and 3D models.

Nuclear power and nuclear safety 2012

International Nuclear Information System (INIS)

Lauritzen, B.; Nonboel, E.; Israelson, C.; Kampmann, D.; Nystrup, P.E.; Thomsen, J.

2013-11-01

The report is the tenth report in a series of annual reports on the international development of nuclear power production, with special emphasis on safety issues and nuclear emergency preparedness. The report is prepared in collaboration between DTU Nutech and the Danish Emergency Management Agency. The report for 2012 covers the following topics: status of nuclear power production, regional trends, reactor development, safety related events, international relations and conflicts, and the results of the EU stress test. (LN)

Nuclear Law

International Nuclear Information System (INIS)

Wiesbauer, Bruno

1978-01-01

This book is the first attempt of a comprehensive compilation of national Austrian Nuclear Law (Nuclear Liability Act; Radiation protection Act, Radiation Protection Ordinance, Security Control Act, Act on the uses of Nuclear Energy - Zwentendorf Nuclear Power Plant) and the most important international agreements to which Austria is a party. Furthermore, the book contains the most important Nuclear Liability Conventions to which Austria is not yet a party, but which are applicable in neighbouring; the Paris Convention served as a model for the national Nuclear Liability Act and may be used for its interpretation. The author has translated a number of international instruments into German, such as the Expose des Motifs of the Paris Convention. (NEA) [fr

Nuclear energy

International Nuclear Information System (INIS)

Panait, A.

1994-01-01

This is a general report presenting the section VII entitled Nuclear Power of the National Conference on Energy (CNE '94) held in Neptun, Romania, on 13-16 June 1994. The problems addressed were those relating to electric power produced by nuclear power plant, to heat secondary generation, to quality assurance, to safety, etc. A special attention was paid to the commissioning of the first Romanian nuclear power unit, the Cernavoda-1 reactor of CANDU type. The communications were grouped in four subsections. These were: 1. Quality assurance, nuclear safety, and environmental protection; 2. Nuclear power plant, commissioning, and operation; 3. Nuclear power plant inspection, maintenance, and repairs, heavy water technology; 4. Public opinion education. There were 22 reports, altogether

Nuclear Energy Scientific, technical and social perspectives of nuclear-electrical conversion

International Nuclear Information System (INIS)

Suarez Antola, R.

2009-01-01

The book begins with a brief review of basic knowledge historic milestones, radiation physics, biological effects of radiation and radioprotection, and nuclear physics. Then, several subjects in nuclear reactor engineering and nuclear power plants are introduced: a brief description of nuclear reactors and systems in a nuclear power plant, neutron physics, thermal hydraulics (including the thermodynamics of the whole nuclear power plant), nuclear fuels and fuel cycles, dynamic and control of nuclear reactors and nuclear power plant, safety of nuclear reactors, operation of power plants, decisions related with a nuclear power station (including sitting, economic and financial aspects, risks and detriments assessment), and a brief survey of future technologies. In the last chapter, the book enters into other subjects (in part of a philosophical nature) that relate, from the standpoint of energy, social and environmental problems with political issues and current world views

Nuclear and radiological safety nuclear power nuclear fuel cycle and waste management

International Nuclear Information System (INIS)

1997-05-01

This catalogue lists all sales publications of the International Atomic Energy Agency dealing with Nuclear and Radiological Safety, Nuclear Power and Nuclear Fuel Cycle and Waste Management and issued during the period of 1995-1996. Most publications are in English. Proceedings of conferences, symposia and panels of experts may contain some papers in languages other than English (Arabic, Chinese, French, Russian or Spanish), but all these papers have abstracts in English

Nuclear science

International Nuclear Information System (INIS)

1989-01-01

This fact sheet answers specific questions about the Department of Energy's possible acquisition and conversion of a partially completed commercial nuclear power plant to a nuclear materials production facility. The nuclear power plant is the Washington Nuclear Plant number sign 1 owned by the Washington Public Power Supply System and is located on DOE's Hanford Reservation near Richland, Washington

Nuclear science

International Nuclear Information System (INIS)

1989-04-01

This report answers questions about the Department of Energy's possible acquisition and conversion of a partially completed commercial nuclear power plant to a nuclear materials production facility. The nuclear power plant is the Washington Nuclear Plant No.1 owned by the Washington Public Power Supply System and is located on DOE's Hanford Reservation near Richland, Washington

Nuclear measurements

International Nuclear Information System (INIS)

Schenkel, R.

2005-01-01

Nuclear measurements play a fundamental role in the development of nuclear technology and the assurance of its peaceful use. They are also required in many non-power nuclear applications such as in nuclear medicine, agriculture, environmental protection, etc. This presentation will show examples of most recent advances in measurement methodology or technology in the areas described below. The Generation IV International Forum has selected six innovative reactor systems as candidates for a next generation of sustainable, economic and safe nuclear energy systems. The choice of the best options relies heavily on the availability of accurate nuclear data that can only be obtained, in an international effort, using highly specialised facilities. Significant efforts are being directed towards the partitioning and transmutation of highly active nuclear waste. Different concepts involving fast reactors or accelerator-driven systems are being studied in view of their transmutation capabilities. State of the art equipment has been developed to assess basic properties of nuclear fuel at very high burn-up; some fine examples of this work will be shown. Physical and chemical methods play a crucial role in the detection and identification of radioisotopes used in various stages of the nuclear fuel cycle. Radiation measurement techniques are used, for example, to monitor the quantities of uranium, plutonium and other actinide elements in fuel enrichment and reprocessing facilities. Another field of application of physical and chemical methods is the characterisation of nuclear material seized from illicit trafficking. Seized material has to be analysed in order to obtain clues on its origin and intended use and to prevent diversion of nuclear material from the same source in the future. A recent highlight in basic physics relates to nuclear fission and transmutation with high intensity lasers. Ultra-fast high intensity lasers can produce high energy (tens of MeV) photons through

Sunken nuclear submarines

International Nuclear Information System (INIS)

Eriksen, V.O.

1990-01-01

The increasing number of accidents with nuclear submarines is a worriment to the general public. Five nuclear submarines are resting on the bottom of the North Atlantic. Design information on nuclear propulsion plants for submarines is classified. The author describes a potential generic nuclear submarine propulsion plant. Design information from the civilian nuclear industry, nuclear power plants, research reactors, nuclear cargo vessels and nuclear propelled icebreakers are used for illustration of relevant problems. A survey is given of nuclear submarines. Factors influencing the accident risks and safety characteristics of nuclear submarines are considered, and potential accident scenarios are described. The fission product content of the nuclear plant can be estimated, '' source terms'' can be guessed and potential release rates can be judged. The mechanisms of dispersion in the oceans is reviewed and compared with the dumping of radioactive waste in the Atlantic and other known releases. 46 refs., 49 figs., 14 tabs

A review of experimental results obtained in Au-Au collisions at the RHIC-BNL energies using BRAHMS experimental set-up

International Nuclear Information System (INIS)

Jipa, Alexandru

2003-01-01

Ultrarelativistic heavy ion collisions are useful tools to investigate highly excited dense nuclear matter. At sufficiently high temperature, nuclear matter is expected to undergo a phase transition to quark-gluon plasma. Therefore, new experiments have been proposed to investigate the behaviour of the highly excited dense nuclear matter. One of the experiments performed at the Relativistic Heavy Ion Collider from Brookhaven National Laboratory is the BRAHMS Experiment. In the three running years many experimental data have been obtained. These data permitted to establish significant experimental results on charged pion, charged kaon, proton and antiproton production in Au-Au collisions at 130 A GeV and 200 A GeV in CMS. The present work summarizes the main experimental results on charged particle multiplicities, rapidity distributions, momentum spectra, antiparticle to particle ratios and connects these results with some interesting physical quantities. Their dependencies on the available energies in the CMS in similar collisions are included. Interesting behaviours with the increase of this energy are reported. The most interesting are related to the behaviour of the antiproton to proton ratio on the collision centrality and on the available energy in the centre of mass system, the strangeness production, Coulomb repulsion and slope parameters of the momentum spectra. A few new steps in the knowledge of the behaviour of the highly excited and dense nuclear matter can be reported. (authors)

Nuclear reactions video (knowledge base on low energy nuclear physics)

International Nuclear Information System (INIS)

Zagrebaev, V.; Kozhin, A.

1999-01-01

The NRV (nuclear reactions video) is an open and permanently extended global system of management and graphical representation of nuclear data and video-graphic computer simulation of low energy nuclear dynamics. It consists of a complete and renewed nuclear database and well known theoretical models of low energy nuclear reactions altogether forming the 'low energy nuclear knowledge base'. The NRV solves two main problems: 1) fast and visualized obtaining and processing experimental data on nuclear structure and nuclear reactions; 2) possibility for any inexperienced user to analyze experimental data within reliable commonly used models of nuclear dynamics. The system is based on the realization of the following principal things: the net and code compatibility with the main existing nuclear databases; maximal simplicity in handling: extended menu, friendly graphical interface, hypertext description of the models, and so on; maximal visualization of input data, dynamics of studied processes and final results by means of real three-dimensional images, plots, tables and formulas and a three-dimensional animation. All the codes are composed as the real Windows applications and work under Windows 95/NT

Nuclear Forensics: Scientific Analysis Supporting Law Enforcement and Nuclear Security Investigations.

Science.gov (United States)

Keegan, Elizabeth; Kristo, Michael J; Toole, Kaitlyn; Kips, Ruth; Young, Emma

2016-02-02

Nuclear forensic science, or "nuclear forensic", aims to answer questions about nuclear material found outside of regulatory control. In this Feature, we provide a general overview of nuclear forensics, selecting examples of key "nuclear forensic signatures" which have allowed investigators to determine the identity of unknown nuclear material in real investigations.

Nuclear Symbiosis - A Means to Achieve Sustainable Nuclear Growth while Limiting the Spread of Sensitive Nuclear Technology

International Nuclear Information System (INIS)

Shropshire, David

2009-01-01

Global growth of nuclear energy in the 21st century is creating new challenges to limit the spread of nuclear technology without hindering adoption in countries now considering nuclear power. Independent nuclear states desire autonomy over energy choices and seek energy independence. However, this independence comes with high costs for development of new indigenous fuel cycle capabilities. Nuclear supplier states and expert groups have proposed fuel supply assurance mechanisms such as fuel take-back services, international enrichment services and fuel banks in exchange for recipient state concessions on the development of sensitive technologies. Nuclear states are slow to accept any concessions to their rights under the Non-Proliferation Treaty. To date, decisions not to develop indigenous fuel cycle capabilities have been driven primarily by economics. However, additional incentives may be required to offset a nuclear state's perceived loss of energy independence. This paper proposes alternative economic development incentives that could help countries decide to forgo development of sensitive nuclear technologies. The incentives are created through a nuclear-centered industrial complex with 'symbiotic' links to indigenous economic opportunities. This paper also describes a practical tool called the 'Nuclear Materials Exchange' for identifying these opportunities.

Nuclear Symbiosis - A Means to Achieve Sustainable Nuclear Growth while Limiting the Spread of Sensititive Nuclear Technology

Energy Technology Data Exchange (ETDEWEB)

David Shropshire

2009-09-01

Global growth of nuclear energy in the 21st century is creating new challenges to limit the spread of nuclear technology without hindering adoption in countries now considering nuclear power. Independent nuclear states desire autonomy over energy choices and seek energy independence. However, this independence comes with high costs for development of new indigenous fuel cycle capabilities. Nuclear supplier states and expert groups have proposed fuel supply assurance mechanisms such as fuel take-back services, international enrichment services and fuel banks in exchange for recipient state concessions on the development of sensitive technologies. Nuclear states are slow to accept any concessions to their rights under the Non-Proliferation Treaty. To date, decisions not to develop indigenous fuel cycle capabilities have been driven primarily by economics. However, additional incentives may be required to offset a nuclear state’s perceived loss of energy independence. This paper proposes alternative economic development incentives that could help countries decide to forgo development of sensitive nuclear technologies. The incentives are created through a nuclear-centered industrial complex with “symbiotic” links to indigenous economic opportunities. This paper also describes a practical tool called the “Nuclear Materials Exchange” for identifying these opportunities.

Nuclear energy and nuclear weapons proliferation

International Nuclear Information System (INIS)

1989-01-01

A summary of the report dispatched in the middle of 1978 by the Atlantic Council of United States, organized by North American citizens, is presented. The report considers the relation between the production of nucleoelectric energy and the capacity of proliferation of nuclear weapons. The factors which affect the grade of proliferation risk represented by the use of nuclear energy in the world comparing this risk with the proliferation risks independently of nuclear energy, are examined. (M.C.K.) [pt

Nuclear Security Recommendations on Physical Protection of Nuclear Material and Nuclear Facilities (INFCIRC/225/Revision 5): Recommendations

International Nuclear Information System (INIS)

2011-01-01

This publication, Revision 5 of Physical Protection of Nuclear Material and Nuclear Facilities (INFCIRC/225), is intended to provide guidance to States and their competent authorities on how to develop or enhance, implement and maintain a physical protection regime for nuclear material and nuclear facilities, through the establishment or improvement of their capabilities to implement legislative and regulatory programmes. The recommendations presented in this publication reflect a broad consensus among IAEA Member States on the requirements which should be met for the physical protection of nuclear materials and nuclear facilities.

Nuclear winter: Global consequences of multiple nuclear explosions

International Nuclear Information System (INIS)

Turco, R.P.; Toon, O.B.; Ackerman, T.P.; Pollack, J.B.; Sagan, C.

1984-01-01

Concern has been raised over the short- and long-term consequences of the dust, smoke, radioactivity, and toxic vapors that would be generated by a nuclear war. The discovery that dense clouds of soil particles may have played a major role in past mass extinctions of life on Earth has encouraged the reconsideration of nuclear war effects. These developments have led the authors to calculate, using new data and improved models, the potential global environmental effects of dust and smoke clouds (henceforth referred to as nuclear dust and smoke) generated in a nuclear war. They neglect the short-term effects of blast, fire, and radiation. Most of the world's population could probably survive the initial nuclear exchange and would inherit the postwar environment. Accordingly, the longer-term and global-scale aftereffects of nuclear war might prove to be as important as the immediate consequences of the war

Choosing nuclear engineering: A survey of nuclear engineering undergraduates

International Nuclear Information System (INIS)

Shillenn, J.K.; Klevans, E.H.

1988-01-01

Maintaining a reliable pool of qualified nuclear engineering graduates depends on the ability of nuclear engineering undergraduate programs to recruit students. With the prospect of declining enrollments in nuclear engineering it is important for nuclear engineering programs to know what factors influence students to choose nuclear engineering as an undergraduate major and why they choose a particular undergraduate program. This type of information can be very important to nuclear engineering programs that develop recruiting strategies. To provide some insight into this area, a questionnaire was designed and given to undergraduate nuclear engineering students at Pennsylvania State University. The purpose of the survey was to provide information on the reasons that students picked nuclear engineering as a career and chose to attend Penn State. The questionnaire was given to 27 students in their junior year during the spring semester of 1987 and again to 35 junior students during the spring semester of 1988. There was little difference except as noted between the two groups on their responses to the questionnaire. A partial listing of the survey results is provided

Nuclear option

Energy Technology Data Exchange (ETDEWEB)

Kemm, K R

1978-05-01

The global outlook is that nuclear reactors are here to stay and South Africa has already entered the nuclear power stakes. This article discusses the rocketing oil prices, and the alternatives that can be used in power generation, the good safety record of the nuclear industry and the effect that South Africa's first nuclear power station should have on the environment.

Nuclear medicine

International Nuclear Information System (INIS)

Lentle, B.C.

1986-01-01

Several growth areas for nuclear medicine were defined. Among them were: cardiac nuclear medicine, neuro-psychiatric nuclear medicine, and cancer diagnosis through direct tumor imaging. A powerful new tool, Positron Emission Tomography (PET) was lauded as the impetus for new developments in nuclear medicine. The political environment (funding, degree of autonomy) was discussed, as were the economic and scientific environments

High-Frequency Dynamic Nuclear Polarization in the Nuclear Rotating Frame

DEFF Research Database (Denmark)

Farrar, C. T.; Hall, D. A.; Gerfen, G. J.

2000-01-01

A proton dynamic nuclear polarization (DNP) NMR signal enhancement (ϵ) close to thermal equilibrium, ϵ = 0.89, has been obtained at high field (B0 = 5 T, νepr = 139.5 GHz) using 15 mM trityl radical in a 40:60 water/glycerol frozen solution at 11 K. The electron-nuclear polarization transfer...... is performed in the nuclear rotating frame with microwave irradiation during a nuclear spin-lock pulse. The growth of the signal enhancement is governed by the rotating frame nuclear spin–lattice relaxation time (T1ρ), which is four orders of magnitude shorter than the nuclear spin–lattice relaxation time (T1n......). Due to the rapid polarization transfer in the nuclear rotating frame the experiment can be recycled at a rate of 1/T1ρ and is not limited by the much slower lab frame nuclear spin–lattice relaxation rate (1/T1n). The increased repetition rate allowed in the nuclear rotating frame provides an effective...

Nuclear waste management, reactor decommisioning, nuclear liability and public attitudes

International Nuclear Information System (INIS)

Green, R.E.

1982-01-01

This paper deals with several issues that are frequently raised by the public in any discussion of nuclear energy, and explores some aspects of public attitudes towards nuclear-related activities. The characteristics of the three types of waste associated with the nuclear fuel cycle, i.e. mine/mill tailings, reactor wastes and nuclear fuel wastes, are defined, and the methods currently being proposed for their safe handling and disposal are outlined. The activities associated with reactor decommissioning are also described, as well as the Canadian approach to nuclear liability. The costs associated with nuclear waste management, reactor decommissioning and nuclear liability are also discussed. Finally, the issue of public attitudes towards nuclear energy is addressed. It is concluded that a simple and comprehensive information program is needed to overcome many of the misconceptions that exist about nuclear energy and to provide the public with a more balanced information base on which to make decisions

New nuclear projects in the world. Sustainable Nuclear Energy

International Nuclear Information System (INIS)

Leon, P. T.

2011-01-01

Nuclear power has experienced a major boom in the last few years, primarily because it is a non-CO 2 emitting energy source, it can be produced at competitive costs and it can boost a country's security of supply. there are still two issues to be addressed in relation to the currently used technologies: the degree to which the energy content of nuclear fuel is used, and wastes. A solution to both these aspects would ut nuclear power in the category of sustainable energy. The article provides details on current nuclear plans in the wold, the impact of the Fukushima accident on different countries nuclear plans and the European initiatives for sustainable nuclear energy development. (Author)

Nuclear fuels

International Nuclear Information System (INIS)

Gangwani, Saloni; Chakrabortty, Sumita

2011-01-01

Nuclear fuel is a material that can be consumed to derive nuclear energy, by analogy to chemical fuel that is burned for energy. Nuclear fuels are the most dense sources of energy available. Nuclear fuel in a nuclear fuel cycle can refer to the fuel itself, or to physical objects (for example bundles composed of fuel rods) composed of the fuel material, mixed with structural, neutron moderating, or neutron reflecting materials. Long-lived radioactive waste from the back end of the fuel cycle is especially relevant when designing a complete waste management plan for SNF. When looking at long-term radioactive decay, the actinides in the SNF have a significant influence due to their characteristically long half-lives. Depending on what a nuclear reactor is fueled with, the actinide composition in the SNF will be different. The following paper will also include the uses. advancements, advantages, disadvantages, various processes and behavior of nuclear fuels

Nuclear networking.

Science.gov (United States)

Xie, Wei; Burke, Brian

2017-07-04

Nuclear lamins are intermediate filament proteins that represent important structural components of metazoan nuclear envelopes (NEs). By combining proteomics and superresolution microscopy, we recently reported that both A- and B-type nuclear lamins form spatially distinct filament networks at the nuclear periphery of mouse fibroblasts. In particular, A-type lamins exhibit differential association with nuclear pore complexes (NPCs). Our studies reveal that the nuclear lamina network in mammalian somatic cells is less ordered and more complex than that of amphibian oocytes, the only other system in which the lamina has been visualized at high resolution. In addition, the NPC component Tpr likely links NPCs to the A-type lamin network, an association that appears to be regulated by C-terminal modification of various A-type lamin isoforms. Many questions remain, however, concerning the structure and assembly of lamin filaments, as well as with their mode of association with other nuclear components such as peripheral chromatin.

Nuclear weapons modernizations

Energy Technology Data Exchange (ETDEWEB)

Kristensen, Hans M. [Federation of American Scientists, Washington, DC (United States)

2014-05-09

This article reviews the nuclear weapons modernization programs underway in the world's nine nuclear weapons states. It concludes that despite significant reductions in overall weapons inventories since the end of the Cold War, the pace of reductions is slowing - four of the nuclear weapons states are even increasing their arsenals, and all the nuclear weapons states are busy modernizing their remaining arsenals in what appears to be a dynamic and counterproductive nuclear competition. The author questions whether perpetual modernization combined with no specific plan for the elimination of nuclear weapons is consistent with the nuclear Non-Proliferation Treaty and concludes that new limits on nuclear modernizations are needed.

Introducing nuclear power into currently non-nuclear states

International Nuclear Information System (INIS)

Gert, Claassen

2007-01-01

As the nuclear renaissance gains momentum, many countries that currently have no nuclear power plants will begin to consider introducing them. It is anticipated that smaller reactors such as the Pebble Bed Modular Reactor (PBMR) will not only be sold to current nuclear states to also to states where there is currently no nuclear experience. A range of issues would have to be considered for nuclear plants to be sold to non-nuclear states, such as the appropriate regulatory environment, standardization and codes, non-proliferation, security of supply, obtaining experienced merchant operators, appropriate financial structures and education and training. The paper considers nine major issues that need to be addressed by governments and vendors alike: 1) political enabling framework, 2) regulatory framework, 3) responsible owner, 4) responsible operator, 5) finance, 6) contact management, 7) fuel supply and waste management framework, 8) training and education, and 9) industrial infrastructure. International cooperation by organisations such as the IAEA, financial institutions and international suppliers will be required to ensure that developing countries as well as developed ones share the benefits of the nuclear renaissance. The opportunities that the nuclear industry affords to develop local skills, create job opportunities and to develop local manufacturing industries are among the important reasons that the South African Government has decided to support and fund the development of the Pebble Bed Modular Reactor project. (author)

Muon nuclear fusion and low temperature nuclear fusion

International Nuclear Information System (INIS)

Nagamine, Kanetada

1990-01-01

Low temperature (or normal temperature) nuclear fusion is one of the phenomena causing nuclear fusion without requiring high temperature. In thermal nuclear fusion, the Coulomb barrier is overcome with the help of thermal energy, but in the low temperature nuclear fusion, the Coulomb barrier is neutralized by the introduction of the particles having larger mass than electrons and negative charges, at this time, if two nuclei can approach to the distance of 10 -13 cm in the neutral state, the occurrence of nuclear fusion reaction is expected. As the mass of the particles is heavier, the neutral region is smaller, and nuclear fusion is easy to occur. The particles to meet this purpose are the electrons within substances and muons. The research on muon nuclear fusion became suddenly active in the latter half of 1970s, the cause of which was the discovery of the fact that the formation of muons occurs resonantly rapidly in D-T and D-D systems. Muons are the unstable elementary particles having the life of 2.2 μs, and they can have positive and negative charges. In the muon catalyzed fusion, the muons with negative charge take part. The principle of the muon catalyzed fusion, its present status and future perspective, and the present status of low temperature nuclear fusion are reported. (K.I.)

Parvoviral nuclear import: bypassing the host nuclear-transport machinery.

Science.gov (United States)

Cohen, Sarah; Behzad, Ali R; Carroll, Jeffrey B; Panté, Nelly

2006-11-01

The parvovirus Minute virus of mice (MVM) is a small DNA virus that replicates in the nucleus of its host cells. However, very little is known about the mechanisms underlying parvovirus' nuclear import. Recently, it was found that microinjection of MVM into the cytoplasm of Xenopus oocytes causes damage to the nuclear envelope (NE), suggesting that the nuclear-import mechanism of MVM involves disruption of the NE and import through the resulting breaks. Here, fluorescence microscopy and electron microscopy were used to examine the effect of MVM on host-cell nuclear structure during infection of mouse fibroblast cells. It was found that MVM caused dramatic changes in nuclear shape and morphology, alterations of nuclear lamin immunostaining and breaks in the NE of infected cells. Thus, it seems that the unusual nuclear-import mechanism observed in Xenopus oocytes is in fact used by MVM during infection of host cells.

Towards sustainable nuclear energy: Putting nuclear physics to work

International Nuclear Information System (INIS)

Koning, A.J.; Rochman, D.

2008-01-01

We have developed a new method to propagate the uncertainties of fundamental nuclear physics models and parameters to the design and performance parameters of future, clean nuclear energy systems. Using Monte Carlo simulation, it is for the first time possible to couple these two fields at the extremes of nuclear science without any loss of information in between. With the help of a large database of nuclear reaction measurements, we have determined the uncertainties of theoretical nuclear reaction models such as the optical, compound nucleus, pre-equilibrium and fission models. A similar assessment is done for the parameters that describe the resolved resonance range. Integrating this into one simulation program enables us to describe all open channels in a nuclear reaction, including a complete handling of uncertainties. Moreover, in one and the same process, values and uncertainties of nuclear reactor parameters are computed. This bypasses all the intermediate steps which have been used so far in nuclear data and reactor physics. Two important results emerge from this work: (a) we are able to quantify the required quality of theoretical nuclear reaction models directly from the reactor design requirements and (b) our method leads to a deviation from the commonly assumed normal distribution for uncertainties of safety related reactor parameters, and this should be taken into account for future nuclear energy development. In particular, calculated k eff distributions show a high-value tail for fast reactor spectra

The development of nuclear power and nuclear manpower training in China

International Nuclear Information System (INIS)

Yang Lin; Xu Xiyue

2000-01-01

There are two nuclear power plants (NPP) in operation in China. The Qinshan NPP was the first that was constructed by China's own efforts and went into operation on 1991. The Daya Bay NPP was constructed using foreign funds, technology and went into operation on 1994. Four nuclear power projects with 8 units were initiated during the State Ninth Five-years Plan. The 8 units are expected for commercial operation between 2002 and 2005. China is preparing for the Tenth Five-Year Plan, in which China will develop the nuclear power at a moderate pace. The 13 universities and colleges were offering nuclear science educations. The students from these universities and college can meet the needs of nuclear institutes and enterprises. China National Nuclear Corporation (CNNC) owns the Graduated School of Nuclear Industry and the Nuclear Industry Administrative Cadre College, which will turn into the nuclear training center in future. Besides, CNNC also owns 4 institutions awarding Doctorate and 9 institutes awarding Master Degree. Many programs for education and training carried out by CNNC are presented, such as direct education supported by CNNC's finances, on job training, education for the second bachelor degree, training for senior economic professionals, research course for senior professionals, short time training course and training for license. China trained nuclear personnel by international cooperation with other countries both through multilateral and bilateral cooperation programs. CNNC has established scientific and economic ties with over 40 countries. CNNC has held diversified training for nuclear industry professionals with our own efforts and with the support from the State for many years. Today, the rapid development of nuclear industry needs more professionals. We must make greater efforts to enhance human resources development. Nuclear Safety is very important for nuclear energy development. Nuclear safety is closely related to each person who works in

Nuclear disarmament or survival of nuclear arms?

International Nuclear Information System (INIS)

Stroot, J.P.

1997-01-01

START II has not yet been ratified by the US or Russian parliaments. Doubts may be raised over whether it will ever be. In the best case there will be more than 20,000 nuclear warheads in the arsenals of these two countries by the year 2003. All five nuclear states consider that nuclear weapons are an essential component of their national defense. It might sound childish but, the whole story is is so often childish: the five powers refuse to break their nuclear toys. They take even all possible measures to maintain and improve them and to ensure the survivability of their arsenals. To prepare for the next arms race..

Siting of nuclear facilities. Selections from Nuclear Safety

Energy Technology Data Exchange (ETDEWEB)

Buchanan, J.R.

1976-07-01

The report presented siting policy and practice for nuclear power plants as developed in the U.S. and abroad. Twenty-two articles from Nuclear Safety on this general topic are reprinted since they provide a valuable reference source. The appendices also include reprints of some relevant regulatory rules and guides on siting. Advantages and disadvantages of novel siting concepts such as underground containment, offshore siting, and nuclear energy parks are addressed. Other topics include site criteria, risk criteria, and nuclear ship criteria.

Siting of nuclear facilities. Selections from Nuclear Safety

International Nuclear Information System (INIS)

Buchanan, J.R.

1976-07-01

The report presented siting policy and practice for nuclear power plants as developed in the U.S. and abroad. Twenty-two articles from Nuclear Safety on this general topic are reprinted since they provide a valuable reference source. The appendices also include reprints of some relevant regulatory rules and guides on siting. Advantages and disadvantages of novel siting concepts such as underground containment, offshore siting, and nuclear energy parks are addressed. Other topics include site criteria, risk criteria, and nuclear ship criteria

Nuclear energy and nuclear technology

International Nuclear Information System (INIS)

Luescher, E.

1982-01-01

This book originated in the training courses for teachers of grammar- and secondary schools in Dillingen (Bavaria). The aim of these courses is to become informed about the latest state in one field of physics. The lectures are well-known experts in the respective fields. In the latest study (1980) of the National Academy of Sciences the experts came to the conclusion that without further development nuclear power plants the utilization of too much coal would become necessary and involve irreversible environmental damage (see chapter 6). There are two important obstacles impeding the further extension of nuclear energy. The first problem to be solved is the processing and storage of radioactive waste. This is a more technical task and can be treated in a satisfactory way. The second obstacle is less easy to take as the population has to be convinced that a nuclear power plant can be operated with almost unbelievable safety (see chapter 5) and be shut down safely in the case of incidents. The most promising possibility of controlled nuclear fusion as energy source is still many decades- if feasible at all- away from being performed (see chapter. 7). In the Soviet Union 25% of the electric energy production shall be proceed from nuclear power plants by the year 1990. (orig./GL) [de

Nuclear information services at the National Nuclear Data Center

International Nuclear Information System (INIS)

Burrows, T.W.; Tuli, J.K.

1997-01-01

The National Nuclear Data Center (NNDC) at the Brookhaven National Laboratory has maintained and disseminated data from several numeric and bibliographic data bases for many years. These data bases now cover most of low- and medium-energy nuclear physics and are produced by the NNDC and other groups belonging to various international and national networks. The numeric and bibliographic nuclear data bases maintained by the National Nuclear Data Center and access to these data bases is described. The U.S. Nuclear Data and Reaction Data Networks is also briefly described. (author)