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1

RELATIVISTIC NUCLEAR COLLISIONS: THEORY  

E-Print Network [OSTI]

Effects in Relativistic Nuclear Collisions", Preprint LBL-Pion Interferometry of Nuclear Collisions. 18.1 M.Gyulassy,was supported by the Office of Nuclear Physics of the U.S.

Gyulassy, M.

2010-01-01T23:59:59.000Z

2

Relativistic Nuclear Collisions  

E-Print Network [OSTI]

A comprehensive introduction is given to the field of relativistic nuclear collisions, and the phase diagram of strongly interacting matter. The content of this complex of reviews is shown.

Reinhard Stock

2009-07-29T23:59:59.000Z

3

Constraints on the Path-Length Dependence of Jet Quenching in Nuclear Collisions at RHIC and LHC  

E-Print Network [OSTI]

Recent data on the high-pT pion nuclear modification factor, $R_{AA}(p_T)$, and its elliptic azimuthal asymmetry, $v_2(p_T)$, from RHIC/BNL and LHC/CERN are analyzed in terms of a wide class of jet-energy loss models coupled to different (2+1)d transverse plus Bjorken expanding hydrodynamic fields. We test the consistency of each model by demanding a simultaneous account of the azimuthal, the transverse momentum, and the centrality dependence of the data at both 0.2 and 2.76 ATeV energies. We find a rather broad class of jet-energy independent energy-loss models $dE/dx= \\kappa(T) x^z T^{2+z} \\zeta_q$ that, when coupled to bulk constrained temperature fields T(x,t), can account for the current data at the $\\chi^2energy-loss fluctuations via a convenient scaling factor distributed in a finite range $0energy loss model with a temperature-independent jet-medium coupling as well as a near-$T_c$ dominated, pQCD-inspired energy-loss scenario are shown to be inconsistent with the LHC data, once the parameters are constrained by fitting to RHIC results, we find several new solutions with a temperature-dependent jet-medium coupling. We conclude that the current level of statistical and systematic uncertainties of the measured data does not allow a constraint on the path-length exponent z to a range narrower than [0-2].

Barbara Betz; Miklos Gyulassy

2014-10-17T23:59:59.000Z

4

PROBING DENSE NUCLEAR MATTER VIA NUCLEAR COLLISIONS  

E-Print Network [OSTI]

University of California. LBL-12095 Probing Dense NuclearMatter Nuclear Collisions* v~a H. Stocker, M.Gyulassy and J. Boguta Nuclear Science Division Lawrence

Stocker, H.

2012-01-01T23:59:59.000Z

5

Theoretical interpretation of high-energy nuclear collisions.  

SciTech Connect (OSTI)

Nuclear collisions are interpreted theoretically. The nuclear equation of state is studied in a wide energy range. Subnucleonic degrees of freedom are invoked at high energy densities and at short length-scales. Questions of dynamical collision simulations are investigated. Direct support is provided for experiment in the form of collaborative projects. The major objective of this nuclear theory program is a better understanding of the properties of strongly interacting matter on the nuclear energy scale, as manifested in high-energy heavy-ion collisions.

Fai, G.

1992-06-01T23:59:59.000Z

6

Critical QCD in Nuclear Collisions  

E-Print Network [OSTI]

A detailed study of correlated scalars, produced in collisions of nuclei and associated with the $\\sigma$-field fluctuations, $(\\delta \\sigma)^2= $, at the QCD critical point (critical fluctuations), is performed on the basis of a critical event generator (Critical Monte-Carlo) developed in our previous work. The aim of this analysis is to reveal suitable observables of critical QCD in the multiparticle environment of simulated events and select appropriate signatures of the critical point, associated with new and strong effects in nuclear collisions.

N. G. Antoniou; Y. F. Contoyiannis; F. K. Diakonos; G. Mavromanolakis

2005-05-20T23:59:59.000Z

7

Baryon Fluctuations in High Energy Nuclear Collisions  

E-Print Network [OSTI]

We propose that dramatic changes in the variances and covariance of protons and antiprotons can result if baryons approach chemical equilibrium in nuclear collisions at RHIC. To explore how equilibration alters these fluctuations, we formulate both equilibrium and nonequilibrium hadrochemical descriptions of baryon evolution. Contributions to fluctuations from impact parameter averaging and finite acceptance in nuclear collisions are numerically simulated.

Sean Gavin; Claude Pruneau

1999-07-09T23:59:59.000Z

8

NUCLEAR FLUID DYNAMICS VERSUS INTRANUCLEAR CASCADE--POSSIBLE EVIDENCE FOR COLLECTIVE FLOW IN CENTRAL HIGH ENERGY NUCLEAR COLLISIONS  

E-Print Network [OSTI]

Flow in Central High Energy Nuclear Collisions H. Stockera,theoretical models of high energy nuclear collisions andunder Contract High energy nuclear collisions offer a unique

Stocker, H.

2012-01-01T23:59:59.000Z

9

Partonic EoS in High-Energy Nuclear Collisions at RHIC  

E-Print Network [OSTI]

Partonic EoS in High-Energy Nuclear Collisions at RHIC Nu Xuproperties. In high-energy nuclear collisions, the term ?owthe early stage of high-energy nuclear collision, both the

Xu, Nu

2006-01-01T23:59:59.000Z

10

Memory and correlation effects in nuclear collisions  

SciTech Connect (OSTI)

Relaxation rates are calculated by numerically solving the Kadanoff-Baym equations for an extended system of nuclear matter. The time evolutions of initial nonequilibrium distributions in momentum space, defined by two Fermi spheres, is studied. Comparisons are made with the (semi-) classical method used in BUU, VUU, etc. Danielewicz has found that at a nucleon density of {similar_to}0.3 nucleon/fm{sup 3} and an equilibrated temperature of about 70 MeV, the quantum relaxation rate is smaller than the classical by a factor of about 2. These results are confirmed. The calculations are extended to lower temperatures (energies) and densities and this ratio is found to be essentially unchanged over a wide range although there are deviations from this rule as seen in the text. The quantum evolutions are started either with an uncorrelated or a correlated initial distribution. The latter are obtained with imaginary time stepping. The relaxation time approximation was previously found to be excellent for the classical evolution. It is found to be as good for the quantum evolution. The memory time is in the present calculations found to be less than 5 fm/{ital c} (i.e., {similar_to}1.7{times}10{sup {minus}23} s). One concludes that quantum-mechanical effects have to be incorporated in the models of heavy ion collisions and nuclear dynamics. Not until this is done comprehensively will one be able to readily assess the role of two-nucleon collisions in the equilibration process.

Koehler, H.S. [Physics Department, University of Arizona, Tucson, Arizona 85721 (United States)] [Physics Department, University of Arizona, Tucson, Arizona 85721 (United States)

1995-06-01T23:59:59.000Z

11

Proposal for study of $\\pi^{-}$ nucleur collisions in nuclear emulsion exposed in a pulsed magnetic field  

E-Print Network [OSTI]

Proposal for study of $\\pi^{-}$ nucleur collisions in nuclear emulsion exposed in a pulsed magnetic field

CERN. Geneva. SPS Experiments Committee

1980-01-01T23:59:59.000Z

12

Collective phenomena in non-central nuclear collisions  

SciTech Connect (OSTI)

Recent developments in the field of anisotropic flow in nuclear collision are reviewed. The results from the top AGS energy to the top RHIC energy are discussed with emphasis on techniques, interpretation, and uncertainties in the measurements.

Voloshin, Sergei A.; Poskanzer, Arthur M.; Snellings, Raimond

2008-10-20T23:59:59.000Z

13

Ultra-relativistic nuclear collisions: event shape engineering  

E-Print Network [OSTI]

The evolution of the system created in a high energy nuclear collision is very sensitive to the fluctuations in the initial geometry of the system. In this letter we show how one can utilize these large fluctuations to select events corresponding to a specific initial shape. Such an "event shape engineering" opens many new possibilities in quantitative test of the theory of high energy nuclear collisions and understanding the properties of high density hot QCD matter.

Jurgen Schukraft; Anthony Timmins; Sergei A. Voloshin

2012-08-22T23:59:59.000Z

14

Nuclear molecular configurations in heavy ion collisions  

SciTech Connect (OSTI)

The possibilities of nuclear molecular configurations in symmetric and asymmetric heavy ion collisions are investigated by choosing a proper parametrization for the molecule-like compound state. We treat the nucleus as a rotating liquid drop in terms of the elliptic lemniscatoid parametrization suggested by Royer and Remaud which describes all deformed shapes that occur during the process of fusion of two nuclei, starting from two touching spheres to a single one with the intermediate formation of a deep neck. Only one parameter ({ital s} for the symmetric and {ital s}{sub 1} for the conditional asymmetric case) is needed to define all the shapes encountered in the process. The shape has a neck as long as {ital s} or {ital s}{sub 1} is less than 1/ {radical}2 . In this parametrization, analytical expressions can be obtained for volume, surface, and moment of inertia while the Coulomb energy has to be evaluated numerically. The total energy of the system is calculated as a function of the parameter {ital s} or {ital s}{sub 1}, for various spins and if the stable shape corresponding to minimum energy is one with a neck, then it is concluded that the molecular configuration is possible. Our model yields results which are in good agreement with the experimental findings.

Shanmugam, G.; Padmini, M.D. (Department of Physics, Presidency College, Madras 600005, India (IN))

1989-09-01T23:59:59.000Z

15

Pion production in relativistic collisions of nuclear drops  

SciTech Connect (OSTI)

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.

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

1988-09-01T23:59:59.000Z

16

Anisotropic Flow and Jet Quenching in Relativistic Nuclear Collisions  

E-Print Network [OSTI]

The exploration of the strong-interaction matter under extreme conditions is one of the main goals of relativistic heavy-ion collisions. We provide some of the main results on the novel properties of quark-gluon plasma, with particular focus given to the strong collectivity and the color opaqueness exhibited by such hot and dense matter produced in high-energy nuclear collisions at RHIC and the LHC.

Qin, Guang-You

2015-01-01T23:59:59.000Z

17

Anisotropic Flow and Jet Quenching in Relativistic Nuclear Collisions  

E-Print Network [OSTI]

The exploration of the strong-interaction matter under extreme conditions is one of the main goals of relativistic heavy-ion collisions. We provide some of the main results on the novel properties of quark-gluon plasma, with particular focus given to the strong collectivity and the color opaqueness exhibited by such hot and dense matter produced in high-energy nuclear collisions at RHIC and the LHC.

Guang-You Qin

2015-02-09T23:59:59.000Z

18

Quantum theory of nonequilibrium processes II. Application to nuclear collisions  

SciTech Connect (OSTI)

In the high-energy (E/sub lab/> or =200 MeV/nucl) heavy ion-collisions, the quantum uncertainty of nucleon energies, given by the collision frequency, is of the order of (50-100) MeV. At hundreds MeV/nucl beam energies, the uncertainty is comparable with nucleon energies in the equal ion-velocity frame, indicating a quantum character of the dynamics. The quantum dynamics of a collision process is examined using nonequilibrium Green's function methods. Numerical calculations of collisions in an interpenetrating nuclear matter model, at the energy E/sub lab/ = 400 MeV/nucl, are performed. Comparison of the quantum dynamics, with the classical Markovian dynamics from the Boltzmann equation, reveals effects of the ill-defined nucleon energies in the nucleon momentum distribution. It is shown that the quantum dynamics proceeds twice as slow as Boltzmann dynamics, but the off-shell kinematics compensates for this somewhat.

Danielewicz, P.

1984-02-01T23:59:59.000Z

19

Hadron Production at Forward Rapidity in Nuclear Collisions at RHIC  

E-Print Network [OSTI]

. The net-proton yield in the same system is compared with that from AGS and SPS energies to study the high collisions, hadron production, net-proton, nuclear mod- ification factor, Cronin effect, jet-quenching 1 of fluid dynamics in their interpretation. Hydrodynamics properties of the expanding matter created

20

Physics of Nuclear Collisions at High Energy  

SciTech Connect (OSTI)

A wide range of problems has been investigated in the research program during the period of this grant. Although the major effort has been in the subject of heavy-ion collisions, we have also studied problems in biological and other physical systems. The method of analysis used in reducing complex data in multiparticle production to simple descriptions can also be applied to the study of complex systems of very different nature. Phase transition is an important phenomenon in many areas of physics, and for heavy-ion collisions we study the fluctuations of multiplicities at the critical point. Human brain activities as revealed in EEG also involve fluctuations in time series, and we have found that our experience enables us to find the appropriate quantification of the fluctuations in ways that can differentiate stroke and normal subjects. The main topic that characterizes the research at Oregon in heavy-ion collisions is the recombination model for the treatment of the hadronization process. We have avoided the hydrodynamical model partly because there is already a large community engaged in it, but more significantly we have found the assumption of rapid thermalization unconvincing. Recent results in studying LHC physics lead us to provide more evidence that shower partons are very important even at low p_T, but are ignored by hydro. It is not easy to work in an environment where the conventional wisdom regards our approach as being incorrect because it does not adhere to the standard paradigm. But that is just what a vibrant research community needs: unconventional approach may find evidences that can challenge the orthodoxy. An example is the usual belief that elliptic flow in fluid dynamics gives rise to azimuthal anisotropy. We claim that it is only sufficient but not necessary. With more data from LHC and more independent thinkers working on the subject what is sufficient as a theory may turn out to be incorrect in reality. Another area of investigation that has long been associated with this PI is the study of quark-hadron phase transition in heavy-ion collisions. Finally, at LHC enough particles are produced to make feasible the investigation of intermittency and erraticity indices that we have proposed as signatures of that phase transition.

Hwa, Rudolph C.

2012-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Nuclear effects on J/? production in proton-nucleus collisions  

E-Print Network [OSTI]

The study of nuclear effects for J/{\\psi} production in proton-nucleus collisions is crucial for a correct interpretation of the J/{\\psi} suppression patterns experimentally observed in heavy-ion collisions. By means of three representative sets of nuclear parton distribution, the energy loss effect in the initial state and the nuclear absorption effect in the final state are taken into account in the uniform framework of the Glauber model. A leading order phenomenological analysis is performed on J/{\\psi} production cross-section ratios RW/Be(xF) for the E866 experimental data. The J/{\\psi} suppression is investigated quantitatively due to the different nuclear effects. It is shown that the energy loss effect with resulting in the suppression on RW/Be(xF) is more important than the nuclear effects on parton distributions in high xF region. The E866 data in the small xF keep out the nuclear gluon distribution with a large anti-shadowing effect. However, the new HERA-B measurement is not in support of the anti-shadowing effect in the nuclear gluon distribution. It is found that the J/{\\psi}-nucleon inelastic cross section {\\sigma} J/{\\psi} abs depends on the kinematical variable xF, and increases as xF in the region xF > 0.2. 1 Introduction

Chun-Gui Duan; Jian-Chao Xu; Li-Hua Song

2011-09-25T23:59:59.000Z

22

Nuclear absorption and $J/?$ suppression in Pb+Pb collisions  

E-Print Network [OSTI]

We have analyzed the NA58 data on $J/\\psi$ suppression in Pb+Pb collisions. $J/\\psi$ production is assumed to be a two step process, (i) formation of $c\\bar{c}$ pair, which is accurately calculable in QCD and (ii) formation of $J/\\psi$ meson from the $c\\bar{c}$ pair, which can be conveniently parameterized. In a pA/AA collision, a $c\\bar{c}$ pair gain relative square momentum as it passes through the nuclear medium and some of the $c\\bar{c}$ pairs can gain enough momentum to cross the threshold to become an open charm meson, leading to suppression in pA/AA collisions. A new prescription is proposed for the gain in momentum square, consistent with Krammer process. The model without any free parameter could explain the $E_T$ dependence of $J/\\psi$ over Drell-Yan ratio.

A. K. Chaudhuri

2002-03-18T23:59:59.000Z

23

Nuclear Fusion via Triple Collisions in Solar Plasma  

E-Print Network [OSTI]

We consider several nuclear fusion reactions that take place at the center of the sun, which are omitted in the standard pp-chain model. More specifically the reaction rates of the nonradiative production of ^3He, ^7Be, and ^8B nuclei in triple collisions involving electrons are estimated within the framework of the adiabatic approximation. These rates are compared with those of the corresponding binary fusion reactions.

V. B. Belyaev; D. E. Monakhov; N. Shevchenko; S. A. Sofianos; S. A. Rakityansky; M. Braun; L. L. Howell; W. Sandhas

1997-09-09T23:59:59.000Z

24

Signatures of new phenomena in ultrarelativistic nuclear collisions  

SciTech Connect (OSTI)

Three classes of observables are discussed which may shed light on the properties of the quark-gluon plasma formed in ultrarelativistic nuclear collisions. They are: (1) thermometers: the penetrating probes ..mu../sup +/..mu../sup -/, ..gamma.., c, (2) barometers: transverse flow via

, and (3) seismometers: fluctuations of dN/dy and dE perpendicular/dy. The need for reliable estimates of the background due to the non-equilibrium processes is emphasized. 49 references.

Gyulassy, M.

1983-11-01T23:59:59.000Z

25

JETS OF NUCLEAR MATTER FROM HIGH ENERGY HEAVY ION COLLISIONS  

SciTech Connect (OSTI)

The nuclear fluid dynamical model with final thermal breakup is used to study the reactions {sup 20}Ne + {sup 238}U and {sup 40} Ar + {sup 40}Ca at E{sub LAB}=390 MeV/n. Calculated double differential cross sections d{sup 2}{sigma}/d{Omega}dE are in agreement with recent experimental data. It is shown that azimuthally dependent triple differential cross sections d{sup 3}{sigma}/dEd cos{theta}d{phi} yield considerably deeper insight into the collision process and allow for snapshots of the reactions. Strongly correlated jets of nuclear matter are predicted.

Stocker, H.; Csernai, L.P.; Graebner, G.; Buchwald, G.; Kruse, H.; Cusson, R.Y.; Maruhn, J.A.; Greiner, W.

1980-11-01T23:59:59.000Z

26

Dynamics of heavy flavor quarks in high energy nuclear collisions  

E-Print Network [OSTI]

A general overview on the role of heavy quarks as probes of the medium formed in high energy nuclear collisions is presented. Experimental data compared to model calculations at low and moderate pT are exploited to extract information on the transport coefficients of the medium, on possible modifications of heavy flavor hadronization in a hot environment and to provide quantitative answers to the issue of kinetic (and chemical, at conceivable future experimental facilities) thermalization of charm. Finally, the role of heavy flavor at high pT as a tool to study the mass and color-charge dependence the jet quenching is also analyzed.

Andrea Beraudo

2014-07-22T23:59:59.000Z

27

DDbar Correlations probing Thermalization in High-Energy Nuclear Collisions  

E-Print Network [OSTI]

We propose to measure azimuthal correlations of heavy-flavor hadrons to address the status of thermalization at the partonic stage of light quarks and gluons in high-energy nuclear collisions. In particular, we show that hadronic interactions at the late stage cannot significantly disturb the initial back-to-back azimuthal correlations of DDbar pairs. Thus, a decrease or the complete absence of these initial correlations does indicate frequent interactions of heavy-flavor quarks and also light partons in the partonic stage, which are essential for the early thermalization of light partons.

K. Schweda; X. Zhu; M. Bleicher; S. L. Huang; H. Stoecker; N. Xu; P. Zhuang

2006-10-30T23:59:59.000Z

28

JETS OF NUCLEAR MATTER FROM HIGH ENERGY HEAVY ION COLLISIONS  

SciTech Connect (OSTI)

The nuclear fluid dynamical model with final thermal breakup is used to study the reactions {sup 20}Ne + {sup 238}U and {sup 40}Ar + {sup 40}Ca at E{sub LAB} = 390 MeV/n. The calculated double differential cross sections d{sup 2}{sigma}/d{Omega}dE are in agreement with recent experimental data. However, it is shown that the azimuthal dependence of the triple differential distributions d{sup 3}{sigma}/dEdcos{theta}d{phi}, to be obtained from 4{pi} exclusive experiments with single event analysis, can yield considerably deeper insight into the collision process and allow for snapshots of the reactions. Strongly correlated jets of nuclear matter are predicted.

Stocker, H.; Csernai, L.P.; Graebner, G.; Buchwald, G.; Kruse, H.; Cusson, R.Y.; Maruhn, J.A.; Greiner, W.

1981-02-01T23:59:59.000Z

29

A study of nuclear stopping in central symmetric nuclear collisions at intermediate energies  

E-Print Network [OSTI]

Nuclear stopping has been investigated in central symmetric nuclear collisions at intermediate energies. Firstly, it is found that the isotropy ratio, Riso, reaches a minimum near the Fermi energy and saturates or slowly increases depending on the mass of the system as the beam energy increases. An approximate scaling based on the size of the system is found above the Fermi energy suggesting the increasing role of in-medium nucleon-nucleon collisions. Secondly, the charge density distributions in velocity space, dZ/dvk and dZ/dv?, reveal a strong memory of the entrance channel and, as such, a sizeable nuclear transparency in the intermediate energy range. Lastly, it is shown that the width of the transverse velocity distribution is proportional to the beam velocity.

C. Escano-Rodriguez; D. Durand; A. Chbihi; J. D. Frankland; the INDRA Collaboration

2005-03-14T23:59:59.000Z

30

Nuclear Equation of State: Picture from Medium Energy Heavy Ion Collisions  

E-Print Network [OSTI]

Characteristics of the nuclear equation of state (EOS) and its importance, in particular for astrophysics, are discussed. Selected observables in nuclear collisions are sensitive to the EOS and can be used to constrain it. For central collisions, these include collective flow asymmetries, subthreshold kaon yields and isospin diffusion. Comparisons between the data and transport theory suggest an energy per nucleon that rises relatively slowly with density for symmetric matter and symmetry energy that rises relatively quickly around the normal nuclear density.

P. Danielewicz

2005-12-02T23:59:59.000Z

31

Nuclear like effects in proton-proton collisions at high energy  

E-Print Network [OSTI]

We show that several effects considered nuclear effects are not nuclear in the sense that they do not only occur in nucleus-nucleus and hadron-nucleus collisions but, as well, they are present in hadron-hadron (proton-proton) collisions. The matter creation mechanism in hh, hA and AA collisions is always the same. The pT suppression of particles produced in large multiplicity events compared to low multiplicity events, the elliptic flow and the Cronin effect are predicted to occur in pp collisions at LHC energies as a consequence of the obtained high density partonic medium.

L. Cunqueiro; J. Dias de Deus; C. Pajares

2009-09-17T23:59:59.000Z

32

$J/?$ production in Au+Au collisions at RHIC and the nuclear absorption  

E-Print Network [OSTI]

It is shown that a QCD based nuclear absorption model, with few parameters fixed to reproduce experimental $J/\\psi$ yield in 200 GeV pp/pA and 450 GeV pA collisions can explain the preliminary PHENIX data on the centrality dependence of $J/\\psi$ suppression in Cu+Cu collisions at RHIC energy, $\\sqrt{s_{NN}}$=200 GeV. However, the model does not give satisfactory description to the preliminary PHENIX data on the centrality dependence of $J/\\psi$ suppression in Au+Au collisions. The analysis suggest that in Au+Au collisions, $J/\\psi$ are suppressed in a medium unlike the medium produced in SPS energy nuclear collisions or in RHIC energy Cu+Cu collisions.

A. K. Chaudhuri

2006-11-09T23:59:59.000Z

33

A new explanation to the cold nuclear matter effects in heavy ion collisions  

E-Print Network [OSTI]

The J/Psi cross section ratios of p-A/p-p under different collision energy is calculated with cold nuclear matter effects redefined in this paper. The advantage of these new definitions is that all cold nuclear matter effects have clear physical origins.The radios are compared with the corresponding experiment data and that calculated with classic nuclear effects. The ratios calculated with new definitions can reproduce almost all existing J/Psi measurements in p-A collisions more accuratly than that calculated with classic nuclear effects. Hence, this paper presents a new approach to explain cold nuclear effects in the hardproduction of quarkonium.

Zhi-Feng Liu

2014-11-23T23:59:59.000Z

34

Magnetic Field Effect on Charmonium Production in High Energy Nuclear Collisions  

E-Print Network [OSTI]

It is important to understand the strong external magnetic field generated at the very beginning of high energy nuclear collisions. We study the effect of the magnetic field on the charmonium yield and anisotropic distribution in Pb+Pb collisions at the LHC energy. The time dependent Schr\\"odinger equation is employed to describe the motion of $c\\bar{c}$ pairs. We compare our model prediction of non- collective anisotropic parameter $v_2$ of $J/\\psi$s with CMS data at high transverse momentum. This is the first attempt to measure the magnetic field in high energy nuclear collisions.

Guo, Xingyu; Xu, Nu; Xu, Zhe; Zhuang, Pengfei

2015-01-01T23:59:59.000Z

35

Minijet transverse energy production in the next-to-leading order in hadron and nuclear collisions  

E-Print Network [OSTI]

The transverse energy flow generated by minijets in hadron and nuclear collisions into a given rapidity window in the central region is calculated in the next-to-leading (NLO) order in QCD at RHIC and LHC energies. The NLO transverse energy production in pp collisions cross sections are larger than the LO ones by the factors of K_{RHIC} ~ 1.9 and K_{LHC} ~ 2.1 at RHIC and LHC energies correspondingly. These results were then used to calculate transverse energy spectrum in nuclear collisions in a Glauber geometrical model. We show that accounting for NLO corrections in the elementary pp collisions leads to a substantial broadening of the E_{perp} distribution for the nuclear ones, while its form remains practically unchanged.

A. V. Leonidov; D. M. Ostrovsky

1998-11-23T23:59:59.000Z

36

Minijet transverse energy production in the next-to-leading order in hadron and nuclear collisions  

E-Print Network [OSTI]

The transverse energy flow generated by minijets in hadron and nuclear collisions into a given rapidity window in the central region is calculated in the next-to-leading (NLO) order in QCD at RHIC and LHC energies. The NLO transverse energy production in pp collisions cross sections are larger than the LO ones by the factors of $K_{RHIC} \\sim 1.9$ and $K_{LHC} \\sim 2.1$ at RHIC and LHC energies correspondingly. These results were then used to calculate transverse energy spectrum in nuclear collisions in a Glauber geometrical model. We show that accounting for NLO corrections in the elementary pp collisions leads to a substantial broadening of the $E_{\\perp}$ distribution for the nuclear ones, while its form remains practically unchanged.

Leonidov, A V

1998-01-01T23:59:59.000Z

37

Study of Cold Nuclear Matter Effects on Heavy Quarkonia in Proton-Lead Collisions at LHCb  

E-Print Network [OSTI]

Proton-nucleus ($p\\rm{A}$) collisions play an important role in high energy nuclear physics as they allow to study nuclear matter effects and the parton distribution functions in the nuclear environment (nPDF). The quantum chromodynamics (QCD) phase transition from hadron gas to the the quark-gluon plasma (QGP) is not expected to occur in a $p\\rm{A}$ collision due to its limited space-time size. Therefore, the $p\\rm{A}$ collisions provide an ideal platform to study cold nuclear matter (CNM) effects, which are also known as normal nuclear matter effects. The measurements of the productions and correlations of the final-state particles in $p\\rm{A}$ collisions serve the purpose to test various theoretical models for CNM effects, to constrain the benchmarking nPDFs, and thus provide a baseline to understand and interpret the QGP created in ultra-relativistic heavy-ion collisions. Heavy quarkonia (including charmonia and bottomonia), which are produced at the early stage of heavy-ion collisions, are considered goo...

Jing, Fanfan; Yang, Zhenwei; Schmidt, Burkhard

38

Effective-energy budget in multiparticle production in nuclear collisions  

E-Print Network [OSTI]

The dependencies of charged particle pseudorapidity density and transverse energy pseudorapidity density at midrapidity on the collision energy and on the number of nucleon participants, or centrality, measured in nucleus-nucleus collisions are studied in the energy range spanning a few GeV to a few TeV per nucleon. The model in which the multiparticle production is driven by the dissipating effective energy of participants is introduced. The model is based on the earlier proposed approach, combining the constituent quark picture together with Landau relativistic hydrodynamics shown to interrelate the measurements from different types of collisions. Within this model, the dependence on the number of participants in heavy-ion collisions are found to be well described in terms of the effective energy defined as a centrality-dependent fraction of the collision energy. For both variables under study, the effective energy approach reveals a similarity in the energy dependence obtained for the most central collisions and centrality data in the entire available energy range. Predictions are made for the investigated dependencies for the forthcoming higher energy measurements in heavy-ion collisions at the LHC.

Aditya Nath Mishra; Raghunath Sahoo; Edward K. G. Sarkisyan; Alexander S. Sakharov

2014-11-24T23:59:59.000Z

39

Stress tensor and bulk viscosity in relativistic nuclear collisions  

E-Print Network [OSTI]

We discuss the influence of different initial conditions for the stress tensor and the effect of bulk viscosity on the expansion and cooling of the fireball created in relativistic heavy ion collisions. In particular, we explore the evolution...however, it does not significantly increase the entropy produced....

Fries, Rainer J.; Mueller, Berndt; Schaefer, Andreas.

2008-01-01T23:59:59.000Z

40

Nuclear modification and azimuthal anisotropy of D mesons produced in relativistic heavy ion collision  

E-Print Network [OSTI]

In this paper we present a phenomenological treatment of charm quark energy loss before fragmenting into D mesons and calculate nuclear modification factor, '$R_{AA}$' and azimuthal anisotropy, '$v_2$' of D mesons for lead on lead collision at LHC energy of $\\sqrt{s}$=2.76 A TeV.

Younus, Mohammed

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Decoherence and entropy production in relativistic nuclear collisions  

E-Print Network [OSTI]

, the anisotropic collective transverse flow may be generated, in part, by interactions of minijets with the bulk medium [14] or by anisotropies in the initial gluon field [15]. Hydrodynamic calculations with viscous corrections describing small deviations from... then extract information on the original wave function. In heavy-ion collisions each Lorentz contracted ion acts like such a foil for the other. That the loss of information due to decoherence can generate a rapid increase in entropy in early phases...

Fries, Rainer J.; Mueller, Berndt; Schaefer, Andreas.

2009-01-01T23:59:59.000Z

42

J/Psi suppression in ultrarelativistic nuclear collisions  

E-Print Network [OSTI]

circles for Au1Au col- lisions and open circles for S1S collisions. The solid lines are polynomial fits to the above results using the form rc(t)5a01a1t1a2t21a3t3 for tmin,t,tmax , with rc(t) 5rc(tmin) for t,tmin and rc(t)50 for t.tmax . For the par...

Zhang, B.; Ko, Che Ming; Li, Ba; Lin, ZW; Sa, BW.

2000-01-01T23:59:59.000Z

43

Symmetry energy for fragmentation in dynamical nuclear collisions  

SciTech Connect (OSTI)

We extract values for the free symmetry energy as a function of the fragment size (the proton number Z) from antisymmetrized molecular dynamics calculations of calcium collisions. Simple statistical physics describe well the distribution of hot nuclei at breakup, provided the surface symmetry term in the free energy is much smaller at high excitation than in ground state nuclei. This result may reflect the condition of low density and finite temperature when these systems disassemble.

Ono, Akira [Department of Physics, Tohoku University, Sendai 980-8578 (Japan); Danielewicz, P.; Lynch, W.G.; Tsang, M.B. [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States); Friedman, W.A. [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States)

2004-10-01T23:59:59.000Z

44

Low Density Nuclear Matter in Heavy Ion Collisions  

E-Print Network [OSTI]

2 ,a a = 93.15 MeV/c 2 , and the pairing term, B, is 0 MeV/c 2 for odd-even or even-odd nuclei, -11.2 MeV/c 2 for even-even nuclei and +11.2 MeV/c 2 for odd-odd nuclei [24, 25, 26, 27, 28]. A classical result is shown in the Fig. 2. 6 Fig. 2. Binding... dissertation project possible. vii TABLE OF CONTENTS CHAPTER Page I INTRODUCTION .......................... 1 A. General Picture of Heavy Ion Collisons ........... 1 B. Transport Models to Simulate Heavy Ion Collisions .... 2 C...

Qin, Lijun

2010-01-14T23:59:59.000Z

45

A study of vorticity formation in high energy nuclear collisions  

E-Print Network [OSTI]

We present a quantitative study of vorticity formation in peripheral ultrarelativistic heavy ion collisions at sqrt(s_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 and discuss different definitions of vorticity which are relevant in relativistic hydrodynamics. After demonstrating the excellent capabilities of our code, 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 eta/s=0.16 fixed, a vorticity of up to 0.05 c/fm can develop at freezeout. The ensuing polarization of Lambda baryons is at most of the order of 1% 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.

Becattini, F; Rolando, V; Beraudo, A; Del Zanna, L; De Pace, A; Nardi, M; Pagliara, G; Chandra, V

2015-01-01T23:59:59.000Z

46

On the balance energy and nuclear dynamics in peripheral heavy-ion collisions  

E-Print Network [OSTI]

We present here the system size dependence of balance energy for semi-central and peripheral collisions using quantum molecular dynamics model. For this study, the reactions of $Ne^{20}+Ne^{20}$, $Ca^{40}+Ca^{40}$, $Ni^{58}+Ni^{58}$, $Nb^{93}+Nb^{93}$, $Xe^{131}+Xe^{131}$ and $Au^{197}+Au^{197}$ are simulated at different incident energies and impact parameters. A hard equation of state along with nucleon-nucleon cross-sections between 40 - 55 mb explains the data nicely. Interestingly, balance energy follows a power law $\\propto{A^{\\tau}}$ for the mass dependence at all colliding geometries. The power factor $\\tau$ is close to -1/3 in central collisions whereas it is -2/3 for peripheral collisions suggesting stronger system size dependence at peripheral geometries. This also suggests that in the absence of momentum dependent interactions, Coulomb's interaction plays an exceedingly significant role. These results are further analyzed for nuclear dynamics at the balance point.

Rajiv Chugh; Rajeev K. Puri

2010-03-16T23:59:59.000Z

47

Nuclear absorption and anomalous $J/?$ suppression in Pb+Pb collisions  

E-Print Network [OSTI]

We discuss $J/\\psi$ suppression in a QCD based nuclear absorption model. Centrality dependence of $J/\\psi$ suppression in S+U and in Pb+Pb collisions are explained in the model. However, the model fails to explain the centrality dependence of $\\psi\\prime$ suppression. $\\psi\\prime$ suppression in S+U or in Pb+Pb collisions require additional suppression. Additional suppression of $\\psi\\prime$, due to hadronic comovers or due to QGP formation could not be distinguished in Pb+Pb collisions. We then show that the centrality dependence of the ratio, $\\psi\\prime$ over $J/\\psi$, could possibly distinguish two scenario (e.g. QGP or hadronic comover) at RHIC energy.

A. K. Chaudhuri

2003-07-31T23:59:59.000Z

48

The effect of partonic wind on charm quark correlations in high-energy nuclear collisions  

E-Print Network [OSTI]

In high-energy collisions, massive heavy quarks are produced back-to-back initially and they are sensitive to early dynamical conditions. The strong collective partonic wind from the fast expanding quark-gluon plasma created in high-energy nuclear collisions modifies the correlation pattern significantly. As a result, the angular correlation function for D$\\bar{\\rm D}$ pairs is suppressed at the angle $\\Delta\\phi=\\pi$. While the hot and dense medium in collisions at RHIC ($\\sqrt{s_{NN}}=200$ GeV) can only smear the initial back-to-back D$\\bar {\\rm D}$ correlation, a clear and strong near side D$\\bar{\\rm D}$ correlation is expected at LHC ($\\sqrt{s_{NN}}=5500$ GeV).

X. Zhu; N. Xu; P. Zhuang

2007-09-03T23:59:59.000Z

49

Effects of nuclear absorption on the antiLambda/antiproton ratio in relativistic heavy ion collisions  

E-Print Network [OSTI]

An enhanced antiLambda/antiproton ratio in heavy-ion relative to p+p collisions has been proposed as one of the signatures for the Quark-Gluon Plasma (QGP) formation. A significantly large (antiLambda+antiSigma0+1.1*antiSigma-)/antiproton ratio of 3.5 has been observed in the mid-rapidity and low transverse momentum region in central Au+Au collisions at the nucleon-nucleon center-of-mass energy of 4.9 GeV at the Alternating Gradient Synchrotron (AGS). This is an order of magnitude larger than the values in peripheral Au+Au collisions and p+p collisions at the corresponding energy. By using the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) transport model, we demonstrate that the observed large ratio can be explained by strong absorption of antiprotons (~99.9%) and antiLambdas (~99%) in dense nuclear matter created in central collisions. We find within the model that the initial antiLambda/antiproton ratio, mainly from string fragmentation, does not depend on the collision centrality, and is consistent with that observed in p+p collisions. This suggests that the observed large (antiLambda+antiSigma0+1.1*antiSigma-)/antiproton ratio at the AGS does not necessarily imply the formation of the QGP. We further study the excitation function of the ratio in UrQMD, which may help in the search and study of the QGP.

Fuqiang Wang; Marlene Nahrgang; Marcus Bleicher

2012-06-30T23:59:59.000Z

50

Forward Lambda Production and Nuclear Stopping Power in d+Au Collisions at RHIC  

E-Print Network [OSTI]

Using the forward time projection chambers of STAR we measure the centrality dependent Lambda and Anti-Lambda yields in d+Au collisions at \\sqrt{s_{NN} = 200 GeV at forward and backward rapidities. The contributions of different processes to particle production and baryon transport are probed exploiting the inherent asymmetry of the d+Au system. While the d side appears to be dominated by multiple independent nucleon-nucleon collisions, nuclear effects contribute significantly on the Au side. Using the constraint of baryon number conservation, the rapidity loss of baryons in the incoming deuteron can be estimated as a function of centrality. This is compared to a model and to similar measurements in Au+Au, which gives insights into the nuclear stopping power at relativistic energies.

Frank Simon; for the STAR collaboration

2006-02-09T23:59:59.000Z

51

Thermal dileptons in high-energy nuclear collisions  

E-Print Network [OSTI]

Clear signs of excess dileptons above the known sources were found at the SPS since long. However, a real clarification of these observations was only recently achieved by NA60, measuring dimuons with unprecedented precision in 158A GeV In-In collisions. The excess mass spectrum in the region M rho -> mu+mu- annihilation. The associated rho spectral function shows a strong broadening, but essentially no shift in mass. In the region M>1 GeV, the excess is found to be prompt, not due to enhanced charm production. The inverse slope parameter Teff associated with the transverse momentum spectra rises with mass up to the rho, followed by a sudden decline above. While the initial rise, coupled to a hierarchy in hadron freeze-out, points to radial flow of a hadronic decay source, the decline above signals a transition to a low-flow source, presumably of partonic origin. The mass spectra show the steep rise towards low masses characteristic for Planck-like radiation. The polarization of the excess referred to the Collins Soper frame is found to be isotropic. All observations are consistent with a global interpretation of the excess as thermal radiation. We conclude with a short discussion of a possible link to direct photons.

Sanja Damjanovic

2008-12-16T23:59:59.000Z

52

Nuclear k_T in d+Au Collisions from Multiparticle Jet Reconstruction at STAR  

E-Print Network [OSTI]

This paper presents the most recent nuclear k_T measurements from STAR derived from multiparticle jet reconstruction of d+Au and p+p collisions at sqrt(s)=200 GeV. Since jets reconstructed from multiple particles are relatively free of fragmentation biases, nuclear k_T can be measured with greater certainty in this way than with traditional di-hadron correlations. Multi-particle jet reconstruction can also be used for a direct measurement of the fragmentation function.

Thomas Henry

2005-11-01T23:59:59.000Z

53

Cold nuclear matter effects on the color singlet J/psi production in d-Au collisions at RHIC  

E-Print Network [OSTI]

We use a Modified DKLMT model (called M-DKLMT model) to study the cold nuclear matter (CNM) effects on the color singlet J/psi production in dAu collisions at RHIC. The cold nuclear effect of dipole-nucleus interactions has been investigated by introducing a nuclear geometric effect function f({\\xi}) to study the nuclear geometry distribution effect in relativistic heavy-ion collisions. The dependencies of nuclear modification factors (RdA) on rapidity and centrality are studied and compared to experimental data. It is found that the M-DKLMT model can well describe the experimental results at both forward- and mid-rapidity regions in dAu collisions at RHIC.

Zefang Jiang; Shengqin Feng; Zhongbao Yin; Yafei Shi; Xianbao Yuan

2014-11-13T23:59:59.000Z

54

Streamer chamber study of intermediate-energy nuclear collisions with CCD cameras  

SciTech Connect (OSTI)

A system of three charge-coupled device (CCD) cameras has been designed and built to record nuclear collisions in a streamer chamber. This technical development significantly enhances the usefulness of streamer chambers as large solid angle ({approx}4{pi} sr) detectors for exclusive measurements in nuclear physics. The system has been used in an experiment designed to study nearly-central collisions of Nb + Nb at 100 and 180 MeV/nucleon. Computer codes have been developed that significantly reduce the amount of operator intervention in the data analysis. One of the most interesting predictions of fluid-dynamical models and VUU calculations for heavy-ion collisions is the sideward emission of nuclear matter, due to the high compression crated during the collision (Stoe 80, Mol 85). The transverse-momentum flow analysis introduced by Danielewicz and Odyniec (Dan 85) allows to calculate the amount of sideward momentum carried by the emitted fragments, while minimizing the distortions caused by finite-multiplicity effects. This momentum flow analysis has been performed on our 180 MeV/nucleon data. The slope of the mean transverse momentum per nucleon vs. rapidity curve at mid-rapidity, or flow, was found to be 47.0 {plus minus} 11.3 MeV/c/nucleon. In order to compare our results to those obtained from other experiments, scale-invariant transverse momentum, p{sup x}, and rapidity, y, have been introduced (Bal 84). The p{sup x} vs. y curve extracted from our data has been compared with the curves obtained for various systems in streamer chamber plus photographic film (Dan 85, Ren 84) and plastic ball experiments (Dos 85), and the shapes have been found to be very similar. The scale-invariant flow, F, for 180 MeV/nucleon Nb + Nb is 0.16 {plus minus} 0.04.

Angius, S.P.

1987-01-01T23:59:59.000Z

55

Nuclear absorption and anomalous J/psi suppression in Pb+Pb collisions  

E-Print Network [OSTI]

We have studied the J/psi suppression in 158 GeV/c Pb+Pb collisions at CERN SPS. J/psi production is assumed to be a two step process, (i) formation of c bar{c} pair, which is accurately calculable in QCD and (ii) formation of J/psi meson from the c bar{c} pair, which can be conveniently parameterized. In a pA/AA collision, as the c bar{c} pair pass through the nuclear medium, it gains relative square momentum. As a result, some of the c bar{c} pairs can gain enough momentum to cross the threshold to become open charm meson, leading to suppression in pA/AA collisions. The model without any free parameter could describe the of NA50 data on centrality dependence of the ratio's; J/psi over Drell-Yan, J/psi over minimum bias and also the Drell-Yan over minimum bias. The model was used to predict J/psi suppression at RHIC energy. At RHIC energy, hard processes may be important. With hard processes included, J/psi's are strongly suppressed, in agreement with other model calculations. We also show that centrality dependence of J/psi over minimum bias ratio can be used to determine the fraction of hard processes in the collision.

A. K. Chaudhuri

2002-07-29T23:59:59.000Z

56

Evidence for radial flow of thermal dileptons in high-energy nuclear collisions  

E-Print Network [OSTI]

The NA60 experiment at the CERN SPS has studied low-mass dimuon production in 158 AGeV In-In collisions. An excess of pairs above the known meson decays has been reported before. We now present precision results on the associated transverse momentum spectra. The slope parameter Teff extracted from the spectra rises with dimuon mass up to the rho, followed by a sudden decline above. While the initial rise is consistent with the expectations for radial flow of a hadronic decay source, the decline signals a transition to an emission source with much smaller flow. This may well represent the first direct evidence for thermal radiation of partonic origin in nuclear collisions.

NA60 Collaboration; R. Arnaldi

2007-11-12T23:59:59.000Z

57

Thermal hard-photons probing multifragmentation in nuclear collisions around the Fermi energy  

E-Print Network [OSTI]

Hard-photon (E$_{\\gamma} >$ 30 MeV) emission issuing from proton-neutron bremsstrahlung collisions is investigated in four different heavy-ion reactions at intermediate bombarding energies ($^{36}$Ar+$^{197}$Au, $^{107}$Ag, $^{58}$Ni, $^{12}$C at 60{\\it A} MeV) coupling the TAPS photon spectrometer with two charged-particle multidetectors covering more than 80% of the solid angle. The hard-photon spectra of the three heavier targets result from the combination of two distinct exponential distributions with different slope parameters, a result which deviates from the behaviour expected for hard-photon production just in first-chance proton-neutron collisions. The thermal origin of the steeper bremsstrahlung component is confirmed by the characteristics of its slope and angular distribution. Such thermal hard-photons convey undisturbed information of the thermodynamical state of hot and excited nuclear systems undergoing multifragmentation.

D. G. d'Enterria; G. Martínez

2000-07-06T23:59:59.000Z

58

Nuclear absorption of Charmoniums in pA and AA collisions  

E-Print Network [OSTI]

We have analysed the latest NA50 data on $J/\\psi$ production in pA and AA collisions. The $J/\\psi$ production is assumed to be a two step process, (i) formation of $c\\bar{c}$ pairs, perturbatively calculable, and (ii) formation of $J/\\psi$ from the pair, a non-perturbative process, which is conviniently parametrized. In a nuclear medium, as the $c\\bar{c}$ pair passes through the nuclear medium, it gain relative square momentum and some of the pairs can gain enough square momentum to cross the threshold for open charm meson, leading to suppression in nuclear medium. Few parameters of the model were fixed from the latest high statistics NA50 pA and NA38 SU total $J/\\psi$ cross sectional data. The model then reproduces the centrality dependence of $J/\\psi$ over Drell-Yan ration in 200 GeV/c S+U and 158 GeV/c Pb+Pb collisions. We also discuss the centrality dependence of $J/\\psi$ suppression at RHIC energy.

A. K. Chaudhuri

2003-05-19T23:59:59.000Z

59

Forward Lambda Production and Nuclear Stopping Power in d + Au Collisions at sqrt(s_NN) = 200 GeV  

E-Print Network [OSTI]

We report the measurement of Lamda and Anti-Lamda yields and inverse slope parameters in d + Au collisions at sqrt(s_NN) = 200 GeV at forward and backward rapidities (y = +- 2.75), using data from the STAR forward time projection chambers. The contributions of different processes to baryon transport and particle production are probed exploiting the inherent asymmetry of the d + Au system. Comparisons to model calculations show that the baryon transport on the deuteron side is consistent with multiple collisions of the deuteron nucleons with gold participants. On the gold side HIJING based models do not describe the measured particle yields while models with initial state nuclear effects and/or hadronic rescattering do. The multichain model can provide a good description of the net baryon density in d + Au collisions at energies available at the BNL Relativistic Heavy Ion Collider, and the derived parameters of the model agree with those from nuclear collisions at lower energies.

STAR Collaboration; B. I. Abelev

2007-12-21T23:59:59.000Z

60

Overview of event-by-event analysis of high energy nuclear collisions  

E-Print Network [OSTI]

The event-by-event analysis of high energy nuclear collisions aims at revealing the richness of the underlying event structures and provide unique measures of dynamical fluctuations associated with QGP phase transition. The major challenge in these studies is to separate the dynamical fluctuations from the many other sources which contribute to the measured values. We present the fluctuations in terms of event multiplicity, mean transverse momentum, elliptic flow, source sizes, particle ratios and net charge distributions. In addition, we discuss the effect of long range correlations, disoriented chiral condensates and presence of jets. A brief review of various probes used for fluctuation studies and available experimental results are presented.

Tapan K. Nayak

2007-06-19T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Testing nuclear parton distributions with pA collisions at the LHC  

E-Print Network [OSTI]

Global perturbative QCD analyses, based on large data sets from electron-proton and hadron collider experiments, provide tight constraints on the parton distribution function (PDF) in the proton. The extension of these analyses to nuclear parton distributions (nPDF) has attracted much interest in recent years. nPDFs are needed as benchmarks for the characterization of hot QCD matter in nucleus-nucleus collisions, and attract further interest since they may show novel signatures of non-linear density-dependent QCD evolution. However, it is not known from first principles whether the factorization of long-range phenomena into process-independent parton distribution, which underlies global PDF extractions for the proton, extends to nuclear effects. As a consequence, assessing the reliability of nPDFs for benchmark calculations goes beyond testing the numerical accuracy of their extraction and requires phenomenological tests of the factorization assumption. Here we argue that a proton-nucleus collision program at the LHC would provide a set of measurements allowing for unprecedented tests of the factorization assumption underlying global nPDF fits.

Paloma Quiroga-Arias; Jose Guilherme Milhano; Urs Achin Wiedemann

2010-02-12T23:59:59.000Z

62

Energy and Atomic Mass Dependence of Nuclear Stopping Power in Relativistic Heavy-Ion Collisions in Interacting Gluon Model  

E-Print Network [OSTI]

We present a Monte-Carlo simulation of energy deposition process in relativistic heavy-ion collisions based on a new realization of the Interacting-Gluon-Model (IGM) for high energy $N-N$ collisions. In particular we show results for proton spectra from collisions of $E_{lab}=200 \\ GeV/N$ $^{32}$S beam incident on $^{32}$S target and analyze the energy and mass dependence of nuclear stopping power predicted by our model. Theoretical predictions for proton rapidity distributions of both $^{208}$Pb + $^{208}$Pb collisions at $E_{lab}=160 \\ GeV/N$ CERN SPS and $^{197}$Au + $^{197}$Au at $\\sqrt{s_{NN}}=200 \\ GeV$ BNL RHIC are given.

Q. J. Liu; W. Q. Chao; G. Wilk

1995-04-05T23:59:59.000Z

63

Monte Carlo approach for hadron azimuthal correlations in high energy proton and nuclear collisions  

E-Print Network [OSTI]

We use a Monte Carlo approach to study hadron azimuthal angular correlations in high energy proton-proton and central nucleus-nucleus collisions at the BNL Relativistic Heavy Ion Collider (RHIC) energies at mid-rapidity. We build a hadron event generator that incorporates the production of $2\\to 2$ and $2\\to 3$ parton processes and their evolution into hadron states. For nucleus-nucleus collisions we include the effect of parton energy loss in the Quark-Gluon Plasma using a modified fragmentation function approach. In the presence of the medium, for the case when three partons are produced in the hard scattering, we analyze the Monte Carlo sample in parton and hadron momentum bins to reconstruct the angular correlations. We characterize this sample by the number of partons that are able to hadronize by fragmentation within the selected bins. In the nuclear environment the model allows hadronization by fragmentation only for partons with momentum above a threshold $p_T^{{\\tiny{thresh}}}=2.4$ GeV. We argue that...

Ayala, Alejandro; Jalilian-Marian, Jamal; Magnin, J; Tejeda-Yeomans, Maria Elena

2012-01-01T23:59:59.000Z

64

Monte Carlo approach for hadron azimuthal correlations in high energy proton and nuclear collisions  

E-Print Network [OSTI]

We use a Monte Carlo approach to study hadron azimuthal angular correlations in high energy proton-proton and central nucleus-nucleus collisions at the BNL Relativistic Heavy Ion Collider (RHIC) energies at mid-rapidity. We build a hadron event generator that incorporates the production of $2\\to 2$ and $2\\to 3$ parton processes and their evolution into hadron states. For nucleus-nucleus collisions we include the effect of parton energy loss in the Quark-Gluon Plasma using a modified fragmentation function approach. In the presence of the medium, for the case when three partons are produced in the hard scattering, we analyze the Monte Carlo sample in parton and hadron momentum bins to reconstruct the angular correlations. We characterize this sample by the number of partons that are able to hadronize by fragmentation within the selected bins. In the nuclear environment the model allows hadronization by fragmentation only for partons with momentum above a threshold $p_T^{{\\tiny{thresh}}}=2.4$ GeV. We argue that one should treat properly the effect of those partons with momentum below the threshold, since their interaction with the medium may lead to showers of low momentum hadrons along the direction of motion of the original partons as the medium becomes diluted.

Alejandro Ayala; Isabel Dominguez; Jamal Jalilian-Marian; J. Magnin; Maria Elena Tejeda-Yeomans

2012-07-31T23:59:59.000Z

65

Fluctuations of Conserved Quantities in High Energy Nuclear Collisions at RHIC  

E-Print Network [OSTI]

Fluctuations of conserved quantities in heavy-ion collisions are used to probe the phase transition and the QCD critical point for the strongly interacting hot and dense nuclear matter. The STAR experiment has carried out moment analysis of net-proton (proxy for net-baryon (B)), net-kaon (proxy for net-strangeness (S)), and net-charge (Q). These measurements are important for understanding the quantum chromodynamics phase diagram. We present the analysis techniques used in the moment analysis by the STAR experiment and discuss the moments of net-proton and net-charge distributions from the first phase of the Beam Energy Scan program at the Relativistic Heavy Ion Collider.

Xiaofeng Luo

2015-01-13T23:59:59.000Z

66

Fluctuations of Conserved Quantities in High Energy Nuclear Collisions at RHIC  

E-Print Network [OSTI]

Fluctuations of conserved quantities in heavy-ion collisions are used to probe the phase transition and the QCD critical point for the strongly interacting hot and dense nuclear matter. The STAR experiment has carried out moment analysis of net-proton (proxy for net-baryon (B)), net-kaon (proxy for net-strangeness (S)), and net-charge (Q). These measurements are important for understanding the quantum chromodynamics phase diagram. We present the analysis techniques used in the moment analysis by the STAR experiment and discuss the moments of net-proton and net-charge distributions from the first phase of the Beam Energy Scan program at the Relativistic Heavy Ion Collider.

Luo, Xiaofeng

2015-01-01T23:59:59.000Z

67

Deep sub-threshold $?$ and $?$ production in nuclear collisions with the UrQMD transport model  

E-Print Network [OSTI]

We present results on deep sub threshold hyperon production in nuclear collisions, with the UrQMD transport model. Introducing anti-kaon+baryon and hyperon+hyperon strangeness exchange reactions we obtain a good description of experimental data on single strange hadron production in Ar+KCl reactions at $E_{lab}=1.76$ A GeV. We find that the hyperon strangeness exchange is the dominant process contributing to the $\\Xi^-$ yield, however remains short of explaining the $\\Xi^-/\\Lambda$ ratio measured with the HADES experiment. We also discuss possible reasons for the discrepancy with previous studies and the experimental results, finding that many details of the transport simulation may have significant effects on the final $\\Xi^-$ yield.

G. Graef; J. Steinheimer; Feng Li; Marcus Bleicher

2014-09-28T23:59:59.000Z

68

Evolution of the nuclear modification factors with rapidity and centrality in d+Au collisions at root(NN)-N-S=200 GeV  

E-Print Network [OSTI]

We report on a study of the transverse momentum dependence of nuclear modification factors R-dAu for charged hadrons produced in deuteron + gold collisions at roots(NN) = 200 GeV, as a function of collision centrality and ...

Sanders, Stephen J.

2004-12-10T23:59:59.000Z

69

Search for the QCD critical point in nuclear collisions at the CERN SPS  

E-Print Network [OSTI]

Pion production in nuclear collisions at the SPS is investigated with the aim to search, in a restricted domain of the phase diagram, for power-laws in the behavior of correlations which are compatible with critical QCD. We have analyzed interactions of nuclei of different size (p+p, C+C, Si+Si, Pb+Pb) at 158$A$ GeV adopting, as appropriate observables, scaled factorial moments in a search for intermittent fluctuations in transverse dimensions. The analysis is performed for $\\pi^+\\pi^-$ pairs with invariant mass very close to the two-pion threshold. In this sector one may capture critical fluctuations of the sigma component in a hadronic medium, even if the $\\sigma$-meson has no well defined vacuum state. It turns out that for the Pb+Pb system the proposed analysis technique cannot be applied without entering the invariant mass region with strong Coulomb correlations. As a result the treatment becomes inconclusive in this case. Our results for the other systems indicate the presence of power-law fluctuations in the freeze-out state of Si+Si approaching in size the prediction of critical QCD.

The NA49 Collaboration; N. G. Antoniou; F. K. Diakonos; G. Mavromanolakis

2010-05-19T23:59:59.000Z

70

Nuclear modification and elliptic flow measurements for $?$ mesons at $\\sqrt{s_{NN}}$ = 200 GeV d+Au and Au+Au collisions by PHENIX  

E-Print Network [OSTI]

We report the first results of the nuclear modification factors and elliptic flow of the phi mesons measured by the PHENIX experiment at RHIC in high luminosity Au+Au collisions at sqrt(sNN) = 200 GeV. The nuclear modification factors R_AA and R_CP of the phi follow the same trend of suppression as pi0's in Au+Au collisions. In d+Au collisions at sqrt(sNN) = 200 GeV, the phi mesons are not suppressed. The elliptic flow of the phi mesons, measured in the minimum bias Au+Au events, is statistically consistent with other identified particles.

Dipali Pal

2005-10-06T23:59:59.000Z

71

Experimental results and phenomenology of quarkonium production in relativistic nuclear collisions  

E-Print Network [OSTI]

An overview of recent measurements of quarkonium production in nucleus-nucleus collisions and their understanding in theoretical models is given.

A. Andronic

2014-10-15T23:59:59.000Z

72

Nuclear Stopping in Au Au Collisions at I. G. Bearden,7  

E-Print Network [OSTI]

available for particle production (excitation) in heavy ion collisions. This de- posited energy is essential, Copenhagen 2100, Denmark 8 Texas A&M University, College Station, Texas 17843, USA 9 Department of Physics, and increases to dN=dy 12 at y 3. The data show that collisions at this energy exhibit a high degree

73

Ramifications of the Nuclear Symmetry Energy for Neutron Stars, Nuclei, and Heavy-Ion Collisions  

E-Print Network [OSTI]

The pervasive role of the nuclear symmetry energy in establishing some nuclear static and dynamical properties, and in governing some attributes of neutron star properties is highlighted.

Andrew W. Steiner; Bao-An Li; Madappa Prakash

2007-11-29T23:59:59.000Z

74

Nuclear Effects on Hadron Production in d+Au and p+p Collisions at sqrt(s_NN)=200 GeV  

E-Print Network [OSTI]

PHENIX has measured the centrality dependence of mid-rapidity pion, kaon and proton transverse momentum distributions in d+Au and p+p collisions at sqrt(s_NN) = 200 GeV. The p+p data provide a reference for nuclear effects in d+Au and previously measured Au+Au collisions. Hadron production is enhanced in d+Au, relative to independent nucleon-nucleon scattering, as was observed in lower energy collisions. The nuclear modification factor for (anti) protons is larger than that for pions. The difference increases with centrality, but is not sufficient to account for the abundance of baryon production observed in central Au+Au collisions at RHIC. The centrality dependence in d+Au shows that the nuclear modification factor increases gradually with the number of collisions suffered by each participant nucleon. We also present comparisons with lower energy data as well as with parton recombination and other theoretical models of nuclear effects on particle production.

PHENIX Collaboration; S. S. Adler

2006-03-08T23:59:59.000Z

75

HARD PARTON PHYSICS IN HIGH ENERGY NUCLEAR COLLISIONS. PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP, VOLUME 17  

SciTech Connect (OSTI)

The RIKEN-BNL center workshop on ''Hard parton physics in high energy nuclear collisions'' was held at BNL from March 1st-5th! 1999. The focus of the workshop was on hard probes of nucleus-nucleus collisions that will be measured at RHIC with the PHENIX and STAR detectors. There were about 45 speakers and over 70 registered participants at the workshop, with roughly a quarter of the speakers from overseas. About 60% of the talks were theory talks. A nice overview of theory for RHIC was provided by George Sterman. The theoretical talks were on a wide range of topics in QCD which can be classified under the following: (a) energy loss and the Landau-Pomeranchuk-Migdal effect; (b) minijet production and equilibration; (c) small x physics and initial conditions; (d) nuclear parton distributions and shadowing; (e) spin physics; (f) photon, di-lepton, and charm production; and (g) hadronization, and simulations of high pt physics in event generators. Several of the experimental talks discussed the capabilities of the PHENIX and STAR detectors at RHIC in measuring high pt particles in heavy ion collisions. In general, these talks were included in the relevant theory sessions. A session was set aside to discuss the spin program at RHIC with polarized proton beams. In addition, there were speakers from 08, HERA, the fixed target experiments at Fermilab, and the CERN fixed target Pb+Pb program, who provided additional perspective on a range of issues of relevance to RHIC; from jets at the Tevatron, to saturation of parton distributions at HERA, and recent puzzling data on direct photon production in fixed target experiments, among others.

CARROLL,J.

1999-09-10T23:59:59.000Z

76

Particle number fluctuations in nuclear collisions within excluded volume hadron gas model  

E-Print Network [OSTI]

The multiplicity fluctuations are studied in the van der Waals excluded volume hadron-resonance gas model. The calculations are done in the grand canonical ensemble within the Boltzmann statistics approximation. The scaled variances for positive, negative and all charged hadrons are calculated along the chemical freeze-out line of nucleus-nucleus collisions at different collision energies. The multiplicity fluctuations are found to be suppressed in the van der Waals gas. The numerical calculations are presented for two values of hard-core hadron radius, $r=0.3$ fm and 0.5 fm, as well as for the upper limit of the excluded volume suppression effects.

M. I. Gorenstein; M. Hauer; D. O. Nikolajenko

2007-02-26T23:59:59.000Z

77

Nuclear astrophysics studies with ultra-peripheral heavy-ion collisions  

E-Print Network [OSTI]

I describe in very simple terms the theoretical tools needed to investigate ultra-peripheral nuclear reactions for nuclear astrophysics purposes. For a more detailed account, see arXiv:0908.4307.

C. A. Bertulani

2009-12-17T23:59:59.000Z

78

Nuclear stopping in Au+Au collisions at root s(NN) = 200 GeV  

E-Print Network [OSTI]

Transverse momentum spectra and rapidity densities, dN/dy, of protons, antiprotons, and net protons (p-(p) over bar) from central (0%-5%) Au+Au collisions at roots(NN)=200 GeV were measured with the BRAHMS experiment within ...

Ito, H.; Kim, E. J.; Murray, Michael J.; Norris, J.; Sanders, Stephen J.

2004-09-01T23:59:59.000Z

79

Sensitivity of Pion versus Parton-Jet Nuclear Modification Factors to the Path-Length Dependence of Jet-Energy Loss at RHIC and LHC  

E-Print Network [OSTI]

We compare the jet-path length and beam-energy dependence of the pion nuclear modification factor and a parton-jet nuclear modification factor at RHIC and LHC. We contrast predictions based on a linear pQCD and a highly non-linear hybrid-AdS holographic model of jet-energy loss. We find that both models require a reduction of the jet-medium coupling from RHIC to LHC to account for the measured pion nuclear modification factor. In case of the parton-jet nuclear modification factor, however, which serves as a lower bound for the LO jet nuclear modification factor of reconstructed jets, the extracted data can be characterized without a reduced jet-medium coupling at LHC energies. We conclude that while reconstructed jets are sensitive to both quarks and gluons and thus provide more information than the pion nuclear modification factor, their information regarding the jet-medium coupling is limited due to the superimposition with NLO and medium effects. Hence, a detailed description of the underlying physics requ...

Betz, Barbara

2015-01-01T23:59:59.000Z

80

NUCLEAR SCIENCE ANNUAL REPORT 1977-1978  

E-Print Network [OSTI]

A Relation Between Nuclear Dynamics and the RenormalizationMultiplicity Distributions in Nuclear Collision M. GyulassyHigh Energy Nuclear Collisions in the Resonance Dominated

Schroeder, L.S.

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Prospects for quarkonia production studies in U+U collisions  

E-Print Network [OSTI]

Collisions of deformed uranium nuclei provide a unique opportunity to study the spatial dependence of charmonium in-medium effects. By selecting the orientations of the colliding nuclei, different path lengths through the nuclear medium could be selected within the same experimental environment. In addition, higher energy densities can be achieved in U+U collisions relative to Au+Au collisions. In this paper, we investigate the prospects for charmonium studies with U+U collisions. We discuss the effects of shadowing and nuclear absorption on the J/\\psi\\ yield. We introduce a new observable which could help distinguish between different types of J/\\psi\\ interactions in hot and dense matter.

Daniel Kiko?a; Grazyna Odyniec; Ramona Vogt

2011-11-20T23:59:59.000Z

82

Prospects for quarkonia production studies in U+U collisions  

E-Print Network [OSTI]

Collisions of deformed uranium nuclei provide a unique opportunity to study the spatial dependence of charmonium in-medium effects. By selecting the orientations of the colliding nuclei, different path lengths through the nuclear medium could be selected within the same experimental environment. In addition, higher energy densities can be achieved in U+U collisions relative to Au+Au collisions. In this paper, we investigate the prospects for charmonium studies with U+U collisions. We discuss the effects of shadowing and nuclear absorption on the J/\\psi\\ yield. We introduce a new observable which could help distinguish between different types of J/\\psi\\ interactions in hot and dense matter.

Kiko?a, Daniel; Vogt, Ramona; 10.1103/PhysRevC.84.054907

2011-01-01T23:59:59.000Z

83

Nuclear modification factor of nonphotonic electrons in heavy-ion collisions, and the heavy-flavor baryon-to-meson ratio  

E-Print Network [OSTI]

The nuclear modification factor R(AA) of nonphotonic electrons in Au + Au collisions at root(S)NN = 200 GeV is studied by considering the decays of heavy-flavor hadrons produced in a quark coalescence model. Although an enhanced Lambda(c)/D(0) ratio...

Oh, Yongseok; Ko, Che Ming.

2009-01-01T23:59:59.000Z

84

De-Confinement and Clustering of Color Sources in Nuclear Collisions  

E-Print Network [OSTI]

A brief introduction of the relationship of string percolation to the Quantum Chromo Dynamics (QCD) phase diagram is presented. The behavior of the Polyakov loop close to the critical temperature is studied in terms of the color fields inside the clusters of overlapping strings, which are produced in high energy hadronic collisions. The non-Abelian nature of the color fields implies an enhancement of the transverse momentum and a suppression of the multiplicities relative to the non overlapping case. The prediction of this framework are compared with experimental results from the SPS, RHIC and LHC for $pp$ and AA collisions. Rapidity distributions, probability distributions of transverse momentum and multiplicities, Bose-Einstein correlations, elliptic flow and ridge structures are used to evaluate these comparison. The thermodynamical quantities, the temperature, and energy density derived from RHIC and LHC data and Color String Percolation Model (CSPM) are used to obtain the shear viscosity to entropy densi...

Braun, M A; Hirsch, A S; Pajares, C; Scharenberg, R P; Srivastava, B K

2015-01-01T23:59:59.000Z

85

Long range rapidity correlations and jet production in high energy nuclear collisions  

SciTech Connect (OSTI)

The STAR Collaboration at RHIC presents a systematic study of high transverse momentum charged di-hadron correlations at small azimuthal pair separation {Delta}{phi}, in d+Au and central Au+Au collisions at {radical}s{sub NN} = 200 GeV. Significant correlated yield for pairs with large longitudinal separation {Delta}{eta} is observed in central Au+Au, in contrast to d+Au collisions. The associated yield distribution in {Delta}{eta} x {delta}{phi} can be decomposed into a narrow jet-like peak at small angular separation which has a similar shape to that found in d+Au collisions, and a component which is narrow in {Delta}{phi} and depends only weakly on {Delta}{eta}, the 'ridge'. Using two systematically independent analyses, finite ridge yield is found to persist for trigger p{sub t} > 6 GeV/c, indicating that it is correlated with jet production. The transverse momentum spectrum of hadrons comprising the ridge is found to be similar to that of bulk particle production in the measured range (2 < p{sub t} < 4 GeV/c).

STAR Collaboration; Abelev, Betty

2010-07-05T23:59:59.000Z

86

TEST OF SQUARE LAW FOR DEUTERON FORMATION IN RELATIVISTIC NUCLEAR COLLISIONS  

E-Print Network [OSTI]

OF SQUARE lAW FOR m::utERONFORMATION IN RELATIVISTIC NUCLEAROF SQUARE LAW FOR DEUTERON FORMATION IN RELATIVISTIC NUCLEARlaw for high energy deuterons and protons produced in nuclear

Noack, C.C.

2013-01-01T23:59:59.000Z

87

Production of e+e- Pairs Accompanied by Nuclear Dissociation in Ultra-peripheral Heavy Ion Collisions  

SciTech Connect (OSTI)

We present the first data on e{sup +}e{sup -} pair production accompanied by nuclear breakup in ultra-peripheral gold-gold collisions at a center of mass energy of 200 GeV per nucleon pair. The nuclear breakup requirement selects events at small impact parameters, where higher-order corrections to the pair production cross section should be enhanced. We compare the pair kinematic distributions with two calculations: one based on the equivalent photon approximation, and the other using lowest-order quantum electrodynamics (QED); the latter includes the photon virtuality. The cross section, pair mass, rapidity and angular distributions are in good agreement with both calculations. The pair transverse momentum, p{sub T}, spectrum agrees with the QED calculation, but not with the equivalent photon approach. We set limits on higher-order contributions to the cross section. The e{sup +} and e{sup -} p{sub T} spectra are similar, with no evidence for interference effects due to higher-order diagrams.

Adams, J.; Adler, C.; Aggarwal, M.M.; Ahammed, Z.; Allgower, C.; Amonett, J.; Anderson, B.D.; Anderson, M.; Arkhipkin, D.; Averichev, G.S.; Bai, Y.; Balewski, J.; Barannikova, O.; Barnby, L.S.; Baudot, J.; Bekele, S.; Belaga, V.V.; Bellwied, R.; Berger, J.; Bichsel, H.; Billmeier, A.; Bland, L.C.; Blyth, C.O.; Bonner, B.E.; Boucham, A.; Brandin, A.; Bravar, A.; Cadman, R.V.; Caines, H.; Calderon de la Barca Sanchez, M.; Cardenas, A.; Carroll, J.; Castillo, J.; Castro, M.; Cebra, D.; Chaloupka, P.; Chattopadhyay, S.; Chen, Y.; Chernenko, S.P.; Cherney, M.; Chikanian, A.; Choi, B.; Christie, W.; Coffin, J.P.; Cormier, T.M.; Corral, M.M.; Cramer, J.G.; Crawford, H.J.; Deng, W.S.; Derevschikov, A.A.; Didenko, L.; Dietel, T.; Draper, J.E.; Dunin, V.B.; Dunlop, J.C.; Eckardt, V.; Efimov, L.G.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Fachini, P.; Faine, V.; Faivre, J.; Fatemi, R.; Filimonov, K.; Finch, E.; Fisyak, Y.; Flierl, D.; Foley, K.J.; Fu, J.; Gagliardi, C.A.; Gagunashvili, N.; Gans, J.; Gaudichet, L.; Germain, M.; Geurts, F.; Ghazikhanian, V.; Grachov, O.; Grigoriev, V.; Guedon, M.; Guertin, S.M.; Gushin, E.; Hallman, T.J.; Hardtke, D.; Harris, J.W.; Heinz, M.; Henry, T.W.; Heppelmann, S.; Herston, T.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffmann, G.W.; Horsley, M.; Huang, H.Z.; Humanic, T.J.; Igo, G.; Ishihara, A.; Ivanshin, Yu.I.; Jacobs, P.; Jacobs, W.W.; Janik, M.; Johnson, I.; Jones, P.G.; Judd, E.G.; Kaneta, M.; Kaplan, M.; Keane, D.; Kiryluk, J.; Kisiel, A.; Klay, J.; Klein, S.R.; Klyachko, A.; Kollegger, T.; Konstantinov, A.; Kopytine, S.M.; Kotchenda, L.; Kovalenko, A.D.; Kramer, M.; Kravtsov, P.; Krueger, K.; Kuhn, C.; Kulikov, A.I.; Kunde, G.J.; Kunz, C.L.; Kutuev, R.K.; Kuznetsov, A.A.; Lamont, M.A.C.; Landgraf, J.M.; Lange, S.; Lansdell, C.P.; Lasiuk, B.; Laue, F.; Lauret, J.; Lebedev, A.; Lednicky, R.; Leontiev, V.M.; LeVine, M.J.; Li, Q.; Lindenbaum, S.J.; Lisa, M.A.; Liu, F.; Liu, L.; Liu, Z.; et al.

2004-04-07T23:59:59.000Z

88

Observable measures of critical behavior in high-energy nuclear collisions  

E-Print Network [OSTI]

Critical behaviors of quark-hadron phase transition in high-energy heavy-ion collisions are investigated with the aim of identifying hadronic observables. The surface of the plasma cylinder is mapped onto a 2D lattice. The Ising model is used to simulate configurations corresponding to cross-over transitions in accordance to the findings of QCD lattice gauge theory. Hadrons are formed in clusters of all sizes. Various measures are examined to quantify the fluctuations of the cluster sizes and of the voids among the clusters. The canonical power-law behaviors near the critical temperature are found for appropriately chosen measures. Since the temperature is not directly observable, attention is given to the problem of finding observable measures. It is demonstrated that for the measures considered the dependence on the final-state randomization is weak. Thus the critical behavior of the measures proposed is likely to survive the scattering effect of the hadron gas in the final state.

Rudolph C. Hwa

2000-07-19T23:59:59.000Z

89

Heavy flavours in high-energy nuclear collisions: quenching, flow and correlations  

E-Print Network [OSTI]

We present results for the quenching, elliptic flow and azimuthal correlations of heavy flavour particles in high-energy nucleus-nucleus collisions obtained through the POWLANG transport setup, developed in the past to study the propagation of heavy quarks in the Quark-Gluon Plasma and here extended to include a modeling of their hadronization in the presence of a medium. Hadronization is described as occurring via the fragmentation of strings with endpoints given by the heavy (anti-)quark Q(Qbar) and a thermal parton $qbar(q)$ from the medium. The flow of the light quarks is shown to affect significantly the R_AA} and v_2 of the final D mesons, leading to a better agreement with the experimental data.

A. Beraudo; A. De Pace; M. Monteno; M. Nardi; F. Prino

2014-12-01T23:59:59.000Z

90

Coupled-channels density-matrix approach to low-energy nuclear collision dynamics: A technique for quantifying quantum decoherence effects on reaction observables  

E-Print Network [OSTI]

The coupled-channels density-matrix technique for nuclear reaction dynamics, which is based on the Liouville-von Neumann equation with Lindblad dissipative terms, is developed with the inclusion of full angular momentum couplings. It allows a quantitative study of the role and importance of quantum decoherence in nuclear scattering. Formulae of asymptotic observables that can reveal effects of quantum decoherence are given. A method for extracting energy-resolved scattering information from the time-dependent density matrix is introduced. As an example, model calculations are carried out for the low-energy collision of the $^{16}$O projectile on the $^{154}$Sm target.

Alexis Diaz-Torres

2010-10-18T23:59:59.000Z

91

Nuclear modification factor in intermediate-energy heavy-ion collisions  

E-Print Network [OSTI]

The transverse momentum dependent nuclear modification factors (NMF), namely $R_{CP}$, is investigated for protons produced in Au + Au at 1$A$ GeV within the framework of the isospin-dependent quantum molecular dynamics (IQMD) model. It is found that the radial collective motion during the expansion stage affects the NMF at low transverse momentum a lot. By fitting the transverse mass spectra of protons with the distribution function from the Blast-Wave model, the magnitude of radial flow can be extracted. After removing the contribution from radial flow, the $R_{CP}$ can be regarded as a thermal one and is found to keep unitary at transverse momentum lower than 0.6 GeV/c and enhance at higher transverse momentum, which can be attributed to Cronin effect.

M. Lv; Y. G. Ma; G. Q. Zhang; J. H. Chen; D. Q. Fang

2014-04-16T23:59:59.000Z

92

Studies of fluctuation processes in nuclear collisions. Progress report, March 1, 1993--April 30, 1994  

SciTech Connect (OSTI)

This report summarizes the progress on grant No.FG05-89ER40530 during the period March 1, 1993 to April 30, 1994. By extending our previous work on the fluid dynamical treatment of the nuclear collective motion, we deduced from the Boltzmann-Langevin (BL) model a set of transport equations for N collective variables and calculated the associated transport coefficients. Work has also continued on investigating the relation between the BUU model and the BL model for the average evolution. The principle investigator spent a fruitful summer (1993) at LBL, where in collaboration with J. Raindrop, we developed a numerical method for simulating the stochastic evolution of the phase-space density near local equilibrium. Two papers have appeared in Phys. Rev. C and Nucl. Phys. A, two papers have been accepted for publication, both in Nucl. Phys. A, and two manuscripts have been submitted to Z. Phys. A for publication. Several seminars/contributed talks were given at various meetings and an invited talk was presented at the NATO Advanced Study Institution Hot and Dense Matter, Bodrum/Turkey.

Ayik, S.

1994-05-01T23:59:59.000Z

93

Study of $J/?$ production and cold nuclear matter effects in $p$Pb collisions at $\\sqrt{s_{NN}}=5 \\mathrm{TeV}$  

E-Print Network [OSTI]

The production of $J/\\psi$ mesons with rapidity $1.5collisions at a nucleon-nucleon centre-of-mass energy $\\sqrt{s_{NN}}=5 \\mathrm{TeV}$. The analysis is based on a data sample corresponding to an integrated luminosity of about $1.6 \\mathrm{nb}^{-1}$. For the first time the nuclear modification factor and forward-backward production ratio are determined separately for prompt $J/\\psi$ mesons and $J/\\psi$ from $b$-hadron decays. Clear suppression of prompt $J/\\psi$ production with respect to proton-proton collisions at large rapidity is observed, while the production of $J/\\psi$ from $b$-hadron decays is less suppressed. These results show good agreement with available theoretical predictions. The measurement shows that cold nuclear matter effects are important for interpretations of the related quark-gluon plasma signatures in heavy-ion collisions.

LHCb collaboration; R. Aaij; B. Adeva; M. Adinolfi; C. Adrover; A. Affolder; Z. Ajaltouni; J. Albrecht; F. Alessio; M. Alexander; S. Ali; G. Alkhazov; P. Alvarez Cartelle; A. A. Alves Jr; S. Amato; S. Amerio; Y. Amhis; L. Anderlini; J. Anderson; R. Andreassen; J. E. Andrews; R. B. Appleby; O. Aquines Gutierrez; F. Archilli; A. Artamonov; M. Artuso; E. Aslanides; G. Auriemma; M. Baalouch; S. Bachmann; J. J. Back; A. Badalov; C. Baesso; V. Balagura; W. Baldini; R. J. Barlow; C. Barschel; S. Barsuk; W. Barter; Th. Bauer; A. Bay; J. Beddow; F. Bedeschi; I. Bediaga; S. Belogurov; K. Belous; I. Belyaev; E. Ben-Haim; G. Bencivenni; S. Benson; J. Benton; A. Berezhnoy; R. Bernet; M. -O. Bettler; M. van Beuzekom; A. Bien; S. Bifani; T. Bird; A. Bizzeti; P. M. Bj\\ornstad; T. Blake; F. Blanc; J. Blouw; S. Blusk; V. Bocci; A. Bondar; N. Bondar; W. Bonivento; S. Borghi; A. Borgia; T. J. V. Bowcock; E. Bowen; C. Bozzi; T. Brambach; J. van den Brand; J. Bressieux; D. Brett; M. Britsch; T. Britton; N. H. Brook; H. Brown; A. Bursche; G. Busetto; J. Buytaert; S. Cadeddu; O. Callot; M. Calvi; M. Calvo Gomez; A. Camboni; P. Campana; D. Campora Perez; A. Carbone; G. Carboni; R. Cardinale; A. Cardini; H. Carranza-Mejia; L. Carson; K. Carvalho Akiba; G. Casse; L. Cassina; L. Castillo Garcia; M. Cattaneo; Ch. Cauet; R. Cenci; M. Charles; Ph. Charpentier; S. -F. Cheung; N. Chiapolini; M. Chrzaszcz; K. Ciba; X. Cid Vidal; G. Ciezarek; P. E. L. Clarke; M. Clemencic; H. V. Cliff; J. Closier; C. Coca; V. Coco; J. Cogan; E. Cogneras; P. Collins; A. Comerma-Montells; A. Contu; A. Cook; M. Coombes; S. Coquereau; G. Corti; B. Couturier; G. A. Cowan; D. C. Craik; S. Cunliffe; R. Currie; C. D'Ambrosio; P. David; P. N. Y. David; A. Davis; I. De Bonis; K. De Bruyn; S. De Capua; M. De Cian; J. M. De Miranda; L. De Paula; W. De Silva; P. De Simone; D. Decamp; M. Deckenhoff; L. Del Buono; N. Déléage; D. Derkach; O. Deschamps; F. Dettori; A. Di Canto; H. Dijkstra; M. Dogaru; S. Donleavy; F. Dordei; A. Dosil Suárez; D. Dossett; A. Dovbnya; F. Dupertuis; P. Durante; R. Dzhelyadin; A. Dziurda; A. Dzyuba; S. Easo; U. Egede; V. Egorychev; S. Eidelman; D. van Eijk; S. Eisenhardt; U. Eitschberger; R. Ekelhof; L. Eklund; I. El Rifai; Ch. Elsasser; A. Falabella; C. Färber; C. Farinelli; S. Farry; D. Ferguson; V. Fernandez Albor; F. Ferreira Rodrigues; M. Ferro-Luzzi; S. Filippov; M. Fiore; C. Fitzpatrick; M. Fontana; F. Fontanelli; R. Forty; O. Francisco; M. Frank; C. Frei; M. Frosini; E. Furfaro; A. Gallas Torreira; D. Galli; M. Gandelman; P. Gandini; Y. Gao; J. Garofoli; P. Garosi; J. Garra Tico; L. Garrido; C. Gaspar; R. Gauld; E. Gersabeck; M. Gersabeck; T. Gershon; Ph. Ghez; V. Gibson; L. Giubega; V. V. Gligorov; C. Göbel; D. Golubkov; A. Golutvin; A. Gomes; P. Gorbounov; H. Gordon; M. Grabalosa Gándara; R. Graciani Diaz; L. A. Granado Cardoso; E. Graugés; G. Graziani; A. Grecu; E. Greening; S. Gregson; P. Griffith; O. Grünberg; B. Gui; E. Gushchin; Yu. Guz; T. Gys; C. Hadjivasiliou; G. Haefeli; C. Haen; S. C. Haines; S. Hall; B. Hamilton; T. Hampson; S. Hansmann-Menzemer; N. Harnew; S. T. Harnew; J. Harrison; T. Hartmann; J. He; T. Head; V. Heijne; K. Hennessy; P. Henrard; J. A. Hernando Morata; E. van Herwijnen; M. Heß; A. Hicheur; E. Hicks; D. Hill; M. Hoballah; C. Hombach; W. Hulsbergen; P. Hunt; T. Huse; N. Hussain; D. Hutchcroft; D. Hynds; V. Iakovenko; M. Idzik; P. Ilten; R. Jacobsson; A. Jaeger; E. Jans; P. Jaton; A. Jawahery; F. Jing; M. John; D. Johnson; C. R. Jones; C. Joram; B. Jost; M. Kaballo; S. Kandybei; W. Kanso; M. Karacson; T. M. Karbach; I. R. Kenyon; T. Ketel; B. Khanji; O. Kochebina; I. Komarov; R. F. Koopman; P. Koppenburg; M. Korolev; A. Kozlinskiy; L. Kravchuk; K. Kreplin; M. Kreps; G. Krocker; P. Krokovny; F. Kruse; M. Kucharczyk; V. Kudryavtsev; K. Kurek; T. Kvaratskheliya; V. N. La Thi; D. Lacarrere; G. Lafferty; A. Lai; D. Lambert; R. W. Lambert; E. Lanciotti; G. Lanfranchi; C. Langenbruch; T. Latham; C. Lazzeroni; R. Le Gac; J. van Leerdam; J. -P. Lees; R. Lefčvre; A. Leflat; J. Lefrançois; S. Leo; O. Leroy; T. Lesiak; B. Leverington; Y. Li; L. Li Gioi; M. Liles; R. Lindner; C. Linn; B. Liu; G. Liu; S. Lohn; I. Longstaff; J. H. Lopes; N. Lopez-March; H. Lu; D. Lucchesi; J. Luisier; H. Luo; O. Lupton; F. Machefert; I. V. Machikhiliyan; F. Maciuc; O. Maev; S. Malde; G. Manca; G. Mancinelli; J. Maratas; U. Marconi; P. Marino; R. Märki; J. Marks; G. Martellotti; A. Martens; A. Martín Sánchez; M. Martinelli; D. Martinez Santos; D. Martins Tostes; A. Martynov; A. Massafferri; R. Matev; Z. Mathe; C. Matteuzzi; E. Maurice; A. Mazurov; J. McCarthy; A. McNab; R. McNulty; B. McSkelly; B. Meadows; F. Meier; M. Meissner; M. Merk; D. A. Milanes; M. -N. Minard; J. Molina Rodriguez; S. Monteil; D. Moran; P. Morawski; A. Mordŕ; M. J. Morello; R. Mountain; I. Mous; F. Muheim; K. Müller

2014-03-25T23:59:59.000Z

94

Probing the small-$x$ nuclear gluon distributions with isolated photons at forward rapidities in p+Pb collisions at the LHC  

E-Print Network [OSTI]

Inclusive direct photon production in p+Pb collisions at the LHC is studied within the NLO perturbative QCD. Our aim is to quantify the dominant $x$ regions probed at different rapidities and to identify the best conditions for testing the nuclear gluon parton distribution functions (nPDFs) at small $x$. A comparison to the inclusive pion production reveals that from these two processes the photons carry more sensitivity to the small-$x$ partons and that this sensitivity can be further increased by imposing an isolation cut for the photon events. The details of the isolation criteria, however, seem to make only a small difference to the studied $x$ sensitivity and have practically no effect on the expected nuclear modifications. We consider also the yield asymmetry between forward and backward rapidities which can be used to probe the nPDFs irrespectively of whether an accurate p+p baseline is available.

Ilkka Helenius; Kari J. Eskola; Hannu Paukkunen

2014-06-06T23:59:59.000Z

95

Particle spectra and HBT radii for simulated central nuclear collisions of C+C, Al+Al, Cu+Cu, Au+Au, and Pb+Pb from Sqrt(s)=62.4-2760 GeV  

E-Print Network [OSTI]

We study the temperature profile, pion spectra and HBT radii in central symmetric and boost-invariant nuclear collisions using a super hybrid model for heavy-ion collisions (SONIC) combining pre-equilibrium flow with viscous hydrodynamics and late-stage hadronic rescatterings. In particular, we simulate Pb+Pb collisions at Sqrt(s)=2.76 TeV, Au+Au, Cu+Cu, Al+Al, and C+C collisions at Sqrt(s)=200 GeV and Au+Au, Cu+Cu collisions at Sqrt(s)=62.4 GeV. We find that SONIC provides a good match to the pion spectra and HBT radii for all collision systems and energies, confirming earlier work that a combination of pre-equilibrium flow, viscosity and QCD equation of state can resolve the so-called HBT puzzle. For reference, we also show p+p collisions at Sqrt(s)=7 TeV. We make tabulated data for the 2+1 dimensional temperature evolution of all systems publicly available for the use in future jet energy loss or similar studies.

M. Habich; J. L. Nagle; P. Romatschke

2015-02-23T23:59:59.000Z

96

Study of $?$ production and cold nuclear matter effects in pPb collisions at $\\sqrt{s_{NN}}=5~\\mathrm{TeV}$  

E-Print Network [OSTI]

Production of $\\Upsilon$ mesons in proton-lead collisions at a nucleon-nucleon centre-of-mass energy $\\sqrt{s_{NN}}=5 \\mathrm{TeV}$ is studied with the LHCb detector. The analysis is based on a data sample corresponding to an integrated luminosity of $1.6 \\mathrm{nb}^{-1}$. The $\\Upsilon$ mesons of transverse momenta up to $15 \\mathrm{GeV}/c$ are reconstructed in the dimuon decay mode. The rapidity coverage in the centre-of-mass system is $1.5nuclear modification factor for $\\Upsilon(1S)$ mesons are determined. The data are compatible with the predictions for a suppression of $\\Upsilon(1S)$ production with respect to proton-proton collisions in the forward region, and an enhancement in the backward region. The suppression is found to be smaller than in the case of prompt $J/\\psi$ mesons.

LHCb collaboration; R. Aaij; B. Adeva; M. Adinolfi; A. Affolder; Z. Ajaltouni; J. Albrecht; F. Alessio; M. Alexander; S. Ali; G. Alkhazov; P. Alvarez Cartelle; A. A. Alves Jr; S. Amato; S. Amerio; Y. Amhis; L. An; L. Anderlini; J. Anderson; R. Andreassen; M. Andreotti; J. E. Andrews; R. B. Appleby; O. Aquines Gutierrez; F. Archilli; A. Artamonov; M. Artuso; E. Aslanides; G. Auriemma; M. Baalouch; S. Bachmann; J. J. Back; A. Badalov; V. Balagura; W. Baldini; R. J. Barlow; C. Barschel; S. Barsuk; W. Barter; V. Batozskaya; A. Bay; L. Beaucourt; J. Beddow; F. Bedeschi; I. Bediaga; S. Belogurov; K. Belous; I. Belyaev; E. Ben-Haim; G. Bencivenni; S. Benson; J. Benton; A. Berezhnoy; R. Bernet; M. -O. Bettler; M. van Beuzekom; A. Bien; S. Bifani; T. Bird; A. Bizzeti; P. M. Bjřrnstad; T. Blake; F. Blanc; J. Blouw; S. Blusk; V. Bocci; A. Bondar; N. Bondar; W. Bonivento; S. Borghi; A. Borgia; M. Borsato; T. J. V. Bowcock; E. Bowen; C. Bozzi; T. Brambach; J. van den Brand; J. Bressieux; D. Brett; M. Britsch; T. Britton; J. Brodzicka; N. H. Brook; H. Brown; A. Bursche; G. Busetto; J. Buytaert; S. Cadeddu; R. Calabrese; M. Calvi; M. Calvo Gomez; A. Camboni; P. Campana; D. Campora Perez; A. Carbone; G. Carboni; R. Cardinale; A. Cardini; H. Carranza-Mejia; L. Carson; K. Carvalho Akiba; G. Casse; L. Cassina; L. Castillo Garcia; M. Cattaneo; Ch. Cauet; R. Cenci; M. Charles; Ph. Charpentier; S. Chen; S. -F. Cheung; N. Chiapolini; M. Chrzaszcz; K. Ciba; X. Cid Vidal; G. Ciezarek; P. E. L. Clarke; M. Clemencic; H. V. Cliff; J. Closier; V. Coco; J. Cogan; E. Cogneras; P. Collins; A. Comerma-Montells; A. Contu; A. Cook; M. Coombes; S. Coquereau; G. Corti; M. Corvo; I. Counts; B. Couturier; G. A. Cowan; D. C. Craik; M. Cruz Torres; S. Cunliffe; R. Currie; C. D'Ambrosio; J. Dalseno; P. David; P. N. Y. David; A. Davis; K. De Bruyn; S. De Capua; M. De Cian; J. M. De Miranda; L. De Paula; W. De Silva; P. De Simone; D. Decamp; M. Deckenhoff; L. Del Buono; N. Déléage; D. Derkach; O. Deschamps; F. Dettori; A. Di Canto; H. Dijkstra; S. Donleavy; F. Dordei; M. Dorigo; A. Dosil Suárez; D. Dossett; A. Dovbnya; G. Dujany; F. Dupertuis; P. Durante; R. Dzhelyadin; A. Dziurda; A. Dzyuba; S. Easo; U. Egede; V. Egorychev; S. Eidelman; S. Eisenhardt; U. Eitschberger; R. Ekelhof; L. Eklund; I. El Rifai; Ch. Elsasser; S. Ely; S. Esen; T. Evans; A. Falabella; C. Färber; C. Farinelli; N. Farley; S. Farry; D. Ferguson; V. Fernandez Albor; F. Ferreira Rodrigues; M. Ferro-Luzzi; S. Filippov; M. Fiore; M. Fiorini; M. Firlej; C. Fitzpatrick; T. Fiutowski; M. Fontana; F. Fontanelli; R. Forty; O. Francisco; M. Frank; C. Frei; M. Frosini; J. Fu; E. Furfaro; A. Gallas Torreira; D. Galli; S. Gallorini; S. Gambetta; M. Gandelman; P. Gandini; Y. Gao; J. Garofoli; J. Garra Tico; L. Garrido; C. Gaspar; R. Gauld; L. Gavardi; E. Gersabeck; M. Gersabeck; T. Gershon; Ph. Ghez; A. Gianelle; S. Giani'; V. Gibson; L. Giubega; V. V. Gligorov; C. Göbel; D. Golubkov; A. Golutvin; A. Gomes; H. Gordon; C. Gotti; M. Grabalosa Gándara; R. Graciani Diaz; L. A. Granado Cardoso; E. Graugés; G. Graziani; A. Grecu; E. Greening; S. Gregson; P. Griffith; L. Grillo; O. Grünberg; B. Gui; E. Gushchin; Yu. Guz; T. Gys; C. Hadjivasiliou; G. Haefeli; C. Haen; S. C. Haines; S. Hall; B. Hamilton; T. Hampson; X. Han; S. Hansmann-Menzemer; N. Harnew; S. T. Harnew; J. Harrison; T. Hartmann; J. He; T. Head; V. Heijne; K. Hennessy; P. Henrard; L. Henry; J. A. Hernando Morata; E. van Herwijnen; M. Heß; A. Hicheur; D. Hill; M. Hoballah; C. Hombach; W. Hulsbergen; P. Hunt; N. Hussain; D. Hutchcroft; D. Hynds; M. Idzik; P. Ilten; R. Jacobsson; A. Jaeger; J. Jalocha; E. Jans; P. Jaton; A. Jawahery; M. Jezabek; F. Jing; M. John; D. Johnson; C. R. Jones; C. Joram; B. Jost; N. Jurik; M. Kaballo; S. Kandybei; W. Kanso; M. Karacson; T. M. Karbach; M. Kelsey; I. R. Kenyon; T. Ketel; B. Khanji; C. Khurewathanakul; S. Klaver; O. Kochebina; M. Kolpin; I. Komarov; R. F. Koopman; P. Koppenburg; M. Korolev; A. Kozlinskiy; L. Kravchuk; K. Kreplin; M. Kreps; G. Krocker; P. Krokovny; F. Kruse; M. Kucharczyk; V. Kudryavtsev; K. Kurek; T. Kvaratskheliya; V. N. La Thi; D. Lacarrere; G. Lafferty; A. Lai; D. Lambert; R. W. Lambert; E. Lanciotti; G. Lanfranchi; C. Langenbruch; B. Langhans; T. Latham; C. Lazzeroni; R. Le Gac; J. van Leerdam; J. -P. Lees; R. Lefčvre; A. Leflat; J. Lefrançois; S. Leo; O. Leroy; T. Lesiak; B. Leverington; Y. Li; M. Liles; R. Lindner; C. Linn; F. Lionetto; B. Liu; G. Liu; S. Lohn; I. Longstaff; J. H. Lopes; N. Lopez-March; P. Lowdon; H. Lu; D. Lucchesi; H. Luo; A. Lupato; E. Luppi; O. Lupton; F. Machefert; I. V. Machikhiliyan; F. Maciuc; O. Maev; S. Malde; G. Manca; G. Mancinelli; M. Manzali; J. Maratas; J. F. Marchand; U. Marconi; C. Marin Benito; P. Marino; R. Märki; J. Marks; G. Martellotti; A. Martens; A. Martín Sánchez; M. Martinelli

2014-10-15T23:59:59.000Z

97

Charmonium and open charm production in nuclear collisions at SPS/FAIR energies and the possible influence of a hot hadronic medium  

E-Print Network [OSTI]

We provide predictions for charmonium and open charm production in nuclear collisions at SPS/FAIR energies within the framework of the statistical hadronization model. The increasing importance at lower energies of Lambda_c production is demonstrated and provides a challenge for future experiments. We also demonstrate that, because of the large charm quark mass and the different timescales for charm quark and charmed hadron production, possible modifications of charmed hadrons in the hot hadronic medium do not lead to measurable changes in cross sections for D-meson production. A possible influence of medium effects can be seen, however, in yields of charmonium. These effects are visible at all energies and results are presented for the energy range between charm threshold and RHIC energy.

A. Andronic; P. Braun-Munzinger; K. Redlich; J. Stachel

2007-10-26T23:59:59.000Z

98

Central-to-peripheral nuclear modification factors in Pb-Pb collisions at sqrt{s_NN} = 17.3 GeV  

E-Print Network [OSTI]

We present central-to-peripheral nuclear modification factors, R_CP, for the p_T distributions of K^0_S, Lambda, Anti-Lambda, and negatively charged particles, measured at central rapidity in Pb-Pb collisions at top SPS energy. The data cover the 55% most central fraction of the inelastic cross section. The K^0_S and Lambda R_CP(p_T) are similar in shape to those measured at sqrt{s_NN} = 200 GeV at RHIC, though they are larger in absolute value. We have compared our K^0_S R_CP data to a theoretical calculation. The prediction overestimates the data at p_T \\approx 3-4 GeV/c, unless sizeable parton energy loss is included in the calculation.

NA57 Collaboration

2005-07-07T23:59:59.000Z

99

$J/?$ suppression in Pb+Pb collisions, a conventional description  

E-Print Network [OSTI]

We have analyzed the latest NA50 data on $J/\\psi$ suppression in Pb + Pb collisions. $J/\\psi$ production is assumed to be a two step process, (i) formation of $c\\bar{c}$ pair, which is accurately calculable in QCD and (ii) formation of $J/\\psi$ meson from the $c\\bar{c}$ pair, which can be conveniently parameterized. In a pA/AA collision, the as the $c\\bar{c}$ pair pass through the nuclear medium, it gain relative square momentum at the rate of $\\epsilon^2$ per unit path length. As a result, some of the $c\\bar{c}$ pairs can gain enough momentum to cross the threshold to become an open charm meson, leading to suppression in pA/AA collisions. The parameters of the model were fixed from experimental data on the total $J/\\psi$ cross section as a function of effective nuclear length. The model without any free parameter, give excellent description of NA50 data on $E_T$ dependence of $J/\\psi$ to Drell-Yan ratio. The model was applied to predict the $E_T$ dependence of $J/\\psi$ at RHIC energy. Much larger suppression of $J/\\psi$, in agreement with other model calculations are predicted.

A. K. Chaudhuri

2001-09-17T23:59:59.000Z

100

Jet quenching and neutral pion production in Au+Au collisions at RHIC  

E-Print Network [OSTI]

In the jet quenching model, we have analysed the PHENIX data on nuclear modification factor of $\\pi^0$, in Au+Au collisions at $\\sqrt{s}$=200 GeV, and extracted the initial gluon density of the medium produced. In jet quenching, partons lose energy in the medium, depending on the medium density as well as on the in-medium path length. Systematic analysis indicate that in most central (0-10% centrality) collisions, medium density is very large $dN_g/dy \\sim$ 2150. Medium density decreases exponentially as the collision centrality decreases and in very peripheral (70-92% centrality) collisions, $dN_g/dy \\sim$ 3. Initial energy density of the medium also decreases smoothly from $\\epsilon_0 \\sim$ 20 $GeV/fm^3$ in most central collisions to $\\epsilon_0 \\sim$ 3 $GeV/fm^3$ in most peripheral collisions. Very large $dN_g/dy$ or $\\epsilon_0$ indicate very dense matter formation in central Au+Au collisions.

A. K. Chaudhuri

2005-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
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101

A hybrid model for studying nuclear multifragmentation around Fermi energy domain: Case for central collision of Xe on Sn  

E-Print Network [OSTI]

Experimental data for central collisions of $^{129}$Xe on $^{119}$Sn at beam energies of (a) 32 MeV/nucleon, (b) 39 MeV/nucleon, (c) 45 MeV/nucleon and (d) 50 MeV/nucleon are compared with results calculated using a hybrid model. We use a transport model (BUU) to obtain the excitation energy per nucleon in the center of mass of the multifragmenting system. The canonical thermodynamic model is then used to determine the temperature which would lead to this excitation energy. With this temperature we use the canonical thermodynamic model to calculate various experimental data such as multiplicities of different composites, probability distribution of the largest cluster etc. Agreement with data establishes the validity of the model.

S. Mallik; G. Chaudhuri; S. Das Gupta

2015-03-17T23:59:59.000Z

102

A hybrid model for studying nuclear multifragmentation around Fermi energy domain: Case for central collision of Xe on Sn  

E-Print Network [OSTI]

Experimental data for central collisions of $^{129}$Xe on $^{119}$Sn at beam energies of (a) 32 MeV/nucleon, (b) 39 MeV/nucleon, (c) 45 MeV/nucleon and (d) 50 MeV/nucleon are compared with results calculated using a hybrid model. We use a transport model (BUU) to obtain the excitation energy per nucleon in the center of mass of the multifragmenting system. The canonical thermodynamic model is then used to determine the temperature which would lead to this excitation energy. With this temperature we use the canonical thermodynamic model to calculate various experimental data such as multiplicities of different composites, probability distribution of the largest cluster etc. Agreement with data establishes the validity of the model.

Mallik, S; Gupta, S Das

2015-01-01T23:59:59.000Z

103

Nuclear Science Division Annual Report 1984-85  

E-Print Network [OSTI]

M. Xcssi. and W. Wolf. Nuclear-Reaction-Time Studies of U +K° Produced in Relativistic Nuclear Collisions Phys. Lett.Momentum Distributions of Nuclear Fragments in im Collisions

Mahoney Editor, Jeannette

2010-01-01T23:59:59.000Z

104

NUCLEAR CHEMISTRY DIV. ANNUAL REPORT 1980-81  

E-Print Network [OSTI]

Polarization Phenomena in Nuclear Physics-1980, AIP Conf.Barrett and D.F. Jackson, Nuclear Sizes and Structure, (K Production in Relativistic Nuclear Collisions A. Shor, K.

Cerny, J.

2010-01-01T23:59:59.000Z

105

Observation of $D^0$ meson nuclear modifications in Au+Au collisions at $\\sqrt{s_{_{\\mathrm{NN}}}}$ = 200 GeV  

E-Print Network [OSTI]

We report the first measurement of charmed-hadron ($D^0$) production via the hadronic decay channel ($D^0\\rightarrow K^- + \\pi^+$) in Au+Au collisions at $\\sqrt{s_{_{\\mathrm{NN}}}}$ = 200\\,GeV with the STAR experiment. The charm production cross-section per nucleon-nucleon collision at mid-rapidity scales with the number of binary collisions, $N_{bin}$, from $p$+$p$ to central Au+Au collisions. The $D^0$ meson yields in central Au+Au collisions are strongly suppressed compared to those in $p$+$p$ scaled by $N_{bin}$, for transverse momenta $p_{T}>3$ GeV/$c$, demonstrating significant energy loss of charm quarks in the hot and dense medium. An enhancement at intermediate $p_{T}$ is also observed. Model calculations including strong charm-medium interactions and coalescence hadronization describe our measurements.

L. Adamczyk; J. K. Adkins; G. Agakishiev; M. M. Aggarwal; Z. Ahammed; I. Alekseev; J. Alford; C. D. Anson; A. Aparin; D. Arkhipkin; E. C. Aschenauer; G. S. Averichev; A. Banerjee; D. R. Beavis; R. Bellwied; A. Bhasin; A. K. Bhati; P. Bhattarai; H. Bichsel; J. Bielcik; J. Bielcikova; L. C. Bland; I. G. Bordyuzhin; W. Borowski; J. Bouchet; A. V. Brandin; S. G. Brovko; S. Bültmann; I. Bunzarov; T. P. Burton; J. Butterworth; H. Caines; M. Calderón de la Barca Sánchez; D. Cebra; R. Cendejas; M. C. Cervantes; P. Chaloupka; Z. Chang; S. Chattopadhyay; H. F. Chen; J. H. Chen; L. Chen; J. Cheng; M. Cherney; A. Chikanian; W. Christie; J. Chwastowski; M. J. M. Codrington; G. Contin; J. G. Cramer; H. J. Crawford; X. Cui; S. Das; A. Davila Leyva; L. C. De Silva; R. R. Debbe; T. G. Dedovich; J. Deng; A. A. Derevschikov; R. Derradi de Souza; S. Dhamija; B. di Ruzza; L. Didenko; C. Dilks; F. Ding; P. Djawotho; X. Dong; J. L. Drachenberg; J. E. Draper; C. M. Du; L. E. Dunkelberger; J. C. Dunlop; L. G. Efimov; J. Engelage; K. S. Engle; G. Eppley; L. Eun; O. Evdokimov; O. Eyser; R. Fatemi; S. Fazio; J. Fedorisin; P. Filip; E. Finch; Y. Fisyak; C. E. Flores; C. A. Gagliardi; D. R. Gangadharan; D. Garand; F. Geurts; A. Gibson; M. Girard; S. Gliske; L. Greiner; D. Grosnick; D. S. Gunarathne; Y. Guo; A. Gupta; S. Gupta; W. Guryn; B. Haag; A. Hamed; L-X. Han; R. Haque; J. W. Harris; S. Heppelmann; A. Hirsch; G. W. Hoffmann; D. J. Hofman; S. Horvat; B. Huang; H. Z. Huang; X. Huang; P. Huck; T. J. Humanic; G. Igo; W. W. Jacobs; H. Jang; E. G. Judd; S. Kabana; D. Kalinkin; K. Kang; K. Kauder; H. W. Ke; D. Keane; A. Kechechyan; A. Kesich; Z. H. Khan; D. P. Kikola; I. Kisel; A. Kisiel; D. D. Koetke; T. Kollegger; J. Konzer; I. Koralt; L. K. Kosarzewski; L. Kotchenda; A. F. Kraishan; P. Kravtsov; K. Krueger; I. Kulakov; L. Kumar; R. A. Kycia; M. A. C. Lamont; J. M. Landgraf; K. D. Landry; J. Lauret; A. Lebedev; R. Lednicky; J. H. Lee; M. J. LeVine; C. Li; W. Li; X. Li; X. Li; Y. Li; Z. M. Li; M. A. Lisa; F. Liu; T. Ljubicic; W. J. Llope; M. Lomnitz; R. S. Longacre; X. Luo; G. L. Ma; Y. G. Ma; D. M. M. D. Madagodagettige Don; D. P. Mahapatra; R. Majka; S. Margetis; C. Markert; H. Masui; H. S. Matis; D. McDonald; T. S. McShane; N. G. Minaev; S. Mioduszewski; B. Mohanty; M. M. Mondal; D. A. Morozov; M. K. Mustafa; B. K. Nandi; Md. Nasim; T. K. Nayak; J. M. Nelson; G. Nigmatkulov; L. V. Nogach; S. Y. Noh; J. Novak; S. B. Nurushev; G. Odyniec; A. Ogawa; K. Oh; A. Ohlson; V. Okorokov; E. W. Oldag; D. L. Olvitt Jr.; M. Pachr; B. S. Page; S. K. Pal; Y. X. Pan; Y. Pandit; Y. Panebratsev; T. Pawlak; B. Pawlik; H. Pei; C. Perkins; W. Peryt; P. Pile; M. Planinic; J. Pluta; N. Poljak; K. Poniatowska; J. Porter; A. M. Poskanzer; N. K. Pruthi; M. Przybycien; P. R. Pujahari; J. Putschke; H. Qiu; A. Quintero; S. Ramachandran; R. Raniwala; S. Raniwala; R. L. Ray; C. K. Riley; H. G. Ritter; J. B. Roberts; O. V. Rogachevskiy; J. L. Romero; J. F. Ross; A. Roy; L. Ruan; J. Rusnak; O. Rusnakova; N. R. Sahoo; P. K. Sahu; I. Sakrejda; S. Salur; J. Sandweiss; E. Sangaline; A. Sarkar; J. Schambach; R. P. Scharenberg; A. M. Schmah; W. B. Schmidke; N. Schmitz; J. Seger; P. Seyboth; N. Shah; E. Shahaliev; P. V. Shanmuganathan; M. Shao; B. Sharma; W. Q. Shen; S. S. Shi; Q. Y. Shou; E. P. Sichtermann; R. N. Singaraju; M. J. Skoby; D. Smirnov; N. Smirnov; D. Solanki; P. Sorensen; H. M. Spinka; B. Srivastava; T. D. S. Stanislaus; J. R. Stevens; R. Stock; M. Strikhanov; B. Stringfellow; M. Sumbera; X. Sun; X. M. Sun; Y. Sun; Z. Sun; B. Surrow; D. N. Svirida; T. J. M. Symons; M. A. Szelezniak; J. Takahashi; A. H. Tang; Z. Tang; T. Tarnowsky; J. H. Thomas; A. R. Timmins; D. Tlusty; M. Tokarev; S. Trentalange; R. E. Tribble; P. Tribedy; B. A. Trzeciak; O. D. Tsai; J. Turnau; T. Ullrich; D. G. Underwood; G. Van Buren; G. van Nieuwenhuizen; M. Vandenbroucke; J. A. Vanfossen, Jr.; R. Varma; G. M. S. Vasconcelos; A. N. Vasiliev; R. Vertesi; F. Videbćk; Y. P. Viyogi; S. Vokal; A. Vossen; M. Wada; F. Wang; G. Wang; H. Wang; J. S. Wang; X. L. Wang; Y. Wang; Y. Wang; G. Webb; J. C. Webb; G. D. Westfall; H. Wieman; S. W. Wissink; R. Witt; Y. F. Wu; Z. Xiao; W. Xie; K. Xin; H. Xu; J. Xu; N. Xu; Q. H. Xu; Y. Xu; Z. Xu; W. Yan; C. Yang; Y. Yang; Y. Yang; Z. Ye; P. Yepes; L. Yi; K. Yip; I-K. Yoo; N. Yu; Y. Zawisza; H. Zbroszczyk; W. Zha; J. B. Zhang; J. L. Zhang; S. Zhang; X. P. Zhang; Y. Zhang; Z. P. Zhang; F. Zhao; J. Zhao; C. Zhong; X. Zhu; Y. H. Zhu; Y. Zoulkarneeva; M. Zyzak

2014-09-09T23:59:59.000Z

106

anneau de collisions d'orsay: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the nuclear Caldern de la Barca Snchez, Manuel 288 Elementary Collisions with HADES Nuclear Experiment (arXiv) Summary: The "High Acceptance DiElectron Spectrometer"...

107

Simulation of collision cascades and thermal spikes in ceramics...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

formed and mainly isolated Frenkel pairs are produced. Citation: Devanathan R, and WJ Weber.2010."Simulation of collision cascades and thermal spikes in ceramics."Nuclear...

108

atomic collision cascades: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

implications. Leszek Motyka; Mariusz Sadzikowski 1999-12-04 2 Parton Cascades in High Energy Nuclear Collisions Nuclear Theory (arXiv) Summary: This is a review of the parton...

109

Probing nuclear matter with jet conversions  

E-Print Network [OSTI]

T > 5 GeV/c.RAA measures the ratio of yields in nuclear collisions (A+A) vs nucleon-nucleon collisions (N+N ) at the same energy scaled with the appropriate number of binary collisions. High-pT hadrons above 5 GeV/c inA+A collisions are believed...

Liu, W.; Fries, Rainer J.

2008-01-01T23:59:59.000Z

110

Mean field and collisions in hot nuclei  

SciTech Connect (OSTI)

Collisions between heavy nuclei produce nuclear matter of high density and excitation. Brueckner methods are used to calculate the momentum and temperature dependent mean field for nucleons propagating through nuclear matter during these collisions. The mean field is complex and the imaginary part is related to the ''two-body'' collision, while the real part relates to ''one-body'' collisions. A potential model for the N-N interactions is avoided by calculating the Reaction matrix directly from the T-matrix (i.e., N-N phase shifts) using a version of Brueckner theory previously published by the author. Results are presented for nuclear matter at normal and twice normal density and for temperatures up to 50 MeV. 23 refs., 7 figs.

K /umlt o/hler, H.S.

1989-06-01T23:59:59.000Z

111

Improving Collision Induced Dissociation (CID), High Energy Collision...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Collision Induced Dissociation (CID), High Energy Collision Dissociation (HCD), and Electron Transfer Dissociation Improving Collision Induced Dissociation (CID), High Energy...

112

Forward Lambda production and nuclear stopping power in d+Au collisions at root s(NN)=200 GeV  

E-Print Network [OSTI]

We report the measurement of Lambda and (Lambda) over bar yields and inverse slope parameters in d+Au collisions at root s(NN)=200 GeV at forward and backward rapidities (y=+/- 2.75), using data from the STAR forward time projection chambers...

Abelev, B. I.; Aggarwal, M. M.; Ahammed, Z.; Anderson, B. D.; Arkhipkin, D.; Averichev, G. S.; Bai, Y.; Balewski, J.; Barannikova, O.; Barnby, L. S.; Baudot, J.; Baumgart, S.; Belaga, V. V.; Bellingeri-Laurikainen, A.; Bellwied, R.; Benedosso, F.; Betts, R. R.; Bhardwaj, S.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Blyth, S. -L; Bombara, M.; Bonner, B. E.; Botje, M.; Bouchet, J.; Brandin, A. V.; Bravar, A.; Burton, T. P.; Bystersky, M.; Cai, X. Z.; Caines, H.; Sanchez, M. Calderon de la Barca; Callner, J.; Catu, O.; Cebra, D.; Cervantes, M. C.; Chajecki, Z.; Chaloupka, P.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chung, S. U.; Clarke, R. F.; Codrington, M. J. M.; Coffin, J. P.; Cormier, T. M.; Cosentino, M. R.; Cramer, J. G.; Crawford, H. J.; Das, D.; Dash, S.; Daugherity, M.; de Moura, M. M.; Dedovich, T. G.; DePhillips, M.; Derevschikov, A. A.; Didenko, L.; Dietel, T.; Djawotho, P.; Dogra, S. M.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, F.; Dunin, V. B.; Dunlop, J. C.; Mazumdar, M. R. Dutta; Eckardt, V.; Edwards, W. R.; Efimov, L. G.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Fachini, P.; Fatemi, R.; Fedorisin, J.; Feng, A.; Filip, P.; Finch, E.; Fine, V.; Fisyak, Y.; Fu, J.; Gagliardi, Carl A.; Gaillard, L.; Ganti, M. S.; Garcia-Solis, E.; Ghazikhanian, V.; Ghosh, P.; Gorbunov, Y. N.; Gos, H.; Grebenyuk, O.; Grosnick, D.; Grube, B.; Guertin, S. M.; Guimaraes, K. S. F. F.; Gupta, N.; Haag, B.; Hallman, T. J.; Hamed, A.; Harris, J. W.; He, W.; Heinz, M.; Henry, T. W.; Heppelmann, S.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffman, A. M.; Hoffmann, G. W.; Hofman, D. J.; Hollis, R. S.; Horner, M. J.; Huang, H. Z.; Hughes, E. W.; Humanic, T. J.; Igo, G.; Iordanova, A.; Jacobs, P.; Jacobs, W. W.; Jakl, P.; Jia, F.; Jones, P. G.; Judd, E. G.; Kabana, S.; Kang, K.; Kapitan, J.; Kaplan, M.; Keane, D.; Kechechyan, A.; Kettler, D.; Khodyrev, V. Yu; Kiryluk, J.; Kisiel, A.; Kislov, E. M.; Klein, S. R.; Knospe, A. G.; Kocoloski, A.; Koetke, D. D.; Kollegger, T.; Kopytine, M.; Kotchenda, L.; Kouchpil, V.; Kowalik, K. L.; Kravtsov, P.; Kravtsov, V. I.; Krueger, K.; Kuhn, C.; Kulikov, A. I.; Kumar, A.; Kurnadi, P.; Kuznetsov, A. A.; Lamont, M. A. C.; Landgraf, J. M.; Lange, S.; LaPointe, S.; Laue, F.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, C. -H; Lehocka, S.; LeVine, M. J.; Li, C.; Li, Q.; Li, Y.; Lin, G.; Lin, X.; Lindenbaum, S. J.; Lisa, M. A.; Liu, F.; Liu, H.; Liu, J.; Liu, L.; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Love, W. A.; Lu, Y.; Ludlam, T.; Lynn, D.; Ma, G. L.; Ma, J. G.; Ma, Y. G.; Mahapatra, D. P.; Majka, R.; Mangotra, L. K.; Manweiler, R.; Margetis, S.; Markert, C.; Martin, L.; Matis, H. S.; Matulenko, Yu A.; McClain, C. J.; McShane, T. S.; Melnick, Yu; Meschanin, A.; Millane, J.; Miller, M. L.; Minaev, N. G.; Mioduszewski, Saskia; Mischke, A.; Mitchell, J.; Mohanty, B.; Morozov, D. A.; Munhoz, M. G.; Nandi, B. K.; Nattrass, C.; Nayak, T. K.; Nelson, J. M.; Nepali, C.; Netrakanti, P. K.; Nogach, L. V.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Okorokov, V.; Oldenburg, M.; Olson, D.; Pachr, M.; Pal, S. K.; Panebratsev, Y.; Pavlinov, A. I.; Pawlak, T.; Peitzmann, T.; Perevoztchikov, V.; Perkins, C.; Peryt, W.; Phatak, S. C.; Planinic, M.; Pluta, J.; Poljak, N.; Porile, N.; Poskanzer, A. M.; Potekhin, M.; Potrebenikova, E.; Potukuchi, B. V. K. S.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Putschke, J.; Qattan, I. A.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Relyea, D.; Ridiger, A.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Rose, A.; Roy, C.; Ruan, L.; Russcher, M. J.; Sahoo, R.; Sakrejda, I.; Sakuma, T.; Salur, S.; Sandweiss, J.; Sarsour, M.; Sazhin, P. S.; Schambach, J.; Scharenberg, R. P.; Schmitz, N.; Seger, J.; Selyuzhenkov, I.; Seyboth, P.; Shabetai, A.; Shahaliev, E.; Shao, M.; Sharma, M.; Shen, W. Q.; Shimanskiy, S. S.; Sichtermann, E. P.; Simon, F.; Singaraju, R. N.; Smirnov, N.; Snellings, R.; Sorensen, P.; Sowinski, J.; Speltz, J.; Spinka, H. M.; Srivastava, B.; Stadnik, A.; Stanislaus, T. D. S.; Staszak, D.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Subba, N. L.; Sumbera, M.; Sun, X. M.; Sun, Z.; Surrow, B.; Symons, T. J. M.; De Toledo, A. Szanto; Takahashi, J.; Tang, A. H.; Tarnowsky, T.; Thomas, J. H.; Timmins, A. R.; Timoshenko, S.; Tokarev, M.; Trainor, T. A.; Trentalange, S.; Tribble, Robert E.; Tsai, O. D.; Ulery, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; Van der Kolk, N.; Van Leeuwen, M.; Molen, A. M. Vander; Varma, R.; Vasilevski, I. M.; Vasiliev, A. N.; Vernet, R.; Vigdor, S. E.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Wada, M.

2007-01-01T23:59:59.000Z

113

Editorial: Redefining Length  

SciTech Connect (OSTI)

Technological changes have moved publishing to electronic-first publication where the print version has been relegated to simply another display mode. Distribution in HTML and EPUB formats, for example, changes the reading environment and reduces the need for strict pagination. Therefore, in an effort to streamline the calculation of length, the APS journals will no longer use the printed page as the determining factor for length. Instead the journals will now use word counts (or word equivalents for tables, figures, and equations) to establish length; for details please see http://publish.aps.org/authors/length-guide. The title, byline, abstract, acknowledgment, and references will not be included in these counts allowing authors the freedom to appropriately credit coworkers, funding sources, and the previous literature, bringing all relevant references to the attention of readers. This new method for determining length will be easier for authors to calculate in advance, and lead to fewer length-associated revisions in proof, yet still retain the quality of concise communication that is a virtue of short papers.

Sprouse, Gene D. [American Physical Society (United States)

2011-07-15T23:59:59.000Z

114

In-medium NN cross sections determined from the nuclear stopping and collective flow in heavy-ion collisions at intermediate energies  

SciTech Connect (OSTI)

In-medium nucleon-nucleon scattering cross sections are explored by comparing results of quantum molecular dynamics simulations to data on stopping and on elliptic and directed flow in intermediate-energy heavy-ion collisions. The comparison points to in-medium cross sections which are suppressed at low energies but not at higher energies. Positive correlations are found between the degree of stopping and the magnitudes of elliptic and directed flows.

Zhang Yingxun [China Institute of Atomic Energy, P.O. Box 275 (18), Beijing 102413 (China); Li Zhuxia [China Institute of Atomic Energy, P.O. Box 275 (18), Beijing 102413 (China); Center of Theoretical Nuclear Physics, National Laboratory of Lanzhou Heavy Ion Accelerator, Lanzhou 730000 (China); Institute of Theoretical Physics, Chinese Academic of Science, Beijing 100080 (China); Danielewicz, Pawel [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)

2007-03-15T23:59:59.000Z

115

Scattering lengths for collisions between sodium and potassium atoms  

E-Print Network [OSTI]

Venturi,V. Jamieson,M.J. Cote,R. Journal of Physics B: Atomic, Molecular and Optical Physics, Vol. 34 pp 4339-4347

Venturi, V.

116

Scattering lengths for collisions of hydrogen and deuterium atoms  

E-Print Network [OSTI]

Chu,X. Jamieson,M.J. Dalgarno,A. Journal of Physics B: Atomic, Molecular and Optical Physics, Vol. 36 pp L415-L418

Chu, X.; Jamieson, M.J.

117

Rapidity and transverse-momentum dependence of the inclusive J/$\\mathbf{\\psi}$ nuclear modification factor in p-Pb collisions at $\\mathbf{\\sqrt{\\textit{s}_{NN}}}=5.02$ TeV  

E-Print Network [OSTI]

We have studied the transverse-momentum ($p_{\\rm T}$) dependence of the inclusive J/$\\psi$ production in p-Pb collisions at $\\sqrt{s_{\\rm NN}} = 5.02$ TeV, in three center-of-mass rapidity ($y_{\\rm cms}$) regions, down to zero $p_{\\rm T}$. Results in the forward and backward rapidity ranges ($2.03 < y_{\\rm cms} < 3.53$ and $-4.46 nuclear modification factor are presented for each of the rapidity intervals, as well as the J/$\\psi$ mean $p_{\\rm T}$ values. Forward and mid-rapidity results show a suppression of the J/$\\psi$ yield, with respect to pp collisions, which decreases with increasing $p_{\\rm T}$. At backward rapidity no significant J/$\\psi$ suppression is observed. Theoretical models including a combinatio...

Adam, Jaroslav; Aggarwal, Madan Mohan; Aglieri Rinella, Gianluca; Agnello, Michelangelo; Agrawal, Neelima; Ahammed, Zubayer; Ahmed, Ijaz; Ahn, Sang Un; Aimo, Ilaria; Aiola, Salvatore; Ajaz, Muhammad; Akindinov, Alexander; Alam, Sk Noor; Aleksandrov, Dmitry; Alessandro, Bruno; Alexandre, Didier; Alfaro Molina, Jose Ruben; Alici, Andrea; Alkin, Anton; Alme, Johan; Alt, Torsten; Altinpinar, Sedat; Altsybeev, Igor; Alves Garcia Prado, Caio; Andrei, Cristian; Andronic, Anton; Anguelov, Venelin; Anielski, Jonas; Anticic, Tome; Antinori, Federico; Antonioli, Pietro; Aphecetche, Laurent Bernard; Appelshaeuser, Harald; Arcelli, Silvia; Armesto Perez, Nestor; Arnaldi, Roberta; Aronsson, Tomas; Arsene, Ionut Cristian; Arslandok, Mesut; Augustinus, Andre; Averbeck, Ralf Peter; Azmi, Mohd Danish; Bach, Matthias Jakob; Badala, Angela; Baek, Yong Wook; Bagnasco, Stefano; Bailhache, Raphaelle Marie; Bala, Renu; Baldisseri, Alberto; Baltasar Dos Santos Pedrosa, Fernando; Baral, Rama Chandra; Barbano, Anastasia Maria; Barbera, Roberto; Barile, Francesco; Barnafoldi, Gergely Gabor; Barnby, Lee Stuart; Ramillien Barret, Valerie; Bartalini, Paolo; Bartke, Jerzy Gustaw; Bartsch, Esther; Basile, Maurizio; Bastid, Nicole; Basu, Sumit; Bathen, Bastian; Batigne, Guillaume; Batista Camejo, Arianna; Batyunya, Boris; Batzing, Paul Christoph; Bearden, Ian Gardner; Beck, Hans; Bedda, Cristina; Behera, Nirbhay Kumar; Belikov, Iouri; Bellini, Francesca; Bello Martinez, Hector; Bellwied, Rene; Belmont Iii, Ronald John; Belmont Moreno, Ernesto; Belyaev, Vladimir; Bencedi, Gyula; Beole, Stefania; Berceanu, Ionela; Bercuci, Alexandru; Berdnikov, Yaroslav; Berenyi, Daniel; Bertens, Redmer Alexander; Berzano, Dario; Betev, Latchezar; Bhasin, Anju; Bhat, Inayat Rasool; Bhati, Ashok Kumar; Bhattacharjee, Buddhadeb; Bhom, Jihyun; Bianchi, Livio; Bianchi, Nicola; Bianchin, Chiara; Bielcik, Jaroslav; Bielcikova, Jana; Bilandzic, Ante; Biswas, Saikat; Bjelogrlic, Sandro; Blanco, Fernando; Blau, Dmitry; Blume, Christoph; Bock, Friederike; Bogdanov, Alexey; Boggild, Hans; Boldizsar, Laszlo; Bombara, Marek; Book, Julian Heinz; Borel, Herve; Borissov, Alexander; Borri, Marcello; Bossu, Francesco; Botje, Michiel; Botta, Elena; Boettger, Stefan; Braun-Munzinger, Peter; Bregant, Marco; Breitner, Timo Gunther; Broker, Theo Alexander; Browning, Tyler Allen; Broz, Michal; Brucken, Erik Jens; Bruna, Elena; Bruno, Giuseppe Eugenio; Budnikov, Dmitry; Buesching, Henner; Bufalino, Stefania; Buncic, Predrag; Busch, Oliver; Buthelezi, Edith Zinhle; Buxton, Jesse Thomas; Caffarri, Davide; Cai, Xu; Caines, Helen Louise; Calero Diaz, Liliet; Caliva, Alberto; Calvo Villar, Ernesto; Camerini, Paolo; Carena, Francesco; Carena, Wisla; Castillo Castellanos, Javier Ernesto; Castro, Andrew John; Casula, Ester Anna Rita; Cavicchioli, Costanza; Ceballos Sanchez, Cesar; Cepila, Jan; Cerello, Piergiorgio; Chang, Beomsu; Chapeland, Sylvain; Chartier, Marielle; Charvet, Jean-Luc Fernand; Chattopadhyay, Subhasis; Chattopadhyay, Sukalyan; Chelnokov, Volodymyr; Cherney, Michael Gerard; Cheshkov, Cvetan Valeriev; Cheynis, Brigitte; Chibante Barroso, Vasco Miguel; Dobrigkeit Chinellato, David; Chochula, Peter; Choi, Kyungeon; Chojnacki, Marek; Choudhury, Subikash; Christakoglou, Panagiotis; Christensen, Christian Holm; Christiansen, Peter; Chujo, Tatsuya; Chung, Suh-Urk; Cicalo, Corrado; Cifarelli, Luisa; Cindolo, Federico; Cleymans, Jean Willy Andre; Colamaria, Fabio Filippo; Colella, Domenico; Collu, Alberto; Colocci, Manuel; Conesa Balbastre, Gustavo; Conesa Del Valle, Zaida; Connors, Megan Elizabeth; Contreras Nuno, Jesus Guillermo; Cormier, Thomas Michael; Corrales Morales, Yasser; Cortes Maldonado, Ismael; Cortese, Pietro; Cosentino, Mauro Rogerio; Costa, Filippo; Crochet, Philippe; Cruz Albino, Rigoberto; Cuautle Flores, Eleazar; Cunqueiro Mendez, Leticia; Dahms, Torsten; Dainese, Andrea; Danu, Andrea; Das, Debasish; Das, Indranil; Das, Supriya; Dash, Ajay Kumar; Dash, Sadhana; De, Sudipan; De Caro, Annalisa; De Cataldo, Giacinto; De Cuveland, Jan; De Falco, Alessandro; De Gruttola, Daniele; De Marco, Nora; De Pasquale, Salvatore; Deisting, Alexander; Deloff, Andrzej; Denes, Ervin Sandor; D'Erasmo, Ginevra; Di Bari, Domenico; Di Mauro, Antonio; Di Nezza, Pasquale; Diaz Corchero, Miguel Angel; Dietel, Thomas; Dillenseger, Pascal; Divia, Roberto; Djuvsland, Oeystein; Dobrin, Alexandru Florin; Dobrowolski, Tadeusz Antoni; Domenicis Gimenez, Diogenes; Donigus, Benjamin; Dordic, Olja; Dubey, Anand Kumar; Dubla, Andrea; Ducroux, Laurent

2015-01-01T23:59:59.000Z

118

Planck-Length Phenomenology  

E-Print Network [OSTI]

This author's recent proposal of interferometric tests of Planck-scale-related properties of space-time is here revisited from a strictly phenomenological viewpoint. The results announced previously are rederived using elementary dimensional considerations. The dimensional analysis is then extended to the other two classes of experiments (observations of neutral kaons at particle accelerators and observations of the gamma rays we detect from distant astrophysical sources) which have been recently considered as opportunities to explore "foamy" properties of space-time. The emerging picture suggests that there is an objective and intuitive way to connect the sensitivities of these three experiments with the Planck length. While in previous studies the emphasis was always on some quantum-gravity scenario and the analysis was always primarily aimed at showing that the chosen scenario would leave a trace in a certain class of doable experiments, the analysis here reported takes as starting point the experiments and, by relating in a direct quantitative way the sensitivities to the Planck length, provides a model-independent description of the status of Planck-length phenomenology.

Giovanni Amelino-Camelia

2000-08-04T23:59:59.000Z

119

New results on nuclear dependence of J/psi and psi' production in 450 GeV pA collisions  

E-Print Network [OSTI]

To understand the reliability of the charmonia suppression as a signature of the Quark-Gluon Plasma formation in nucleus-nucleus collisions it is important first to understand the details of the production of J/psi and psi' in pA interactions and the difference in the suppression of these two states. This report presents the results of the study by the NA50 collaboration of the J/psi and psi' production in pA interactions at 450 GeV beam energy and its dependence on rapidity. It is shown that the psi' suffers more suppression than the J/psi, which is consistent with a similar observation made at 800 GeV beam energy by the E866/NuSea collaboration.

R. Shahoyan

2002-07-03T23:59:59.000Z

120

Quantum microscopic approach to low-energy heavy ion collisions  

E-Print Network [OSTI]

of nuclear reactions at low energy where quantum effects play a significant role is an important challenge of nuclear physics. The interplay between nuclear structure and reaction mechanisms is crucial at energiesQuantum microscopic approach to low-energy heavy ion collisions C´edric Simenel1,2, Aditya Wakhle2

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121

Measurements of Dihadron Correlations Relative to the Event Plane in Au+Au Collisions at $\\sqrt{s_{NN}}=200$ GeV  

E-Print Network [OSTI]

Dihadron azimuthal correlations containing a high transverse momentum ($\\pt$) trigger particle are sensitive to the properties of the nuclear medium created at RHIC through the strong interactions occurring between the traversing parton and the medium, i.e. jet-quenching. Previous measurements revealed a strong modification to dihadron azimuthal correlations in Au+Au collisions with respect to \\pp\\ and \\dAu\\ collisions. The modification increases with the collision centrality, suggesting a path-length dependence to the jet-quenching effect. This paper reports STAR measurements of dihadron azimuthal correlations in mid-central (20-60\\%) Au+Au collisions at $\\snn=200$~GeV as a function of the trigger particle's azimuthal angle relative to the event plane, $\\phis=|\\phit-\\psiEP|$. The azimuthal correlation is studied as a function of both the trigger and associated particle $\\pt$. The subtractions of the combinatorial background and anisotropic flow, assuming Zero Yield At Minimum (\\zyam), are described. The away-side correlation is strongly modified, and the modification varies with $\\phis$, which is expected to be related to the path-length that the away-side parton traverses. The pseudo-rapidity ($\\deta$) dependence of the near-side correlation, sensitive to long range $\\deta$ correlations (the ridge), is also investigated. The ridge and jet-like components of the near-side correlation are studied as a function of $\\phis$. The ridge appears to drop with increasing $\\phis$ while the jet-like component remains approximately constant. ...

H. Agakishiev; M. M. Aggarwal; Z. Ahammed; A. V. Alakhverdyants; I. Alekseev; J. Alford; B. D. Anderson; C. D. Anson; D. Arkhipkin; G. S. Averichev; J. Balewski; D. R. Beavis; N. K. Behera; R. Bellwied; M. J. Betancourt; R. R. Betts; A. Bhasin; A. K. Bhati; H. Bichsel; J. Bielcik; J. Bielcikova; B. Biritz; L. C. Bland; W. Borowski; J. Bouchet; E. Braidot; A. V. Brandin; A. Bridgeman; S. G. Brovko; E. Bruna; S. Bueltmann; I. Bunzarov; T. P. Burton; X. Z. Cai; H. Caines; M. Calderón de la Barca Sánchez; D. Cebra; R. Cendejas; M. C. Cervantes; Z. Chajecki; P. Chaloupka; S. Chattopadhyay; H. F. Chen; J. H. Chen; J. Y. Chen; L. Chen; J. Cheng; M. Cherney; A. Chikanian; K. E. Choi; W. Christie; P. Chung; M. J. M. Codrington; R. Corliss; J. G. Cramer; H. J. Crawford; S. Dash; A. Davila Leyva; L. C. De Silva; R. R. Debbe; T. G. Dedovich; A. A. Derevschikov; R. Derradi de Souza; L. Didenko; P. Djawotho; S. M. Dogra; X. Dong; J. L. Drachenberg; J. E. Draper; J. C. Dunlop; L. G. Efimov; M. Elnimr; J. Engelage; G. Eppley; M. Estienne; L. Eun; O. Evdokimov; R. Fatemi; J. Fedorisin; R. G. Fersch; P. Filip; E. Finch; V. Fine; Y. Fisyak; C. A. Gagliardi; D. R. Gangadharan; A. Geromitsos; F. Geurts; P. Ghosh; Y. N. Gorbunov; A. Gordon; O. Grebenyuk; D. Grosnick; S. M. Guertin; A. Gupta; W. Guryn; B. Haag; O. Hajkova; A. Hamed; L-X. Han; J. W. Harris; J. P. Hays-Wehle; M. Heinz; S. Heppelmann; A. Hirsch; E. Hjort; G. W. Hoffmann; D. J. Hofman; B. Huang; H. Z. Huang; T. J. Humanic; L. Huo; G. Igo; P. Jacobs; W. W. Jacobs; C. Jena; F. Jin; J. Joseph; E. G. Judd; S. Kabana; K. Kang; J. Kapitan; K. Kauder; H. Ke; D. Keane; A. Kechechyan; D. Kettler; D. P. Kikola; J. Kiryluk; A. Kisiel; V. Kizka; A. G. Knospe; D. D. Koetke; T. Kollegger; J. Konzer; I. Koralt; L. Koroleva; W. Korsch; L. Kotchenda; V. Kouchpil; P. Kravtsov; K. Krueger; M. Krus; L. Kumar; P. Kurnadi; M. A. C. Lamont; J. M. Landgraf; S. LaPointe; J. Lauret; A. Lebedev; R. Lednicky; J. H. Lee; W. Leight; M. J. LeVine; C. Li; L. Li; N. Li; W. Li; X. Li; X. Li; Y. Li; Z. M. Li; M. A. Lisa; F. Liu; H. Liu; J. Liu; T. Ljubicic; W. J. Llope; R. S. Longacre; W. A. Love; Y. Lu; E. V. Lukashov; X. Luo; G. L. Ma; Y. G. Ma; D. P. Mahapatra; R. Majka; O. I. Mall; L. K. Mangotra; R. Manweiler; S. Margetis; C. Markert; H. Masui; H. S. Matis; Yu. A. Matulenko; D. McDonald; T. S. McShane; A. Meschanin; R. Milner; N. G. Minaev; S. Mioduszewski; A. Mischke; M. K. Mitrovski; B. Mohanty; M. M. Mondal; B. Morozov; D. A. Morozov; M. G. Munhoz; M. Naglis; B. K. Nandi; T. K. Nayak; P. K. Netrakanti; L. V. Nogach; S. B. Nurushev; G. Odyniec; A. Ogawa; Oh; Ohlson; V. Okorokov; E. W. Oldag; D. Olson; M. Pachr; B. S. Page; S. K. Pal; Y. Pandit; Y. Panebratsev; T. Pawlak; H. Pei; T. Peitzmann; C. Perkins; W. Peryt; S. C. Phatak; P. Pile; M. Planinic; M. A. Ploskon; J. Pluta; D. Plyku; N. Poljak; A. M. Poskanzer; B. V. K. S. Potukuchi; C. B. Powell; D. Prindle; C. Pruneau; N. K. Pruthi; P. R. Pujahari; J. Putschke; H. Qiu; R. Raniwala; S. Raniwala; R. L. Ray; R. Redwine; R. Reed; H. G. Ritter; J. B. Roberts; O. V. Rogachevskiy; J. L. Romero; A. Rose; L. Ruan; J. Rusnak; N. R. Sahoo; S. Sakai; I. Sakrejda; T. Sakuma; S. Salur; J. Sandweiss; E. Sangaline; A. Sarkar; J. Schambach; R. P. Scharenberg; A. M. Schmah; T. R. Schuster; J. Seele; J. Seger; I. Selyuzhenkov; P. Seyboth; E. Shahaliev; M. Shao; M. Sharma; S. S. Shi; Q. Y. Shou; E. P. Sichtermann; F. Simon; R. N. Singaraju; M. J. Skoby; N. Smirnov; H. M. Spinka; B. Srivastava; T. D. S. Stanislaus; D. Staszak; S. G. Steadman; J. R. Stevens; R. Stock; M. Strikhanov; B. Stringfellow; A. A. P. Suaide; M. C. Suarez; N. L. Subba; M. Sumbera; X. M. Sun; Y. Sun; Z. Sun; B. Surrow; D. N. Svirida; T. J. M. Symons; A. Szanto de Toledo; J. Takahashi; A. H. Tang; Z. Tang; L. H. Tarini; T. Tarnowsky; D. Thein; J. H. Thomas; J. Tian; A. R. Timmins; D. Tlusty; M. Tokarev; V. N. Tram; S. Trentalange; R. E. Tribble; Tribedy; O. D. Tsai; T. Ullrich; D. G. Underwood; G. Van Buren; G. van Nieuwenhuizen; J. A. Vanfossen, Jr.; R. Varma; G. M. S. Vasconcelos; A. N. Vasiliev; F. Videbćk; Y. P. Viyogi; S. Vokal; M. Wada; M. Walker; F. Wang; G. Wang; H. Wang; J. S. Wang; Q. Wang; X. L. Wang; Y. Wang; G. Webb; J. C. Webb; G. D. Westfall; C. Whitten Jr.; H. Wieman; S. W. Wissink; R. Witt; W. Witzke; Y. F. Wu; Xiao; W. Xie; H. Xu; N. Xu; Q. H. Xu; W. Xu; Y. Xu; Z. Xu; L. Xue; Y. Yang; P. Yepes; K. Yip; I-K. Yoo; M. Zawisza; H. Zbroszczyk; W. Zhan; J. B. Zhang; S. Zhang; W. M. Zhang; X. P. Zhang; Y. Zhang; Z. P. Zhang; J. Zhao; C. Zhong; W. Zhou; X. Zhu; Y. H. Zhu; R. Zoulkarneev; Y. Zoulkarneeva

2013-05-16T23:59:59.000Z

122

Some Intensive and Extensive Quantities in High-Energy Collisions  

E-Print Network [OSTI]

We review the evolution of some statistical and thermodynamical quantities measured in difference sizes of high-energy collisions at different energies. We differentiate between intensive and extensive quantities and discuss the importance of their distinguishability in characterizing possible critical phenomena of nuclear collisions at various energies with different initial conditions.

A. Tawfik

2013-10-02T23:59:59.000Z

123

Energy-Length Rule  

E-Print Network [OSTI]

Lorentz ordering (causality) implies the following rule: for any given energy p0 of a system there is a certain interval c0 on x0 so that their product is the Lorentz ordering constant L It means p0c0 = L. The constant L=hc. Hence Planck constant h in a similar way as c are both consequences of Lorentz metric. The basic ideas are: 1. Lorentz metric implies that x0 must represent a length like the other components of x in X 2. The dual metric space X* is well defined since the Lorentz metric tensor is not singular. The components of the vectors p in X*are interpreted as representing energy. The properties of the physical systems that are direct consequences of the detailed structure of X and X*, and so expressed through the Lorentz Limit L are presented.

Alexandru C Mihul; Eleonora A Mihul

2006-08-25T23:59:59.000Z

124

Collisions of Nuclei: New Ideas for Hard  

E-Print Network [OSTI]

cosmic rays impacting on planetary objects. In the lab: high energy nuclear collisions! BNL RHIC Au environment Summary [With W. Liu, Phys.Rev.C77:054902,2008 Phys.Rev.C78:037902,2008] [In progress, with R Pb+Pb @ s = 5.5 TeV First run 2010 ? ???? #12;TIFR 2009 7Rainer Fries Sketch of a HE Nuclear

125

First Order Phase Transition in Intermediate Energy Heavy Ion Collisions  

E-Print Network [OSTI]

We model the disassembly of an excited nuclear system formed as a result of a heavy ion collision. We find that, as the beam energy in central collisions in varied, the dissociating system crosses a liquid-gas coexistence curve, resulting in a first-order phase transition. Accessible experimental signatures are identified: a peak in specific heat, a power-law yield for composites, and a maximum in the second moment of the yield distribution.

J. Pan; S. Das Gupta; M. Grant

1997-11-01T23:59:59.000Z

126

agip nucleare: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

shadowing in high-energy nuclear collisions are presented. N. Armesto 2006-07-05 3 Nuclear Power CiteSeer Summary: this report does not contain recommendations or solutions...

127

NEUTRON EMISSION IN RELATIVISTIC NUCLEAR COLLISIONS  

E-Print Network [OSTI]

Figure Captions Figure l. Neutron-to-proton ratio at 30° labapparent anomalies in the neutron-to-proton fragment ratio.3 proton data. Figure 2. Neutron-to-proton ratio R 1 , Solid

Stevenson, J.D.

2013-01-01T23:59:59.000Z

128

Multiphase transport model for relativistic nuclear collisions  

E-Print Network [OSTI]

~1995!. @3# S.H. Kahana, D.E. Kahana, Y. Pang, and T.J. Schlagel, Ann. Phys. ~San Diego! 46, 31 ~1996!. @4# W. Cassing and E.L. Bratkovskaya, Phys. Rep. 308, 65 ~1999!. @5# H. Sorge, Phys. Rev. C 52, 3291 ~1995!. @6# S.A. Bass et al., Prog. Part.... Shuryak, Phys. Rev. Lett. 68, 3270 ~1992!. @19# B. Zhang, C.M. Ko, B.A. Li, and Z. Lin, in Proceedings of Relativistic Heavy Ion Mini-symposium in APS Centennial Meeting. @20# M. Gyulassy, Y. Pang, and B. Zhang, Nucl. Phys. A626, 999 ~1997!. @21# NA...

Zhang, B.; Ko, Che Ming; Li, Ba; Lin, ZW.

2000-01-01T23:59:59.000Z

129

Neutron transport analysis for nuclear reactor design  

DOE Patents [OSTI]

Replacing regular mesh-dependent ray tracing modules in a collision/transfer probability (CTP) code with a ray tracing module based upon combinatorial geometry of a modified geometrical module (GMC) provides a general geometry transfer theory code in two dimensions (2D) for analyzing nuclear reactor design and control. The primary modification of the GMC module involves generation of a fixed inner frame and a rotating outer frame, where the inner frame contains all reactor regions of interest, e.g., part of a reactor assembly, an assembly, or several assemblies, and the outer frame, with a set of parallel equidistant rays (lines) attached to it, rotates around the inner frame. The modified GMC module allows for determining for each parallel ray (line), the intersections with zone boundaries, the path length between the intersections, the total number of zones on a track, the zone and medium numbers, and the intersections with the outer surface, which parameters may be used in the CTP code to calculate collision/transfer probability and cross-section values.

Vujic, Jasmina L. (Lisle, IL)

1993-01-01T23:59:59.000Z

130

Neutron transport analysis for nuclear reactor design  

DOE Patents [OSTI]

Replacing regular mesh-dependent ray tracing modules in a collision/transfer probability (CTP) code with a ray tracing module based upon combinatorial geometry of a modified geometrical module (GMC) provides a general geometry transfer theory code in two dimensions (2D) for analyzing nuclear reactor design and control. The primary modification of the GMC module involves generation of a fixed inner frame and a rotating outer frame, where the inner frame contains all reactor regions of interest, e.g., part of a reactor assembly, an assembly, or several assemblies, and the outer frame, with a set of parallel equidistant rays (lines) attached to it, rotates around the inner frame. The modified GMC module allows for determining for each parallel ray (line), the intersections with zone boundaries, the path length between the intersections, the total number of zones on a track, the zone and medium numbers, and the intersections with the outer surface, which parameters may be used in the CTP code to calculate collision/transfer probability and cross-section values. 28 figures.

Vujic, J.L.

1993-11-30T23:59:59.000Z

131

Continuously variable focal length lens  

DOE Patents [OSTI]

A material preferably in crystal form having a low atomic number such as beryllium (Z=4) provides for the focusing of x-rays in a continuously variable manner. The material is provided with plural spaced curvilinear, optically matched slots and/or recesses through which an x-ray beam is directed. The focal length of the material may be decreased or increased by increasing or decreasing, respectively, the number of slots (or recesses) through which the x-ray beam is directed, while fine tuning of the focal length is accomplished by rotation of the material so as to change the path length of the x-ray beam through the aligned cylindrical slows. X-ray analysis of a fixed point in a solid material may be performed by scanning the energy of the x-ray beam while rotating the material to maintain the beam's focal point at a fixed point in the specimen undergoing analysis.

Adams, Bernhard W; Chollet, Matthieu C

2013-12-17T23:59:59.000Z

132

Continuous lengths of oxide superconductors  

DOE Patents [OSTI]

A layered oxide superconductor prepared by depositing a superconductor precursor powder on a continuous length of a first substrate ribbon. A continuous length of a second substrate ribbon is overlaid on the first substrate ribbon. Sufficient pressure is applied to form a bound layered superconductor precursor powder between the first substrate ribbon and the second substrate ribbon. The layered superconductor precursor is then heat treated to establish the oxide superconducting phase. The layered oxide superconductor has a smooth interface between the substrate and the oxide superconductor.

Kroeger, Donald M. (Knoxville, TN); List, III, Frederick A. (Andersonville, TN)

2000-01-01T23:59:59.000Z

133

Selected Experimental Highlights from Nucleus-Nucleus Collisions at RHIC  

E-Print Network [OSTI]

Nucleus-nucleus collisions at RHIC produce high temperature and high energy density matter which exhibits partonic degrees of freedom. We will discuss measurements of nuclear modification factors for light hadrons and non-photonic electrons from heavy quark decays, which reflect the flavor dependence of energy loss of high momentum partons traversing the dense QCD medium. The hadronization of bulk partonic matter exhibits collectivity in effective partonic degrees of freedom. Nuclear collisions at RHIC provide an intriguing environment, where many constituent quark ingredients are readily available for possible formation of exotic particles through quark coalescences or recombinations.

Huan Z. Huang

2006-08-29T23:59:59.000Z

134

Radiological consequences of ship collisions that might occur in U.S. Ports during the shipment of foreign research reactor spent nuclear fuel to the United States in break-bulk freighters  

SciTech Connect (OSTI)

Accident source terms, source term probabilities, consequences, and risks are developed for ship collisions that might occur in U.S. ports during the shipment of spent fuel from foreign research reactors to the United States in break-bulk freighters.

Sprung, J.L.; Bespalko, S.J.; Massey, C.D.; Yoshimura, R. [Sandia National Laboratory, Albuquerque, NM (United States); Johnson, J.D. [GRAM Inc., Albuquerque, NM (United States); Reardon, P.C. [PCRT Technologies, Albuquerque, NM (United States); Ebert, M.W.; Gallagher D.W. [Science Applications International Corp., Reston, VA (United States)

1996-08-01T23:59:59.000Z

135

Measurement of Inclusive Jet Charged-Particle Fragmentation Functions in Pb+Pb Collisions at ?s[subscript NN] = 2.76 TeV with the ATLAS Detector  

E-Print Network [OSTI]

Measurements of charged-particle fragmentation functions of jets produced in ultra-relativistic nuclear collisions can provide insight into the modification of parton showers in the hot, dense medium created in the collisions. ...

Taylor, Frank E.

136

Aircraft collision models  

E-Print Network [OSTI]

Introduction: The threat of midair collisions is one of the most serious problems facing the air traffic control system and has been studied by many researchers. The gas model is one of the models which describe the expected ...

Endoh, Shinsuke

1982-01-01T23:59:59.000Z

137

Jet Reconstruction in Heavy Ion Collisions  

E-Print Network [OSTI]

Measurements of strong suppression of inclusive hadron distributions and di-hadron correlations at high $p_{T}$, while providing evidence for partonic energy loss, also suffer from geometric biases due to the competition of energy loss and fragmentation. The measurements of fully reconstructed jets is expected to lack these biases as the energy flow is measured independently of the fragmentation details. In this article, we review the recent results from the heavy ion collisions collected by the STAR experiment at RHIC on direct jet reconstruction utilizing the modern sequential recombination and cone jet reconstruction algorithms together with their background subtraction techniques. In order to assess the jet reconstruction biases a comparison with the jet cross section measurement in $\\sqrt{s}=200$ GeV p+p collisions scaled by the number of binary nucleon-nucleon collisions to account for nuclear geometric effects is performed. Comparison of the inclusive jet cross section obtained in central Au+Au events with that in $p+p$ collisions, published previously by STAR, suggests that unbiased jet reconstruction in the complex heavy ion environment indeed may be possible.

Sevil Salur

2009-05-12T23:59:59.000Z

138

Azimuthal anisotropy in U+U collisions at STAR  

E-Print Network [OSTI]

The azimuthal anisotropy of particle production is commonly used in high-energy nuclear collisions to study the early evolution of the expanding system. The prolate shape of uranium nuclei makes it possible to study how the geometry of the colliding nuclei affects final state anisotropies. It also provides a unique opportunity to understand how entropy is produced in heavy ion collisions. In this paper, the two- and four- particle cumulant $v_2$ ($v_{2}\\{2\\}$ and $v_{2}\\{4\\}$) from U+U collisions at $\\sqrt{s_{NN}}$ = 193 GeV and Au+Au collisions at $\\sqrt{s_{NN}}$ = 200 GeV for inclusive charged hadrons will be presented. The STAR Zero Degree Calorimeters are used to select very central collisions. Differences were observed between the multiplicity dependence of $v_{2}\\{2\\}$ for most central Au+Au and U+U collisions. The multiplicity dependence of $v_{2}\\{2\\}$ in central collisions were compared to Monte Carlo Glauber model predictions and it was seen that this model cannot explain the present results.

Hui Wang; Paul Sorensen

2014-06-29T23:59:59.000Z

139

Azimuthal anisotropy in U+U collisions at STAR  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

The azimuthal anisotropy of particle production is commonly used in high-energy nuclear collisions to study the early evolution of the expanding system. The prolate shape of uranium nuclei makes it possible to study how the geometry of the colliding nuclei affects #12;final state anisotropies. It also provides a unique opportunity to understand how entropy is produced in heavy ion collisions. In this paper, the two- and four- particle cumulant v2 (v2{2} and v2{4}) from U+U collisions at ?sNN = 193 GeV and Au+Au collisions at ?sNN = 200 GeV for inclusive charged hadrons will be presented. The STAR Zero Degree Calorimeters are used to select very central collisions. Differences were observed between the multiplicity dependence of v2{2} for most central Au+Au and U+U collisions. The multiplicity dependence of v2{2} in central collisions were compared to Monte Carlo Glauber model predictions and it was seen that this model cannot explain the present results. (auth)

Wang, Hui; Sorensen, Paul

2014-12-01T23:59:59.000Z

140

Fragmentation in central collisions of heavy systems  

SciTech Connect (OSTI)

One of the goals of heavy ion reaction studies is to understand the fragmentation of hot nuclei. The LBL/GSI Plastic Ball detector system has been used to achieve a very high solid angle for detection of light and medium-heavy fragments emitted in 200 Mev/A Au + Au and Au + Fe reactions. The simultaneous measurement of almost all of the nucleons and nuclei resulting from each collision allows an estimation of the total charged particle multiplicity and hence the impact parameter. By choosing subsets of the data corresponding to a peripheral or central collision, the assumptions inherent in various models of nuclear fragmentation can be tested. 3 refs., 3 figs.

Claesson, G.; Doss, K.G.R.; Ferguson, R.; Gavron, A.; Gustafsson, H.A.; Gutbrod, H.H.; Harris, J.W.; Jacak, B.V.; Kampert, K.H.; Kolb, B.

1987-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Energy loss of charm quarks from $J/?$ production in cold nuclear matter  

E-Print Network [OSTI]

$J/\\psi$ suppression in p-A collisions is studied by considering the nuclear effects on parton distribution, energy loss of beam proton and the finial state energy loss of color octet $c\\overline{c}$. The leading-order computations for $J/\\psi$ production cross-section ratios $R_{W/Be}(x_{F})$ are presented and compared with the selected E866 experimental data with the $c\\overline{c}$ remaining colored on its entire path in the medium. It is shown that the combination of the different nuclear effects accounts quite well for the observed $J/\\psi$ suppression in the experimental data. It is found that the $J/\\psi$ suppression on $R_{W/Be}(x_{F})$ from the initial state nuclear effects is more important than that induced by the energy loss of color octet $c\\overline{c}$ in the large $x_F$ region. Whether the $c\\overline{c}$ pair energy loss is linear or quadratic with the path length is not determined. The obtained $c\\overline{c}$ pair energy loss per unit path length $\\alpha=2.78\\pm0.81$ GeV/fm, which indicates that the heavy quark in cold nuclear matter can lose more energy compared to the outgoing light quark.

Li-Hua Song; Wen-Dan Miao; Chun-Gui Duan

2013-12-15T23:59:59.000Z

142

A short course on Relativistic Heavy Ion Collisions  

E-Print Network [OSTI]

Some ideas/concepts in relativistic heavy ion collisions are discussed. To a large extent, the discussions are non-comprehensive and non-rigorous. It is intended for fresh graduate students of Homi Bhabha National Institute, Kolkata Centre, who are intending to pursue career in theoretical /experimental high energy nuclear physics. Comments and criticisms will be appreciated.

A. K. Chaudhuri

2012-07-23T23:59:59.000Z

143

A short course on Relativistic Heavy Ion Collisions  

E-Print Network [OSTI]

Some ideas/concepts in relativistic heavy ion collisions are discussed. To a large extent, the discussions are non-comprehensive and non-rigorous. It is intended for fresh graduate students of Homi Bhabha National Institute, Kolkata Centre, who are intending to pursue career in theoretical /experimental high energy nuclear physics. Comments and criticisms will be appreciated.

Chaudhuri, A K

2012-01-01T23:59:59.000Z

144

Microscope collision protection apparatus  

DOE Patents [OSTI]

A microscope collision protection apparatus for a remote control microscope which protects the optical and associated components from damage in the event of an uncontrolled collision with a specimen, regardless of the specimen size or shape. In a preferred embodiment, the apparatus includes a counterbalanced slide for mounting the microscope's optical components. This slide replaces the rigid mounts on conventional upright microscopes with a precision ball bearing slide. As the specimen contacts an optical component, the contacting force will move the slide and the optical components mounted thereon. This movement will protect the optical and associated components from damage as the movement causes a limit switch to be actuated, thereby stopping all motors responsible for the collision.

DeNure, Charles R. (Pocatello, ID)

2001-10-23T23:59:59.000Z

145

Jet absorption and corona effect at RHIC. Extracting collision geometry from experimental data  

E-Print Network [OSTI]

We demonstrate a possible existence of a finite formation time of strongly interacting plasma in nuclear collisions at RHIC from recent experimental data. To show this, we use a simple model based on Monte Carlo simulation of nucleus-nucleus collisions with realistic nuclear density distribution. The most striking feature of the experimental data - an absence of absorption of high transverse momentum pions in the reaction plane direction for mid-peripheral collisions - points to the presence of a surface zone with no absorption and strong suppression in the inner core. A natural interpretation of such a zone could be the plasma formation time T~2-3 fm/c. The existence of a formation time could dramatically change our understanding of many experimentally observed features. With this assumption we describe the angular anisotropy of high transverse momentum pions with respect to the reaction plane and the centrality dependence of nuclear modification factor in Au+Au and Cu+Cu collisions.

V. S. Pantuev

2007-05-14T23:59:59.000Z

146

The Dynamical Dipole Radiation in Dissipative Collisions with Exotic Beams  

E-Print Network [OSTI]

Heavy Ion Collisions (HIC) represent a unique tool to probe the in-medium nuclear interaction in regions away from saturation. In this work we present a selection of reaction observables in dissipative collisions particularly sensitive to the isovector part of the interaction, i.e. to the symmetry term of the nuclear Equation of State (EoS). At low energies the behavior of the symmetry energy around saturation influences dissipation and fragment production mechanisms. We will first discuss the recently observed Dynamical Dipole Radiation, due to a collective neutron-proton oscillation during the charge equilibration in fusion and deep-inelastic collisions. We will review in detail all the main properties, yield, spectrum, damping and angular distributions, revealing important isospin effects. Reactions induced by unstable 132Sn beams appear to be very promising tools to test the sub-saturation Isovector EoS. Predictions are also presented for deep-inelastic and fragmentation collisions induced by neutron rich projectiles. The importance of studying violent collisions with radioactive beams at low and Fermi energies is finally stressed.

M. Di Toro; M. Colonna; C. Rizzo; V. Baran

2007-11-22T23:59:59.000Z

147

Nuclear Physics of Neutron Stars  

E-Print Network [OSTI]

Understanding the equation of state (EOS) of cold nuclear matter, namely, the relation between the pressure and energy density, is a central goal of nuclear physics that cuts across a variety of disciplines. Indeed, the limits of nuclear existence, the collision of heavy ions, the structure of neutron stars, and the dynamics of core-collapse supernova, all depend critically on the equation of state of hadronic matter. In this contribution I will concentrate on the special role that nuclear physics plays in constraining the EOS of cold baryonic matter and its impact on the properties of neutron stars.

J. Piekarewicz

2009-01-28T23:59:59.000Z

148

Resonant electron-CF collision processes  

SciTech Connect (OSTI)

Electronic structure methods are combined with variationalfixed-nuclei electron scattering calculations and nuclear dynamicsstudies to characterize resonant vibrational excitation and electronattachment processes in collisions between low-energy electrons and CFradicals. Several low-lying negative ion states are found which give riseto strong vibrational excitation and which are expected to dominate thelow-energy electron scattering cross sections. We have also studiedseveral processes which could lead to production of negative ions (F- andC-), However, in contrast to other recent predictions, we do not find CFin itsground state to be a significant source of negative ion productionwhen interacting with thermal electrons.

Trevisan, Cynthia S.; Orel, Ann E.; Rescigno, Thomas N.

2005-03-18T23:59:59.000Z

149

Precision Measurement of the n-3He Incoherent Scattering Length Using Neutron Interferometry  

E-Print Network [OSTI]

We report the first measurement of the low-energy neutron-$^3$He incoherent scattering length using neutron interferometry: $b_i' = (-2.512\\pm 0.012{statistical}\\pm0.014{systematic})$ fm. This is in good agreement with a recent calculation using the AV18+3N potential. The neutron-$^3$He scattering lengths are important for testing and developing nuclear potential models that include three nucleon forces, effective field theories for few-body nuclear systems, and neutron scattering measurements of quantum excitations in liquid helium. This work demonstrates the first use of a polarized nuclear target in a neutron interferometer.

M. G. Huber; M. Arif; T. C. Black; W. C. Chen; T. R. Gentile; D. S. Hussey; D. Pushin; F. E. Wietfeldt; L. Yang

2009-05-12T23:59:59.000Z

150

Photon-photon collisions  

SciTech Connect (OSTI)

Highlights of the VIIIth International Workshop on Photon-Photon Collisions are reviewed. New experimental and theoretical results were reported in virtually every area of ..gamma gamma.. physics, particularly in exotic resonance production and tests of quantum chromodynamics where asymptotic freedom and factorization theorems provide predictions for both inclusive and exclusive ..gamma gamma.. reactions at high momentum transfer. 73 refs., 12 figs.

Brodsky, S.J.

1988-07-01T23:59:59.000Z

151

Elementary Collisions with HADES  

E-Print Network [OSTI]

The "High Acceptance DiElectron Spectrometer" (HADES) at GSI, Darmstadt, is investigating the production of e+e- pairs in A+A, p+A and N+N collisions. The latter program allows for the reconstruction of individual sources. This strategy will be roughly outlined in this contribution and preliminary pp/pn data is shown.

Fröhlich, I; Agakichiev, G; Agodi, C; Balanda, A; Bellia, G; Belver, D; Belyaev, A; Blanco, A; Böhmer, M; Boyard, J L; Braun-Munzinger, P; Cabanelas, P; Castro, E; Chernenko, S; Christ, T; Destefanis, M; Daz, J; Dohrmann, F; Dybczak, A; Eberl, T; Fabbietti, L; Fateev, O; Finocchiaro, P; Fonte, Paulo J R; Friese, J; Galatyuk, T; Garzn, J A; Gernhuser, R; Gilardi, C; Golubeva, M; Gonzalez-Diaz, D; Grosse, E; Guber, F; Heilmann, M; Hennino, T; Holzmann, R; Ierusalimov, A; Iori, I; Ivashkin, A; Jurkovic, M; Kmpfer, B; Kanaki, K; Karavicheva, T; Kirschner, D; König, I; König, W; Kolb, B W; Kotte, R; Kozuch, A; Krizek, F; Krcken, R; Khn, W; Kugler, A; Kurepin, A; Lamas-Valverde, J; Lang, S; Lange, J S; Lopes, L; Maier, L; Mangiarotti, A; Marn, J; Markert, J; Metag, V; Michalska, B; Mishra, D; Morinire, E; Mousa, J; Müntz, C; Naumann, Lutz; Novotny, R; Otwinowski, J; Pachmayer, Y C; Palka, M; Parpottas, Y; Pechenov, V; Pechenova, O; Prez Cavalcanti, T; Przygoda, W; Ramstein, B; Reshetin, A; Roy-Stephan, M; Rustamov, A; Sadovskii, A; Sailer, B; Salabura, P; Schmah, A; Simon, R; Spataro, S; Spruck, B; Strbele, H; Stroth, J; Sturm, C; Sudol, M; Tarantola, A; Teilab, K; Tlustý, P; Traxler, M; Trebacz, R; Tsertos, H; Veretenkin, I; Wagner, V; Wen, H; Wisniowski, M; Wojcik, T; Wstenfeld, J; Yurevich, S; Zanevsky, Y; Zumbruch, P

2007-01-01T23:59:59.000Z

152

Elementary Collisions with HADES  

E-Print Network [OSTI]

The "High Acceptance DiElectron Spectrometer" (HADES) at GSI, Darmstadt, is investigating the production of e+e- pairs in A+A, p+A and N+N collisions. The latter program allows for the reconstruction of individual sources. This strategy will be roughly outlined in this contribution and preliminary pp/pn data is shown.

I. Froehlich; for the HADES collaboration

2007-12-10T23:59:59.000Z

153

Thermally Fluctuating Second-Order Viscous Hydrodynamics and Heavy-Ion Collisions  

E-Print Network [OSTI]

The fluctuation-dissipation theorem requires the presence of thermal noise in viscous fluids. The time and length scales of heavy ion collisions are small enough so that the thermal noise can have a measurable effect on observables. Thermal noise is included in numerical simulations of high energy lead-lead collisions, increasing average values of the momentum eccentricity and contributing to its event by event fluctuations.

C. Young; J. I. Kapusta; C. Gale; S. Jeon; B. Schenke

2014-07-03T23:59:59.000Z

154

Effects of momentum-dependent nuclear potential on two-nucleon correlation functions and light cluster production in intermediate energy heavy-ion collisions RID A-2398-2009  

E-Print Network [OSTI]

Using an isospin- and momentum-dependent transport model, we study the effects due to the momentum dependence of isoscalar nuclear potential as well as that of symmetry potential on two-nucleon correlation functions and light cluster production...

Chen, LW; Ko, Che Ming; Li, Ba.

2004-01-01T23:59:59.000Z

155

Numerically Solvable Model for Resonant Collisions of Electronswith Diatomic Molecules  

SciTech Connect (OSTI)

We describe a simple model for electron-molecule collisions that has one nuclear and one electronic degree of freedom and that can be solved to arbitrarily high precision, without making the Born-Oppenheimer approximation, by employing a combination of the exterior complex scaling method and a finite-element implementation of the discrete variable representation. We compare exact cross sections for vibrational excitation and dissociative attachment with results obtained using the local complex potential approximation as commonly applied in the ''boomerang'' model, and suggest how this two-dimensional model can be used to test the underpinnings of contemporary nonlocal approximations to resonant collisions.

Houfek, Karel; Rescigno, T.N.; McCurdy, C.W.

2006-01-27T23:59:59.000Z

156

Initiative in Nuclear Theory at the Variable Energy Cyclotron Centre  

E-Print Network [OSTI]

We recall the path breaking contributions of the nuclear theory group of the Variable Energy Cyclotron Centre, Kolkata. From a beginning of just one person in 1970s, the group has steadily developed into a leading group in the country today, with seminal contributions to almost the entire range of nuclear physics, viz., low energy nuclear reactions, nuclear structure, deep inelastic collisions, fission, liquid to gas phase transitions, nuclear matter, equation of state, mass formulae, neutron stars, relativistic heavy ion collisions, medium modification of hadron properties, quark gluon plasma, and cosmology of early universe.

D. K. Srivastava; J. Alam; D. N. Basu; A. K. Chaudhuri; J. N. De; K. Krishan; S. Pal

2005-06-24T23:59:59.000Z

157

Pion and photon production in heavy ion collisions  

E-Print Network [OSTI]

Measurement of neutral pions and direct photons are closely connected experimentally, on the other hand they probe quite different aspects of relativistic heavy ion collisions. In this short review of the $\\pi^0$ results from the PHENIX experiment at RHIC our focus is on the $\\phi$-integrated nuclear modification factor, its energy and system size dependence, and the impact of these results on parton energy loss models. We also discuss the current status of high $p_T$ and thermal direct photon measurements both in $p$ + $p$ and Au+Au collisions. Recognizing the advantages of measuring not only the "signal", but also all the "references" needed for proper interpretation in the same experiments (with same or similar systematics) we argue that RHIC should regularly include $d$ + A and even $d$ + $d$ collisions into its system size and energy scan.

G. David

2009-03-02T23:59:59.000Z

158

Viscosity of High Energy Nuclear Fluids  

E-Print Network [OSTI]

Relativistic high energy heavy ion collision cross sections have been interpreted in terms of almost ideal liquid droplets of nuclear matter. The experimental low viscosity of these nuclear fluids have been of considerable recent quantum chromodynamic interest. The viscosity is here discussed in terms of the string fragmentation models wherein the temperature dependence of the nuclear fluid viscosity obeys the Vogel-Fulcher-Tammann law.

V. Parihar; A. Widom; D. Drosdoff; Y. N. Srivastava

2007-03-15T23:59:59.000Z

159

Planning under uncertainty for dynamic collision avoidance  

E-Print Network [OSTI]

We approach dynamic collision avoidance problem from the perspective of designing collision avoidance systems for unmanned aerial vehicles. Before unmanned aircraft can fly safely in civil airspace, robust airborne collision ...

Temizer, Selim, 1977-

2011-01-01T23:59:59.000Z

160

Measurement of inclusive jet spectra in pp, p-Pb, and Pb-Pb collisions with the ALICE detector  

E-Print Network [OSTI]

Highly energetic jets are sensitive probes for the kinematic properties and the topology of high energy hadron collisions. Jets are collimated sprays of charged and neutral particles, which are produced in fragmentation of hard scattered partons from an early stage of the collision. In ALICE, jets have been measured in pp, p-Pb, and Pb-Pb collisions at several collision energies. While analyses of Pb-Pb events unveil properties of the hot and dense medium formed in heavy-ion collisions, pp and p-Pb collisions can shed light on hadronization and cold nuclear matter effects in jet production. Additionally, pp and p-Pb serve as a baseline for disentangling hot and cold nuclear matter effects. A possible modification of the initial state is tested in p-Pb analyses. For the extraction of a jet signal, the exact evaluation of the background from the underlying event is an especially important ingredient. Due to the different nature of underlying events, each collision system requires a different analysis technique for removing the effect of the background on the jet sample. The focus of this publication is on the ALICE measurements of nuclear modification factors connecting p-Pb and Pb-Pb events to pp collisions. Furthermore, the radial jet structure is explored by comparing jet spectra reconstructed with different resolution parameters.

Rüdiger Haake; for the ALICE Collaboration

2014-10-16T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Jets in heavy ion collisions with ATLAS  

E-Print Network [OSTI]

The energy loss of high-p_T partons provides insight into the transport properties of the medium created in relativistic heavy ion collisions. Evidence for this energy loss was first experimentally established through observation of high-p_T hadron suppression at RHIC. More recently, measurements of fully reconstructed jets have been performed at the LHC. In this summary the latest experimental results from the ATLAS collaboration on jet suppression are presented. In particular the jet suppression in inclusive jet yields, path length dependence of the jet suppression, photon-jet and Z^0-jet correlations, heavy flavor suppression, and jet fragmentation are discussed. These results establish qualitative features of the jet quenching mechanism as experimental fact and provide constraints on models of jet energy loss.

Martin Spousta; for the ATLAS Collaboration

2012-11-14T23:59:59.000Z

162

Collision cascades and sputtering induced by larger cluster ions  

SciTech Connect (OSTI)

Recent experimental work on larger cluster impact on solid surfaces suggests large deviations from the standard case of additive sputter yields both in the nuclear and electronic stopping regime. The paper concentrates on elastic collision cascades. In addition to very pronounced spike effects, two phenomena are pointed out that are specific to cluster bombardment. Multiple hits of cluster atoms on one and the same target atom may result in recoil atoms that move faster than the maximum recoil speed for monomer bombardment at the same projectile speed. This effect is important when the atomic mass of a beam atom is less than that of a target atom, M1 << M2. In the opposite case, M1 >> M2, collisions between beam particles may accelerate some beam particles and slow down others. Some consequences are mentioned. Remarks on the nuclear stopping power of larger clusters and on electronic sputtering by cluster bombardment conclude the paper. 38 refs., 2 figs.

Sigmund, P.

1988-01-01T23:59:59.000Z

163

Heavy-flavour production and multiplicity dependence in pp and p--Pb collisions with ALICE  

E-Print Network [OSTI]

The production of heavy quarks in pp collisions provides a precision test of perturbative QCD calculations at the LHC energies. More complex collision systems like p--Pb collisions allow studies of cold nuclear matter effects, such as modifications of the parton distribution functions at small x and of the $\\kt$ broadening effect. We present the ALICE results of prompt D-meson production as a function of the charged-particle multiplicity, in pp and p--Pb collisions at $\\sqrt{s}=7$ TeV and $\\sqrt{s_{NN}}=5.02$ TeV respectively. The per-event yield of D mesons in different multiplicity and $\\pt$ intervals are compared for pp and p--Pb collisions to study the contribution of multi-parton interactions to open-charm production. Angular correlations of prompt D mesons and heavy-flavour decay electrons with charged hadrons in pp and p-Pb collisions are also shown in different kinematic ranges and compared to pQCD models. These measurements provide information on the charm fragmentation processes, on cold nuclear matter effects on charm production, and on the participation of charm in the collective motion arising in small collision systems like p-Pb.

Elena Bruna; for the ALICE Collaboration

2014-09-16T23:59:59.000Z

164

Sixteenth International Conference on the physics of electronic and atomic collisions  

SciTech Connect (OSTI)

This report contains abstracts of papers on the following topics: photons, electron-atom collisions; electron-molecule collisions; electron-ion collisions; collisions involving exotic species; ion- atom collisions, ion-molecule or atom-molecule collisions; atom-atom collisions; ion-ion collisions; collisions involving rydberg atoms; field assisted collisions; collisions involving clusters and collisions involving condensed matter.

Dalgarno, A.; Freund, R.S.; Lubell, M.S.; Lucatorto, T.B. (eds.)

1989-01-01T23:59:59.000Z

165

Isotope analysis in central heavy ion collisions at intermediate energies  

E-Print Network [OSTI]

Symmetry energy is a key quantity in the study of the equation of state of asymmetric nuclear matter. Heavy ion collisions at low and intermediate energies, performed at Laboratori Nazionali di Legnaro and Laboratori Nazionali del Sud, can be used to extract information on the symmetry energy coefficient Csym, which is currently poorly known but relevant both for astrophysics and for structure of exotic nuclei.

NUCL-EX Collaboration; :; E. Geraci; U. Abbondanno; L. Bardelli; S. Barlini; M. Bini; M. Bruno; F. Cannata; G. Casini; M. Chiari; M. D'Agostino; J. DeSanctis; A. Giussani; F. Gramegna; V. L. Kravchuk; A. L. Lanchais; P. Marini; A. Moroni; A. Nannini; A. Olmi; A. Ordine; G. Pasquali; S. Piantelli; G. Poggi; G. Vannini

2006-09-29T23:59:59.000Z

166

Nuclear reactor  

DOE Patents [OSTI]

A nuclear reactor comprising a cylindrical pressure vessel, an elongated annular core centrally disposed within and spaced from the pressure vessel, and a plurality of ducts disposed longitudinally of the pressure vessel about the periphery thereof, said core comprising an annular active portion, an annular reflector just inside the active portion, and an annular reflector just outside the active a portion, said annular active portion comprising rectangular slab, porous fuel elements radially disposed around the inner reflector and extending the length of the active portion, wedge-shaped, porous moderator elements disposed adjacent one face of each fuel element and extending the length of the fuel element, the fuel and moderator elements being oriented so that the fuel elements face each other and the moderator elements do likewise, adjacent moderator elements being spaced to provide air inlet channels, and adjacent fuel elements being spaced to provide air outlet channels which communicate with the interior of the peripheral ducts, and means for introducing air into the air inlet channels which passes through the porous moderator elements and porous fuel elements to the outlet channel.

Thomson, Wallace B. (Severna Park, MD)

2004-03-16T23:59:59.000Z

167

S-wave scattering lengths and effective ranges for collisions of ground state Be atoms  

E-Print Network [OSTI]

Jamieson,M.J. Cheung,A.S.C. Ouerdane,H. Jeung,G.H. Geum,N. Journal of Physics B, Volume 40 pp 3497-3504

Jamieson, M.J.

168

Past and present of nuclear matter  

SciTech Connect (OSTI)

The subject of nuclear matter is interesting for many fields of physics ranging from condensed matter to lattice QCD. Knowing its properties is important for our understanding of neutron stars, supernovae and cosmology. Experimentally, we have the most precise information on ground state nuclear matter from the mass formula and from the systematics of monopole vibrations. This gives us the ground state density, binding energy and the compression modulus k at ground state density. However, those methods can not be extended towards the regime we are most interested in, the regime of high density and high temperature. Additional information can be obtained from the observation of neutron stars and of supernova explosions. In both cases information is limited by the rare events that nature provides for us. High energy heavy ion collisions, on the other hand, allow us to perform controlled experiments in the laboratory. For a very short period in time we can create a system that lets us study nuclear matter properties. Density and temperature of the system depend on the mass of the colliding nuclei, on their energy and on the impact parameter. The system created in nuclear collisions has at best about 200 constituents not even close to infinite nuclear matter, and it lasts only for collision times of {approx} 10{sup {minus}22}sec, not an ideal condition for establishing any kind of equilibrium. Extended size and thermal and chemical equilibrium, however, axe a priori conditions of nuclear matter. As a consequence we need realistic models that describe the collision dynamics and non-equilibrium effects in order to relate experimental observables to properties of nuclear matter. The study of high energy nuclear collisions started at the Bevalac. I will try to summarize the results from the Bevalac studies, the highlights of the continuing program, and extension to higher energies without claiming to be complete.

Ritter, H.G.

1994-05-01T23:59:59.000Z

169

From Stopping to Viscosity in Heavy Ion Collisions  

SciTech Connect (OSTI)

Stopping in heavy ion collisions is investigated with the aim of learning about the shear viscosity of nuclear matter. Boltzmann equation simulations are compared to available data on stopping in the energy range of 20-117 MeV/nucleon. Stopping observables used include momentum anisotropy and linear momentum transfer. The data show that modeling the transport with free nucleon-nucleon cross-sections is inaccurate and reduced cross-sections are required. Reduction of the cross-sections produces an increase in the shear viscosity of nuclear matter, compared to calculations based on free cross-sections.

Barker, Brent W.; Danielewicz, Pawel [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States)

2010-04-26T23:59:59.000Z

170

Recent results on electroweak probes in lead-lead and proton-lead collisions from the ATLAS Detector at the LHC  

E-Print Network [OSTI]

Photons and weak bosons do not interact strongly with the dense and hot medium formed in nuclear collisions, and thus they should be sensitive to the nuclear modification of parton distribution functions (nPDFs). In particular, proton-lead collisions provide an excellent opportunity to test nPDFs in a less dense environment than lead-lead. The ATLAS detector, optimized for searching new physics in proton-proton collisions, is especially well equipped to measure photons, Z and W bosons in the high occupancy environment produced in heavy ion collisions. Using the full data samples of 2.76 TeV lead-lead and 5.02 TeV proton-lead collisions we will present recent results on the prompt photon, Z and W boson yields as a function of centrality, transverse momentum and rapidity, from the ATLAS experiment. The binary collision scaling of the yields will be discussed in detail.

Brooks, William; The ATLAS collaboration

2015-01-01T23:59:59.000Z

171

"Evidence for double-electron capture in the H9 -He collision"  

E-Print Network [OSTI]

V/amu have been prepared in a high-energy cluster facility consisting of a cryogenic cluster jet expansion selected high-energy projectile pulse (pulse length of 100 ms, repetition frequency of 1 Hz) consisting collision has been evidenced using the accelerator mass spectrometry method associated to a multi

Boyer, Edmond

172

Effect of Minimal lengths on Electron Magnetism  

E-Print Network [OSTI]

We study the magnetic properties of electron in a constant magnetic field and confined by a isotropic two dimensional harmonic oscillator on a space where the coordinates and momenta operators obey generalized commutation relations leading to the appearance of a minimal length. Using the momentum space representation we determine exactly the energy eigenvalues and eigenfunctions. We prove that the usual degeneracy of Landau levels is removed by the presence of the minimal length in the limits of weak and strong magnetic field.The thermodynamical properties of the system, at high temperature, are also investigated showing a new magnetic behavior in terms of the minimal length.

Khireddine Nouicer

2007-07-13T23:59:59.000Z

173

ZERO IMPACT PARAMETER WHITE DWARF COLLISIONS IN FLASH  

SciTech Connect (OSTI)

We systematically explore zero impact parameter collisions of white dwarfs (WDs) with the Eulerian adaptive grid code FLASH for 0.64 + 0.64 M {sub Sun} and 0.81 + 0.81 M {sub Sun} mass pairings. Our models span a range of effective linear spatial resolutions from 5.2 Multiplication-Sign 10{sup 7} to 1.2 Multiplication-Sign 10{sup 7} cm. However, even the highest resolution models do not quite achieve strict numerical convergence, due to the challenge of properly resolving small-scale burning and energy transport. The lack of strict numerical convergence from these idealized configurations suggests that quantitative predictions of the ejected elemental abundances that are generated by binary WD collision and merger simulations should be viewed with caution. Nevertheless, the convergence trends do allow some patterns to be discerned. We find that the 0.64 + 0.64 M {sub Sun} head-on collision model produces 0.32 M {sub Sun} of {sup 56}Ni and 0.38 M {sub Sun} of {sup 28}Si, while the 0.81 + 0.81 M {sub Sun} head-on collision model produces 0.39 M {sub Sun} of {sup 56}Ni and 0.55 M {sub Sun} of {sup 28}Si at the highest spatial resolutions. Both mass pairings produce {approx}0.2 M {sub Sun} of unburned {sup 12}C+{sup 16}O. We also find the 0.64 + 0.64 M {sub Sun} head-on collision begins carbon burning in the central region of the stalled shock between the two WDs, while the more energetic 0.81 + 0.81 M {sub Sun} head-on collision raises the initial post-shock temperature enough to burn the entire stalled shock region to nuclear statistical equilibrium.

Hawley, W. P.; Athanassiadou, T.; Timmes, F. X., E-mail: Wendy.Hawley@asu.edu [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287 (United States)

2012-11-01T23:59:59.000Z

174

A length operator for canonical quantum gravity  

E-Print Network [OSTI]

We construct an operator that measures the length of a curve in four-dimensional Lorentzian vacuum quantum gravity. We work in a representation in which a $SU(2)$ connection is diagonal and it is therefore surprising that the operator obtained after regularization is densely defined, does not suffer from factor ordering singularities and does not require any renormalization. We show that the length operator admits self-adjoint extensions and compute part of its spectrum which like its companions, the volume and area operators already constructed in the literature, is purely discrete and roughly is quantized in units of the Planck length. The length operator contains full and direct information about all the components of the metric tensor which faciliates the construction of a new type of weave states which approximate a given classical 3-geometry.

T. Thiemann

1996-06-29T23:59:59.000Z

175

Collision Geometry and Flow in Uranium+Uranium Collisions  

E-Print Network [OSTI]

Using event-by-event viscous fluid dynamics to evolve fluctuating initial density profiles from the Monte-Carlo Glauber model for U+U collisions, we report a "knee"-like structure in the elliptic flow as a function of collision centrality, located near 0.5% centrality as measured by the final charged multiplicity. This knee is due to the preferential selection of tip-on-tip collision geometries by a high-multiplicity trigger. Such a knee structure is not seen in the STAR data. This rules out the two-component MC-Glauber model for initial energy and entropy production. An enrichment of tip-tip configurations by triggering solely on high-multiplicity in the U+U collisions thus does not work. On the other hand, using the Zero Degree Calorimeters (ZDCs) coupled with event-shape engineering, we identify the selection purity of body-body and tip-tip events in the full-overlap U+U collisions. With additional constraints on the asymmetry of the ZDC signals one can further increases the probability of selecting tip-tip events in U+U collisions.

Andy Goldschmidt; Zhi Qiu; Chun Shen; Ulrich Heinz

2015-02-02T23:59:59.000Z

176

Canonical elements for collision orbits  

E-Print Network [OSTI]

I derive a set of canonical elements that are useful for collision orbits (perihelion distance approaching zero at fixed semimajor axis). The coordinates are the mean anomaly and the two spherical polar angles at aphelion.

Scott Tremaine

2000-12-12T23:59:59.000Z

177

Nuclear Waffles  

E-Print Network [OSTI]

The dense neutron-rich matter found in supernovae and neutron stars is expected to form complex nonuniform phases referred to as nuclear pasta. The pasta shapes depend on density, temperature and proton fraction and determine many transport properties in supernovae and neutron star crusts. We use two recently developed hybrid CPU/GPU codes to perform large scale molecular dynamics (MD) simulations with $51200$ and $409600$ nucleons of nuclear pasta. From the output of the MD simulations we characterize the topology and compute two observables, the radial distribution function $g(r)$ and the structure factor $S(q)$, for systems with proton fractions $Y_p=0.10, 0.20, 0.30$ and $0.40$ at about one third of nuclear saturation density and temperatures near $1.0$ MeV. We observe that the two lowest proton fraction systems simulated, $Y_p=0.10$ and $0.20$, equilibrate quickly and form liquid-like structures. Meanwhile, the two higher proton fraction systems, $Y_p=0.30$ and $0.40$, take a longer time to equilibrate and organize themselves in solid-like periodic structures. Furthermore, the $Y_p=0.40$ system is made up of slabs, lasagna phase, interconnected by defects while the $Y_p=0.30$ systems consist of a stack of perforated plates, the nuclear waffle phase. The periodic configurations observed in our MD simulations for proton fractions $Y_p\\ge0.30$ have important consequences for the structure factors $S(q)$ of protons and neutrons, which relate to many transport properties of supernovae and neutron star crust. A detailed study of the waffle phase and how its structure depends on temperature, size of the simulation and the screening length showed that finite-size effects appear to be under control and, also, that the plates in the waffle phase merge at temperatures slightly above $1.0$ MeV and the holes in the plates form an hexagonal lattice at temperatures slightly lower than $1.0$ MeV.

A. S. Schneider; D. K. Berry; C. M. Briggs; M. E. Caplan; C. J. Horowitz

2014-09-08T23:59:59.000Z

178

Centrality categorization for R_{p(d)+A} in high-energy collisions  

E-Print Network [OSTI]

High-energy proton- and deuteron-nucleus collisions provide an excellent tool for studying a wide array of physics effects, including modifications of parton distribution functions in nuclei, gluon saturation, and color neutralization and hadronization in a nuclear environment, among others. All of these effects are expected to have a significant dependence on the size of the nuclear target and the impact parameter of the collision, also known as the collision centrality. In this article, we detail a method for determining centrality classes in p(d)+A collisions via cuts on the multiplicity at backward rapidity (i.e., the nucleus-going direction) and for determining systematic uncertainties in this procedure. For d+Au collisions at sqrt(s_NN) = 200 GeV we find that the connection to geometry is confirmed by measuring the fraction of events in which a neutron from the deuteron does not interact with the nucleus. As an application, we consider the nuclear modification factors R_{p(d)+A}, for which there is a po...

Adare, A; Ajitanand, N N; Akiba, Y; Al-Bataineh, H; Alexander, J; Angerami, A; Aoki, K; Apadula, N; Aramaki, Y; Atomssa, E T; Averbeck, R; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Baksay, G; Baksay, L; Barish, K N; Bassalleck, B; Basye, A T; Bathe, S; Baublis, V; Baumann, C; Bazilevsky, A; Belikov, S; Belmont, R; Bennett, R; Bhom, J H; Blau, D S; Bok, J S; Boyle, K; Brooks, M L; Buesching, H; Bumazhnov, V; Bunce, G; Butsyk, S; Campbell, S; Caringi, A; Chen, C -H; Chi, C Y; Chiu, M; Choi, I J; Choi, J B; Choudhury, R K; Christiansen, P; Chujo, T; Chung, P; Chvala, O; Cianciolo, V; Citron, Z; Cole, B A; del Valle, Z Conesa; Connors, M; Csanád, M; Csörg?, T; Dahms, T; Dairaku, S; Danchev, I; Das, K; Datta, A; David, G; Dayananda, M K; Denisov, A; Deshpande, A; Desmond, E J; Dharmawardane, K V; Dietzsch, O; Dion, A; Donadelli, M; Drapier, O; Drees, A; Drees, K A; Durham, J M; Durum, A; Dutta, D; D'Orazio, L; Edwards, S; Efremenko, Y V; Ellinghaus, F; Engelmore, T; Enokizono, A; En'yo, H; Esumi, S; Fadem, B; Fields, D E; Finger, M; Jr., \\,; Fleuret, F; Fokin, S L; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fujiwara, K; Fukao, Y; Fusayasu, T; Garishvili, I; Glenn, A; Gong, H; Gonin, M; Goto, Y; de Cassagnac, R Granier; Grau, N; Greene, S V; Grim, G; Perdekamp, M Grosse; Gunji, T; Gustafsson, H -Ĺ; Haggerty, J S; Hahn, K I; Hamagaki, H; Hamblen, J; Han, R; Hanks, J; Haslum, E; Hayano, R; He, X; Heffner, M; Hemmick, T K; Hester, T; Hill, J C; Hohlmann, M; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hornback, D; Huang, S; Ichihara, T; Ichimiya, R; Ikeda, Y; Imai, K; Inaba, M; Isenhower, D; Ishihara, M; Issah, M; Ivanischev, D; Iwanaga, Y; Jacak, B V; Jia, J; Jiang, X; Jin, J; Johnson, B M; Jones, T; Joo, K S; Jouan, D; Jumper, D S; Kajihara, F; Kamin, J; Kang, J H; Kapustinsky, J; Karatsu, K; Kasai, M; Kawall, D; Kawashima, M; Kazantsev, A V; Kempel, T; Khanzadeev, A; Kijima, K M; Kikuchi, J; Kim, A; Kim, B I; Kim, D J; Kim, E -J; Kim, Y -J; Kinney, E; Kiss, Á; Kistenev, E; Kleinjan, D; Kochenda, L; Komkov, B; Konno, M; Koster, J; Král, A; Kravitz, A; Kunde, G J; Kurita, K; Kurosawa, M; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Lee, D M; Lee, J; Lee, K B; Lee, K S; Leitch, M J; Leite, M A L; Li, X; Lichtenwalner, P; Liebing, P; Levy, L A Linden; Liška, T; Liu, H; Liu, M X; Love, B; Lynch, D; Maguire, C F; Makdisi, Y I; Malik, M D; Manko, V I; Mannel, E; Mao, Y; Masui, H; Matathias, F; McCumber, M; McGaughey, P L; McGlinchey, D; Means, N; Meredith, B; Miake, Y; Mibe, T; Mignerey, A C; Miki, K; Milov, A; Mitchell, J T; Mohanty, A K; Moon, H J; Morino, Y; Morreale, A; Morrison, D P; Moukhanova, T V; Murakami, T; Murata, J; Nagamiya, S; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakamiya, Y; Nakamura, K R; Nakamura, T; Nakano, K; Nam, S; Newby, J; Nguyen, M; Nihashi, M; Nouicer, R; Nyanin, A S; Oakley, C; O'Brien, E; Oda, S X; Ogilvie, C A; Oka, M; Okada, K; Onuki, Y; Koop, J D Orjuela; Oskarsson, A; Ouchida, M; Ozawa, K; Pak, R; Pantuev, V; Papavassiliou, V; Park, I H; Park, S K; Park, W J; Pate, S F; Pei, H; Peng, J -C; Pereira, H; Perepelitsa, D; Peressounko, D Yu; Petti, R; Pinkenburg, C; Pisani, R P; Proissl, M; Purschke, M L; Qu, H; Rak, J; Ravinovich, I; Read, K F; Rembeczki, S; Reygers, K; Riabov, V; Riabov, Y; Richardson, E; Roach, D; Roche, G; Rolnick, S D; Rosati, M; Rosen, C A; Rosendahl, S S E; Ruži?ka, P; Sahlmueller, B; Saito, N; Sakaguchi, T; Sakashita, K; Samsonov, V; Sano, S; Sato, T; Sawada, S; Sedgwick, K; Seele, J; Seidl, R; Seto, R; Sharma, D; Shein, I; Shibata, T -A; Shigaki, K; Shimomura, M; Shoji, K; Shukla, P; Sickles, A; Silva, C L; Silvermyr, D; Silvestre, C; Sim, K S; Singh, B K; Singh, C P; Singh, V; Slune?ka, M; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Stankus, P W; Stenlund, E; Stoll, S P; Sugitate, T; Sukhanov, A; Sziklai, J; Takagui, E M; Taketani, A; Tanabe, R; Tanaka, Y; Taneja, S; Tanida, K; Tannenbaum, M J; Tarafdar, S; Taranenko, A; Themann, H; Thomas, D; Thomas, T L; Togawa, M; Toia, A; Tomášek, L; Torii, H; Towell, R S; Tserruya, I; Tsuchimoto, Y; Vale, C; Valle, H; van Hecke, H W; Vazquez-Zambrano, E; Veicht, A; Velkovska, J; Vértesi, R; Virius, M; Vrba, V; Vznuzdaev, E; Wang, X R; Watanabe, D; Watanabe, K; Watanabe, Y; Wei, F; Wei, R; Wessels, J; White, S N; Winter, D; Woody, C L; Wright, R M; Wysocki, M; Yamaguchi, Y L; Yamaura, K; Yang, R; Yanovich, A; Ying, J; Yokkaichi, S; You, Z; Young, G R; Younus, I; Yushmanov, I E; Zajc, W A; Zhou, S

2013-01-01T23:59:59.000Z

179

Hadron Production in Heavy Ion Collisions  

SciTech Connect (OSTI)

Heavy ion collisions are an ideal tool to explore the QCD phase diagram. The goal is to study the equation of state (EOS) and to search for possible in-medium modifications of hadrons. By varying the collision energy a variety of regimes with their specific physics interest can be studied. At energies of a few GeV per nucleon, the regime where experiments were performed first at the Berkeley Bevalac and later at the Schwer-Ionen-Synchrotron (SIS) at GSI in Darmstadt, we study the equation of state of dense nuclear matter and try to identify in-medium modifications of hadrons. Towards higher energies, the regime of the Alternating Gradient Synchrotron (AGS) at the Brookhaven National Laboratory (BNL), the Super-Proton Synchrotron (SPS) at CERN, and the Relativistic Heavy Ion Collider (RHIC) at BNL, we expect to produce a new state of matter, the Quark-Gluon Plasma (QGP). The physics goal is to identify the QGP and to study its properties. By varying the energy, different forms of matter are produced. At low energies we study dense nuclear matter, similar to the type of matter neutron stars are made of. As the energy is increased the main constituents of the matter will change. Baryon excitations will become more prevalent (resonance matter). Eventually we produce deconfined partonic matter that is thought to be in the core of neutron stars and that existed in the early universe. At low energies a great variety of collective effects is observed and a rather good understanding of the particle production has been achieved, especially that of the most abundantly produced pions and kaons. Many observations can be interpreted as time-ordered emission of various particle species. It is possible to determine, albeit model dependent, the equation of state of nuclear matter. We also have seen indications, that the kaon mass, especially the mass of the K{sup +}, might be modified by the medium created in heavy ion collisions. At AGS energies and above, emphasis shifts towards different aspects. Lattice QCD calculations predict the transition between a Quark-Gluon Plasma and a hadronic state at a critical temperature, T{sub c}, of about 150 to 190 MeV at vanishing baryon density. The energy density at the transition point is about 1:0 GeV/fm{sup 3}. It is generally assumed that chiral symmetry restoration happens simultaneously. In the high-energy regime, especially at RHIC, a rich field of phenomena [3] has revealed itself. Hot and dense matter with very strong collectivity has been created. There are indications that collectivity develops at the parton level, i.e. at a very early stage of the collision, when the constituents are partons rather than hadrons. Signs of pressure driven collective effects are our main tool for the study of the EOS. There are also strong indications that in the presence of a medium hadronization occurs through the process of quark coalescence and not through quark fragmentation, the process dominant for high-energy p+p reactions. We limit this report to the study of hadrons emitted in heavy ion reactions. The report is divided into two parts. The first part describes the phenomena observed from hadrons produced at low energies, whereas the second part concentrates on the search for signs of a partonic state at high energies.

Ritter, Hans Georg; Xu, Nu

2009-05-19T23:59:59.000Z

180

ATLAS Results from the first Pb-Pb Collisions  

E-Print Network [OSTI]

The ATLAS detector is capable of resolving the highest energy pp collisions at luminosities sufficient to yield 10's of simultaneous interactions within a bunch collision lasting ATLAS showed that the detector would have excellent performance also for the foreseeable particle multiplicities in the highest energy p-Pb and Pb-Pb collisions that the LHC will produce. These studies resulted in a letter of intent to the LHC committee by ATLAS to do physics with these beams also. In the past 2 years of data taking, ATLAS detector performance studies have confirmed these expectations at the actual multiplicities presented below. The ATLAS program removes an artificial specialization that arose about 30 years ago in high energy physics when the energy and intensity frontier moved to colliders. Before that time, for example, the same experiment that discovered the $\\Upsilon$ (CFS and E605 at Fermilab) also measured the nuclear modification factor in the production of high $p_T$ identified charged hadrons using nuclear targets from Beryllium through Tungsten.

Sebastian N. White

2011-11-11T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Forward hadron production in ultraperipheral proton-heavy-ion collisions at the LHC and RHIC  

E-Print Network [OSTI]

We discuss hadron production in the forward rapidity region in ultraperipheral proton-lead collisions at the LHC and proton-gold collisions at RHIC. Our discussion is based on the Monte Carlo simulations of the interactions of virtual photons emitted by a fast moving nucleus with a proton beam. We simulate the virtual photon flux with the STARLIGHT event generator and then particle production with the SOPHIA, DPMJET, and PYTHIA event generators. We show the rapidity distributions of charged and neutral particles, and the momentum distributions of neutral pions and neutrons at forward rapidities. According to the Monte Carlo simulations, we find large cross sections of ultraperipheral collisions for particle production especially in the very forward region, leading to substantial background contributions to investigations of collective nuclear effects and spin physics. Finally we can distinguish between proton-nucleus inelastic interactions and ultraperipheral collisions with additional requirements of either ...

Mitsuka, Gaku

2015-01-01T23:59:59.000Z

182

Towards Quantum Transport for Nuclear Reactions  

E-Print Network [OSTI]

Nonequilibrium Green's functions represent a promising tool for describing central nuclear reactions. Even at the single-particle level, though, the Green's functions contain more information that computers may handle in the foreseeable future. In this study, we investigate whether all the information contained in the Green's functions is necessarily relevant when describing the time evolution of nuclear reactions. For this, we carry out mean-field calculations of slab collisions in one dimension.

Danielewicz, Pawel; Barker, Brent

2009-01-01T23:59:59.000Z

183

Towards Quantum Transport for Nuclear Reactions  

E-Print Network [OSTI]

Nonequilibrium Green's functions represent a promising tool for describing central nuclear reactions. Even at the single-particle level, though, the Green's functions contain more information that computers may handle in the foreseeable future. In this study, we investigate whether all the information contained in the Green's functions is necessarily relevant when describing the time evolution of nuclear reactions. For this, we carry out mean-field calculations of slab collisions in one dimension.

Pawel Danielewicz; Arnau Rios; Brent Barker

2009-06-26T23:59:59.000Z

184

Experimental observables on nuclear liquid gas phase transition  

E-Print Network [OSTI]

Progress on nuclear liquid gas phase transition (LGPT) or critical behavior has been simply reviewed and some signals of LGPT in heavy ion collisions, especially in NIMROD data, are focused. These signals include the power-law charge distribution, the largest fluctuation of the fragment observables, the nuclear Zipf law, caloric curve and critical exponent analysis etc.

Y. G. Ma

2006-10-07T23:59:59.000Z

185

Collision Geometry and Flow in Uranium+Uranium Collisions  

E-Print Network [OSTI]

Using event-by-event viscous fluid dynamics to evolve fluctuating initial density profiles from the Monte-Carlo Glauber model for U+U collisions, we report a "knee"-like structure in the elliptic flow as a function of collision centrality, located near 0.5% centrality as measured by the final charged multiplicity. This knee is due to the preferential selection of tip-on-tip collision geometries by a high-multiplicity trigger. Such a knee structure is not seen in the STAR data. This rules out the two-component MC-Glauber model for initial energy and entropy production. An enrichment of tip-tip configurations by triggering solely on high-multiplicity in the U+U collisions thus does not work. On the other hand, using the Zero Degree Calorimeters (ZDCs) coupled with event-shape engineering, we identify the selection purity of body-body and tip-tip events in the full-overlap U+U collisions. With additional constraints on the asymmetry of the ZDC signals one can further increases the probability of selecting tip-ti...

Goldschmidt, Andy; Shen, Chun; Heinz, Ulrich

2015-01-01T23:59:59.000Z

186

Absorption Lengths in the Holographic Plasma  

E-Print Network [OSTI]

We consider the effect of a periodic perturbation with frequency $\\omega$ on the holographic N=4 plasma represented by the planar AdS black hole. The response of the system is given by exponentially decaying waves. The corresponding complex wave numbers can be found by solving wave equations in the AdS black hole background with infalling boundary conditions on the horizon in an analogous way as in the calculation of quasinormal modes. The complex momentum eigenvalues have an interpretation as poles of the retarded Green's functions, where the inverse of the imaginary part gives an absorption length $\\lambda$. At zero frequency we obtain the screening length for a static field. These are directly related to the glueball masses in the dimensionally reduced theory. We also point out that the longest screening length corresponds to an operator with non-vanishing R-charge and thus does not have an interpretation as a QCD3 glueball.

Irene Amado; Carlos Hoyos; Karl Landsteiner; Sergio Montero

2007-07-11T23:59:59.000Z

187

From sideward flow to nuclear compressibility  

SciTech Connect (OSTI)

We show that the differences between the Plastic Ball and DIOGENE experiments on sideward flow make it possible to asses independently, within the transport description of collisions, the effect of density dependence and momentum dependence of the nucleon optical potential. We estimate that the nuclear compressibility [ital K] lies between 180 and 235 MeV.

Pan, Q.; Danielewicz, P. (National Superconducting Cyclotron Laboratory and Department of Physics Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States))

1993-04-05T23:59:59.000Z

188

From Stopping to Viscosity in Nuclear Reactions  

SciTech Connect (OSTI)

Data on stopping in intermediate-energy central heavy-ion collisions are analyzed following transport theory based on the Boltzmann equation. In consequence, values of nuclear shear viscosity are inferred. The inferred values are significantly larger than obtained for free nucleon dispersion relations and free nucleon-nucleon cross sections.

Danielewicz, Pawel; Barker, Brent; Shi Lijun [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy Michigan State University, East Lansing, Michigan 48824 (United States)

2009-05-07T23:59:59.000Z

189

From Stopping to Viscosity in Nuclear Reactions  

E-Print Network [OSTI]

Data on stopping in intermediate-energy central heavy-ion collisions are analyzed following transport theory based on the Boltzmann equation. In consequence, values of nuclear shear viscosity are inferred. The inferred values are significantly larger than obtained for free nucleon dispersion relations and free nucleon-nucleon cross sections.

Danielewicz, P; Shi, L

2009-01-01T23:59:59.000Z

190

From Stopping to Viscosity in Nuclear Reactions  

E-Print Network [OSTI]

Data on stopping in intermediate-energy central heavy-ion collisions are analyzed following transport theory based on the Boltzmann equation. In consequence, values of nuclear shear viscosity are inferred. The inferred values are significantly larger than obtained for free nucleon dispersion relations and free nucleon-nucleon cross sections.

P. Danielewicz; B. Barker; L. Shi

2009-03-14T23:59:59.000Z

191

Sighting optics including an optical element having a first focal length and a second focal length  

DOE Patents [OSTI]

One embodiment of sighting optics according to the teachings provided herein may include a front sight and a rear sight positioned in spaced-apart relation. The rear sight includes an optical element having a first focal length and a second focal length. The first focal length is selected so that it is about equal to a distance separating the optical element and the front sight and the second focal length is selected so that it is about equal to a target distance. The optical element thus brings into simultaneous focus, for a user, images of the front sight and the target.

Crandall, David Lynn (Idaho Falls, ID)

2011-08-01T23:59:59.000Z

192

Anti-flow of K$^0_s$ Mesons in 6 AGeV Au + Au Collisions  

E-Print Network [OSTI]

We have measured the sideward flow of neutral strange ($K^0_s$) mesons in 6 AGeV Au + Au collisions. A prominent anti-flow signal is observed for an impact parameter range (b $\\lesssim 7$ fm) which spans central and mid-central events. Since the $K^0_s$ scattering cross section is relatively small in nuclear matter, this observation suggests that the in-medium kaon vector potential plays an important role in high density nuclear matter.

P. Chung; N. N. Ajitanand; J. M. Alexander; M. Anderson; D. Best; F. P. Brady; T. Case; W. Caskey; D. Cebra; J. L. Chance; B. Cole; K. Crowe; A. Das; J. E. Draper; M. L. Gilkes; S. Gushue; M. Heffner; A. S. Hirsch; E. L. Hjort; L. Huo; M. Justice; M. Kaplan; D. Keane; J. C. Kintner; J. Klay; D. Krofcheck; R. A. Lacey; J. Lauret; M. A. Lisa; H. Liu; Y. M. Liu; R. McGrath; Z. Milosevich; G. Odyniec; D. L. Olson; S. Y. Panitkin; C. Pinkenburg; N. T. Porile; G. Rai; H. G. Ritter; J. L. Romero; R. Scharenberg; L. Schroeder; B. Srivastava; N. T. BStone; T. J. M. Symons; T. Wienold; R. Witt J. Whitfield; L. Wood; W. N. Zhang

2001-01-06T23:59:59.000Z

193

Nuclear Resonance Fluorescence for Nuclear Materials Assay  

E-Print Network [OSTI]

Potential of Nuclear Resonance Fluorescence . . . . . . . .2.9.1 Nuclear ThomsonSections . . . . . . . . . . . . . . . Nuclear Resonance

Quiter, Brian Joseph

2010-01-01T23:59:59.000Z

194

Measurements of heavy-flavour production and azimuthal anisotropy in Pb--Pb collisions with the ALICE detector  

E-Print Network [OSTI]

Hadrons containing heavy quarks, i.e. charm or beauty, are unique probes of the properties of the hot and dense QCD medium produced in heavy-ion collisions. Due to their large masses, heavy quarks are produced at the initial stage of the collision, almost exclusively via hard partonic scattering processes. Therefore, they are expected to experience the full collision history propagating through the QCD medium losing energy via elastic and inelastic collisions with the medium constituents. The ALICE collaboration has measured the production of open heavy-flavour hadrons via their hadronic and semi-electronic decays at mid-rapidity and in the semi-muonic decay channel at \\mbox{forward rapidity} in pp, p--Pb and Pb--Pb collisions. In this talk the latest results on the open \\mbox{heavy-flavour nuclear modification factor, $R_\\mathrm{AA}$, and elliptic flow, $v_{2}$, are presented}.

Andrea Dubla; for the ALICE Collaboration

2014-10-17T23:59:59.000Z

195

Inheritance of Cotton Fiber Length and Strength  

E-Print Network [OSTI]

. Frequency distribution of upper half mean length (UHML) in the P1, P2, F1, BC1P1, BC1P2, and F2 generations for the parental combination of ELS33 (P1) x SID84 (P2) in 2010 and 2011. ..................................................... 63 Figure 4.... Frequency distribution of upper half mean length (UHML) in the P1, P2, F1, BC1P1, BC1P2, and F2 generations for the parental combination of ELS33 (P1) x HS624 (P2) in 2010 and 2011. ................................................................. 64...

Joy, Kolbyn Seth

2014-04-23T23:59:59.000Z

196

Apparatus for fabricating continuous lengths of superconductor  

DOE Patents [OSTI]

A process and apparatus for manufacturing a superconductor. The process is accomplished by depositing a superconductor precursor powder on a continuous length of a first substrate ribbon, overlaying a continuous length of a second substrate ribbon on said first substrate ribbon, and applying sufficient pressure to form a bound layered superconductor comprising a layer of said superconducting precursor powder between said first substrate ribbon and said second substrates ribbon. The layered superconductor is then heat treated to establish the superconducting phase of said superconductor precursor powder.

Kroeger, Donald M. (Knoxville, TN); List, III, Frederick A. (Andersonville, TN)

2002-01-01T23:59:59.000Z

197

Apparatus for fabricating continuous lengths of superconductor  

DOE Patents [OSTI]

A process and apparatus for manufacturing a superconductor. The process is accomplished by depositing a superconductor precursor powder on a continuous length of a first substrate ribbon, overlaying a continuous length of a second substrate ribbon on said first substrate ribbon, and applying sufficient pressure to form a bound layered superconductor comprising a layer of said superconducting precursor powder between said first substrate ribbon and said second substrates ribbon. The layered superconductor is then heat treated to establish the superconducting phase of said superconductor precursor powder.

Kroeger, Donald M. (Knoxville, TN); List, III, Frederick A. (Andersonville, TN)

2001-01-01T23:59:59.000Z

198

Crystal diffraction lens with variable focal length  

DOE Patents [OSTI]

A method and apparatus for altering the focal length of a focusing element of one of a plurality of pre-determined focal lengths by changing heat transfer within selected portions of the element by controlled quantities is disclosed. Control over heat transfer is accomplished by manipulating one or more of a number of variables, including: the amount of heat or cold applied to surfaces; type of fluids pumped through channels for heating and cooling; temperatures, directions of flow and rates of flow of fluids; and placement of channels. 19 figures.

Smither, R.K.

1991-04-02T23:59:59.000Z

199

Five Years of Tracking Heavy Ion Collisions at RHIC  

E-Print Network [OSTI]

Five years have passed since the first collisions of Au nuclei at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) on Long Island. With nucleon-nucleon center-of-mass energies of up to sqrt(s_NN)=200GeV RHIC provides the highest energy heavy ion collisions at any existing collider. To study the dynamics of nuclear matter at extreme temperatures and pressures hundreds of produced particles need to be tracked and identified, which provides a sizable challenge to the four experiments. This article tries to summarize these first years of RHIC operation from the detector point of view and give a glimpse at the future of the accelerator and its experiments.

A. Franz

2006-03-13T23:59:59.000Z

200

Temperature of projectile like fragments in heavy ion collisions  

E-Print Network [OSTI]

A model in which a projectile like fragment can be simply regarded as a remnant after removal of some part of the projectile leads to an excited fragment. This excitation energy can be calculated with a Hamiltonian that gives correct nuclear matter binding, compressibility and density distribution in finite nuclei. In heavy ion collisions the model produces a dependence of excitation energy on impact parameter which appears to be correct but the magnitude of the excitation energy falls short. It is argued that dynamic effects left out in the model will increase this magnitude. The model can be directly extended to include dynamics but at the expense of increased computation. For many calculations for observables, a temperature is an easier tool to use rather than an excitation energy. Hence temperature dependences on impact parameter in heavy ion collisions are displayed.

Gupta, S Das; Chaudhuri, G

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Temperature of projectile like fragments in heavy ion collisions  

E-Print Network [OSTI]

A model in which a projectile like fragment can be simply regarded as a remnant after removal of some part of the projectile leads to an excited fragment. This excitation energy can be calculated with a Hamiltonian that gives correct nuclear matter binding, compressibility and density distribution in finite nuclei. In heavy ion collisions the model produces a dependence of excitation energy on impact parameter which appears to be correct but the magnitude of the excitation energy falls short. It is argued that dynamic effects left out in the model will increase this magnitude. The model can be directly extended to include dynamics but at the expense of increased computation. For many calculations for observables, a temperature is an easier tool to use rather than an excitation energy. Hence temperature dependences on impact parameter in heavy ion collisions are displayed.

S. Das Gupta; S. Mallik; G. Chaudhuri

2013-09-27T23:59:59.000Z

202

An effective model for entropy deposition in high-energy pp, pA, and AA collisions  

E-Print Network [OSTI]

We introduce TRENTO, a new initial condition model for high-energy nuclear collisions based on eikonal entropy deposition via a "reduced thickness" function. The model simultaneously predicts the shapes of experimental proton-proton, proton-nucleus, and nucleus-nucleus multiplicity distributions, and generates nucleus-nucleus eccentricity harmonics consistent with experimental flow constraints. In addition, the model provides a possible resolution to the "knee" puzzle in ultra-central uranium-uranium collisions.

J. Scott Moreland; Jonah E. Bernhard; Steffen A. Bass

2014-12-15T23:59:59.000Z

203

Reaction product characteristics of the 65Cu+232Th violent collision at 35MeV/nucleon  

SciTech Connect (OSTI)

An exclusive experiment that imposed strong restrictive conditions has been performed at the Texas A&M K-500 superconducting cyclotron facility to study the formation and decay of hot nuclear system in the 35 AMeV 63Cu+232Th collision. Dynamical aspects of the collision between the projectile and target were simulated by the computer code CHIMERA which is based on the molecular dynamics concept.

Majka, Z.; Cibor, J.; Kozik, T. [Jagellonian Univ., Krakow (Poland)] [and others

1995-12-01T23:59:59.000Z

204

Two-pion Bose-Einstein correlations in pp collisions at sqrt(s)=900 GeV  

E-Print Network [OSTI]

We report on the measurement of two-pion correlation functions from pp collisions at sqrt(s)=900 GeV performed by the ALICE experiment at the Large Hadron Collider. Our analysis shows an increase of the HBT radius with increasing event multiplicity, in line with other measurements done in particle- and nuclear collisions. Conversely, the strong decrease of the radius with increasing transverse momentum, as observed at RHIC and at Tevatron, is not manifest in our data.

K. Aamodt; N. Abel; U. Abeysekara; A. Abrahantes Quintana; A. Abramyan; D. Adamova; M. M. Aggarwal; G. Aglieri Rinella; A. G. Agocs; S. Aguilar Salazar; Z. Ahammed; A. Ahmad; N. Ahmad; S. U. Ahn; R. Akimoto; A. Akindinov; D. Aleksandrov; B. Alessandro; R. Alfaro Molina; A. Alici; E. Almaraz Avina; J. Alme; T. Alt; V. Altini; S. Altinpinar; C. Andrei; A. Andronic; G. Anelli; V. Angelov; C. Anson; T. Anticic; F. Antinori; S. Antinori; K. Antipin; D. Antonczyk; P. Antonioli; A. Anzo; L. Aphecetche; H. Appelshauser; S. Arcelli; R. Arceo; A. Arend; N. Armesto; R. Arnaldi; T. Aronsson; I. C. Arsene; A. Asryan; A. Augustinus; R. Averbeck; T. C. Awes; J. Aysto; M. D. Azmi; S. Bablok; M. Bach; A. Badala; Y. W. Baek; S. Bagnasco; R. Bailhache; R. Bala; A. Baldisseri; A. Baldit; J. Ban; R. Barbera; G. G. Barnafoldi; L. S. Barnby; V. Barret; J. Bartke; F. Barile; M. Basile; V. Basmanov; N. Bastid; B. Bathen; G. Batigne; B. Batyunya; C. Baumann; I. G. Bearden; B. Becker; I. Belikov; R. Bellwied; E. Belmont-Moreno; A. Belogianni; L. Benhabib; S. Beole; I. Berceanu; A. Bercuci; E. Berdermann; Y. Berdnikov; L. Betev; A. Bhasin; A. K. Bhati; L. Bianchi; N. Bianchi; C. Bianchin; J. Bielcik; J. Bielcikova; A. Bilandzic; L. Bimbot; E. Biolcati; A. Blanc; F. Blanco; F. Blanco; D. Blau; C. Blume; M. Boccioli; N. Bock; A. Bogdanov; H. Boggild; M. Bogolyubsky; J. Bohm; L. Boldizsar; M. Bombara; C. Bombonati; M. Bondila; H. Borel; A. Borisov; C. Bortolin; S. Bose; L. Bosisio; F. Bossu; M. Botje; S. Bottger; G. Bourdaud; B. Boyer; M. Braun; P. Braun-Munzinger; L. Bravina; M. Bregant; T. Breitner; G. Bruckner; R. Brun; E. Bruna; G. E. Bruno; D. Budnikov; H. Buesching; P. Buncic; O. Busch; Z. Buthelezi; D. Caffarri; X. Cai; H. Caines; E. Calvo; E. Camacho; P. Camerini; M. Campbell; V. Canoa Roman; G. P. Capitani; G. Cara Romeo; F. Carena; W. Carena; F. Carminati; A. Casanova Diaz; M. Caselle; J. Castillo Castellanos; J. F. Castillo Hernandez; V. Catanescu; E. Cattaruzza; C. Cavicchioli; P. Cerello; V. Chambert; B. Chang; S. Chapeland; A. Charpy; J. L. Charvet; S. Chattopadhyay; S. Chattopadhyay; M. Cherney; C. Cheshkov; B. Cheynis; E. Chiavassa; V. Chibante Barroso; D. D. Chinellato; P. Chochula; K. Choi; M. Chojnacki; P. Christakoglou; C. H. Christensen; P. Christiansen; T. Chujo; F. Chuman; C. Cicalo; L. Cifarelli; F. Cindolo; J. Cleymans; O. Cobanoglu; J. -P. Coffin; S. Coli; A. Colla; G. Conesa Balbastre; Z. Conesa del Valle; E. S. Conner; P. Constantin; G. Contin; J. G. Contreras; Y. Corrales Morales; T. M. Cormier; P. Cortese; I. Cortes Maldonado; M. R. Cosentino; F. Costa; M. E. Cotallo; E. Crescio; P. Crochet; E. Cuautle; L. Cunqueiro; J. Cussonneau; A. Dainese; H. H. Dalsgaard; A. Danu; I. Das; A. Dash; S. Dash; G. O. V. de Barros; A. De Caro; G. de Cataldo; J. de Cuveland; A. De Falco; M. De Gaspari; J. de Groot; D. De Gruttola; N. De Marco; S. De Pasquale; R. De Remigis; R. de Rooij; G. de Vaux; H. Delagrange; Y. Delgado; G. Dellacasa; A. Deloff; V. Demanov; E. Denes; A. Deppman; G. D'Erasmo; D. Derkach; A. Devaux; D. Di Bari; C. Di Giglio; S. Di Liberto; A. Di Mauro; P. Di Nezza; M. Dialinas; L. Diaz; R. Diaz; T. Dietel; R. Divia; O. Djuvsland; V. Dobretsov; A. Dobrin; T. Dobrowolski; B. Donigus; I. Dominguez; D. M. M. Don; O. Dordic; A. K. Dubey; J. Dubuisson; L. Ducroux; P. Dupieux; A. K. Dutta Majumdar; M. R. Dutta Majumdar; D. Elia; D. Emschermann; A. Enokizono; B. Espagnon; M. Estienne; S. Esumi; D. Evans; S. Evrard; G. Eyyubova; C. W. Fabjan; D. Fabris; J. Faivre; D. Falchieri; A. Fantoni; M. Fasel; O. Fateev; R. Fearick; A. Fedunov; D. Fehlker; V. Fekete; D. Felea; B. Fenton-Olsen; G. Feofilov; A. Fernandez Tellez; E. G. Ferreiro; A. Ferretti; R. Ferretti; M. A. S. Figueredo; S. Filchagin; R. Fini; F. M. Fionda; E. M. Fiore; M. Floris; Z. Fodor; S. Foertsch; P. Foka; S. Fokin; F. Formenti; E. Fragiacomo; M. Fragkiadakis; U. Frankenfeld; A. Frolov; U. Fuchs; F. Furano; C. Furget; M. Fusco Girard; J. J. Gaardhoje; S. Gadrat; M. Gagliardi; A. Gago; M. Gallio; P. Ganoti; M. S. Ganti; C. Garabatos; C. Garcia Trapaga; J. Gebelein; R. Gemme; M. Germain; A. Gheata; M. Gheata; B. Ghidini; P. Ghosh; G. Giraudo; P. Giubellino; E. Gladysz-Dziadus; R. Glasow; P. Glassel; A. Glenn; R. Gomez Jimenez; H. Gonzalez Santos; L. H. Gonzalez-Trueba; P. Gonzalez-Zamora; S. Gorbunov; Y. Gorbunov; S. Gotovac; H. Gottschlag; V. Grabski; R. Grajcarek; A. Grelli; A. Grigoras; C. Grigoras; V. Grigoriev; A. Grigoryan; S. Grigoryan; B. Grinyov; N. Grion; P. Gros; J. F. Grosse-Oetringhaus; J. -Y. Grossiord; R. Grosso; F. Guber; R. Guernane; C. Guerra; B. Guerzoni; K. Gulbrandsen; H. Gulkanyan; T. Gunji; A. Gupta; R. Gupta; H. -A. Gustafsson; H. Gutbrod; O. Haaland; C. Hadjidakis; M. Haiduc; H. Hamagaki; G. Hamar; J. Hamblen; B. H. Han; J. W. Harris; M. Hartig; A. Harutyunyan; D. Hasch

2010-07-03T23:59:59.000Z

205

EA Systems Examples Induction and Recursion Length Measuring the Universe Analysis Number systems of different lengths,  

E-Print Network [OSTI]

EA Systems Examples Induction and Recursion Length Measuring the Universe Analysis Number systems of Mathematics University of Bristol April 21, 2008 Richard.Pettigrew@bris.ac.uk Natural number systems and infinitesimal analysis #12;EA Systems Examples Induction and Recursion Length Measuring the Universe Analysis

Forster, T.E.

206

Nuclear Physics A452 (19X6) 699-722 V'North-Holland Publishing Company  

E-Print Network [OSTI]

Nuclear Physics A452 (19X6) 699-722 V'North-Holland Publishing Company THE NUCLEAR LATTICE MODEL the essential features of the mass-yield curves, such as their U-shape and their power-law dependence for low. Introduction The production of complex fragments in nuclear collisions at intermediate and high energies

Bauer, Wolfgang

207

Nuclear Nonproliferation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Nuclear Nonproliferation As more countries embrace nuclear power as a cost-effective and clean alternative to fossil fuels, the need exists to ensure that the nuclear fuel cycle is...

208

Nuclear Engineering Nuclear Criticality Safety  

E-Print Network [OSTI]

Nuclear Engineering Nuclear Criticality Safety The Nuclear Engineering Division (NE) of Argonne National Laboratory is experienced in performing criticality safety and shielding evaluations for nuclear, and neutron spectra. The NE nuclear criticality safety (NCS) capabilities are based on a staff with decades

Kemner, Ken

209

Event characterization in (very) asymmetric collisions  

E-Print Network [OSTI]

Event-by-event reconstruction of the collision geometry using some incarnation of the Glauber-model is a widely accepted method in studying heavy ion collisions. While there is no known problem with the procedure when applied to the collision of two large ions, we will argue that in very asymmetric collisions, like $p(d)$+A with at least one hard scattering process occuring the event geometry deduced with the simple Glauber-model may be biased.

G. David

2014-09-24T23:59:59.000Z

210

Strangeness signals in heavy ion collisions  

SciTech Connect (OSTI)

The experimental data on strange meson and strange baryon production in relativistic heavy ion collisions are reviewed.

Remsberg, L.P.

1992-11-01T23:59:59.000Z

211

Strangeness signals in heavy ion collisions  

SciTech Connect (OSTI)

The experimental data on strange meson and strange baryon production in relativistic heavy ion collisions are reviewed.

Remsberg, L.P.

1992-01-01T23:59:59.000Z

212

Nuclear Physics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Underground Research Facility in South Dakota, which will search for neutrinoless double-beta decay. Strong Los Alamos programs in nuclear data and nuclear theory supports...

213

Nuclear Energy  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Nuclear Energy Idaho National Laboratory is the Department of Energy's lead nuclear energy research and development facility. Building upon its legacy responsibilities,...

214

Diffractive bremsstrahlung in hadronic collisions  

E-Print Network [OSTI]

Production of heavy photons (Drell-Yan), gauge bosons, Higgs bosons, heavy flavors, which is treated within the QCD parton model as a result of hard parton-parton collision, can be considered as a bremsstrahlung process in the target rest frame. In this review, we discuss the basic features of the diffractive channels of these processes in the framework of color dipole approach. The main observation is a dramatic breakdown of diffractive QCD factorisation due to the interplay between soft and hard interactions, which dominates these processes. This observation is crucial for phenomenological studies of diffractive reactions in high-energy hadronic collisions.

Pasechnik, Roman; Potashnikova, Irina

2015-01-01T23:59:59.000Z

215

Length dependence of the Raman spectra of carbon nanotubes  

E-Print Network [OSTI]

DNA-wrapping technology, combined with size-exclusion chromatography, have made possible the sorting of carbon nanotubes according to length. In particular, length sorted nanotube samples, with finite lengths approaching ...

Zare, Aurea Tucay

2009-01-01T23:59:59.000Z

216

Heavy Quark Production in ep Collisions  

E-Print Network [OSTI]

Heavy Quark Production in ep Collisions o Introduction o Charm Production o Beauty Production o in ep collisions 23 February 2007 2/17 Heavy Flavor Production Boson-Gluon Fusion, dominant process Hard of the proton: #12;G. Leibenguth, Heavy Quarks Production in ep collisions 23 February 2007 3/17 HERA, Electron

217

{phi} meson production in Au + Au and p + p collisions at {radical}s{sub NN}=200 GeV  

SciTech Connect (OSTI)

We report the STAR measurement of {psi} meson production in Au + Au and p + p collisions at {radical}s{sub NN} = 200 GeV. Using the event mixing technique, the {psi} spectra and yields are obtained at midrapidity for five centrality bins in Au+Au collisions and for non-singly-diffractive p+p collisions. It is found that the {psi} transverse momentum distributions from Au+Au collisions are better fitted with a single-exponential while the p+p spectrum is better described by a double-exponential distribution. The measured nuclear modification factors indicate that {psi} production in central Au+Au collisions is suppressed relative to peripheral collisions when scaled by the number of binary collisions (). The systematics of versus centrality and the constant {psi}/K{sup -} ratio versus beam species, centrality, and collision energy rule out kaon coalescence as the dominant mechanism for {psi} production.

Adams, J.; Adler, C.; Aggarwal, M.M.; Ahammed, Z.; Amonett, J.; Anderson, B.D.; Arkhipkin, D.; Averichev, G.S.; Badyal, S.K.; Balewski, J.; Barannikova, O.; Barnby, L.S.; Baudot, J.; Bekele, S.; Belaga, V.V.; Bellwied, R.; Berger, J.; Bezverkhny, B.I.; Bhardwaj, S.; Bhati, A.K.; Bichsel, H.; Billmeier, A.; Bland, L.C.; Blyth, C.O.; Bonner, B.E.; Botje, M.; Boucham, A.; Brandin, A.; Bravar, A.; Cadman, R.V.; Cai, X.Z.; Caines, H.; Calderon de la Barca Sanchez, M.; Carroll, J.; Castillo, J.; Cebra, D.; Chaloupka, P.; Chattopadhyay, S.; Chen, H.F.; Chen, Y.; Chernenko, S.P.; Cherney, M.; Chikanian, A.; Christie, W.; Coffin, J.P.; Cormier, T.M.; Cramer, J.G.; Crawford, H.J.; Das, D.; Das, S.; Derevschikov, A.A.; Didenko, L.; Dietel, T.; Dong, W.J.; Dong, X.; Draper, J.E.; Du, F.; Dubey, A.K.; Dunin, V.B.; Dunlop, J.C.; Dutta Majumdar, M.R.; Eckardt, V.; Efimov, L.G.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Fachini, P.; Faine, V.; Faivre, J.; Fatemi, R.; Filimonov, K.; Filip, P.; Finch, E.; Fisyak, Y.; Flierl, D.; Foley, K.J.; Fu, J.; Gagliardi, C.A.; Gagunashvili, N.; Gans, J.; Ganti, M.S.; Gaudichet, L.; Germain, M.; Geurts, F.; Ghazikhanian, V.; Ghosh, P.; Gonzalez, J.E.; Grachov, O.; Grebenyuk, O.; Gronstal, S.; Grosnick, D.; Guedon, M.; Guertin, S.M.; Gupta, A.; Gutierrez, T.D.; Hallman, T.J.; Hamed, A.; Hardtke, D.; Harris, J.W.; Heinz, M.; Henry, T.W.; Heppelmann, S.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffmann, G.W.; Horsley, M.; Huang, H.Z.; Huang, S.L.; Hughes, E.; Humanic, T.J.; Igo, G.; Ishihara, A.; Jacobs, P.; Jacobs, W.W.; Janik, M.; Johnson, I.; Jones, P.G.; Judd, E.G.; Kabana, S.; Kaplan, M.; Keane, D.; Khodyrev; Kiryluk, J.; Kisiel, A.; Klay, J.; Klein, S.R.; Klyachko, A.; Koetke, D.D.; Kollegger, T.; Kopytine, S.M.; Kotchenda, L.; Kovalenko, A.D.; Kramer, M.; Kravtsov, P.; Kravstov, V.I.; Krueger, K.; Kuhn, C.; Kulikov, A.I.; Kumar, A.; Kunde, G.J.; Kunz, C.L.; Kutuev, R.Kh.; et al.

2004-06-01T23:59:59.000Z

218

Nuclear Matter and Nuclear Dynamics  

E-Print Network [OSTI]

Highlights on the recent research activity, carried out by the Italian Community involved in the "Nuclear Matter and Nuclear Dynamics" field, will be presented.

M Colonna

2009-02-26T23:59:59.000Z

219

New hydrocracking catalysts increase throughput, run length  

SciTech Connect (OSTI)

An improved, second-stage hydrocracking catalyst has been developed by combining stabilized Y zeolites with amorphous silica alumina cracking components. A commercial application of this catalyst, along with a new, first-stage zeolitic hydrocracking catalyst, resulted in increased unit throughput and cycle length. The paper discusses the hydrocracking process, first-stage catalysts, second-stage catalysts, hydrogenation process, commercial results, and product properties.

Huizinga, T. [Shell Internationale Petroleum Mij., The Hague (Netherlands); Theunissen, J.M.H. [Rayong Refinery Co. Ltd., Rayong (Thailand); Minderhoud, H.; Veen, R. van [Koninklijke/Shell-Lab., Amsterdam (Netherlands)

1995-06-26T23:59:59.000Z

220

Critical length limiting super-low friction  

E-Print Network [OSTI]

Since the demonstration of super-low friction (superlubricity) in graphite at nanoscale, one of the main challenges in the field of nano- and micro-mechanics was to scale this phenomenon up. A key question to be addressed is to what extent superlubricity could persist, and what mechanisms could lead to its failure. Here, using an edge-driven Frenkel-Kontorova model, we establish a connection between the critical length above which superlubricity disappears and both intrinsic material properties and experimental parameters. A striking boost in dissipated energy with chain length emerges abruptly due to a high-friction stick-slip mechanism caused by deformation of the slider leading to a local commensuration with the substrate lattice. We derived a parameter-free analytical model for the critical length that is in excellent agreement with our numerical simulations. Our results provide a new perspective on friction and nano-manipulation and can serve as a theoretical basis for designing nano-devices with super-low friction, such as carbon nanotubes.

Ming Ma; Andrea Benassi; Andrea Vanossi; Michael Urbakh

2015-01-02T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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221

Heavy Quarkonia Production in p+p Collisions from the PHENIX Experiment  

E-Print Network [OSTI]

Quarkonia provide a sensitive probe of the properties of the hot dense medium created in high energy heavy ion collisions. Hard scattering processes result in the production of heavy quark pairs that interact with the collision medium during hadronization. These in-medium interactions convey information about the fundamental properties of the medium itself and can be used to examine the modification of the QCD confining potential in the collision environment. Baseline measurements from p+p and d+Au collision systems are used to distinguish cold nuclear matter effects while measurements from heavy ion collision systems are used to quantify in-medium effects. The PHENIX experiment has the capability of detecting heavy quarkonia at $1.2<|\\eta|<2.2$ via the $\\mu^+\\mu^-$ decay channel and at $|\\eta|<0.35$ via the $e^+e^-$ decay channel. Recent runs have resulted in the collection of high statistics p+p data sets that provide an essential baseline reference for heavy ion measurements and allow for further critical evaluation of heavy quarkonia production mechanisms. The latest PHENIX results for the production of the $J/\\psi$ in p+p collisions are presented and future prospects for $\\psi'$, $\\chi_{c}$ and $\\Upsilon$ measurements are discussed.

Abigail Bickley; for the PHENIX Collaboration

2007-01-22T23:59:59.000Z

222

Pairing Effects in Nuclear Fusion Reaction  

E-Print Network [OSTI]

We simulate a heavy-ion collision using the canonical-basis time-dependent Hartree-Fock-Bogoliubov theory (Cb-TDHFB) treating pairing correlation in the three-dimensional coordinate space. We apply the Cb-TDHFB to 22O+22O collision with a contact-type pairing energy functional, and compare results of Cb-TDHFB and TDHF to investigate the effects of pairing correlations in nuclear fusion. Our results seem to indicate that pairing effects do not increase the fusion cross section in this system.

Shuichiro Ebata; Takashi Nakatsukasa

2013-09-29T23:59:59.000Z

223

Scaling patterns for the suppression of charged hadron yields in Pb+Pb collisions at Root_s = 2.76 TeV: Constraints on transport coefficients  

E-Print Network [OSTI]

Suppression measurements for charged hadrons are used to investigate the path length (L) and transverse momentum (p_T) dependent jet quenching patterns of the hot and dense QCD medium produced in Pb+Pb collisions at Root_s =2.76 TeV at the LHC. The observed scaling patterns, which are similar to those observed for Au+Au collisions at Root_s = 0.20 TeV at RHIC, show the trends predicted for jet-medium interactions dominated by radiative energy loss. They also allow a simple estimate of the transport coefficient $\\hat{q}$, which suggests that the medium produced in LHC collisions is somewhat less opaque than that produced at RHIC, if the same parton-medium coupling strength is assumed. The higher temperature produced in LHC collisions could reduce the parton-medium coupling strength to give identical values for $\\hat{q}$ in LHC and RHIC collisions.

Roy A. Lacey; N. N. Ajitanand; J. M. Alexander; J. Jia; A. Taranenko

2012-02-24T23:59:59.000Z

224

Pion Interferometry in Au+Au and Cu+Cu Collisions at sqrt sNN = 62.4 and 200 GeV  

SciTech Connect (OSTI)

We present a systematic analysis of two-pion interferometry in Au+Au collisions at {radical}sNN = 62.4 GeV and Cu+Cu collisions at {radical}sNN = 62.4 and 200 GeV using the STAR detector at RHIC. The multiplicity and transverse momentum dependences of the extracted correlation lengths (radii) are studied. The scaling with charged particle multiplicity of the apparent system volume at final interaction is studied for the RHIC energy domain. The multiplicity scaling of the measured correlation radii is found to be independent of colliding system and collision energy.

STAR Collaboration; Abelev, B.I.

2009-08-24T23:59:59.000Z

225

IN SEARCH OF HIGH DENSITY COLLECTIVE PHENOMENA IN NUCLEAR COLLISION  

E-Print Network [OSTI]

42, 1448 (1979). P. J. Siemens, J. 0. Rasmussen, Phys. Rev.Discussions with P. Siemens, J. Randrup, and W. D. Myersl . , and interpreted by P. Siemens as evidence for a blast

Gyulassy, M.

2010-01-01T23:59:59.000Z

226

PION, LIGHT FRAGMENT AND ENTROPY PRODUCTION IN NUCLEAR COLLISIONS  

E-Print Network [OSTI]

Rev. C23 (1981) 1282. P. Siemens, J. Kapusta, Phys. Rev.I. Mishustin, I. Myhrer, P. Siemens, Phys. Lett. 958 (1980)private communications. P. Siemens, J. Rasmussen, Phys. Rev.

Stocker, Horst

2013-01-01T23:59:59.000Z

227

Property:Length (m) | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy ResourcesLoadingPenobscot County,ContAddr2 Jump to: navigation,PVYearsDisplay/GraphicsLength (m) Jump to:

228

TREKisM At Length Issue 2  

E-Print Network [OSTI]

. "Triskelian Fledgeling" — by Vel Jaeger "Kelvan Exile" — by Vel Jaeger 111. Romulan Astronomy — by Robert S. Sayes 113c Trek-M's Speak their Minds on ST:TMP 121. A Glance Backwards - reactions to TaL I (first issue of TREKisM at Length) 122. Trivia Quizes #3...\\un Speck run. "fynjrur^run. -Storu Ipu1- 'The^dds" UYena T^fc* Ink.nc l'*- bjj rafrick La\\fena ^aq Kidd LuckICKU ©/980' -14- 0N CONVENTIONAL OCCASIONS The following Is a conglomeration of reports, Interviews, and reminiscences from TREKisM members...

Multiple Contributors

1981-01-01T23:59:59.000Z

229

TREKiSM At Length Issue 5  

E-Print Network [OSTI]

Trek IV! SHALOM PAX PEACE to us all in 1986 Table of Contents TITLE AUTHOR ARTIST PAGE I. DATA ENTRIES FROST ON THE TYPEWRITER V.L. Thorn LaVena Kay Kldd 2 "Trek Omen" V.L. Thorn 6 (originally appeared In TREKisM #26) JAMES T. KIRK vs THE COMPUTER... appeared in TREKisM at Length III) TALES FROM THE VULCAN HEARTH Karen C. Hunter 53 HOW THE VULCANS LOST THEIR WINGS 54 THE SKY GOD'S DAUGHTER 56 THE GIFT OF THE GODS LaVena Kay Kldd 57 "Sul Generis" V.L. Thorn 58 "Cat-Kin" Emily Ross 60 (originally appeared...

Multiple Contributors

1988-01-01T23:59:59.000Z

230

TrekISM At Length Issue 3  

E-Print Network [OSTI]

Length III is published by the Star Trek Special Interest Group LSIGJ of Mensa. Copyright (c) 1983..., 1701 W. Third St, Brooklyn NY 11223. \\S In January Paramount STAR TREK new produc Star Trek' no time wa two-and-a- of TREKisM interested said in an Thank you, never ceas the contin eternally ixgmqp^ion of 19 P i c t u r II. A er, Ha...

Multiple Contributors

1983-01-01T23:59:59.000Z

231

Elliptic flow in heavy ion collisions near the balance energy  

E-Print Network [OSTI]

The proton elliptic flow in collisions of Ca on Ca at energies from 30 to 100 MeV/nucleon is studied in an isospin-dependent transport model. With increasing incident energy, the elliptic flow shows a transition from positive to negative flow. Its magnitude depends on both the nuclear equation of state (EOS) and the nucleon-nucleon scattering cross section. Different elliptic flows are obtained for a stiff EOS with free nucleon-nucleon cross sections and a soft EOS with reduced nucleon-nucleon cross sections, although both lead to vanishing in-plane transverse flow at the same balance energy. The study of both in-plane and elliptic flows at intermediate energies thus provides a means to extract simultaneously the information on the nuclear equation of state and the nucleon-nucleon scattering cross section in medium.

Yu-Ming Zheng; C. M. Ko; Bao-An Li; Bin Zhang

1999-06-24T23:59:59.000Z

232

Interception of comets and asteroids on collision course with earth  

SciTech Connect (OSTI)

I derive expressions for the weight and range of applicability of interceptors capable of deflecting a comet or asteroid on collision course with Earth. The expressions use a fairly general relationship between the energy deposited and the mass of material blown off the astral assailant. To assess the probability that the astral assailant will fracture, I also calculate the fraction of the astral assailant`s mass that will be blown off. The interaction is calculated for both kinetic-energy deflection and nuclear-explosive deflection. In the nuclear-explosive case, I calculate the interceptor mass and cratering effect for detonations above the surface and below the surface as well as directly on the surface of the astral assailant. Because the wide range of densities and material properties that the astral assailant may possess, the principal value of this work is to show the relationships among the salient parameters of the problem.

Solem, J.C.

1992-03-01T23:59:59.000Z

233

Interception of comets and asteroids on collision course with earth  

SciTech Connect (OSTI)

I derive expressions for the weight and range of applicability of interceptors capable of deflecting a comet or asteroid on collision course with Earth. The expressions use a fairly general relationship between the energy deposited and the mass of material blown off the astral assailant. To assess the probability that the astral assailant will fracture, I also calculate the fraction of the astral assailant's mass that will be blown off. The interaction is calculated for both kinetic-energy deflection and nuclear-explosive deflection. In the nuclear-explosive case, I calculate the interceptor mass and cratering effect for detonations above the surface and below the surface as well as directly on the surface of the astral assailant. Because the wide range of densities and material properties that the astral assailant may possess, the principal value of this work is to show the relationships among the salient parameters of the problem.

Solem, J.C.

1992-01-01T23:59:59.000Z

234

Medium induced jet absorption at relativistic heavy ion collisions  

E-Print Network [OSTI]

The dense medium created in Au + Au collisions at the Relativistic Heavy-Ion Collider (RHIC) significantly suppresses particle production from hard scattering processes and their characteristic back-to-back angular correlation. We present a simple model of jet absorption in dense matter which incorporates a realistic nuclear geometry. Our calculations are performed at the jet level and assume independent jet fragmentation in the vacuum. This model describes quantitatively the centrality dependence of the observed suppression of the high $p_T$ hadron yield and of the back-to-back angular correlations. The azimuthal anisotropy of high $p_T$ particle production can not be accounted for using a realistic nuclear geometry.

Axel Drees; Haidong Feng; Jiangyong Jia

2005-05-31T23:59:59.000Z

235

Nuclear reactor safety device  

DOE Patents [OSTI]

A safety device is described for use in a nuclear reactor for axially repositioning a control rod with respect to the reactor core in the event of a thermal excursion. It comprises a laminated strip helically configured to form a tube, said tube being in operative relation to said control rod. The laminated strip is formed of at least two materials having different thermal coefficients of expansion, and is helically configured such that the material forming the outer lamina of the tube has a greater thermal coefficient of expansion than the material forming the inner lamina of said tube. In the event of a thermal excursion the laminated strip will tend to curl inwardly so that said tube will increase in length, whereby as said tube increases in length it exerts a force on said control rod to axially reposition said control rod with respect to said core.

Hutter, E.

1983-08-15T23:59:59.000Z

236

Central collisions of heavy ions  

SciTech Connect (OSTI)

This report describes the activities of the Heavy Ion Physics Group at the University of California, Riverside from October 1, 1991 to September 30, 1992. During this period, the program focused on particle production at AGS energies, and correlation studies at the Bevalac in nucleus-nucleus central collisions. As part of the PHENIX collaboration, contributions were made to the Preliminary Conceptual Design Report (pCDR), and work on a RHIC silicon microstrip detector R D project was performed.

Fung, Sun-yiu.

1992-10-01T23:59:59.000Z

237

J/$?$ production in In-In and p-A collisions  

E-Print Network [OSTI]

The NA60 experiment studies dimuon production in In-In and p-A collisions at the CERN SPS. We report recent results on \\jpsi production, measured through its muon pair decay. As a function of centrality, we show that in In-In the \\jpsi yield is suppressed beyond expectations from nuclear absorption. We present also for the first time results on \\jpsi production in p-A collisions at 158 GeV, the same energy of the nucleus-nucleus data. For both p-A and In-In we show preliminary results on \\psip suppression. Finally, we have studied the kinematical distributions of the \\jpsi produced in In-In collisions. We present results on transverse momentum and rapidity, as well as on the angular distribution of the \\jpsi decay products.

E. Scomparin

2007-03-20T23:59:59.000Z

238

Determination of the impact vector in intermediate energy heavy ion collisions  

SciTech Connect (OSTI)

We examine a variety of methods for determining both the impact parameter and the direction of the impact vector in symmetric nuclear collisions at intermediate energies. Two quantities, the particle multiplicity and the midrapidity charge, retain their dependence on the impact parameter after filtering through the acceptance of a typical 4{pi} detector. By gating on these quantities we can select four ranges of impact parameters. There is some overlap of these ranges. It is noted that this is dependent on the model used to simulate the collisions. The midrapidity charge has the advantage that it integrates over the final fragments and should be less sensitive to how the collision zone disassembles. The angle of the impact vector is well reproduced with the method developed by Danielewicz and Odyniec. The difference between known and determined reaction plane has a half-width at half-maximum of less than 70{degree}. Some comparisons are made to experimental data.

Ogilvie, C.A.; Cebra, D.A.; Clayton, J.; Howden, S.; Karn, J.; Vander Molen, A.; Westfall, G.D.; Wilson, W.K.; Winfield, J.S. (National Superconducting Cyclotron Laboratory and Department of Physics Astronomy, Michigan State University, East Lansing, Michigan 48824 (US))

1989-08-01T23:59:59.000Z

239

Centrality dependence of high $p_T$ suppression in Au+Au collisions suggest quark matter formation  

E-Print Network [OSTI]

In a pQCD-based model, we have analyzed the STAR data on the high $p_T$ suppression of charged hadrons, in Au+Au collisions at $\\sqrt{s}$=200 GeV. In the jet quenching or the energy loss picture, $p_T$ spectra of charged hadrons as well as the $p_T$ dependence of nuclear modification factor, in all the centrality ranges, are well explained, with nearly a constant relative energy loss, $\\Delta E/E=0.56\\pm 0.03$. Centrality independence of relative energy loss indicate that the matter produced in central and in peripheral collisions are different, otherwise relative energy loss would have shown strong centrality dependence. Qualitatively, centrality independence of relative energy loss can be understood, if in central Au+Au collisions deconfined matter is produced and the matter remain confined in peripheral collisions.

A. K. Chaudhuri

2004-05-12T23:59:59.000Z

240

Nuclear reactor reflector  

DOE Patents [OSTI]

A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled.

Hopkins, Ronald J. (Pensacola, FL); Land, John T. (Pensacola, FL); Misvel, Michael C. (Pensacola, FL)

1994-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Nuclear reactor reflector  

DOE Patents [OSTI]

A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled. 12 figs.

Hopkins, R.J.; Land, J.T.; Misvel, M.C.

1994-06-07T23:59:59.000Z

242

Moving Away from Collision Avoidance: Towards Collision Detection in Wireless Networks  

E-Print Network [OSTI]

Nelakuditi University of South Carolina ABSTRACT Wireless networks are founded on the principles of collision to abort transmission. The collision notification consists of a unique signature, sent on the same transmissions. We call this Carrier Sense Multiple Access with Collision Notification (CSMA/CN). Early results

Nelakuditi, Srihari

243

Centrality dependence of the charged-particle multiplicity density at mid-rapidity in Pb-Pb collisions at sqrt(sNN) = 2.76 TeV  

E-Print Network [OSTI]

The centrality dependence of the charged-particle multiplicity density at mid-rapidity in Pb-Pb collisions at sqrt(sNN) = 2.76 TeV is presented. The charged-particle density normalized per participating nucleon pair increases by about a factor 2 from peripheral (70-80%) to central (0-5%) collisions. The centrality dependence is found to be similar to that observed at lower collision energies. The data are compared with models based on different mechanisms for particle production in nuclear collisions.

ALICE Collaboration; K. Aamodt; A. Abrahantes Quintana; D. Adamová; A. M. Adare; M. M. Aggarwal; G. Aglieri Rinella; A. G. Agocs; S. Aguilar Salazar; Z. Ahammed; N. Ahmad; A. Ahmad Masoodi; S. U. Ahn; A. Akindinov; D. Aleksandrov; B. Alessandro; R. Alfaro Molina; A. Alici; A. Alkin; E. Almaráz Avińa; T. Alt; V. Altini; S. Altinpinar; I. Altsybeev; C. Andrei; A. Andronic; V. Anguelov; C. Anson; T. Anti\\vci?; F. Antinori; P. Antonioli; L. Aphecetche; H. Appelshäuser; N. Arbor; S. Arcelli; A. Arend; N. Armesto; R. Arnaldi; T. Aronsson; I. C. Arsene; A. Asryan; A. Augustinus; R. Averbeck; T. C. Awes; J. Äystö; M. D. Azmi; M. Bach; A. Badalŕ; Y. W. Baek; S. Bagnasco; R. Bailhache; R. Bala; R. Baldini Ferroli; A. Baldisseri; A. Baldit; J. Bán; R. Barbera; F. Barile; G. G. Barnaföldi; L. S. Barnby; V. Barret; J. Bartke; M. Basile; N. Bastid; B. Bathen; G. Batigne; B. Batyunya; C. Baumann; I. G. Bearden; H. Beck; I. Belikov; F. Bellini; R. Bellwied; E. Belmont-Moreno; S. Beole; I. Berceanu; A. Bercuci; E. Berdermann; Y. Berdnikov; L. Betev; A. Bhasin; A. K. Bhati; L. Bianchi; N. Bianchi; C. Bianchin; J. Biel\\vc\\'\\ik; J. Biel\\vc\\'\\iková; A. Bilandzic; E. Biolcati; A. Blanc; F. Blanco; F. Blanco; D. Blau; C. Blume; M. Boccioli; N. Bock; A. Bogdanov; H. B\\oggild; M. Bogolyubsky; L. Boldizsár; M. Bombara; C. Bombonati; J. Book; H. Borel; C. Bortolin; S. Bose; F. Bossú; M. Botje; S. Böttger; B. Boyer; P. Braun-Munzinger; L. Bravina; M. Bregant; T. Breitner; M. Broz; R. Brun; E. Bruna; G. E. Bruno; D. Budnikov; H. Buesching; O. Busch; Z. Buthelezi; D. Caffarri; X. Cai; H. Caines; E. Calvo Villar; P. Camerini; V. Canoa Roman; G. Cara Romeo; F. Carena; W. Carena; F. Carminati; A. Casanova D\\'\\iaz; M. Caselle; J. Castillo Castellanos; V. Catanescu; C. Cavicchioli; P. Cerello; B. Chang; S. Chapeland; J. L. Charvet; S. Chattopadhyay; S. Chattopadhyay; M. Cherney; C. Cheshkov; B. Cheynis; E. Chiavassa; V. Chibante Barroso; D. D. Chinellato; P. Chochula; M. Chojnacki; P. Christakoglou; C. H. Christensen; P. Christiansen; T. Chujo; C. Cicalo; L. Cifarelli; F. Cindolo; J. Cleymans; F. Coccetti; J. -P. Coffin; S. Coli; G. Conesa Balbastre; Z. Conesa del Valle; P. Constantin; G. Contin; J. G. Contreras; T. M. Cormier; Y. Corrales Morales; I. Cortés Maldonado; P. Cortese; M. R. Cosentino; F. Costa; M. E. Cotallo; E. Crescio; P. Crochet; E. Cuautle; L. Cunqueiro; G. D Erasmo; A. Dainese; H. H. Dalsgaard; A. Danu; D. Das; I. Das; A. Dash; S. Dash; S. De; A. De Azevedo Moregula; G. O. V. de Barros; A. De Caro; G. de Cataldo; J. de Cuveland; A. De Falco; D. De Gruttola; N. De Marco; S. De Pasquale; R. De Remigis; R. de Rooij; H. Delagrange; Y. Delgado Mercado; G. Dellacasa; A. Deloff; V. Demanov; E. Dénes; A. Deppman; D. Di Bari; C. Di Giglio; S. Di Liberto; A. Di Mauro; P. Di Nezza; T. Dietel; R. Diviŕ; Ř. Djuvsland; A. Dobrin; T. Dobrowolski; I. Dom\\'\\inguez; B. Dönigus; O. Dordic; O. Driga; A. K. Dubey; L. Ducroux; P. Dupieux; A. K. Dutta Majumdar; M. R. Dutta Majumdar; D. Elia; D. Emschermann; H. Engel; H. A. Erdal; B. Espagnon; M. Estienne; S. Esumi; D. Evans; S. Evrard; G. Eyyubova; C. W. Fabjan; D. Fabris; J. Faivre; D. Falchieri; A. Fantoni; M. Fasel; R. Fearick; A. Fedunov; D. Fehlker; V. Fekete; D. Felea; G. Feofilov; A. Fernández Téllez; A. Ferretti; R. Ferretti; M. A. S. Figueredo; S. Filchagin; R. Fini; D. Finogeev; F. M. Fionda; E. M. Fiore; M. Floris; S. Foertsch; P. Foka; S. Fokin; E. Fragiacomo; M. Fragkiadakis; U. Frankenfeld; U. Fuchs; F. Furano; C. Furget; M. Fusco Girard; J. J. Gaardh\\oje; S. Gadrat; M. Gagliardi; A. Gago; M. Gallio; P. Ganoti; C. Garabatos; R. Gemme; J. Gerhard; M. Germain; C. Geuna; A. Gheata; M. Gheata; B. Ghidini; P. Ghosh; M. R. Girard; G. Giraudo; P. Giubellino; E. Gladysz-Dziadus; P. Glässel; R. Gomez; L. H. González-Trueba; P. González-Zamora; H. González Santos; S. Gorbunov; S. Gotovac; V. Grabski; R. Grajcarek; A. Grelli; A. Grigoras; C. Grigoras; V. Grigoriev; A. Grigoryan; S. Grigoryan; B. Grinyov; N. Grion; P. Gros; J. F. Grosse-Oetringhaus; J. -Y. Grossiord; R. Grosso; F. Guber; R. Guernane; C. Guerra Gutierrez; B. Guerzoni; K. Gulbrandsen; H. Gulkanyan; T. Gunji; A. Gupta; R. Gupta; H. Gutbrod; Ř. Haaland; C. Hadjidakis; M. Haiduc; H. Hamagaki; G. Hamar; J. W. Harris; M. Hartig; D. Hasch; D. Hasegan; D. Hatzifotiadou; A. Hayrapetyan; M. Heide; M. Heinz; H. Helstrup; A. Herghelegiu; C. Hernández; G. Herrera Corral; N. Herrmann; K. F. Hetland; B. Hicks; P. T. Hille; B. Hippolyte; T. Horaguchi; Y. Hori; P. Hristov; I. H\\vrivná\\vcová; M. Huang; S. Huber; T. J. Humanic; D. S. Hwang; R. Ichou; R. Ilkaev; I. Ilkiv; M. Inaba; E. Incani; G. M. Innocenti; P. G. Innocenti; M. Ippolitov; M. Irfan; C. Ivan; A. Ivanov; M. Ivanov; V. Ivanov; A. Jacho\\lkowski; P. M. Jacobs; L. Jancurová

2011-02-04T23:59:59.000Z

244

Nuclear Engineer (Nuclear Safety Specialist)  

Broader source: Energy.gov [DOE]

A successful candidate of this position will serve as a Nuclear Engineer (Nuclear Safety Specialist) responsible for day-to-day technical monitoring, and evaluation of aspects of authorization...

245

Nuclear spectroscopic studies  

SciTech Connect (OSTI)

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.

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

1993-02-08T23:59:59.000Z

246

Jets and dijets in Au+Au and p+p collisions at RHIC  

SciTech Connect (OSTI)

Recent data from RHIC suggest novel nuclear effects in the production of high p{sub T} hadrons. We present results from the STAR detector on high p{sub T} angular correlations in Au+Au and p+p collisions at {radical}S = 200 GeV/c. These two-particle angular correlation measurements verify the presence of a partonic hard scattering and fragmentation component at high p{sub T} in both central and peripheral Au+Au collisions. When triggering on a leading hadron with p{sub T}>4 GeV, we observe a quantitative agreement between the jet cone properties in p+p and all centralities of Au+Au collisions. This quantitative agreement indicates that nearly all hadrons with p{sub T}>4 GeV/c come from jet fragmentation and that jet fragmentation properties are not substantially modified in Au+Au collisions. STAR has also measured the strength of back-to-back high p{sub T} charged hadron correlations, and observes a small suppression of the back-to-back correlation strength in peripheral collisions, and a nearly complete disappearance o f back-to-back correlations in central Au+Au events. These phenomena, together with the observed strong suppression of inclusive yields and large value of elliptic flow at high p{sub T}, are consistent with a model where high p{sub T} hadrons come from partons created near the surface of the collision region, and where partons that originate or propagate towards the center of the collision region are substantially slowed or completely absorbed.

Hardtke, D.; STAR Collaboration

2002-12-09T23:59:59.000Z

247

$J/?$ suppression and $p_T$ spectra in RHIC and LHC energy collisions  

E-Print Network [OSTI]

In a hydrodynamic model, we have studied $J/\\psi$ production in Au+Au/Cu+Cu collisions at RHIC energy $\\sqrt{s}$=200 GeV. At the initial time, $J/\\psi$'s are randomly distributed in the fluid. As the fluid evolve in time, the free streaming $J/\\psi$'s are dissolved if the local fluid temperature exceeds a threshold temperature $T_{J/\\psi}$. Sequential melting of charmonium states ($\\chi_c$, $\\psi\\prime$ and $J/\\psi$), with melting temperatures $T_{\\chi_c}=T_{\\psi\\prime} \\approx 1.2T_c$, $T_{J/\\psi} \\approx2T_c$ and feed-down fraction $F\\approx 0.3$, explains the PHENIX data on the centrality dependence of $J/\\psi$ suppression in Au+Au collisions. $J/\\psi$ $p_T$ spectra and the nuclear modification factor in Au+Au collisions are also well explained in the model. The model however over predict centrality dependence of $J/\\psi$ suppression in Cu+Cu collisions by 20-30%. The $J/\\psi$ $p_T$ spectra are under predicted by 20-30%. The model predict that in central Pb+Pb collisions at LHC energy, $\\sqrt{s}$=5500 GeV, $J/\\psi$'s are suppressed by a factor of $\\sim$ 10. The model predicted $J/\\psi$ $p_T$ distribution in Pb+Pb collisions at LHC is similar to that in Au+Au collisions at RHIC.

A. K. Chaudhuri

2008-11-24T23:59:59.000Z

248

Energy Loss in Nuclear Drell-Yan Process  

E-Print Network [OSTI]

By means of the nuclear parton distributions which can be used to provide a good explanation for the EMC effect in the whole x range, we investigate the energy loss effect in nuclear Drell-Yan process. When the cross section of lepton pair production is considered varying with the center-of-mass energy of the nucleon-nucleon collision, we find that the nuclear Drell-Yan(DY) ratio is suppressed due to the energy loss, which balances the overestimate of the DY ratio only in consideration of the effect of nuclear parton distributions.

Jian-Jun Yang; Guang-Lie Li

1998-05-21T23:59:59.000Z

249

Low-coherent WDM reflectometry for accurate fiber length monitoring  

E-Print Network [OSTI]

A fiber-optic low-coherent reflectometer was developed to accurately monitor fiber length variation. A large length-coverage range was obtained by using a fiber Bragg grating array in a wavelength-division-multiplexing ...

Hui, Rongqing; Thomas, J.; Allen, Christopher Thomas; Fu, B.; Gao, S.

2003-01-01T23:59:59.000Z

250

Evolution of event-by-event ET fluctuations over collision centrality in RHIC interactions  

SciTech Connect (OSTI)

Preliminary results are presented for two analyses of transverse energy (ET) production measured with the electromagnetic calorimeters (EMC) of the Pioneering High Energy Nuclear Interaction Experiment (PHENIX), in relativistic nuclear interactions in Au+Au heavy-ion collisions created by the Relativistic Heavy Ion Collider (RHIC), at Brookhaven National Laboratory. Event-by-event ET distributions made across collision centrality were used in (1) measurements of 200 GeV , and (2) measurements of 200 GeV and 62.4 GeV ET distribution relative fluctuations {sigma}/ and {sigma}2/, where {sigma} is the standard deviation, and {sigma}2 the variance of each semi-inclusive distribution. Event centrality was selected in 5% wide bins and each bin represented by a modeled mean number of participant nucleons .

Armendariz, Raul [Department of Physics, New Mexico State University, Las Cruces, NM (United States)

2006-07-11T23:59:59.000Z

251

Dictionaries Using Variable-Length Keys and Data, with Applications *  

E-Print Network [OSTI]

(Isil- logn, 1) + Itil) and Isil is the length of bit string si. We assume a word length w > log m. We present string Isil > 1, Itil > 1 for all bit-strings si and ti. Fox' fixed-length keys the dictionary problem

Blelloch, Guy E.

252

$J/?$ production in Au+Au/Cu+Cu collisions at $\\sqrt{s}_{NN}$=200 GeV and the threshold model  

E-Print Network [OSTI]

Using the QGP motivated threshold model, where all the $J/\\psi$'s are suppressed above a threshold density, we have analyzed the preliminary PHENIX data on the centrality dependence of nuclear modification factor for $J/\\psi$'s in Cu+Cu and in Au+Au collisions, at RHIC energy, $\\sqrt{s}_{NN}$=200 GeV. Centrality dependence of $J/\\psi$ suppression in Au+Au collisions are well explained in the model for threshold densities in ranges of 3.6-3.7 $fm^{-2}$. $J/\\psi$ suppression in Cu+Cu collisions on the other hand are not explained in the model.

A. K. Chaudhuri

2006-10-09T23:59:59.000Z

253

Full jet reconstruction in 200 GeV p+p, d+Au and Au+Au collisions by STAR  

E-Print Network [OSTI]

Measurements of inclusive hadron suppression and di-hadron azimuthal correlations have provided important insights into jet quenching in hot QCD matter. However, they do not provide access to the energy of the hard scattering and are limited in their sensitivity since they can be affected by biases toward hard fragmentation and small energy loss. Full jet reconstruction in heavy-ion collisions enables a complete study of the modification of jet structure due to energy loss, but is challenging due to the high multiplicity environment. Study of jet production and properties in d+Au and p+p collisions provides important baseline measurement for jet studies in heavy-ion collisions. We report measurements of fully reconstructed jets in p+p, d+Au and Au+Au collisions at $\\sqrt{s_\\mathrm{NN}} = 200 \\mathrm{GeV}$ from the STAR experiment at RHIC. Measurement of initial state nuclear effects in d+Au collisions utilizing di-jet azimuthal correlations is presented together with similar measurement in p+p collisions. Inclusive jet $\\pt$ spectra and fragmentation functions in p+p and central Au+Au collisions are reported, with subsequent studies of jet nuclear modification factor, jet energy profile and modifications in the fragmentation function due to jet quenching.

Jan Kapitan; for the STAR Collaboration

2009-09-16T23:59:59.000Z

254

Energy transport through rare collisions  

E-Print Network [OSTI]

We study a one-dimensional hamiltonian chain of masses perturbed by an energy conserving noise. The dynamics is such that, according to its hamiltonian part, particles move freely in cells and interact with their neighbors through collisions, made possible by a small overlap of size $\\epsilon > 0$ between near cells. The noise only randomly flips the velocity of the particles. If $\\epsilon \\rightarrow 0$, and if time is rescaled by a factor $1/{\\epsilon}$, we show that energy evolves autonomously according to a stochastic equation, which hydrodynamic limit is known in some cases. In particular, if only two different energies are present, the limiting process coincides with the simple symmetric exclusion process.

François Huveneers

2011-07-14T23:59:59.000Z

255

Central collisions of heavy ions  

SciTech Connect (OSTI)

This report describes the activities of the Heavy Ion Physics Group at the University of California, Riverside from October 1, 1990 to September 30, 1991. During this period, our program focuses on particle production at AGS energies, and correlation studies at the Bevalac in nucleus central collisions. We participated in the preparation of letters of intent for two RHIC experiments -- the OASIS proposal and the Di-Muon proposal -- and worked on two RHIC R D efforts -- a silicon strip detector project and a muon-identifier project. A small fraction of time was also devoted to physics programs outside the realm of heavy ion reactions by several individuals.

Fung, Sun-yiu.

1991-10-01T23:59:59.000Z

256

Compact noninvasive electron bunch-length monitor  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

A compact rf cavity was constructed that simultaneously resonates at many harmonic modes when excited by a repetitive bunched electron beam passing through its bore. The excitation of these modes provides a Fourier description of the temporal characteristics of the bunch train. The cavity was used to noninvasively characterize electron bunches produced from thin and thick GaAs photocathodes inside a DC high voltage photogun illuminated with 37 ps (full width half maximum, FWHM) laser pulses at repetition rates near 1500 MHz, at average beam current from 5 to 500????A , and at beam energy from 75 to 195 keV. The cavity bunch-length monitor could detect electron bunches as short as 57 ps (FWHM) when connected directly to a sampling oscilloscope, and could clearly distinguish bunches with varying degrees of space-charge induced growth and with different tail signatures. Efforts are under way to detect shorter bunches by designing cavities with increased bandwidth. This demonstration lends credibility to the idea that these cavities could also be used for other applications, including bunching and shaping, when driven with external rf.

Roberts, B.; Mammei, R. R.; Poelker, M.; McCarter, J. L.

2012-12-01T23:59:59.000Z

257

RICE UNIVERSITY Ultracold Collisions in Atomic Strontium  

E-Print Network [OSTI]

RICE UNIVERSITY Ultracold Collisions in Atomic Strontium by Sarah B. Nagel A Thesis Submitted Houston, Texas February, 2008 #12;Abstract Ultracold Collisions in Atomic Strontium by Sarah B. Nagel In this work with atomic Strontium, the atoms are first laser cooled and subse- quently trapped, in a MOT

Killian, Thomas C.

258

Iron Air collision with high density QCD  

E-Print Network [OSTI]

The color glass condensate approach describes successfully heavy ion collisions at RHIC. We investigate Iron-air collisions within this approach and compare results to event generators commonly used in air shower simulations. We estimate uncertainties in the extrapolation to GZK energies and discuss implications for air shower simulations.

Hans-Joachim Drescher

2006-12-08T23:59:59.000Z

259

Energy flow observables in hadronic collisions  

E-Print Network [OSTI]

We present recent QCD calculations of energy flow distributions associated with the production of jets at wide rapidity separations in high-energy hadron collisions, and discuss the role of these observables to analyze contributions from parton showering and from multiple parton collisions.

F. Hautmann

2012-05-24T23:59:59.000Z

260

Precision neutron interferometric measurement of the nd coherent neutron scattering length and consequences for models of three-nucleon forces  

E-Print Network [OSTI]

We have performed the first high precision measurement of the coherent neutron scattering length of deuterium in a pure sample using neutron interferometry. We find b_nd = (6.665 +/- 0.004) fm in agreement with the world average of previous measurements using different techniques, b_nd = (6.6730 +/- 0.0045) fm. We compare the new world average for the nd coherent scattering length b_nd = (6.669 +/- 0.003) fm to calculations of the doublet and quartet scattering lengths from several modern nucleon-nucleon potential models with three-nucleon force (3NF) additions and show that almost all theories are in serious disagreement with experiment. This comparison is a more stringent test of the models than past comparisons with the less precisely-determined nuclear doublet scattering length of a_nd = (0.65 +/- 0.04) fm.

T. C. Black; P. R. Huffman; D. L. Jacobson; W. M. Snow; K. Schoen; M. Arif; H. Kaiser; S. K. Lamoreaux; S. A. Werner

2003-05-21T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

On the accuracy of using Fokker Planck equation in heavy ion collision  

E-Print Network [OSTI]

Application of Fokker-Planck equation to heavy quark transport in the evolving medium created in heavy ion collision is critically scrutinised. We realise that the approach introduces a moderate uncertainty in drag and diffusion coefficients culminating in huge ambiguity in the theoretical prediction of nuclear modification factor $R_{AA}$. Quantitative estimation of the error is presented by considering recent developments in this field.

Dutta, Nirupam

2015-01-01T23:59:59.000Z

262

Diagnostics of quark-gluon plasma in ultrarelativistic heavy ion collisions by hard QCD-processes  

E-Print Network [OSTI]

We analyze the possibilities for studying properties of dense QCD-matter, created in ultrarelativistic nuclear collisions, by hard QCD-production processes, so-called "hard" probes -- heavy quarkonia, hard jets, high mass dimuons. Special attention is paid to the potential of coming heavy ion experiments on Large Hadron Collider to observe the rescattering and energy losses of hard partons in quark-gluon plasma.

I. P. Lokhtin

2000-12-01T23:59:59.000Z

263

Fragile Signs of Criticality in the Nuclear Multifragmentation  

E-Print Network [OSTI]

Deviations from an idealized equilibrium phase transition picture in nuclear multifragmentation is studied in terms of the entropic index. We investigate different heat-capacity features in the canonical quantum statistical model of nuclear multifragmentation generalized in the framework of Tsallis nonextensive thermostatistics. We find that the negative branch of heat capacity observed in quasi-peripheral Au+Au collisions is caused primarily by the non-generic nonextensivity effects.

K. K. Gudima; M. Ploszajczak; V. D. Toneev

2001-06-08T23:59:59.000Z

264

Nuclear Structure and Dynamics from the Fully Unrestricted Skyrme-Hartree-Fock  

E-Print Network [OSTI]

and friendly environment in which to study nuclear physics. Special mention goes to my fellow theoristsNuclear Structure and Dynamics from the Fully Unrestricted Skyrme-Hartree-Fock Model A thesis performed for 16 O + 16 O and 28 Si + 16 O collisions at a variety of centre-of-mass energies and impact

Stevenson, Paul

265

Nuclear Counterterrorism  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

The Order defines requirements for the protection of sensitive improvised nuclear device information and provides a framework to support DOE activities related to nuclear counterterrorism. (A supplemental DOE Manual, Control of and Access to Improvised Nuclear Device Information, provides requirements and procedures for protecting Sigma 20 information.) Appendices A and B are Official Use Only. Point of contact is Adam Boyd (NA-82), 202-586-0010. Cancels DOE O 457.1 and DOE M 457.1-1.

2013-08-26T23:59:59.000Z

266

Measurement of beauty-hadron decay electrons in Pb--Pb collisions at sqrt(s_NN) = 2.76 TeV with ALICE  

E-Print Network [OSTI]

The ALICE Collaboration at the LHC studies heavy-ion collisions to investigate the properties of the Quark-Gluon Plasma (QGP). Heavy quarks (charm and beauty) are effective probes for this purpose. Both their energy loss in the medium as well as their possible thermalization yield information about the medium properties. Experimentally, the reconstruction of hadrons with charm valence quarks is possible. For hadrons with beauty valence quarks a promising strategy is the measurement of their decay electrons. To separate these from the background electrons (mainly from charm hadron decays, photon conversions or light-meson decays) the large decay length of beauty hadrons can be utilized. It leads to a relatively large typical impact parameter of the decay electrons. By comparing the impact parameter distribution of the signal electrons with those from the background sources, the signal can be statistically separated from the background. For this purpose a maximum likelihood fit is employed using impact parameter distribution templates from simulations. The resulting nuclear modification factor for electrons from beauty-hadron decays shows a sizeable suppression for p_T > 3 GeV, albeit still with large uncertainties.

Martin Völkl; for the ALICE Collaboration

2014-12-08T23:59:59.000Z

267

Simulating Collisions for Hydrokinetic Turbines  

SciTech Connect (OSTI)

Evaluations of blade-strike on an axial-flow Marine Hydrokinetic turbine were conducted using a conventional methodology as well as an alternative modeling approach proposed in the present document. The proposed methodology integrates the following components into a Computa- tional Fluid Dynamics (CFD) model: (i) advanced eddy-resolving flow simulations, (ii) ambient turbulence based on field data, (iii) moving turbine blades in highly transient flows, and (iv) Lagrangian particles to mimic the potential fish pathways. The sensitivity of blade-strike prob- ability to the following conditions was also evaluated: (i) to the turbulent environment, (ii) to fish size and (iii) to mean stream flow velocity. The proposed methodology provided fraction of collisions and offered the capability of analyzing the causal relationships between the flow envi- ronment and resulting strikes on rotating blades. Overall, the conventional methodology largely overestimates the probability of strike, and lacks the ability to produce potential fish and aquatic biota trajectories as they interact with the rotating turbine. By using a set of experimental corre- lations of exposure-response of living fish colliding on moving blades, the occurrence, frequency and intensity of the particle collisions was next used to calculate the survival rate of fish crossing the MHK turbine. This step indicated survival rates always greater than 98%. Although the proposed CFD framework is computationally more expensive, it provides the advantage of evaluating multiple mechanisms of stress and injury of hydrokinetic turbine devices on fish.

Richmond, Marshall C.; Romero Gomez, Pedro DJ; Rakowski, Cynthia L.

2013-10-01T23:59:59.000Z

268

nuclear controls  

National Nuclear Security Administration (NNSA)

the Office of Nonproliferation and International Security (NIS) is to prevent the proliferation of nuclear weapons, materials, technology, and expertise. NIS applies technical...

269

Critical Temperature for the Nuclear Liquid-Gas Phase Transition  

E-Print Network [OSTI]

The charge distribution of the intermediate mass fragments produced in p (8.1 GeV) + Au collisions is analyzed in the framework of the statistical multifragmentation model with the critical temperature for the nuclear liquid-gas phase transition $T_c$ as a free parameter. It is found that $T_c=20\\pm3$ MeV (90% CL).

V. A. Karnaukhov; H. Oeschler; S. P. Avdeyev; E. V. Duginova; V. K. Rodionov; A. Budzanowski; W. Karcz; O. V. Bochkarev; E. A. Kuzmin; L. V. Chulkov; E. Norbeck; A. S. Botvina

2003-02-07T23:59:59.000Z

270

Isospin dependent properties of asymmetric nuclear matter  

SciTech Connect (OSTI)

The density dependence of nuclear symmetry energy is determined from a systematic study of the isospin dependent bulk properties of asymmetric nuclear matter using the isoscalar and isovector components of the density dependent M3Y interaction. The incompressibility K{sub {infinity}} for the symmetric nuclear matter, the isospin dependent part K{sub asy} of the isobaric incompressibility, and the slope L are all in excellent agreement with the constraints recently extracted from measured isotopic dependence of the giant monopole resonances in even-A Sn isotopes, from the neutron skin thickness of nuclei, and from analyses of experimental data on isospin diffusion and isotopic scaling in intermediate energy heavy-ion collisions. This work provides a fundamental basis for the understanding of nuclear matter under extreme conditions and validates the important empirical constraints obtained from recent experimental data.

Chowdhury, P. Roy [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata 700 064 (India); Basu, D. N. [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700 064 (India); Samanta, C. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata 700 064 (India); Physics Department, Virginia Commonwealth University, Richmond, Virginia 232840 (United States); Physics Department, University of Richmond, Virginia 23173 (United States)

2009-07-15T23:59:59.000Z

271

Isospin dependent properties of asymmetric nuclear matter  

E-Print Network [OSTI]

The density dependence of nuclear symmetry energy is determined from a systematic study of the isospin dependent bulk properties of asymmetric nuclear matter using the isoscalar and the isovector components of density dependent M3Y interaction. The incompressibility $K_\\infty$ for the symmetric nuclear matter, the isospin dependent part $K_{asy}$ of the isobaric incompressibility and the slope $L$ are all in excellent agreement with the constraints recently extracted from measured isotopic dependence of the giant monopole resonances in even-A Sn isotopes, from the neutron skin thickness of nuclei and from analyses of experimental data on isospin diffusion and isotopic scaling in intermediate energy heavy-ion collisions. This work provides a fundamental basis for the understanding of nuclear matter under extreme conditions, and validates the important empirical constraints obtained from recent experimental data.

P. Roy Chowdhury; D. N. Basu; C. Samanta

2009-07-15T23:59:59.000Z

272

Feshbach resonances and transition rates for cold homonuclear collisions between {sup 39}K and {sup 41}K atoms  

SciTech Connect (OSTI)

We report results from close-coupling calculations for homonuclear ultracold collisions between potassium atoms, using the most up-to-date Born-Oppenheimer potential curves. The present study includes both of the bosonic isotopes {sup 39}K and {sup 41}K. The s-wave scattering lengths as functions of the magnetic field strength for collisions between atoms in identical and different hyperfine states are obtained. Several Feshbach resonances are located and characterized for both isotopes. Comparison with experiments, where such data are available, show excellent agreement. We also study weakly bound molecular states of the K{sub 2} molecule in close relation to the calculated Feshbach resonances. Another objective of the present work is to study inelastic collisions in which the hyperfine states of the colliding atoms are changed. From this type of calculation we obtain transition rates as functions of the magnetic field strength. Finally, we discuss how such transition rates might be of importance for experimental work.

Lysebo, M.; Veseth, L. [Department of Physics, University of Oslo, N-0316 Oslo (Norway)

2010-03-15T23:59:59.000Z

273

Blast of light fragments from central heavy-ion collisions  

SciTech Connect (OSTI)

The effects of collective expansion on light-fragment emission from central heavy-ion collisions are studied by carrying out calculations in a transport model with dynamic production of {ital A}{le}3 fragments. Beam energies of few hundred MeV/nucleon are considered. In the simulations the formation of a region of dense excited nuclear matter is observed, which expands in transverse directions. The expansion is reflected in the angular distributions and in the mean transverse energies of emitted fragments. At the late stage of expansion the characteristic features of local thermodynamic equilibrium are identified. Different particles share nearly the same collective energy per nucleon, and nearly the same thermal energy. The calculated mean transverse energies of the fragments reflect the collective energy whose magnitude varies with impact parameter. However, the fragment energies only partially agree with available data. The calculated spectra exhibit different slopes at angles around c.m. 90{degree} in central reactions.

Danielewicz, P.; Pan, Q. (National Superconducting Cyclotron Laboratory, and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States))

1992-11-01T23:59:59.000Z

274

Nuclear Astrophysics  

E-Print Network [OSTI]

Nuclear physics has a long and productive history of application to astrophysics which continues today. Advances in the accuracy and breadth of astrophysical data and theory drive the need for better experimental and theoretical understanding of the underlying nuclear physics. This paper will review some of the scenarios where nuclear physics plays an important role, including Big Bang Nucleosynthesis, neutrino production by our sun, nucleosynthesis in novae, the creation of elements heavier than iron, and neutron stars. Big-bang nucleosynthesis is concerned with the formation of elements with A nuclear physics inputs required are few-nucleon reaction cross sections. The nucleosynthesis of heavier elements involves a variety of proton-, alpha-, neutron-, and photon-induced reactions, coupled with radioactive decay. The advent of radioactive ion beam facilities has opened an important new avenue for studying these processes, as many involve radioactive species. Nuclear physics also plays an important role in neutron stars: both the nuclear equation of state and cooling processes involving neutrino emission play a very important role. Recent developments and also the interplay between nuclear physics and astrophysics will be highlighted.

Carl R. Brune

2005-02-28T23:59:59.000Z

275

SQUID magnetometry from nanometer to centimeter length scales  

E-Print Network [OSTI]

length scales . . . . . . . Josephson Junction and SQUIDin nanoscale weak link josephson junction oscillators. Phys.cation by unbiased Josephson junctions. Journ. Appl. Phys. ,

Hatridge, Michael Jonathan

2010-01-01T23:59:59.000Z

276

Structuring Materials on Multiple Length Scales for Energy Application...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Structuring Materials on Multiple Length Scales for Energy Applications October 25, 2012 at 3pm36-428 Adreas Stein Department of Chemistry, University of Minnesota astein...

277

Chemistry-nuclear chemistry division. Progress report, October 1979-September 1980  

SciTech Connect (OSTI)

This report presents the research and development programs pursued by the Chemistry-Nuclear Chemistry Division of the Los Alamos National Laboratory. Topics covered include advanced analytical methods, atmospheric chemistry and transport, biochemistry, biomedical research, element migration and fixation, inorganic chemistry, isotope separation and analysis, atomic and molecular collisions, molecular spectroscopy, muonic x rays, nuclear cosmochemistry, nuclear structure and reactions, radiochemical separations, theoretical chemistry, and unclassified weapons research.

Ryan, R.R. (comp.)

1981-05-01T23:59:59.000Z

278

Nuclear matter equation of state from relativistic heavy ions to supernovae  

SciTech Connect (OSTI)

In this presentation the relationship between relativistic nucleus-nucleus collisions and the nuclear equation of state is discussed. The connection between observables measured in the experiments and thermodynamic variables used to describe the system is made. Through this connection a semi-empirical nuclear equation of state is extracted from the data. The resulting equation of state is discussed in terms of nuclear matter calculations, neutron star stability and supernova collapse. 22 refs., 7 figs.

Harris, J.W.

1986-06-01T23:59:59.000Z

279

Nuclear Counterterrorism  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

The Order defines requirements for the protection of sensitive improvised nuclear device information and provides a framework to support DOE activities related to nuclear counterterrorism. (A supplemental DOE Manual, Control of and Access to Improvised Nuclear Device Information, provides requirements and procedures for protecting Sigma 20 information. The Manual is Official Use Only, and is not available on the Directives Portal. The point of contact for the Manual is Randall Weidman, NA-121.2, 202-586-4582.) Canceled by DOE O 457.1A

2006-02-07T23:59:59.000Z

280

Countering Nuclear Terrorism and Trafficking | National Nuclear...  

National Nuclear Security Administration (NNSA)

Countering Nuclear Terrorism and Trafficking | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing...

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Partonic coalescence in relativistic heavy ion collisions  

E-Print Network [OSTI]

Using a covariant coalescence model, we study hadron production in relativistic heavy ion collisions from both soft partons in the quark-gluon plasma and hard partons in minijets. Including transverse flow of soft partons and independent...

Greco, V.; Ko, Che Ming; Levai, P.

2003-01-01T23:59:59.000Z

282

Physics in Collision 2009 -- Kobe, Japan  

ScienceCinema (OSTI)

Dr. Yuji Yamazaki, a host of the Physics in Collision 2009 conference, and Dr. Thomas Muller, who will host the conference in 2010, talk about PIC 2009 in Kobe, Japan.

Dr. Yuji Yamazaki

2010-01-08T23:59:59.000Z

283

Coulomb collision effects on linear Landau damping  

SciTech Connect (OSTI)

Coulomb collisions at rate ? produce slightly probabilistic rather than fully deterministic charged particle trajectories in weakly collisional plasmas. Their diffusive velocity scattering effects on the response to a wave yield an effective collision rate ?{sub eff} ? ? and a narrow dissipative boundary layer for particles with velocities near the wave phase velocity. These dissipative effects produce temporal irreversibility for times t???1/?{sub eff} during Landau damping of a small amplitude Langmuir wave.

Callen, J. D., E-mail: callen@engr.wisc.edu [University of Wisconsin, Madison, Wisconsin 53706-1609 (United States)

2014-05-15T23:59:59.000Z

284

NUCLEAR PLANT OPERATIONS AND  

E-Print Network [OSTI]

NUCLEAR PLANT OPERATIONS AND CONTROL KEYWORDS: neutron flux, cur- rent noise, vibration diagnostics: Swedish Nuclear Powe

Pázsit, Imre

285

Space Nuclear  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Space Nuclear Today the INL is preparing to assist with the Multi-Mission RTG (MMRTG). The INL is assigned the final assembly and testing of the RTG for the project which is...

286

Nuclear Golf  

E-Print Network [OSTI]

Broadcast Transcript: Pay no attention to that nuclear warhead behind the 18th hole; just shout "Fore!" and drive your Titleist down the fairway. In a development that is bizarre even by North Korean standards, the country ...

Hacker, Randi; Tsutsui, William

2006-12-06T23:59:59.000Z

287

Nuclear Hydrogen  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Hydrogen High temperature options for nuclear generation of hydrogen on a commercial basis are several years in the future. Thermo-chemical water splitting has been proven to be...

288

Nuclear forces  

SciTech Connect (OSTI)

These lectures present an introduction into the theory of nuclear forces. We focus mainly on the modern approach, in which the forces between nucleons emerge from low-energy QCD via chiral effective field theory.

Machleidt, R. [Department of Physics, University of Idaho, Moscow, Idaho 83844 (United States)

2013-06-10T23:59:59.000Z

289

Sighting optics including an optical element having a first focal length and a second focal length and methods for sighting  

DOE Patents [OSTI]

Sighting optics include a front sight and a rear sight positioned in a spaced-apart relation. The rear sight includes an optical element having a first focal length and a second focal length. The first focal length is selected so that it is about equal to a distance separating the optical element and the front sight and the second focal length is selected so that it is about equal to a target distance. The optical element thus brings into simultaneous focus for a user images of the front sight and the target.

Crandall, David Lynn

2011-08-16T23:59:59.000Z

290

EMC effect and jet energy loss in relativistic deuteron-nucleus collisions  

E-Print Network [OSTI]

We investigate the influence of modified nuclear parton distribution functions (PDFs) on high-pT hadron production at RHIC and LHC energies using a pQCD-improved parton model. For application at RHIC, we focus on the possible contribution of the EMC modification of the nuclear PDFs in the x > 0.3 region to the observed suppression of pi0 production at pT > 10 GeV/c in dAu collisions. We study three different parameterizations of the nuclear PDF modifications and find that they give consistent results for R_dAu(pT) for neutral pions in the region 10 GeV/c EMC suppression of the parton distributions in the Au nucleus does not strongly influence the R_dAu for pi0 in the pT region where the suppression is observed. Using the HKN parameterization, we evaluate systematic errors in the theoretical R_dAu(pT) resulting from uncertainties in the nuclear PDFs. The measured nuclear modification factor is inconsistent with the pQCD model result for pT > 10 GeV/c even when the systematic uncertainties in the nuclear PDFs are accounted for. The inclusion of a small final-state energy loss can reduce the discrepancy with the data, but we cannot perfectly reproduce the pT dependence of the measured R_dAu(pT). For the LHC, we find that shadowing of the nuclear PDFs produces a large suppression in the yield of hadrons with pT < 100 GeV/c in p(d)A collisions.

B. A. Cole; G. G. Barnafoldi; P. Levai; G. Papp; G. Fai

2007-02-09T23:59:59.000Z

291

Forward hadron production in ultraperipheral proton-heavy-ion collisions at the LHC and RHIC  

E-Print Network [OSTI]

We discuss hadron production in the forward rapidity region in ultraperipheral proton-lead collisions at the LHC and proton-gold collisions at RHIC. Our discussion is based on the Monte Carlo simulations of the interactions of virtual photons emitted by a fast moving nucleus with a proton beam. We simulate the virtual photon flux with the STARLIGHT event generator and then particle production with the SOPHIA, DPMJET, and PYTHIA event generators. We show the rapidity distributions of charged and neutral particles, and the momentum distributions of neutral pions and neutrons at forward rapidities. According to the Monte Carlo simulations, we find large cross sections of ultraperipheral collisions for particle production especially in the very forward region, leading to substantial background contributions to investigations of collective nuclear effects and spin physics. Finally we can distinguish between proton-nucleus inelastic interactions and ultraperipheral collisions with additional requirements of either of the charged particles at midrapidity and a certain level of activities at negative forward rapidity.

Gaku Mitsuka

2015-03-12T23:59:59.000Z

292

On Termination and Derivation Lengths for Ground Rewrite Systems  

E-Print Network [OSTI]

On Termination and Derivation Lengths for Ground Rewrite Systems Dieter Hofbauer 1 Universit¨at GH@theory.informatik.uni­kassel.de Abstract. It is shown that for terminating ground term rewrite systems the length of derivations a suitable interpretation into the natural numbers. Terminating ground systems are not necessarily

Giesl, Juergen

293

Explanation of the Random Lengths Framing Lumber Composite Price  

E-Print Network [OSTI]

Explanation of the Random Lengths Framing Lumber Composite Price May 10, 2006 The Random Lengths Framing Lumber Composite is a broad measure of price behavior in the U.S. framing lumber market) Western U.S., 2) Southern U.S., and 3) Canada. Thus, 33% of the Composite is comprised of Southern Pine

294

Scaling of fracture length and distributed damage Vladimir Lyakhovsky  

E-Print Network [OSTI]

Scaling of fracture length and distributed damage Vladimir Lyakhovsky The Institute of Earth space scaling except linear relations between fracture length and displacements and thus the determination theoretically of the strength of a body or structure directly. Self-similarity of a fracture

Lyakhovsky, Vladimir

295

A Study of Query Length Avi Arampatzis1  

E-Print Network [OSTI]

length, and fit power-law and Poisson distribu- tions to four different query sets. We provide and a power-law distribution for longer queries, that better fits real query length distributions than earlier proposals. Categories and Subject Descriptors: H.3 [Information Storage and Re- trieval]: H.3.3 Information

Arampatzis, Avi

296

Chemistry-Nuclear Chemistry Division. Progress report, October 1980-September 1981  

SciTech Connect (OSTI)

This report describes major progress in the research and development programs pursued by the Chemistry-Nuclear Chemistry Division of the Los Alamos National Laboratory during FY 1981. Topics covered include advanced analytical methods, atmospheric chemistry and transport, biochemistry, biomedical research, medical radioisotopes research, element migration and fixation, nuclear waste isolation research, inorganic and structural chemistry, isotope separation, analysis and applications, the newly established Nuclear Magnetic Resonance Center, atomic and molecular collisions, molecular spectroscopy, nuclear cosmochemistry, nuclear structure and reactions, pion charge exchange, radiochemical separations, theoretical chemistry, and unclassified weapons research.

Ryan, R.R. (comp.)

1982-05-01T23:59:59.000Z

297

Nuclear reactor safety device  

DOE Patents [OSTI]

A safety device is disclosed for use in a nuclear reactor for axially repositioning a control rod with respect to the reactor core in the event of an upward thermal excursion. Such safety device comprises a laminated helical ribbon configured as a tube-like helical coil having contiguous helical turns with slidably abutting edges. The helical coil is disclosed as a portion of a drive member connected axially to the control rod. The laminated ribbon is formed of outer and inner laminae. The material of the outer lamina has a greater thermal coefficient of expansion than the material of the inner lamina. In the event of an upward thermal excursion, the laminated helical coil curls inwardly to a smaller diameter. Such inward curling causes the total length of the helical coil to increase by a substantial increment, so that the control rod is axially repositioned by a corresponding amount to reduce the power output of the reactor.

Hutter, Ernest (Wilmette, IL)

1986-01-01T23:59:59.000Z

298

J/{psi} Production in {radical}(s{sub NN})=200 GeV Cu+Cu Collisions  

SciTech Connect (OSTI)

Yields for J/{psi} production in Cu+Cu collisions at {radical}(s{sub NN})=200 GeV have been measured over the rapidity range |y|<2.2 and compared with results in p+p and Au+Au collisions at the same energy. The Cu+Cu data offer greatly improved precision over existing Au+Au data for J/{psi} production in collisions with small to intermediate numbers of participants, in the range where the quark-gluon plasma transition threshold is predicted to lie. Cold nuclear matter estimates based on ad hoc fits to d+Au data describe the Cu+Cu data up to N{sub part}{approx}50, corresponding to a Bjorken energy density of at least 1.5 GeV/fm{sup 3}.

Adare, A.; Bickley, A. A.; Ellinghaus, F.; Glenn, A.; Kinney, E.; Nagle, J. L.; Seele, J.; Wysocki, M. [University of Colorado, Boulder, Colorado 80309 (United States); Afanasiev, S.; Isupov, A.; Litvinenko, A.; Malakhov, A.; Peresedov, V.; Rukoyatkin, P.; Zolin, L. [Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region (Russian Federation); Aidala, C.; Chi, C. Y.; Cole, B. A.; D'Enterria, D.; Jia, J. [Columbia University, New York, New York 10027 and Nevis Laboratories, Irvington, New York 10533 (United States)] (and others)

2008-09-19T23:59:59.000Z

299

Scaling Properties of Hyperon Production in Au + Au Collisions at sqrt sNN = 200 GeV  

SciTech Connect (OSTI)

We present the scaling properties of Lambda, Xi, and their anti-particles produced at mid-rapidity in Au+Au collisions at RHIC at psNN = 200 GeV. The yield of multi-strange baryons per participant nucleon increases from peripheral to central collisions more rapidly than the Lambda yield, which appears to correspond to an increasing strange quark density of matter produced. The value of the strange phase space occupancy factor gamma s, obtained from a thermal model fit to the data, approaches unity for the most central collisions. We also show that the nuclear modification factors, RCP, of Lambda and Xi are consistent with each other and with that of protons in the transverse momentum range2.0< pT< 5.0 GeV/c. This scaling behaviour is consistent with a scenario of hadron formation from constituent quark degrees of freedom through quark recombination or coalescence.

Adams, J.

2006-06-08T23:59:59.000Z

300

Suppression of high transverse momentum D mesons in central Pb--Pb collisions at $\\sqrt{s_{NN}}=2.76$ TeV  

E-Print Network [OSTI]

The production of the prompt charm mesons $D^0$, $D^+$, $D^{*+}$, and their antiparticles, was measured with the ALICE detector in Pb-Pb collisions at the LHC, at a centre-of-mass energy $\\sqrt{s_{NN}}=2.76$ TeV per nucleon--nucleon collision. The $\\pt$-differential production yields in the range $2nuclear modification factor $R_{AA}$ with respect to a proton-proton reference obtained from the cross section measured at $\\sqrt{s}=7$ TeV and scaled to $\\sqrt{s}=2.76$ TeV. For the three meson species, $R_{AA}$ shows a suppression by a factor 3-4, for transverse momenta larger than 5 GeV/c in the 20% most central collisions. The suppression is reduced for peripheral collisions.

ALICE Collaboration; B. Abelev; J. Adam; D. Adamová; A. M. Adare; M. M. Aggarwal; G. Aglieri Rinella; A. G. Agocs; A. Agostinelli; S. Aguilar Salazar; Z. Ahammed; N. Ahmad; A. Ahmad Masoodi; S. U. Ahn; A. Akindinov; D. Aleksandrov; B. Alessandro; R. Alfaro Molina; A. Alici; A. Alkin; E. Almaráz Avińa; J. Alme; T. Alt; V. Altini; S. Altinpinar; I. Altsybeev; C. Andrei; A. Andronic; V. Anguelov; J. Anielski; C. Anson; T. Anticic; F. Antinori; P. Antonioli; L. Aphecetche; H. Appelshäuser; N. Arbor; S. Arcelli; A. Arend; N. Armesto; R. Arnaldi; T. Aronsson; I. C. Arsene; M. Arslandok; A. Asryan; A. Augustinus; R. Averbeck; T. C. Awes; J. Äystö; M. D. Azmi; M. Bach; A. Badalŕ; Y. W. Baek; R. Bailhache; R. Bala; R. Baldini Ferroli; A. Baldisseri; A. Baldit; F. Baltasar Dos Santos Pedrosa; J. Bán; R. C. Baral; R. Barbera; F. Barile; G. G. Barnaföldi; L. S. Barnby; V. Barret; J. Bartke; M. Basile; N. Bastid; S. Basu; B. Bathen; G. Batigne; B. Batyunya; C. Baumann; I. G. Bearden; H. Beck; I. Belikov; F. Bellini; R. Bellwied; E. Belmont-Moreno; G. Bencedi; S. Beole; I. Berceanu; A. Bercuci; Y. Berdnikov; D. Berenyi; D. Berzano; L. Betev; A. Bhasin; A. K. Bhati; J. Bhom; N. Bianchi; L. Bianchi; C. Bianchin; J. Bielcík; J. Bielcíková; A. Bilandzic; S. Bjelogrlic; F. Blanco; F. Blanco; D. Blau; C. Blume; M. Boccioli; N. Bock; A. Bogdanov; H. Břggild; M. Bogolyubsky; L. Boldizsár; M. Bombara; J. Book; H. Borel; A. Borissov; S. Bose; F. Bossú; M. Botje; S. Böttger; B. Boyer; E. Braidot; P. Braun-Munzinger; M. Bregant; T. Breitner; T. A. Browning; M. Broz; R. Brun; E. Bruna; G. E. Bruno; D. Budnikov; H. Buesching; S. Bufalino; K. Bugaiev; O. Busch; Z. Buthelezi; D. Caballero Orduna; D. Caffarri; X. Cai; H. Caines; E. Calvo Villar; P. Camerini; V. Canoa Roman; G. Cara Romeo; W. Carena; F. Carena; N. Carlin Filho; F. Carminati; C. A. Carrillo Montoya; A. Casanova Díaz; J. Castillo Castellanos; J. F. Castillo Hernandez; E. A. R. Casula; V. Catanescu; C. Cavicchioli; C. Ceballos Sanchez; J. Cepila; P. Cerello; B. Chang; S. Chapeland; J. L. Charvet; S. Chattopadhyay; S. Chattopadhyay; I. Chawla; M. Cherney; C. Cheshkov; B. Cheynis; V. Chibante Barroso; D. D. Chinellato; P. Chochula; M. Chojnacki; S. Choudhury; P. Christakoglou; C. H. Christensen; P. Christiansen; T. Chujo; S. U. Chung; C. Cicalo; L. Cifarelli; F. Cindolo; J. Cleymans; F. Coccetti; F. Colamaria; D. Colella; G. Conesa Balbastre; Z. Conesa del Valle; P. Constantin; G. Contin; J. G. Contreras; T. M. Cormier; Y. Corrales Morales; P. Cortese; I. Cortés Maldonado; M. R. Cosentino; F. Costa; M. E. Cotallo; E. Crescio; P. Crochet; E. Cruz Alaniz; E. Cuautle; L. Cunqueiro; A. Dainese; H. H. Dalsgaard; A. Danu; K. Das; I. Das; D. Das; A. Dash; S. Dash; S. De; G. O. V. de Barros; A. De Caro; G. de Cataldo; J. de Cuveland; A. De Falco; D. De Gruttola; H. Delagrange; E. Del Castillo Sanchez; A. Deloff; V. Demanov; N. De Marco; E. Dénes; S. De Pasquale; A. Deppman; G. D Erasmo; R. de Rooij; M. A. Diaz Corchero; D. Di Bari; T. Dietel; C. Di Giglio; S. Di Liberto; A. Di Mauro; P. Di Nezza; R. Diviŕ; Ř. Djuvsland; A. Dobrin; T. Dobrowolski; I. Domínguez; B. Dönigus; O. Dordic; O. Driga; A. K. Dubey; L. Ducroux; P. Dupieux; A. K. Dutta Majumdar; M. R. Dutta Majumdar; D. Elia; D. Emschermann; H. Engel; H. A. Erdal; B. Espagnon; M. Estienne; S. Esumi; D. Evans; G. Eyyubova; D. Fabris; J. Faivre; D. Falchieri; A. Fantoni; M. Fasel; R. Fearick; A. Fedunov; D. Fehlker; L. Feldkamp; D. Felea; B. Fenton-Olsen; G. Feofilov; A. Fernández Téllez; A. Ferretti; R. Ferretti; J. Figiel; M. A. S. Figueredo; S. Filchagin; D. Finogeev; F. M. Fionda; E. M. Fiore; M. Floris; S. Foertsch; P. Foka; S. Fokin; E. Fragiacomo; M. Fragkiadakis; U. Frankenfeld; U. Fuchs; C. Furget; M. Fusco Girard; J. J. Gaardhřje; M. Gagliardi; A. Gago; M. Gallio; D. R. Gangadharan; P. Ganoti; C. Garabatos; E. Garcia-Solis; I. Garishvili; J. Gerhard; M. Germain; C. Geuna; M. Gheata; A. Gheata; B. Ghidini; P. Ghosh; P. Gianotti; M. R. Girard; P. Giubellino; E. Gladysz-Dziadus; P. Glässel; R. Gomez; E. G. Ferreiro; L. H. González-Trueba; P. González-Zamora; S. Gorbunov; A. Goswami; S. Gotovac; V. Grabski; L. K. Graczykowski; R. Grajcarek; A. Grelli; C. Grigoras; A. Grigoras; V. Grigoriev; S. Grigoryan; A. Grigoryan; B. Grinyov; N. Grion; P. Gros; J. F. Grosse-Oetringhaus; J. -Y. Grossiord; R. Grosso; F. Guber; R. Guernane; C. Guerra Gutierrez; B. Guerzoni; M. Guilbaud; K. Gulbrandsen; T. Gunji; R. Gupta; A. Gupta; H. Gutbrod; Ř. Haaland; C. Hadjidakis; M. Haiduc; H. Hamagaki; G. Hamar; B. H. Han; L. D. Hanratty; A. Hansen; Z. Harmanova; J. W. Harris; M. Hartig; D. Hasegan; D. Hatzifotiadou; A. Hayrapetyan; S. T. Heckel; M. Heide; H. Helstrup; A. Herghelegiu; G. Herrera Corral; N. Herrmann; K. F. Hetland

2012-10-12T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
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301

Nuclear Science Division annual report, July 1, 1981-September 30, 1982  

SciTech Connect (OSTI)

This report summarizes the scientific research carried out within the Nuclear Science Division between July 1, 1981, and September 30, 1982. Heavy-ion investigations continue to dominate the experimental and theoretical research efforts. Complementary programs in light-ion nuclear science, in nuclear data evaluation, and in the development of advanced instrumentation are also carried out. Results from Bevalac experiments employing a wide variety of heavy ion beams, along with new or upgraded detector facilities (HISS, the Plastic Ball, and the streamer chamber) are contained in this report. These relativistic experiments have shed important light on the degree of equilibration for central collisions, the time evolution of a nuclear collision, the nuclear density and compressional energy of these collisions, and strange particle production. Reaction mechanism work dominates the heavy-ion research at the 88-Inch Cyclotron and the SuperHILAC. Recent experiments have contributed to our understanding of the nature of light-particle emission in deep-inelastic collisions, of peripheral reactions, incomplete fusion, fission, and evaporation. Nuclear structure investigations at these accelerators continue to be directed toward the understanding of the behavior of nuclei at high angular momentum. Research in the area of exotic nuclei has led to the observation at the 88-Inch Cyclotron of the ..beta..-delayed proton decay of odd-odd T/sub z/ = -2 nuclides; ..beta..-delayed proton emitters in the rare earth region are being investigated at the SuperHILAC.

Mahoney, J. (ed.)

1983-06-01T23:59:59.000Z

302

Portable 543 nm length standard and magnetic-induced zero-crossing shift on length standard transition  

E-Print Network [OSTI]

a convenient and objective length standard for use in both academic and industrial applications. Ever since the ve- locity of light in a vacuum was defined as 299 792 458 m/s in 1983,1 atom or molecule of the primary length-standard lasers,16 and some inter- comparisons were held thereafter.11,14 Therefore

Shy,Jow-Tsong

303

Suppression of Upsilon Production in d+Au and Au+Au Collisions at sqrt(s_NN) = 200 GeV  

E-Print Network [OSTI]

We report measurements of Upsilon meson production in p+p, d+Au, and Au+Au collisions using the STAR detector at RHIC. We compare the Upsilon yield to the measured cross section in p+p collisions in order to quantify any modifications of the yield in cold nuclear matter using d+Au data and in hot nuclear matter using Au+Au data separated into three centrality classes. Our p+p measurement is based on three times the statistics of our previous result. We obtain a nuclear modification factor for Upsilon(1S+2S+3S) in the rapidity range |y|<1 in d+Au collisions of R_dAu = 0.79 +/- 0.24 (stat.) +/- 0.03 (sys.) +/- 0.10 (pp sys.). A comparison with models including shadowing and initial state parton energy loss indicates the presence of additional cold-nuclear matter suppression. Similarly, in the top 10% most-central Au+Au collisions, we measure a nuclear modification factor of R_AA=0.49 +/- 0.1 (stat.) +/- 0.02 (sys.) +/- 0.06 (pp sys.), which is a larger suppression factor than that seen in cold nuclear matter. Our results are consistent with complete suppression of excited-state Upsilon mesons in Au+Au collisions. The additional suppression in Au+Au is consistent with the level expected in model calculations that include the presence of a hot, deconfined Quark-Gluon Plasma. However, understanding the suppression seen in d+Au is still needed before any definitive statements about the nature of the suppression in Au+Au can be made.

L. Adamczyk; J. K. Adkins; G. Agakishiev; M. M. Aggarwal; Z. Ahammed; I. Alekseev; J. Alford; C. D. Anson; A. Aparin; D. Arkhipkin; E. C. Aschenauer; G. S. Averichev; A. Banerjee; D. R. Beavis; R. Bellwied; A. Bhasin; A. K. Bhati; P. Bhattarai; H. Bichsel; J. Bielcik; J. Bielcikova; L. C. Bland; I. G. Bordyuzhin; W. Borowski; J. Bouchet; A. V. Brandin; S. G. Brovko; S. Bültmann; I. Bunzarov; T. P. Burton; J. Butterworth; H. Caines; M. Calderón de la Barca Sánchez; D. Cebra; R. Cendejas; M. C. Cervantes; P. Chaloupka; Z. Chang; S. Chattopadhyay; H. F. Chen; J. H. Chen; L. Chen; J. Cheng; M. Cherney; A. Chikanian; W. Christie; J. Chwastowski; M. J. M. Codrington; G. Contin; J. G. Cramer; H. J. Crawford; X. Cui; S. Das; A. Davila Leyva; L. C. De Silva; R. R. Debbe; T. G. Dedovich; J. Deng; A. A. Derevschikov; R. Derradi de Souza; S. Dhamija; B. di Ruzza; L. Didenko; C. Dilks; F. Ding; P. Djawotho; X. Dong; J. L. Drachenberg; J. E. Draper; C. M. Du; L. E. Dunkelberger; J. C. Dunlop; L. G. Efimov; J. Engelage; K. S. Engle; G. Eppley; L. Eun; O. Evdokimov; R. Fatemi; S. Fazio; J. Fedorisin; P. Filip; E. Finch; Y. Fisyak; C. E. Flores; C. A. Gagliardi; D. R. Gangadharan; D. Garand; F. Geurts; A. Gibson; M. Girard; S. Gliske; L. Greiner; D. Grosnick; Y. Guo; A. Gupta; S. Gupta; W. Guryn; B. Haag; O. Hajkova; A. Hamed; L-X. Han; R. Haque; J. W. Harris; S. Heppelmann; K. Hill; A. Hirsch; G. W. Hoffmann; D. J. Hofman; S. Horvat; B. Huang; H. Z. Huang; X. Huang; P. Huck; T. J. Humanic; G. Igo; W. W. Jacobs; H. Jang; E. G. Judd; S. Kabana; D. Kalinkin; K. Kang; K. Kauder; H. W. Ke; D. Keane; A. Kechechyan; A. Kesich; Z. H. Khan; D. P. Kikola; I. Kisel; A. Kisiel; D. D. Koetke; T. Kollegger; J. Konzer; I. Koralt; L. Kotchenda; P. Kravtsov; K. Krueger; I. Kulakov; L. Kumar; R. A. Kycia; M. A. C. Lamont; J. M. Landgraf; K. D. Landry; J. Lauret; A. Lebedev; R. Lednicky; J. H. Lee; M. J. LeVine; C. Li; W. Li; X. Li; X. Li; Y. Li; Z. M. Li; L. M. Lima; M. A. Lisa; F. Liu; T. Ljubicic; W. J. Llope; M. Lomnitz; R. S. Longacre; X. Luo; G. L. Ma; Y. G. Ma; D. M. M. D. Madagodagettige Don; D. P. Mahapatra; R. Majka; S. Margetis; C. Markert; H. Masui; H. S. Matis; D. McDonald; T. S. McShane; N. G. Minaev; S. Mioduszewski; B. Mohanty; M. M. Mondal; D. A. Morozov; M. G. Munhoz; M. K. Mustafa; B. K. Nandi; Md. Nasim; T. K. Nayak; J. M. Nelson; G. Nigmatkulov; L. V. Nogach; S. Y. Noh; J. Novak; S. B. Nurushev; G. Odyniec; A. Ogawa; K. Oh; A. Ohlson; V. Okorokov; E. W. Oldag; R. A. N. Oliveira; M. Pachr; B. S. Page; S. K. Pal; Y. X. Pan; Y. Pandit; Y. Panebratsev; T. Pawlak; B. Pawlik; H. Pei; C. Perkins; W. Peryt; A. Peterson; P. Pile; M. Planinic; J. Pluta; N. Poljak; J. Porter; A. M. Poskanzer; N. K. Pruthi; M. Przybycien; P. R. Pujahari; J. Putschke; H. Qiu; A. Quintero; S. Ramachandran; R. Raniwala; S. Raniwala; R. L. Ray; C. K. Riley; H. G. Ritter; J. B. Roberts; O. V. Rogachevskiy; J. L. Romero; J. F. Ross; A. Roy; L. Ruan; J. Rusnak; N. R. Sahoo; P. K. Sahu; I. Sakrejda; S. Salur; J. Sandweiss; E. Sangaline; A. Sarkar; J. Schambach; R. P. Scharenberg; A. M. Schmah; W. B. Schmidke; N. Schmitz; J. Seger; P. Seyboth; N. Shah; E. Shahaliev; P. V. Shanmuganathan; M. Shao; B. Sharma; W. Q. Shen; S. S. Shi; Q. Y. Shou; E. P. Sichtermann; R. N. Singaraju; M. J. Skoby; D. Smirnov; N. Smirnov; D. Solanki; P. Sorensen; U. G. deSouza; H. M. Spinka; B. Srivastava; T. D. S. Stanislaus; J. R. Stevens; R. Stock; M. Strikhanov; B. Stringfellow; A. A. P. Suaide; M. Sumbera; X. Sun; X. M. Sun; Y. Sun; Z. Sun; B. Surrow; D. N. Svirida; T. J. M. Symons; A. Szanto de Toledo; M. A. Szelezniak; J. Takahashi; A. H. Tang; Z. Tang; T. Tarnowsky; J. H. Thomas; A. R. Timmins; D. Tlusty; M. Tokarev; S. Trentalange; R. E. Tribble; P. Tribedy; B. A. Trzeciak; O. D. Tsai; J. Turnau; T. Ullrich; D. G. Underwood; G. Van Buren; G. van Nieuwenhuizen; J. A. Vanfossen, Jr.; R. Varma; G. M. S. Vasconcelos; A. N. Vasiliev; R. Vertesi; F. Videbćk; Y. P. Viyogi; S. Vokal; A. Vossen; M. Wada; F. Wang; G. Wang; H. Wang; J. S. Wang; X. L. Wang; Y. Wang; Y. Wang; G. Webb; J. C. Webb; G. D. Westfall; H. Wieman; G. Wimsatt; S. W. Wissink; R. Witt; Y. F. Wu; Z. Xiao; W. Xie; K. Xin; H. Xu; J. Xu; N. Xu; Q. H. Xu; Y. Xu; Z. Xu; W. Yan; C. Yang; Y. Yang; Y. Yang; Z. Ye; P. Yepes; L. Yi; K. Yip; I-K. Yoo; N. Yu; Y. Zawisza; H. Zbroszczyk; W. Zha; J. B. Zhang; J. L. Zhang; S. Zhang; X. P. Zhang; Y. Zhang; Z. P. Zhang; F. Zhao; J. Zhao; C. Zhong; X. Zhu; Y. H. Zhu; Y. Zoulkarneeva; M. Zyzak

2015-01-21T23:59:59.000Z

304

Sequential melting of charmonium states in an expanding Quark Gluon Plasma and $J/?$ suppression at RHIC and LHC energy collisions  

E-Print Network [OSTI]

We have developed a hydrodynamic model to study sequential melting of charmonium states in an expanding QGP medium. According to the initial fluid temperature profile, $J/\\psi$'s are randomly distributed in the transverse plane. As the fluid evolve in time, the free streaming $J/\\psi$'s are suppressed if the local fluid temperature exceed a critical temperature. PHENIX data on the centrality dependence of $J/\\psi$ suppression in Au+Au collisions at mid-rapidity are explained by sequential melting of the charmonium states, $\\chi_c$, $\\psi\\prime$ and $J/\\psi$, in the expanding medium. The critical temperatures $T_{J/\\psi} \\approx2.09T_c$ and $T_\\chi=T_{\\chi_c}=T_{\\psi\\prime} \\approx 1.1T_c$ agree with lattice motivated calculations. The feed-down fraction $F$ depend on whether the cold nuclear matter effect is included or not. It changes from $F=0.3$ with cold nuclear matter effect included to $F=0.5$ when the effect is neglected. Model fails to reproduce the PHENIX data on the centrality dependence of $J/\\psi$ suppression in Cu+Cu collisions at mid-rapidity, indicating that the mechanism of $J/\\psi$ suppression is different in Au+Au and in Cu+Cu collisions. We also use the model to predict for the centrality dependence of $J/\\psi$ suppression in Pb+Pb collisions at LHC energy, $\\sqrt{s}$=5500 GeV. In LHC energy, $J/\\psi$'s are more suppressed in mid central collisions than in Au+Au collisions at RHIC energy.

A. K. Chaudhuri

2008-07-04T23:59:59.000Z

305

Scaling of Anisotropic Flows in Intermediate Energy and Ultra-relativistic Heavy Ion Collisions  

E-Print Network [OSTI]

Anisotropic flows ($v_2$ and $v_4$) of hadrons and light nuclear clusters are studied by a partonic transport model and nucleonic transport model, respectively, in ultra-relativistic and intermediate energy heavy ion collisions. Both number-of-constituent-quark scaling of hadrons, especially for $\\phi$ meson which is composed of strange quarks, and number-of-nucleon scaling of light nuclear clusters are discussed and explored for the elliptic flow ($v_2$). The ratios of $v_4/v_2^2$ of hadrons and nuclear clusters are, respectively, calculated and they show different constant values which are independent of transverse momentum. The above phenomena can be understood, respectively, by the coalescence mechanism in quark-level or nucleon-level.

Y. G. Ma

2006-11-30T23:59:59.000Z

306

Subthreshold pion production within a transport description of central Au+Au collisions  

E-Print Network [OSTI]

Mapping out the equation of state (EOS) of nuclear matter is a long standing problem in nuclear physics. Recent emphasis is onto the density dependence of the symmetry energy, with experiments needing dedicated symmetry-energy observables. Towards the latter goal, we employ pBUU transport model to simulate pion production in heavy ion collision (HIC). We find that the net pion yield tests the momentum dependence of nuclear mean field (MF). In exploring the sensitivity of pion observables to the symmetry energy at higher than normal densities, we find that our calculations of pion ratios contradict, at some level, predictions from both IBUU and ImIQMD models. We propose to employ the pion ratio in the high-energy tail of spectra in future experiments, to distinguish between different variants of high-density symmetry energy.

Jun Hong; P. Danielewicz

2013-07-29T23:59:59.000Z

307

Nuclear scales  

SciTech Connect (OSTI)

Nuclear scales are discussed from the nuclear physics viewpoint. The conventional nuclear potential is characterized as a black box that interpolates nucleon-nucleon (NN) data, while being constrained by the best possible theoretical input. The latter consists of the longer-range parts of the NN force (e.g., OPEP, TPEP, the {pi}-{gamma} force), which can be calculated using chiral perturbation theory and gauged using modern phase-shift analyses. The shorter-range parts of the force are effectively parameterized by moments of the interaction that are independent of the details of the force model, in analogy to chiral perturbation theory. Results of GFMC calculations in light nuclei are interpreted in terms of fundamental scales, which are in good agreement with expectations from chiral effective field theories. Problems with spin-orbit-type observables are noted.

Friar, J.L.

1998-12-01T23:59:59.000Z

308

Phase-Space Description of Momentum Spectra in Relativistic Heavy-Ion Collisions  

E-Print Network [OSTI]

We consider a phase-space model for particle production in nuclear collisions. Once the multiplicities of the individual particle species are known, single-inclusive momentum spectra can be computed after making simplifying assumptions for the matrix element for multiparticle production. Comparison of the calculated spectra with data for pions and kaons from central Pb+Pb collisions at E_{Lab}=158 AGeV reveals a residual longitudinal phase-space dominance in the final state of the reaction. We account for this by modifying the isotropic, relativistic invariant phase space in a way which retains boost invariance in beam direction but suppresses large transverse momenta. Adjusting a single parameter, we obtain a reasonably good description of transverse momentum and rapidity spectra for both pions and kaons.

Deinet, W; Deinet, Werner; Rischke, Dirk H.

2006-01-01T23:59:59.000Z

309

Nuclear Proliferation Technology Trends Analysis  

SciTech Connect (OSTI)

A process is underway to develop mature, integrated methodologies to address nonproliferation issues. A variety of methodologies (both qualitative and quantitative) are being considered. All have one thing in common, a need for a consistent set of proliferation related data that can be used as a basis for application. One approach to providing a basis for predicting and evaluating future proliferation events is to understand past proliferation events, that is, the different paths that have actually been taken to acquire or attempt to acquire special nuclear material. In order to provide this information, this report describing previous material acquisition activities (obtained from open source material) has been prepared. This report describes how, based on an evaluation of historical trends in nuclear technology development, conclusions can be reached concerning: (1) The length of time it takes to acquire a technology; (2) The length of time it takes for production of special nuclear material to begin; and (3) The type of approaches taken for acquiring the technology. In addition to examining time constants, the report is intended to provide information that could be used to support the use of the different non-proliferation analysis methodologies. Accordingly, each section includes: (1) Technology description; (2) Technology origin; (3) Basic theory; (4) Important components/materials; (5) Technology development; (6) Technological difficulties involved in use; (7) Changes/improvements in technology; (8) Countries that have used/attempted to use the technology; (9) Technology Information; (10) Acquisition approaches; (11) Time constants for technology development; and (12) Required Concurrent Technologies.

Zentner, Michael D.; Coles, Garill A.; Talbert, Robert J.

2005-10-04T23:59:59.000Z

310

Exploiting Universality in Atoms with Large Scattering Lengths  

SciTech Connect (OSTI)

The focus of this research project was atoms with scattering lengths that are large compared to the range of their interactions and which therefore exhibit universal behavior at sufficiently low energies. Recent dramatic advances in cooling atoms and in manipulating their scattering lengths have made this phenomenon of practical importance for controlling ultracold atoms and molecules. This research project was aimed at developing a systematically improvable method for calculating few-body observables for atoms with large scattering lengths starting from the universal results as a first approximation. Significant progress towards this goal was made during the five years of the project.

Braaten, Eric

2012-05-31T23:59:59.000Z

311

Hydrogen atom in momentum space with a minimal length  

E-Print Network [OSTI]

A momentum representation treatment of the hydrogen atom problem with a generalized uncertainty relation,which leads to a minimal length ({\\Delta}X_{i})_{min}= \\hbar \\sqrt(3{\\beta}+{\\beta}'), is presented. We show that the distance squared operator can be factorized in the case {\\beta}'=2{\\beta}. We analytically solve the s-wave bound-state equation. The leading correction to the energy spectrum caused by the minimal length depends on \\sqrt{\\beta}. An upper bound for the minimal length is found to be about 10^{-9} fm.

Djamil Bouaziz; Nourredine Ferkous

2010-09-05T23:59:59.000Z

312

Nuclear Physics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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313

Nuclear Structure  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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314

Nuclear Forensics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert Southwest Regionat Cornell BatteriesArchives Events/NewsYouNuclearNuclear Forensics

315

Neutral Pion Production in Au+Au Collisions at sqrt sNN = 200 GeV  

SciTech Connect (OSTI)

The results of mid-rapidity (0 < y < 0.8) neutral pion spectra over an extended transverse momentum range (1 < p{sub T} < 12 GeV/c) in {radical}s{sub NN} = 200 GeV Au+Au collisions, measured by the STAR experiment, are presented. The neutral pions are reconstructed from photons measured either by the STAR Barrel Electro-Magnetic Calorimeter (BEMC) or by the Time Projection Chamber (TPC) via tracking of conversion electron-positron pairs. Our measurements are compared to previously published {pi}{sup {+-}} and {pi}{sup 0} results. The nuclear modification factors R{sub CP} and R{sub AA} of {pi}{sup 0} are also presented as a function of p{sub T}. In the most central Au+Au collisions, the binary collision scaled {pi}{sup 0} yield at high p{sub T} is suppressed by a factor of about 5 compared to the expectation from the yield of p+p collisions. Such a large suppression is in agreement with previous observations for light quark mesons and is consistent with the scenario that partons suffer considerable energy loss in the dense medium formed in central nucleus-nucleus collisions at RHIC.

STAR Collaboration; Abelev, B. I.

2009-10-23T23:59:59.000Z

316

Nuclear Nonproliferation Programs | ORNL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Nuclear Nonproliferation Programs SHARE Nuclear Nonproliferation Programs image Oak Ridge National Laboratory covers the entire spectrum of nuclear nonproliferation work, from...

317

NUCLEAR PROXIMITY FORCES  

E-Print Network [OSTI]

One might summarize of nuclear potential energy has beendegree of freedom) for the nuclear interaction between anyUniversity of California. Nuclear Proximity Forces 'I< at

Randrup, J.

2011-01-01T23:59:59.000Z

318

Global Nuclear Security  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Global Nuclear Security Both DOE and the National Nuclear Security Administration are working to reduce the risk of nuclear proliferation and provide technologies to improve...

319

amyloid fibril length: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

22 23 24 25 Next Page Last Page Topic Index 1 Intrinsic Linear Heterogeneity of Amyloid Beta Protein Fibrils Revealed by Higher Resolution Mass-per-length Determinations* Chemistry...

320

Inferring the Rate-Length Law of Protein Folding  

E-Print Network [OSTI]

We investigate the rate-length scaling law of protein folding, a key undetermined scaling law in the analytical theory of protein folding. We demonstrate that chain length is a dominant factor determining folding times, and that the unambiguous determination of the way chain length corre- lates with folding times could provide key mechanistic insight into the folding process. Four specific proposed laws (power law, exponential, and two stretched exponentials) are tested against one an- other, and it is found that the power law best explains the data. At the same time, the fit power law results in rates that are very fast, nearly unreasonably so in a biological context. We show that any of the proposed forms are viable, conclude that more data is necessary to unequivocally infer the rate-length law, and that such data could be obtained through a small number of protein folding experiments on large protein domains.

Lane, Thomas J

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Role of density dependent symmetry energy in nuclear stopping  

E-Print Network [OSTI]

Information about the nuclear matter under the extreme conditions of temperature and density and the role of symmetry energy under these conditions is still a topic of crucial importance in the present day nuclear physics research. The multifragmentation, collective flow and the nuclear stopping is among the various rare phenomenon which can be observed in heavy-ion collisions at intermediate energies. The nuclear stopping, which is sensitive towards the symmetry energy has gained a lot of interest because it provides the possibility to examine the degree of thermalization or equilibration in the matter. Aim of the present study is to pin down the nuclear stopping for the different forms of density dependent symmetry energy

Karan Singh Vinayak; Suneel Kumar

2011-07-27T23:59:59.000Z

322

Guidance Based Collision Avoidance of Coordinated Nonholonomic Autonomous Vehicles  

E-Print Network [OSTI]

Guidance Based Collision Avoidance of Coordinated Nonholonomic Autonomous Vehicles Xianbo Xiang following control, obstacle avoidance and collision free for coordinated multiple nonholonomic autonomous autonomous ve- hicles dealing with tasks could offer additional advantages, in terms of flexibility

Paris-Sud XI, Université de

323

Treatment options for tank farms long-length contaminated equipment  

SciTech Connect (OSTI)

This study evaluated a variety of treatment and disposal technologies for mixed waste (MW) meeting the following criteria: 1. Single-Shell and Double-Shell Tank System (tank farms) equipment and other debris; 2. length greater than 12 feet; and contaminated with listed MW from the tank farms. This waste stream, commonly referred to as tank farms long-length contaminated equipment (LLCE), poses a unique and costly set of challenges during all phases of the waste management lifecycle.

Josephson, W.S.

1995-10-16T23:59:59.000Z

324

Hydrogen-atom spectrum under a minimal-length hypothesis  

E-Print Network [OSTI]

The energy spectrum of the Coulomb potential with minimal length commutation relations $[X_i, P_j] = i\\hbar\\{\\delta_{ij}(1+\\beta P^2) + \\beta'P_iP_j\\}$ is determined both numerically and perturbatively for arbitrary values of $\\beta'/\\beta$ and angular momenta $\\ell$. The constraint on the minimal length scale from precision hydrogen spectroscopy data is of order of a few GeV$\

Sandor Benczik; Lay Nam Chang; Djordje Minic; Tatsu Takeuchi

2005-07-08T23:59:59.000Z

325

Nuclear Science/Nuclear Chemistry  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert Southwest Regionat Cornell BatteriesArchivesNuclear Science/Nuclear Chemistry

326

Flow and equation of state in heavy-ion collisions  

E-Print Network [OSTI]

The status of flow in heavy-ion collisions and of inference of hadronic-matter properties is reviewed.

Danielewicz, P

1999-01-01T23:59:59.000Z

327

Flow and equation of state in heavy-ion collisions  

E-Print Network [OSTI]

The status of flow in heavy-ion collisions and of inference of hadronic-matter properties is reviewed.

P. Danielewicz

1999-07-25T23:59:59.000Z

328

Flow and equation of state in heavy ion collisions (2)  

E-Print Network [OSTI]

The status of flow in heavy-ion collisions and of inference of hadronic-matter properties is reviewed.

Danielewicz, P

2001-01-01T23:59:59.000Z

329

Measurements of phi meson production in relativistic heavy-ion collisions at RHIC  

SciTech Connect (OSTI)

We present results for the measurement of {phi} meson production via its charged kaon decay channel {phi} {yields} K{sup +}K{sup -} in Au + Au collisions at {radical}s{sub NN} = 62.4, 130, and 200 GeV, and in p + p and d + Au collisions at {radical}s{sub NN} = 200 GeV from the STAR experiment at the BNL Relativistic Heavy Ion Collider (RHIC). The midrapidity (|y| < 0.5) {phi} meson transverse momentum (p{sub T}) spectra in central Au + Au collisions are found to be well described by a single exponential distribution. On the other hand, the p{sub T} spectra from p + p, d + Au and peripheral Au + Au collisions show power-law tails at intermediate and high p{sub T} and are described better by Levy distributions. The constant {phi}/K{sup -} yield ratio vs beam species, collision centrality and colliding energy is in contradiction with expectations from models having kaon coalescence as the dominant mechanism for {phi} production at RHIC. The {Omega}/{phi} yield ratio as a function of p{sub T} is consistent with a model based on the recombination of thermal s quarks up to p{sub T} {approx} 4 GeV/c, but disagrees at higher transverse momenta. The measured nuclear modification factor, R{sub dAu}, for the {phi} meson increases above unity at intermediate p{sub T}, similar to that for pions and protons, while R{sub AA} is suppressed due to the energy loss effect in central Au + Au collisions. Number of constituent quark scaling of both R{sub cp} and v{sub 2} for the {phi} meson with respect to other hadrons in Au + Au collisions at {radical}s{sub NN} = 200 GeV at intermediate p{sub T} is observed. These observations support quark coalescence as being the dominant mechanism of hadronization in the intermediate p{sub T} region at RHIC.

STAR Coll

2009-06-16T23:59:59.000Z

330

Collective flow in Au + Au collisions  

SciTech Connect (OSTI)

Based on a preliminary sample of Au + Au collisions in the EOS time projection chamber at the Bevalac, we study sideward flow as a function of bombarding energy between 0.25A GeV and 1.2A GeV. We focus on the increase in in-plane transverse momentum per nucleon with fragment mass. We also find event shapes to be close to spherical in the most central collisions, independent of bombarding energy and fragment mass up to {sup 4}He.

Ritter, H.G.; EOS Collaboration

1994-05-01T23:59:59.000Z

331

Source dimensions in ultrarelativistic heavy ion collisions  

SciTech Connect (OSTI)

Recent experiments on pion correlations, interpreted as interferometric measurements of the collision zone, are compared with models that distinguish a prehadronic phase and a hadronic phase. The models include prehadronic longitudinal expansion, conversion to hadrons in local kinetic equilibrium, and rescattering of the produced hadrons. The longitudinal radius measured in collisions of 200 GeV/u sulfur nuclei on a heavy target require the existence of a prehadronic phase which converts to the hadronic phase at densities around 0.8 GeV/fm{sup 3}. The transverse radii cannot be reproduced without introducing more complex dynamics into the transverse expansion.

Herrmann, M.; Bertsch, G.F.

1994-05-16T23:59:59.000Z

332

Jet production in ep collisions Pierre Van Mechelen  

E-Print Network [OSTI]

Jet production in ep collisions Pierre Van Mechelen University of Antwerpen Pierre electroproduction #12; Jet production in ep collisions Pierre Van Mechelen HERA, H1 and ZEUS H1 ZEUS p (920 GeV) e ± (27.6 GeV) #12; Jet production in ep collisions Pierre Van Mechelen Jet finding algorithms Clustering

333

Nuclear Incident Team | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

Incident Team | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear...

334

Pseudo-critical clusterization in nuclear multifragmentation  

E-Print Network [OSTI]

In this contribution we show that the biggest fragment charge distribution in central collisions of Xe+Sn leading to multifragmentation is an admixture of two asymptotic distributions observed for the lowest and highest bombarding energies. The evolution of the relative weights of the two components with bombarding energy is shown to be analogous to that observed as a function of time for the largest cluster produced in irreversible aggregation for a finite system. We infer that the size distribution of the largest fragment in nuclear multifragmentation is also characteristic of the time scale of the process, which is largely determined by the onset of radial expansion in this energy range.

Diego Gruyer; J. D. Frankland; R. Botet; M. Ploszajczak; E. Bonnet; A. Chbihi; P. Marini

2013-08-24T23:59:59.000Z

335

Nuclear Medicine CT Angiography  

E-Print Network [OSTI]

Nuclear Medicine CT Angiography Stress Testing Rotation The Nuclear Medicine/CT angiography. Understand the indications for exercise treadmill testing and specific nuclear cardiology tests, safe use Level 2 proficiency in performing and interpreting cardiac nuclear imaging tests. Progression

Ford, James

336

Isospin Effects in Heavy-Ion Collisions: Some Results From CHIMERA Experiments At LNS And Perspectives With Radioactive Beams  

SciTech Connect (OSTI)

CHIMERA is a 4{pi} multidetector for charged particles available at Laboratori Nazionali del Sud (INFN-LNS). A new method to measure the time scale of the emission of nuclear fragments is described, together with some applications in the field of the isospin dynamics of heavy-ion collisions. Competition between fusion-like and binary reactions near the energy threshold for nuclear multifragmentation is discussed. Opportunities are pointed out to use the detector at low and intermediate energies using the kinematical-coincidence method.

Cardella, G.; De Filippo, E.; Pagano, A.; Papa, M.; Pirrone, S.; Verde, G. [INFN, Sez di Catania, Via S. Sofia 64-95123 Catania (Italy); Amorini, F.; Cavallaro, S.; Lombardo, I.; Porto, F.; Rizzo, F.; Russotto, P. [INFN Lab. Naz. del Sud, Via S. Sofia 44-95123 Catania (Italy); Dep. of Phys. and Astr. Univ. Catania Via S. Sofia 64-95123 Catania (Italy); Anzalone, A.; Maiolino, C. [INFN Lab. Naz. del Sud, Via S. Sofia 44-95123 Catania (Italy); Arena, N.; Geraci, E.; Grassi, L.; Lo Nigro, S.; Politi, G. [INFN, Sez di Catania, Via S. Sofia 64-95123 Catania (Italy); Dep. of Phys. and Astr. Univ. Catania Via S. Sofia 64-95123 Catania (Italy); Auditore, L. [INFN and Dep. of Phys. Univ. Messina (Italy)] (and others)

2009-05-04T23:59:59.000Z

337

National Nuclear Security Administration  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

FROM: SUBJECT: USIUK Memorandum of Understanding between National Nuclear Security Administration's (NNSA) Associate Administrator for Defense Nuclear Security (AADNS)...

338

Nuclear spectroscopic studies. Progress report  

SciTech Connect (OSTI)

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.

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

1993-02-08T23:59:59.000Z

339

Free magnetized knots of parity-violating deconfined matter in heavy-ion collisions  

E-Print Network [OSTI]

We show that the local parity violation in the quark-gluon plasma supports existence of free (meta)stable knots of deconfined hot quark matter stabilized by superstrong magnetic fields. The magnetic field in the knots resembles the spheromak plasma state of the magnetic confinement approach to nuclear fusion. The size of the knot is quantized, being inversely proportional to the chiral conductivity of the quark-gluon plasma. The parity symmetry is broken inside the knot. Particles produced in the decays of the knots have unusual azimuthal distribution and specific flavor content. We argue that these knots may be created in noncentral heavy-ion collisions.

M. N. Chernodub

2010-02-07T23:59:59.000Z

340

Free magnetized knots of parity-violating deconfined matter in heavy-ion collisions  

E-Print Network [OSTI]

We show that the local parity violation in the quark-gluon plasma supports existence of free (meta)stable knots of deconfined hot quark matter stabilized by superstrong magnetic fields. The magnetic field in the knots resembles the spheromak plasma state of the magnetic confinement approach to nuclear fusion. The size of the knot is quantized, being inversely proportional to the chiral conductivity of the quark-gluon plasma. The parity symmetry is broken inside the knot. Particles produced in the decays of the knots have unusual azimuthal distribution and specific flavor content. We argue that these knots may be created in noncentral heavy-ion collisions.

Chernodub, M N

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Dynamics of $K^+$ Production in Heavy Ion Collisions close to Threshold  

E-Print Network [OSTI]

In this article the production of $K^+$ at energies close to the threshold is studied in detail. The production mechanisms, the influence of in-medium effects, cross sections, the nuclear equation of state and the dynamics of the nucleons on the kaon dynamics are discussed. A special regard will be taken on the collision of Au+Au at 1.5 GeV, a reaction that has recently been analyzed in detail by experiments performed by the KaoS and FOPI collaborations at the SIS accelerator at GSI.

Christoph Hartnack

2005-07-01T23:59:59.000Z

342

Scaling laws for near barrier Coulomb and Nuclear Breakup  

E-Print Network [OSTI]

We investigate the nuclear and the Coulomb contributions to the breakup cross sections of $^6$Li in collisions with targets in different mass ranges. Comparing cross sections for different targets at collision energies corresponding to the same $E/V_{\\mathrm{\\scriptscriptstyle B}}$, we obtain interesting scaling laws. First, we derive an approximate linear expression for the nuclear breakup cross section as a function of $A_{\\mathrm{% \\scriptscriptstyle T}}^{1/3}$. We then confirm the validity of this expression performing CDCC calculations. Scaling laws for the Coulomb breakup cross section are also investigated. In this case, our CDCC calculations indicate that this cross section has a linear dependence on the atomic number of the target. This behavior is explained by qualitative arguments. Our findings, which are consistent with previously obtained results for higher energies, are important when planning for experiments involving exotic weakly bound nuclei.

M. S. Hussein; P. R. S. Gomes; J. Lubian; D. R. Otomar; L. F. Canto

2013-09-05T23:59:59.000Z

343

Two Permanently Congruent Rods May Have Different Proper Lengths  

E-Print Network [OSTI]

We scrutinize congruence as one of the basic definitions of equality in geometry and pit it against physics of Special Relativity. We show that two non-rigid rods permanently kept congruent during their common expansion or compression may have different instantaneous proper lengths (when measured at the same time of their respective reference clocks) if they have different mass distributions over their lengths. Alternatively, their proper lengths can come out equal only when measured at different but strictly correlated moments of time of their respective clocks. The derived expression for the ratio of instantaneous proper lengths of two permanently congruent changing objects explicitly contains information about the objects mass distribution. The same is true for the ratio of readings of the two reference clocks, for which the instantaneous measurements of respective proper lengths produce the same result. In either case the characteristics usually considered as purely kinematic depend on mass distribution, which is a dynamic property. This is a spectacular demonstration of dynamic aspect of geometry already in the framework of Special Relativity.

Moses Fayngold

2008-07-06T23:59:59.000Z

344

Isotropic-nematic phase behavior of length polydisperse hard rods  

E-Print Network [OSTI]

The isotropic-nematic phase behavior of length polydisperse hard rods with arbitrary length distributions is calculated. Within a numerical treatment of the polydisperse Onsager model using the Gaussian trial function Ansatz we determine the onset of isotropic-nematic phase separation, coming from a dilute isotropic phase and a dense nematic phase. We focus on parent systems whose lengths can be described by either a Schulz or a `fat-tailed' log-normal distribution with appropriate lower and upper cutoff lengths. In both cases, very strong fractionation effects are observed for parent polydispersities larger than roughly 50 %. In these regimes, the isotropic and nematic phases are completely dominated by respectively the shortest and the longest rods in the system. Moreover, for the log-normal case, we predict triphasic isotropic-nematic-nematic equilibria to occur above a certain threshold polydispersity. By investigating the properties of the coexisting phases across the coexistence region for a particular set of cutoff lengths we explicitly show that the region of stable triphasic equilibria does not extend up to very large parent polydispersities but closes off at a consolute point located not far above the threshold polydispersity. The experimental relevance of the phenomenon is discussed.

H. H. Wensink; G. J. Vroege

2003-04-18T23:59:59.000Z

345

Feedback Mechanism for Microtubule Length Regulation by Stathmin Gradients  

E-Print Network [OSTI]

We formulate and analyze a theoretical model for the regulation of microtubule (MT) polymerization dynamics by the signaling proteins Rac1 and stathmin. In cells, the MT growth rate is inhibited by cytosolic stathmin, which, in turn, is inactivated by Rac1. Growing MTs activate Rac1 at the cell edge, which closes a positive feedback loop. We investigate both tubulin sequestering and catastrophe promotion as mechanisms for MT growth inhibition by stathmin. For a homogeneous stathmin concentration in the absence of Rac1, we find a switch-like regulation of the MT mean length by stathmin. For constitutively active Rac1 at the cell edge, stathmin is deactivated locally, which establishes a spatial gradient of active stathmin. In this gradient, we find a stationary bimodal MT length distributions for both mechanisms of MT growth inhibition by stathmin. One subpopulation of the bimodal length distribution can be identified with fast growing and long pioneering MTs in the region near the cell edge, which have been observed experimentally. The feedback loop is closed through Rac1 activation by MTs. For tubulin sequestering by stathmin, this establishes a bistable switch with two stable states: one stable state corresponds to upregulated MT mean length and bimodal MT length distributions, i.e., pioneering MTs; the other stable state corresponds to an interrupted feedback with short MTs. Stochastic effects as well as external perturbations can trigger switching events. For catastrophe promoting stathmin we do not find bistability.

Maria Zeitz; Jan Kierfeld

2014-12-09T23:59:59.000Z

346

Collision analysis for an UAV Anna Desilles  

E-Print Network [OSTI]

Collision analysis for an UAV Anna D´esilles , Hasnaa Zidani ENSTA ParisTech , Paris, 75015, France capacity of Unmanned Aerial Vehicles (UAV) is one of the key elements to open the access to airspace for UAVs. In order to replace a pilot's See and Avoid capacity such a system has to be certified "as safe

Paris-Sud XI, Université de

347

PROMPT PHOTON PRODUCTION IN POLARIZED HADRON COLLISIONS.  

SciTech Connect (OSTI)

We consider spin asymmetries for prompt photon production in collisions of longitudinally polarized hadrons. This reaction will be a key tool at the BNL-RHIC {rvec p}{rvec p} collider for determining the gluon spin density in a polarized proton. We study the effects of QCD corrections, such as all-order soft-gluon ''threshold'' resummations.

VOGELSANG,W.

2000-04-25T23:59:59.000Z

348

Collision Avoidance in Depth Space I. INTRODUCTION  

E-Print Network [OSTI]

; compute distances between the obstacles and the robot; optionally project the results in the CartesianCollision Avoidance in Depth Space I. INTRODUCTION When humans and robots share the same work space, safety is the primary issue of concern [8]. Secondary but not negligible is to prevent robot damages due

De Luca, Alessandro

349

Causal dissipative hydrodynamics for heavy ion collisions  

E-Print Network [OSTI]

We briefly discuss the recent developments in causal dissipative hydrodynamic for relativistic heavy ion collisions. Phenomenological estimate of QGP viscosity over entropy ratio from several experimental data, e.g. STAR's $\\phi$ meson data, centrality dependence of elliptic flow, universal scaling elliptic flow etc. are discussed. QGP viscosity, extracted from hydrodynamical model analysis can have very large systematic uncertainty due to uncertain initial conditions.

Chaudhuri, A K

2011-01-01T23:59:59.000Z

350

Causal dissipative hydrodynamics for heavy ion collisions  

E-Print Network [OSTI]

We briefly discuss the recent developments in causal dissipative hydrodynamic for relativistic heavy ion collisions. Phenomenological estimate of QGP viscosity over entropy ratio from several experimental data, e.g. STAR's $\\phi$ meson data, centrality dependence of elliptic flow, universal scaling elliptic flow etc. are discussed. QGP viscosity, extracted from hydrodynamical model analysis can have very large systematic uncertainty due to uncertain initial conditions.

A. K. Chaudhuri

2011-01-23T23:59:59.000Z

351

Sufficient Conditions for Collision-Resistant Hashing  

E-Print Network [OSTI]

information retrieval (PIR) protocols and homomorphic one-way commitments. Keywords. Collision-resistant hash. A homomorphic encryption is a semantically secure encryption in which the plaintexts are taken from a group (single-server, sublinear-communication) one-round PIR protocol [15]. Since PIR is implied by homomorphic

Ostrovsky, Rafail

352

High energy photon-photon collisions  

SciTech Connect (OSTI)

The collisions of high energy photons produced at a electron-positron collider provide a comprehensive laboratory for testing QCD, electroweak interactions and extensions of the standard model. The luminosity and energy of the colliding photons produced by back-scattering laser beams is expected to be comparable to that of the primary e{sup +}e{sup {minus}} collisions. In this overview, we shall focus on tests of electroweak theory in photon-photon annihilation, particularly {gamma}{gamma} {yields} W{sup +}W{sup {minus}}, {gamma}{gamma} {yields} Higgs bosons, and higher-order loop processes, such as {gamma}{gamma} {yields} {gamma}{gamma}, Z{gamma} and ZZ. Since each photon can be resolved into a W{sup +}W{sup minus} pair, high energy photon-photon collisions can also provide a remarkably background-free laboratory for studying WW collisions and annihilation. We also review high energy {gamma}{gamma} tests of quantum chromodynamics, such as the scaling of the photon structure function, t{bar t} production, mini-jet processes, and diffractive reactions.

Brodsky, S.J. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Zerwas, P.M. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

1994-07-01T23:59:59.000Z

353

Heavy Flavors in High Energy ep Collisions  

E-Print Network [OSTI]

Most recent measurements of open charm and beauty production in high energy ep collisions at HERA are reviewed. The measurements explored the different aspects of quantum chromodynamics involved in the process of heavy flavor production. The results are compared with perturbative theoretical calculations at next-to-leading order.

Meng Wang

2005-10-14T23:59:59.000Z

354

Curved and diffuse interface effects on the nuclear surface tension  

E-Print Network [OSTI]

We redefine the surface tension coefficient for a nuclear Fermi-liquid drop with a finite diffuse layer. Following Gibbs-Tolman concept, we introduce the equimolar radius R_e of sharp surface droplet at which the surface tension is applied and the radius of tension surface R_s which provides the minimum of the surface tension coefficient \\sigma. This procedure allows us to derive both the surface tension and the corresponding curvature correction (Tolman length) correctly for the curved and diffuse interface. We point out that the curvature correction depends significantly on the finite diffuse interface. This fact is missed in traditional nuclear considerations of curvature correction to the surface tension. We show that Tolman's length \\xi is negative for nuclear Fermi-liquid drop. The value of the Tolman length is only slightly sensitive to the Skyrme force parametrization and equals \\xi=-0.36 fm.

V. M. Kolomietz; S. V. Lukyanov; A. I. Sanzhur

2012-01-30T23:59:59.000Z

355

Nuclear photonics  

SciTech Connect (OSTI)

With the planned new {gamma}-beam facilities like MEGa-ray at LLNL (USA) or ELI-NP at Bucharest (Romania) with 10{sup 13}{gamma}/s and a band width of {Delta}E{gamma}/E{gamma} Almost-Equal-To 10{sup -3}, a new era of {gamma} beams with energies up to 20MeV comes into operation, compared to the present world-leading HI{gamma}S facility at Duke University (USA) with 10{sup 8}{gamma}/s and {Delta}E{gamma}/E{gamma} Almost-Equal-To 3 Dot-Operator 10{sup -2}. In the long run even a seeded quantum FEL for {gamma} beams may become possible, with much higher brilliance and spectral flux. At the same time new exciting possibilities open up for focused {gamma} beams. Here we describe a new experiment at the {gamma} beam of the ILL reactor (Grenoble, France), where we observed for the first time that the index of refraction for {gamma} beams is determined by virtual pair creation. Using a combination of refractive and reflective optics, efficient monochromators for {gamma} beams are being developed. Thus, we have to optimize the total system: the {gamma}-beam facility, the {gamma}-beam optics and {gamma} detectors. We can trade {gamma} intensity for band width, going down to {Delta}E{gamma}/E{gamma} Almost-Equal-To 10{sup -6} and address individual nuclear levels. The term 'nuclear photonics' stresses the importance of nuclear applications. We can address with {gamma}-beams individual nuclear isotopes and not just elements like with X-ray beams. Compared to X rays, {gamma} beams can penetrate much deeper into big samples like radioactive waste barrels, motors or batteries. We can perform tomography and microscopy studies by focusing down to {mu}m resolution using Nuclear Resonance Fluorescence (NRF) for detection with eV resolution and high spatial resolution at the same time. We discuss the dominating M1 and E1 excitations like the scissors mode, two-phonon quadrupole octupole excitations, pygmy dipole excitations or giant dipole excitations under the new facet of applications. We find many new applications in biomedicine, green energy, radioactive waste management or homeland security. Also more brilliant secondary beams of neutrons and positrons can be produced.

Habs, D.; Guenther, M. M.; Jentschel, M.; Thirolf, P. G. [Ludwig-Maximilians-Universitaet Muenchen, D-85748 Garching (Germany); Max Planck Institut fuer Quantenoptik, D-85748 Garching (Germany); Institut Laue-Langevin, F-38042 Grenoble (Germany); Ludwig-Maximilians-Universitaet Muenchen, D-85748 Garching (Germany)

2012-07-09T23:59:59.000Z

356

Grazing collisions of gravitational shock waves and entropy production in heavy ion collisions  

SciTech Connect (OSTI)

AdS/CFT correspondence is now widely used for the study of strongly coupled plasmas, such as those produced in ultrarelativistic heavy ion collisions at the Relativistic Heavy Ion Collider. While properties of equilibrated plasma and small deviations from equilibrium are by now reasonably well understood, the plasma's initial formation and thermal equilibration is a much more challenging issue which remains to be studied. In the dual gravity language, these problems are related to the formation of bulk black holes, and studying trapped surfaces, as we do in this work, is a way to estimate the properties (temperature and entropy) of such black holes. Extending the work by Gubser et al. for central collisions, we find numerically trapped surfaces for noncentral collisions of ultrarelativistic black holes (gravitational shock waves) with different energies. We observe that beyond a certain critical impact parameter, the trapped surface does not exist, and we argue that there are some experimental indications for a similar jump in entropy production as a function of the impact parameter in real heavy ion collisions. We also present a simple solvable example of the so-called wall-on-wall collision, for colliding objects that depend on the holographic coordinate only. Finally, we critically discuss the applicability of the AdS/CFT approach to real-world heavy ion collisions.

Lin Shu; Shuryak, Edward [Department of Physics and Astronomy, SUNY, Stony Brook, New York 11794 (United States)

2009-06-15T23:59:59.000Z

357

Pumping current of a Luttinger liquid with finite length  

E-Print Network [OSTI]

We study transport properties in a Tomonaga-Luttinger liquid in the presence of two time-dependent point like weak impurities, taking into account finite-length effects. By employing analytical methods and performing a perturbation theory, we compute the backscattering pumping current (I_bs) in different regimes which can be established in relation to the oscillatory frequency of the impurities and to the frequency related to the length and the renormalized velocity (by the electron-electron interactions) of the charge density modes. We investigate the role played by the spatial position of the impurity potentials. We also show how the previous infinite length results for I_bs are modified by the finite size of the system.

Sebastián Franchino Vińas; Pablo Pisani; Mariano Salvay

2012-03-16T23:59:59.000Z

358

Kaonic hydrogen atom and kaon-proton scattering length  

E-Print Network [OSTI]

Kaonic hydrogen is studied with various realistic potentials in an accurate numerical approach based on Sturmian functions. The kaon-proton scattering length extracted from the 1s energy shift of the kaonic hydrogen by applying the Deser-Trueman formula is severely inconsistent with the one derived by directly solving the scattering Schoedinger equation. We pay special attention to the recent measurement of the energy shift and decay width of the 1s kaonic hydrogen state by the DEAR Collaboration. After taking into account the large discrepancy between the extracted and directly-evaluated scattering lengths, we found theoretical predictions of most chiral SU(3) based models for the kaonic hydrogen decay width are consistent with the DEAR data. We warn the SIDDHARTA collaboration that it may not be reasonable to extract kaon-nucleon scattering lengths, by using the Coulomb-interaction corrected Deser-Truemab formula, from the planned measurement of kaonic hydrogen.

Y. Yan

2009-05-29T23:59:59.000Z

359

Dynamic nuclear polarization in biomolecular solid state NMR : methods and applications in peptides and membrane proteins  

E-Print Network [OSTI]

Solid state NMR can probe structure and dynamics on length scales from the atomic to the supramolecular. However, low sensitivity limits its application in macromolecules. NMR sensitivity can be improved by dynamic nuclear ...

Bajaj, Vikram Singh

2007-01-01T23:59:59.000Z

360

Hypersharp Resonant Capture of Neutrinos as a Laboratory Probe of the Planck Length  

E-Print Network [OSTI]

The 18.6 keV antineutrino line from 2-body decay of 3H in crystals can be emitted with natural width because of motional averaging by lattice vibrations despite the very long lifetime of 3H and contrary to commonly held views of linewidths in such a case. It can be resonantly captured in 3He with geometrical cross section sigma ~10-17 cm2. Using its hypersharp sensitivity DELTAE/E ~10-29 and the method of time-filtered resonance, the basic energy width ~10-24 eV expected of the 3H state can be measured to test if ultimate nuclear widths are limited by the Planck length rather than time-energy uncertainty.

R. S. Raghavan

2009-03-04T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Self-aligned submicron gate length gallium arsenide MESFET  

E-Print Network [OSTI]

-biaserl saturation currents of 396. 67 + 83. 984 IzA were obtained for the transistors. Built- in voltages of 0. 8198 6 0. 007 V and ideality factors of 1. 456 6 0. 0079 were obtained for the Schottky diodes. The effect of gate length on transcond ictance... Geometrical and physical origins for the small signal equivalent circuit of FET Developed fabrication process for submicron gate length GaAs MESFET Transistor and Schottky diode mask patterns 10 13 15 16 18 19 21 23 23 25 25 32 34 18. Process...

Huang, Hsien-Ching

2012-06-07T23:59:59.000Z

362

The ALICE muon spectrometer: trigger detectors and quarkonia detection in p-p collisions  

E-Print Network [OSTI]

This work was carried out in the context of the optimisation of the performances of the muon spectrometer of the forthcoming ALICE experiment at the Large Hadron Collider (LHC, CERN). The aim of ALICE is the study of nuclear matter at the highest energy densities ever accessed experimentally. More in detail, the focus is on the expected phase transition to a deconfined phase of matter where the degrees of freedom are those of quarks and gluons: the Quark-Gluon Plasma. The conditions for QGP formation are expected to be achieved in highly relativistic heavy ion collisions. The energy in the centre of mass of Pb-Pb collisions at the LHC will be 5.5 TeV per nucleon pair. The ALICE physics program also includes data-taking in p-p collisions at the centre-of-mass-energy of 14 TeV. The ALICE muon spectrometer has been designed for the detection of heavy quarkonia through their muon decay: both theoretical predictions and experimental data obtained at SPS and RHIC indicate that the production of these resonances sho...

Gagliardi, Martino

363

Initialization of hydrodynamics in relativistic heavy ion collisions with an energy-momentum transport model  

E-Print Network [OSTI]

A key ingredient of hydrodynamical modeling of relativistic heavy ion collisions is thermal initial conditions, an input that is the consequence of a pre-thermal dynamics which is not completely understood yet. In the paper we employ a recently developed energy-momentum transport model of the pre-thermal stage to study influence of the alternative initial states in nucleus-nucleus collisions on flow and energy density distributions of the matter at the starting time of hydrodynamics. In particular, the dependence of the results on isotropic and anisotropic initial states is analyzed. It is found that at the thermalization time the transverse flow is larger and the maximal energy density is higher for the longitudinally squeezed initial momentum distributions. The results are also sensitive to the relaxation time parameter, equation of state at the thermalization time, and transverse profile of initial energy density distribution: Gaussian approximation, Glauber Monte Carlo profiles, etc. Also, test results ensure that the numerical code based on the energy-momentum transport model is capable of providing both averaged and fluctuating initial conditions for the hydrodynamic simulations of relativistic nuclear collisions.

V. Yu. Naboka; S. V. Akkelin; Iu. A. Karpenko; Yu. M. Sinyukov

2015-01-14T23:59:59.000Z

364

Proposal for a High Energy Nuclear Database  

E-Print Network [OSTI]

We propose to develop a high-energy heavy-ion experimental database and make it accessible to the scientific community through an on-line interface. This database will be searchable and cross-indexed with relevant publications, including published detector descriptions. Since this database will be a community resource, it requires the high-energy nuclear physics community's financial and manpower support. This database should eventually contain all published data from Bevalac, AGS and SPS to RHIC and LHC energies, proton-proton to nucleus-nucleus collisions as well as other relevant systems, and all measured observables. Such a database would have tremendous scientific payoff as it makes systematic studies easier and allows simpler benchmarking of theoretical models to a broad range of old and new experiments. Furthermore, there is a growing need for compilations of high-energy nuclear data for applications including stockpile stewardship, technology development for inertial confinement fusion and target and ...

Vogt, D A B R

2005-01-01T23:59:59.000Z

365

Phase diagram for the asymmetric nuclear matter in the multifragmentation model  

E-Print Network [OSTI]

We assume that, in equilibrium, nuclear matter at reduced density and moderate finite temperature, breaks up into many fragments. A strong support to this assumption is provided by date accumulated from intermediate energy heavy ion collisions. The break-up of hot and expanded nuclear matter according to rules of equilibrium statistical mechanics is the multifragmentation model. The model gives a first order phase transition. This is studied in detail here. Phase-equilibrium lines for different degrees of asymmetry are computed.

G. Chaudhuri; S. Das Gupta

2009-08-11T23:59:59.000Z

366

Z Production as a Test of Nuclear Effects at the LHC  

E-Print Network [OSTI]

We predict the Z transverse momentum distribution from proton-proton and nuclear collisions at the LHC. After demonstrating that higher-twist nuclear effects are very small, we propose $Z^0$ production as a precision test for leading-twist pQCD in the TeV energy region. We also point out that shadowing may result in unexpected phenomenology at the LHC.

Xiaofei Zhang; George Fai

2002-05-15T23:59:59.000Z

367

Determining the density dependence of the nuclear symmetry energy using heavy-ion reactions  

E-Print Network [OSTI]

We review recent progress in the determination of the subsaturation density behavior of the nuclear symmetry energy from heavy-ion collisions as well as the theoretical progress in probing the high density behavior of the symmetry energy in heavy-ion reactions induced by high energy radioactive beams. We further discuss the implications of these results for the nuclear effective interactions and the neutron skin thickness of heavy nuclei.

Lie-Wen Chen; Che Ming Ko; Bao-An Li; Gao-Chan Yong

2007-11-12T23:59:59.000Z

368

Nuclear Forensics  

National Nuclear Security Administration (NNSA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "ofEarlyEnergyDepartmentNationalRestart of the Review ofElectronic InputNuclearNature of7379583Forensics

369

Nuclear Science  

Office of Environmental Management (EM)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) "of EnergyEnergyENERGY TAXBalanced ScorecardReactor Technology Subcommittee of NEACSummary Nuclear

370

Nuclear Nonproliferation,  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recoveryLaboratory | NationalJohnSecurityControls |Navy Nuclear Navy Posted:Sensor

371

Nuclear Astrophysics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert Southwest Regionat Cornell BatteriesArchives Events/NewsYouNuclear Astrophysics One

372

On Postnikov's Hook Length Formula for Binary Trees  

E-Print Network [OSTI]

note that Seo [7] also found combinatorial proof of the identity (1). Further studies related to Postnikov's hook length formula (1) have been carried out by Du and Liu [1], Gessel and Seo [2], Liu [4., 28 (2007), 1312-1321. [2] I. M. Gessel and S. Seo, A refinement of Cayley's formula for trees

Chen, Bill

373

ATP Hydrolysis Stimulates Large Length Fluctuations in Single Actin Filaments  

E-Print Network [OSTI]

ATP Hydrolysis Stimulates Large Length Fluctuations in Single Actin Filaments Evgeny B. Stukalin is investigated theoretically using a stochastic model that takes into account the hydrolysis of ATP filaments. It is found that the ATP hydrolysis has a strong effect on dynamic properties of single actin

374

Multi-length Scale Modeling of CVD of Diamond Films  

E-Print Network [OSTI]

) of single-- crystalline and polycrystalline diamond films in acrystalline and polycrystalline diamond filmsMulti-length Scale Modeling of CVD of Diamond Films M. Grujicic and S. G. LaiM. Grujicic and S. G-scale Modeling of CVD Deposition of Diamond Films RotatingRotating--disk Hotdisk Hot--filament CVD

Grujicic, Mica

375

Tuning a short coherence length Josephson junction through a  

E-Print Network [OSTI]

Tuning a short coherence length Josephson junction through a metal-insulator transition J. K University, Josephson Junction talk, 2001 #12;Josephson Tunnel Junctions · A Superconductor maintaining nonhysteretic behavior. J. K. Freericks, Georgetown University, Josephson Junction talk, 2001 S N

Freericks, Jim

376

Branch length distribution in TREF fractionated polyethylene Ramnath Ramachandran a  

E-Print Network [OSTI]

Branch length distribution in TREF fractionated polyethylene Ramnath Ramachandran a , Gregory Keywords: Polyethylene Branching Neutron scattering a b s t r a c t Commercial polyethylene is typically and catalyst activity. Further, processing of polyethylene after polymerization may also result in changes

Beaucage, Gregory

377

Introduction Fracture at small length scales is a concern  

E-Print Network [OSTI]

Introduction Fracture at small length scales is a concern in many advanced technologies. Micro. These constrained geometries localize cracking so that fracture may not compromise the structural integrity functions. For example, lo- calized fracture of a dielectric film adjacent to a conducting line

Suo, Zhigang

378

Long-length contaminated equipment burial containers fabrication process procedures  

SciTech Connect (OSTI)

These special process procedures cover the detailed step-by-step procedures required by the supplier who will manufacture the Long-Length Contaminated Equipment (LLCE) Burial Container design. Also included are detailed step-by-step procedures required by the disposal process for completion of the LLCE Burial Containers at Hanford.

McCormick, W.A., Fluor Daniel Hanford

1997-03-11T23:59:59.000Z

379

DATA AVAILABILITY, LANDINGS, AND LENGTH TRENDS OF CALIFORNIA'S ROCKFISH  

E-Print Network [OSTI]

the 1980- 1989 data to fork length using standard conversion factors from Echeverria and Lenarz (1984). For those species which did not have conversion factors, conversion factors from a similarly shaped species factors from Echeverria and Lenarz (1984). For the few species where conversions were not available

380

TRANSGENIC COTTON WITH IMPROVED FIBER MICRONAIRE, STRENGTH, AND LENGTH AND  

E-Print Network [OSTI]

483 TRANSGENIC COTTON WITH IMPROVED FIBER MICRONAIRE, STRENGTH, AND LENGTH AND INCREASED FIBER. Keating, N. G. Srinivas, C. Wu and A. S. Holaday Texas Tech University Lubbock, TX G. J. Jividen Cotton Incorporated Raleigh, NC Abstract We set out to use genetic engineering to make cotton crop yield and fiber

Strauss, Richard E.

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

IE 361 Module 15 The Average Run Length Concept  

E-Print Network [OSTI]

IE 361 Module 15 The Average Run Length Concept Reading: Section 3.5 of Statistical Quality Assurance Methods for Engineers Prof. Steve Vardeman and Prof. Max Morris Iowa State University Vardeman Electric set of alarm rules to a control charting scheme? The most e¤ective means known for making

Vardeman, Stephen B.

382

Nuclear Physics A 757 (2005) 127 Quarkgluon plasma and color glass condensate at  

E-Print Network [OSTI]

Nuclear Physics A 757 (2005) 1­27 Quark­gluon plasma and color glass condensate at RHIC hadronic and partonic matter produced in ultrarelativistic heavy ion collisions at RHIC. A particular focus, the so-called quark­gluon plasma (QGP). We also discuss evidence for a possible precursor state

383

Nuclear shadowing and prompt photons at relativistic hadron colliders  

E-Print Network [OSTI]

The production of prompt photons at high energies provides a direct probe of the dynamics of the strong interactions. In particular, one expect that it could be used to constrain the behavior of the nuclear gluon distribution in $pA$ and $AA$ collisions. In this letter we investigate the influence of nuclear effects in the production of prompt photons and estimate the transverse momentum dependence of the nuclear ratios $R_{pA} = {\\frac{d\\sigma (pA)}{dy d^2 p_T}} / A {\\frac{d\\sigma (pp)}{dy d^2 p_T}}$ and $R_{AA} = {\\frac{d\\sigma (AA)}{dy d^2 p_T}} / A^2 {\\frac{d\\sigma (pp)}{dy d^2 p_T}}$ at RHIC and LHC energies. We demonstrate that the study of these observables can be useful to determine the magnitude of the shadowing and antishadowing effects in the nuclear gluon distribution.

C. Brenner Mariotto; V. P. Goncalves

2008-08-26T23:59:59.000Z

384

$J/?$ suppression in Pb+Pb collisions and $p_T$ broadening  

E-Print Network [OSTI]

We have analysed the NA50 data, on the centrality dependence of $p_T$ broadening of $J/\\psi$'s, in Pb+Pb collisions, at the CERN-SPS. The data were analysed in a QCD based model, where $J/\\psi$'s are suppressed in 'nuclear' medium. Without any free parameter, the model could explain the NA50 $p_T$ broadening data. The data were also analysed in a QGP based threshold model, where $J/\\psi$ suppression is 100% above a critical density. The QGP based model could not explain the NA50 $p_T$ broadening data. We have also predicted the centrality dependence of $J/\\psi$ suppression and $p_T$ broadening at RHIC energy. Both the models, the QGP based threshold model and the QCD based nuclear absorption model, predict $p_T$ broadening very close to each other.

A. K. Chaudhuri

2003-04-10T23:59:59.000Z

385

Security and Use Control of Nuclear Explosives and Nuclear Weapons...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

4C, Security and Use Control of Nuclear Explosives and Nuclear Weapons by LtCol Karl Basham Functional areas: Nuclear Explosives, Nuclear Weapons, Security The Order establishes...

386

Association of length-slow silica with evaporites  

SciTech Connect (OSTI)

In 1971, Folk and Pittman described the common occurrence of length-slow quartz (or lutecite) with evaporitic minerals, and they suggested that lutecite might be a useful indicator for vanished evaporites. However, the subsequent discoveries of length-slow silica in carbonate turbidites and in abyssal Pacific cherts revealed that lutecite is not restricted to near-surface deposits. Moreover, Kastner found that length-slow quartz could be crystallized in slightly alkaline solutions enriched in Mg[sup 2+], Na[sup +], and SO[sub 4][sup [minus]2]. Following these studies, researchers have cited the presence of lutecite in rock samples as suggestive but not compelling evidence for an evaporitic origin, and the precise nature of this form of silica has remained somewhat enigmatic. Investigations of chert nodules from evaporitic and non-evaporitic regimes support an identification of length-slow quartz'' with the mineral moganite, a polymorph of silica that is fibrous and optically length slow. Results are based upon X-ray powder diffraction of the chert, followed by Rietveld refinement of the X-ray patterns to quantify the weight fraction of quartz and moganite in each specimen. Most non-evaporitic chert appears to contain between 5 and 15 wt. % moganite, but evaporitic cherts often contain more than 20 wt. %. Cherts that have transformed from precursor magadiite can be particularly rich in moganite; samples from Lake Magadi, Kenya and from Harney Lake, Oregon revealed about equal parts moganite and quartz. However, the observation of decreasing abundances of moganite in rocks of increasing age indicates that moganite is metastable relative to quartz.

Heaney, P.J. (Princeton Univ., Princeton, NJ (United States). Dept. of Geology); Sheppard, R.A. (Geological Survey, Denver, CO (United States). Denver Federal Center); Post, J.E. (Smithsonian Inst., Washington, DC (United States). Dept. of Mineral Sciences)

1992-01-01T23:59:59.000Z

387

Nuclear reactor engineering  

SciTech Connect (OSTI)

Chapters are presented concerning energy from nuclear fission; nuclear reactions and radiations; diffusion and slowing-down of neutrons; principles of reactor analysis; nuclear reactor kinetics and control; energy removal; non-fuel reactor materials; the reactor fuel system; radiation protection and environmental effects; nuclear reactor shielding; nuclear reactor safety; and power reactor systems.

Glasstone, S.; Sesonske, A.

1981-01-01T23:59:59.000Z

388

On transverse energy production in hadron collisions  

E-Print Network [OSTI]

The transverse energy spectrum in the unit rapidity window in p-bar p collisions at 540 GeV c.m.s energy is calculated to the next-to-leading order accuracy O(a_s^3) and compared to the experimental data by UA(2) collaboration. We show that the calculated spectrum starts matching experimental data only at relatively large transverse energy Et=60 GeV and is in essential disagreement with it both in shape and magnitude at lower transverse energies. The data are well reproduced by HIJING Monte-Carlo generator indicating the crucial importance of all-order effects in perturbation theory as well as those of hadronization in describing the transverse energy production in hadron collisions at small and intermediate transverse energies.

Andrei Leonidov

2000-05-01T23:59:59.000Z

389

The collision of two-kinks defects  

E-Print Network [OSTI]

We have investigated the head-on collision of a two-kink and a two-antikink pair that arises as a generalization of the $\\phi^4$ model. We have evolved numerically the Klein-Gordon equation with a new spectral algorithm whose accuracy and convergence were attested by the numerical tests. As a general result, the two-kink pair is annihilated radiating away most of the scalar field. It is possible the production of oscillons-like configurations after the collision that bounce and coalesce to form a small amplitude oscillon at the origin. The new feature is the formation of a sequence of quasi-stationary structures that we have identified as lump-like solutions of non-topological nature. The amount of time these structures survives depends on the fine-tuning of the impact velocity.

T. S. Mendonça; H. P. de Oliveira

2015-02-13T23:59:59.000Z

390

Reversing a heavy-ion collision  

E-Print Network [OSTI]

We introduce a novel approach to study the longitudinal hydrodynamic expansion of the quark-gluon fluid created in heavy-ion collisions. It consists of two steps: First, we apply the maximum entropy method to reconstruct the freeze-out surface from experimentally measured particle distribution. We then take the output of the reconstruction as the "initial" condition to evolve the system back in time by solving the 1+1 ideal hydrodynamic equations analytically, using the method of Khalatnikov and Landau. We find an approximate Bjorken-like plateau in the energy density vs rapidity profile at the early times, which shrinks with time as the boundary shocks propagate inward. In Bjorken frame, the fluid velocity is close to zero within the plateau, as in the Bjorken solution, but increases outside the plateau. The results carry implications for fully numerical hydrodynamic simulations as well as models of heavy-ion collisions based on gauge-gravity duality.

Mikhail Stephanov; Yi Yin

2014-04-23T23:59:59.000Z

391

Hadronic resonance production in d + Au collisions at sqrt s NN = 200 GeV at RHIC  

SciTech Connect (OSTI)

We present the first measurements of the {rho}(770){sup 0}, K*(892), {Delta}(1232){sup ++}, {Sigma}(1385), and {Lambda}(1520) resonances in d+Au collisions at {radical}s{sub NN} = 200 GeV, reconstructed via their hadronic decay channels using the STAR detector at RHIC. The masses and widths of these resonances are studied as a function of transverse momentum (p{sub T}). We observe that the resonance spectra follow a generalized scaling law with the transverse mass (m{sub T}). The of resonances in minimum bias collisions is compared to the of {pi}, K, and {bar p}. The {rho}{sup 0}/{pi}{sup -}, K*/K{sup -}, {Delta}{sup ++}/p, {Sigma}(1385)/{Lambda}, and {Lambda}(1520)/{Lambda} ratios in d + Au collisions are compared to the measurements in minimum bias p + p interactions, where we observe that both measurements are comparable. The nuclear modification factors (R{sub dAu}) of the {rho}{sup 0}, K*, and {Sigma}* scale with the number of binary collisions (N{sub bin}) for p{sub T} > 1.2 GeV/c.

STAR Coll

2008-08-22T23:59:59.000Z

392

Evaluation of the relationship between fracture conductivity, fracture fluid production, and effective fracture length  

E-Print Network [OSTI]

Low-permeability gas wells often produce less than predicted after a fracture treatment. One of the reasons for this is that fracture lengths calculated after stimulation are often less than designed lengths. While actual fracture lengths may...

Lolon, Elyezer P.

2006-04-12T23:59:59.000Z

393

Reactor & Nuclear Systems Publications | ORNL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Nuclear Science Home | Science & Discovery | Nuclear Science | Publications and Reports | Reactor and Nuclear Systems Publications SHARE Reactor and Nuclear Systems Publications...

394

Fast Collision Detection between Geometric Models  

E-Print Network [OSTI]

John Canny ~ ~\\::> f a--·J. s -\\-o ~\\;.V\\ 0 ~{_\\:.\\':> ~0~~ iL ~ dO L~C. ' \\\\f\\,1~ 11 r -.~ 0... o..t. The importance of collision detection extends to other areas like robot motion planning and it has been extensively studied in robotics and computational geometry for more than a decade [3, 4, 5, 11, 16, 18]. But

North Carolina at Chapel Hill, University of

395

Meson interferometry in relativistic heavy ion collisions  

SciTech Connect (OSTI)

This report contains discussions on the following topics: Recent HBT results form CERN experiment NA44; interferometry results from E802/E859/E866; recent results on two particle correlations from E814; source sizes from CERN data; intermittency and interferometry; Bose-Einstein correlations in 200A GeV S+Au collisions; HBT correlations at STAR; HBT interferometry with PHENIX; HBT calculations from ARC; three pion correlations; and pion correlations in proton-induced reactions.

Not Available

1993-05-01T23:59:59.000Z

396

Effects of overlapping strings in pp collisions  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

In models for hadron collisions based on string hadronization, the strings are usually treated as independent, allowing no interaction between the confined colour fields. In studies of nucleus collisions it has been suggested that strings close in space can fuse to form "colour ropes." Such ropes are expected to give more strange particles and baryons, which also has been suggested as a signal for plasma formation. Overlapping strings can also be expected in pp collisions, where usually no phase transition is expected. In particular at the high LHC energies the expected density of strings is quite high. To investigate possible effects of rope formation, we present a model in which strings are allowed to combine into higher multiplets, giving rise to increased production of baryons and strangeness, or recombine into singlet structures and vanish. Also a crude model for strings recombining into junction structures is considered, again giving rise to increased baryon production. The models are implemented in the DIPSY MC event generator, using PYTHIA8 for hadronization, and comparison to pp minimum bias data, reveals improvement in the description of identified particle spectra.

Bierlich, Christian [Lund University; Gustafson, Gösta [Lund University; Lönnblad, Leif [Lund University; Tarasov, Andrey [JLAB

2015-03-01T23:59:59.000Z

397

Elimination of influence of neutron-skin size difference of initial colliding nuclei in Pb+Pb collisions  

E-Print Network [OSTI]

Within an isospin- and momentum-dependent transport model using as an input nucleon density profiles from Hartree-Fock calculations based on a modified Skyrme-like (MSL) model, we study how to eliminate the influence of neutron-skin size difference of initial colliding nuclei in probing the nuclear symmetry energy. Within the current experimental uncertainty range of neutron-skin size of $^{208}$Pb, the Pb+Pb collisions are performed in semicentral and peripheral collisions with impact parameters of 5 and 9fm and at beam energies from 50 MeV/nucleon to 1000 MeV/nucleon, respectively. It is shown that combination of neutron and proton collective flows, i.e., neutron-proton differential elliptic flow, neutron-proton elliptic flow difference, neutron-proton differential transverse flow and neutron-proton transverse flow difference, can effectively eliminate the effects of neutron-skin size difference and thus can be as useful sensitive observables in probing nuclear matter symmetry energy in heavy-ion collisions...

Wei, Gao-Feng

2015-01-01T23:59:59.000Z

398

Top-quark production in proton-nucleus and nucleus-nucleus collisions at LHC energies and beyond  

E-Print Network [OSTI]

Single and pair top-quark production in proton-lead (p-Pb) and lead-lead (Pb-Pb) collisions at the CERN Large Hadron Collider (LHC) and future circular collider (FCC) energies, are studied with next-to-leading-order perturbative QCD calculations including nuclear parton distribution functions. At the LHC, the pair-production cross sections amount to sigma(t-tbar) = 3.4 mub in Pb-Pb at sqrt(s) = 5.5 TeV, and sigma(t-tbar) = 60 nb in p-Pb at sqrt(s) = 8.8 TeV. At the FCC energies of sqrt(s) = 39 and 63 TeV, the same cross sections are factors of 90 and 55 times larger respectively. In the leptonic final-state t-tbar --> W+b W-bbar --> b bbar l+l- nu+nu-, after typical acceptance and efficiency cuts, one expects about 90 and 300 top-quarks per nominal LHC-year and 4.7 10^4 and 10^5 per FCC-year in Pb-Pb and p-Pb collisions respectively. The total t-tbar cross sections, dominated by gluon fusion processes, are enhanced by 3--8% in nuclear compared to p-p collisions due to an overall net gluon antishadowing, altho...

d'Enterria, David; Paukkunen, Hannu

2015-01-01T23:59:59.000Z

399

Beam-energy and system-size dependence of the space-time extent of the pion emission source produced in heavy ion collisions  

E-Print Network [OSTI]

Two-pion interferometry measurements are used to extract the Gaussian radii $R_{{\\rm out}}$, $R_{{\\rm side}}$, and $R_{{\\rm long}}$, of the pion emission sources produced in Cu$+$Cu and Au$+$Au collisions at several beam collision energies $\\sqrt{s_{_{NN}}}$ at PHENIX. The extracted radii, which are compared to recent STAR and ALICE data, show characteristic scaling patterns as a function of the initial transverse size $\\bar{R}$ of the collision systems and the transverse mass $m_T$ of the emitted pion pairs, consistent with hydrodynamiclike expansion. Specific combinations of the three-dimensional radii that are sensitive to the medium expansion velocity and lifetime, and the pion emission time duration show nonmonotonic $\\sqrt{s_{_{NN}}}$ dependencies. The nonmonotonic behaviors exhibited by these quantities point to a softening of the equation of state that may coincide with the critical end point in the phase diagram for nuclear matter.

A. Adare; S. Afanasiev; C. Aidala; N. N. Ajitanand; Y. Akiba; R. Akimoto; H. Al-Bataineh; H. Al-Ta'ani; J. Alexander; M. Alfred; A. Angerami; K. Aoki; N. Apadula; L. Aphecetche; Y. Aramaki; R. Armendariz; S. H. Aronson; J. Asai; H. Asano; E. C. Aschenauer; E. T. Atomssa; R. Averbeck; T. C. Awes; B. Azmoun; V. Babintsev; M. Bai; G. Baksay; L. Baksay; A. Baldisseri; N. S. Bandara; B. Bannier; K. N. Barish; P. D. Barnes; B. Bassalleck; A. T. Basye; S. Bathe; S. Batsouli; V. Baublis; C. Baumann; S. Baumgart; A. Bazilevsky; M. Beaumier; S. Beckman; S. Belikov; R. Belmont; R. Bennett; A. Berdnikov; Y. Berdnikov; A. A. Bickley; X. Bing; D. Black; D. S. Blau; J. G. Boissevain; J. S. Bok; H. Borel; K. Boyle; M. L. Brooks; J. Bryslawskyj; H. Buesching; V. Bumazhnov; G. Bunce; S. Butsyk; C. M. Camacho; S. Campbell; P. Castera; B. S. Chang; J. -L. Charvet; C. -H. Chen; S. Chernichenko; C. Y. Chi; J. Chiba; M. Chiu; I. J. Choi; J. B. Choi; S. Choi; R. K. Choudhury; P. Christiansen; T. Chujo; P. Chung; A. Churyn; O. Chvala; V. Cianciolo; Z. Citron; C. R. Cleven; B. A. Cole; M. P. Comets; M. Connors; P. Constantin; M. Csanád; T. Csörg?; T. Dahms; S. Dairaku; I. Danchev; K. Das; A. Datta; M. S. Daugherity; G. David; M. B. Deaton; K. DeBlasio; K. Dehmelt; H. Delagrange; A. Denisov; D. d'Enterria; A. Deshpande; E. J. Desmond; K. V. Dharmawardane; O. Dietzsch; L. Ding; A. Dion; J. H. Do; M. Donadelli; O. Drapier; A. Drees; K. A. Drees; A. K. Dubey; J. M. Durham; A. Durum; D. Dutta; V. Dzhordzhadze; L. D'Orazio; S. Edwards; Y. V. Efremenko; J. Egdemir; F. Ellinghaus; W. S. Emam; T. Engelmore; A. Enokizono; H. En'yo; S. Esumi; K. O. Eyser; B. Fadem; N. Feege; D. E. Fields; M. Finger; M. Finger; \\, Jr.; F. Fleuret; S. L. Fokin; Z. Fraenkel; J. E. Frantz; A. Franz; A. D. Frawley; K. Fujiwara; Y. Fukao; T. Fusayasu; S. Gadrat; K. Gainey; C. Gal; P. Gallus; P. Garg; A. Garishvili; I. Garishvili; H. Ge; F. Giordano; A. Glenn; H. Gong; X. Gong; M. Gonin; J. Gosset; Y. Goto; R. Granier de Cassagnac; N. Grau; S. V. Greene; M. Grosse Perdekamp; Y. Gu; T. Gunji; L. Guo; H. Guragain; H. -Ĺ. Gustafsson; T. Hachiya; A. Hadj Henni; C. Haegemann; J. S. Haggerty; K. I. Hahn; H. Hamagaki; J. Hamblen; R. Han; S. Y. Han; J. Hanks; H. Harada; E. P. Hartouni; K. Haruna; S. Hasegawa; K. Hashimoto; E. Haslum; R. Hayano; X. He; M. Heffner; T. K. Hemmick; T. Hester; H. Hiejima; J. C. Hill; R. Hobbs; M. Hohlmann; R. S. Hollis; W. Holzmann; K. Homma; B. Hong; T. Horaguchi; Y. Hori; D. Hornback; T. Hoshino; J. Huang; S. Huang; T. Ichihara; R. Ichimiya; J. Ide; H. Iinuma; Y. Ikeda; K. Imai; Y. Imazu; J. Imrek; M. Inaba; Y. Inoue; A. Iordanova; D. Isenhower; L. Isenhower; M. Ishihara; T. Isobe; M. Issah; A. Isupov; D. Ivanischev; D. Ivanishchev; B. V. Jacak; M. Javani; S. J. Jeon; M. Jezghani; J. Jia; X. Jiang; J. Jin; O. Jinnouchi; B. M. Johnson; E. Joo; K. S. Joo; D. Jouan; D. S. Jumper; F. Kajihara; S. Kametani; N. Kamihara; J. Kamin; M. Kaneta; S. Kaneti; B. H. Kang; J. H. Kang; J. S. Kang; H. Kanou; J. Kapustinsky; K. Karatsu; M. Kasai; D. Kawall; M. Kawashima; A. V. Kazantsev; T. Kempel; J. A. Key; V. Khachatryan; A. Khanzadeev; K. Kihara; K. M. Kijima; J. Kikuchi; B. I. Kim; C. Kim; D. H. Kim; D. J. Kim; E. Kim; E. -J. Kim; H. -J. Kim; H. J. Kim; K. -B. Kim; M. Kim; S. H. Kim; Y. -J. Kim; Y. K. Kim; E. Kinney; K. Kiriluk; Á. Kiss; E. Kistenev; A. Kiyomichi; J. Klatsky; J. Klay; C. Klein-Boesing; D. Kleinjan; P. Kline; T. Koblesky; L. Kochenda; V. Kochetkov; M. Kofarago; Y. Komatsu; B. Komkov; M. Konno; J. Koster; D. Kotchetkov; D. Kotov; A. Kozlov; A. Král; A. Kravitz; F. Krizek; J. Kubart; G. J. Kunde; N. Kurihara; K. Kurita; M. Kurosawa; M. J. Kweon; Y. Kwon; G. S. Kyle; R. Lacey; Y. S. Lai; J. G. Lajoie; A. Lebedev; B. Lee; D. M. Lee; J. Lee; K. Lee; K. B. Lee; K. S. Lee; M. K. Lee; S. H. Lee; S. R. Lee; T. Lee; M. J. Leitch; M. A. L. Leite; M. Leitgab; E. Leitner; B. Lenzi; B. Lewis; X. Li; P. Liebing; S. H. Lim; L. A. Linden Levy; T. Liška; A. Litvinenko; H. Liu; M. X. Liu; B. Love; R. Luechtenborg; D. Lynch; C. F. Maguire; Y. I. Makdisi; M. Makek; A. Malakhov; M. D. Malik; A. Manion; V. I. Manko; E. Mannel; Y. Mao; L. Mašek; H. Masui; S. Masumoto; F. Matathias; M. McCumber; P. L. McGaughey; D. McGlinchey; C. McKinney; N. Means; A. Meles; M. Mendoza; B. Meredith; Y. Miake; T. Mibe; A. C. Mignerey; P. Mikeš; K. Miki; A. J. Miller; T. E. Miller; A. Milov; S. Mioduszewski; D. K. Mishra; M. Mishra; J. T. Mitchell; M. Mitrovski; Y. Miyachi; S. Miyasaka; S. Mizuno; A. K. Mohanty; P. Montuenga; H. J. Moon; T. Moon; Y. Morino; A. Morreale; D. P. Morrison; S. Motschwiller; T. V. Moukhanova; D. Mukhopadhyay; T. Murakami; J. Murata; A. Mwai; T. Nagae; S. Nagamiya; Y. Nagata; J. L. Nagle; M. Naglis; M. I. Nagy; I. Nakagawa; H. Nakagomi; Y. Nakamiya; K. R. Nakamura; T. Nakamura; K. Nakano; C. Nattrass; A. Nederlof; P. K. Netrakanti; J. Newby

2014-10-09T23:59:59.000Z

400

Nuclear Explosive Safety  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

This Department of Energy (DOE) Order establishes requirements to implement the nuclear explosive safety (NES) elements of DOE O 452.1E, Nuclear Explosive and Weapon Surety Program, or successor directive, for routine and planned nuclear explosive operations (NEOs).

2015-01-26T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Nuclear Explosive Safety  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

The Order establishes requirements to implement the nuclear explosive safety (NES) elements of DOE O 452.1E, Nuclear Explosive and Weapon Surety Program, for routine and planned nuclear explosive operations (NEOs).

2014-07-10T23:59:59.000Z

402

NUCLEAR STRUCTURE DATABASE  

E-Print Network [OSTI]

CALIFORNIA NUCLEAR STRUCTURE DATABASE R. B. Firestone and E.11089 NUCLEAR STRUCTURE DATABASE by R.B. Firestone and E.iii- NUCLEAR STRUCTURE DATABASE R.B Firestone and E. Browne

Firestone, R.B.

2010-01-01T23:59:59.000Z

403

Nuclear Safety (Pennsylvania)  

Broader source: Energy.gov [DOE]

The Nuclear Safety Division conducts a comprehensive nuclear power plant oversight review program of the nine reactors at the five nuclear power sites in Pennsylvania. It also monitors the...

404

E-Print Network 3.0 - arc length control Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

length of the arc. The measurement and control of the arc... and controllability of welding current. However, due to the difficulty met in measuring the arc length in...

405

E-Print Network 3.0 - activity telomere length Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

To address questions about telomere length regulation in nonhuman primates, we stud- ied... the telomere length in ... Source: Lansdorp, Peter M. - Department of Medical...

406

Measurement of inclusive jet charged-particle fragmentation functions in Pb+Pb collisions at $\\sqrt{s_{NN}} = 2.76$ TeV with the ATLAS detector  

E-Print Network [OSTI]

Measurements of charged-particle fragmentation functions of jets produced in ultra-relativistic nuclear collisions can provide insight into the modification of parton showers in the hot, dense medium created in the collisions. ATLAS has measured jets in $\\sqrt{s_{NN}} = 2.76$ TeV Pb+Pb collisions at the LHC using a data set recorded in 2011 with an integrated luminosity of 0.14 nb$^{-1}$. Jets were reconstructed using the anti-$k_{t}$ algorithm with distance parameter values $R$ = 0.2, 0.3, and 0.4. Distributions of charged-particle transverse momentum and longitudinal momentum fraction are reported for seven bins in collision centrality for $R=0.4$ jets with $p_{{T}}^{\\mathrm{jet}}> 100$ GeV. Commensurate minimum $p_{\\mathrm{T}}$ values are used for the other radii. Ratios of fragment distributions in each centrality bin to those measured in the most peripheral bin are presented. These ratios show a reduction of fragment yield in central collisions relative to peripheral collisions at intermediate $z$ values, $0.04 \\lesssim z \\lesssim 0.2$ and an enhancement in fragment yield for $z \\lesssim 0.04$. A smaller, less significant enhancement is observed at large $z$ and large $p_{\\mathrm{T}}$ in central collisions.

ATLAS Collaboration

2014-11-21T23:59:59.000Z

407

Electron Bunch Length Measurement for LCLS at SLAC  

SciTech Connect (OSTI)

At Stanford Linear Accelerator Center (SLAC) a Bunch Length Measurement system has been developed to measure the length of the electron bunch for its new Linac Coherent Light Source (LCLS). This destructive measurement uses a transverse-mounted RF deflector (TCAV) to vertically streak the electron beam and an image taken with an insertable screen and a camera. The device control software was implemented with the Experimental Physics and Industrial Control System (EPICS) toolkit. The analysis software was implemented in Matlab{trademark} using the EPICS/Channel Access Interface for Scilab{trademark} and Matlab{trademark} (labCA). This architecture allowed engineers and physicists to develop and integrate their control and analysis without duplication of effort.

Zelazny, M.; Allison, S.; Chevtsov, Sergei; Emma, P.; Kotturi, K.d.; Loos, H.; Peng, S.; Rogind, D.; Straumann, T.; /SLAC

2007-10-04T23:59:59.000Z

408

Communication: The length and time scales of water's glass transitions  

E-Print Network [OSTI]

Using a model for the equilibrium dynamics of supercooled water, I derive the average length and time scales that govern the nonequilibrium relaxation behavior of amorphous ice prepared by rapid cooling. Upon cooling, water falls out of equilibrium whereby the temperature dependence of water's relaxation time is shown to change from super-Arrhenius to Arrhenius. A consequence of this crossover is that the location of water's glass transition temperature depends logarithmically on cooling rate. Accompanying the change in temperature dependence is the emergence of a dynamical length-scale, the size of which depends on the cooling rate and varies between angstroms and 10s of nanometers. Elucidating this protocol dependence on the properties of amorphous ice clarifies a number of previous experimental observations.

Limmer, David T

2013-01-01T23:59:59.000Z

409

Nuclear Fuel Cycle & Vulnerabilities  

SciTech Connect (OSTI)

The objective of safeguards is the timely detection of diversion of significant quantities of nuclear material from peaceful nuclear activities to the manufacture of nuclear weapons or of other nuclear explosive devices or for purposes unknown, and deterrence of such diversion by the risk of early detection. The safeguards system should be designed to provide credible assurances that there has been no diversion of declared nuclear material and no undeclared nuclear material and activities.

Boyer, Brian D. [Los Alamos National Laboratory

2012-06-18T23:59:59.000Z

410

From sideward flow to nuclear compressibility  

SciTech Connect (OSTI)

The authors use the transport model (BUU) with different optical potentials, combining density and momentum dependence with strong or weak nuclear compressibility, to simulate heavy-ion collisions. Experiment by DIOGENE allows them to show that experimental sideward flow is close to their calculations using optical potential of soft momentum- and density-dependence (Potential I), as well as calculations using optical potential of stiff pure density-dependence (Potential II). On the other hand, the Plastic Ball experiment on sideward flow, mainly due to the instrumental rejection of low transverse momentum particles, allows the authors to tell the differences between Potential I and II, with calculations using Potential I being close to the experimental data. Combining the results above, they see that only potential I with soft nuclear compressibility can describe the experimental data. The uncertainty of NN cross section in the medium leads to the uncertainty in nuclear compressibility, they estimate that the nuclear compressibility K lies between 180 and 235 MeV.

Pan, Q.; Danielewicz, P.

1993-04-01T23:59:59.000Z

411

Quantum electrodynamics in a laser and the electron laser collision  

E-Print Network [OSTI]

Quantum electrodynamics in a laser is formulated, in which the electron-laser interaction is exactly considered, while the interaction of an electron and a single photon is considered by perturbation. The formulation is applied to the electron-laser collisions. The effect of coherence between photons in the laser is therefore fully considered in these collisions. The possibility of $\\gamma-$ray laser generation by use of this kind of collision is discussed.

Qi-Ren Zhang

2014-08-08T23:59:59.000Z

412

Nuclear Safeguards | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure...

413

Nuclear Forensics | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure...

414

ATP hydrolysis stimulates large length fluctuations in single actin filaments  

E-Print Network [OSTI]

Polymerization dynamics of single actin filaments is investigated theoretically using a stochastic model that takes into account the hydrolysis of ATP-actin subunits, the geometry of actin filament tips, the lateral interactions between the monomers as well as the processes at both ends of the polymer. Exact analytical expressions are obtained for a mean growth velocity and for dispersion in length fluctuations. It is found that the ATP hydrolysis has a strong effect on dynamic properties of single actin filaments. At high concentrations of free actin monomers the mean size of unhydrolyzed ATP-cap is very large, and the dynamics is governed by association/dissociation of ATP-actin subunits. However, at low concentrations the size of the cap becomes finite, and the dissociation of ADP-actin subunits makes a significant contribution to overall dynamics. Actin filament length fluctuations reach the maximum at the boundary between two dynamic regimes, and this boundary is always larger than the critical concentration. Random and vectorial mechanisms of hydrolysis are compared, and it is found that they predict qualitatively similar dynamic properties. The possibility of attachment and detachment of oligomers is also discussed. Our theoretical approach is successfully applied to analyze the latest experiments on the growth and length fluctuations of individual actin filaments.

Evgeny B. Stukalin; Anatoly B. Kolomeisky

2005-07-27T23:59:59.000Z

415

Nuclear Power Overview  

Broader source: Energy.gov (indexed) [DOE]

San Onofre Nuclear Generating Station San Onofre Nuclear Generating Station Bob Ashe-Everest Southern California Edison 10 Incoming New Fuel Inspecting New Fuel SONGS Unit 1 Fuel...

416

Nuclear weapons modernizations  

SciTech Connect (OSTI)

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.

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

2014-05-09T23:59:59.000Z

417

Nuclear Energy Advisory Committee  

Broader source: Energy.gov [DOE]

The Nuclear Energy Advisory Committee (NEAC), formerly the Nuclear Energy Research Advisory Committee (NERAC), was established on October 1, 1998, to provide independent advice to the Office of...

418

National Nuclear Security Administration  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the safety, security and effectiveness of the nuclear deterrent without underground nuclear testing, consistent with the principles of the Stockpile Management Program...

419

Nuclear Waste Reduction  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Nuclear Waste Reduction Pyroprocessing is a promising technology for recycling used nuclear fuel and improving the associated waste management options. The process...

420

Assessment of Nuclear Resonance Fluorescence for Spent Nuclear Fuel Assay  

E-Print Network [OSTI]

Security of the National Nuclear Security Administration, USof Energys National Nuclear Security Administration (NNSA)

Quiter, Brian

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

www.physicstoday.org November 2012 Physics Today 59 Nuclear energy can provide great  

E-Print Network [OSTI]

www.physicstoday.org November 2012 Physics Today 59 Nuclear energy can provide great The Nuclear on keeping costs and book length in check. For example, most of the graphics use gray- scale, with only a few pages in the cen- ter providing color plates. In addition, in many places additional graphics could have

422

Inequalities for low-energy symmetric nuclear matter  

E-Print Network [OSTI]

Using effective field theory we prove inequalities for the correlations of two-nucleon operators in low-energy symmetric nuclear matter. For physical values of operator coefficients in the effective Lagrangian, the S = 1, I = 0 channel correlations must have the lowest energy and longest correlation length in the two-nucleon sector. This result is valid at nonzero density and temperature.

Dean Lee

2004-07-24T23:59:59.000Z

423

Measurement of $?$(1S+2S+3S) production in $p$$+$$p$ and Au$+$Au collisions at $\\sqrt{s_{_{NN}}}=200$ GeV  

E-Print Network [OSTI]

Measurements of bottomonium production in heavy ion and $p$$+$$p$ collisions at the Relativistic Heavy Ion Collider (RHIC) are presented. The inclusive yield of the three $\\Upsilon$ states, $\\Upsilon(1S+2S+3S)$, was measured in the PHENIX experiment via electron-positron decay pairs at midrapidity for Au$+$Au and $p$$+$$p$ collisions at $\\sqrt{s_{_{NN}}}=200$ GeV. The $\\Upsilon(1S+2S+3S)\\rightarrow e^+e^-$ differential cross section at midrapidity was found to be $B_{\\rm ee} d\\sigma/dy =$ 108 $\\pm$ 38 (stat) $\\pm$ 15(syst) $\\pm$ 11 (luminosity) pb in $p$$+$$p$ collisions. The nuclear modification factor in the 30\\% most central Au$+$Au collisions indicates a suppression of the total $\\Upsilon$ state yield relative to the extrapolation from $p$$+$$p$ collision data. The suppression is consistent with measurements made by STAR at RHIC and at higher energies by the CMS experiment at the Large Hadron Collider.

A. Adare; S. Afanasiev; C. Aidala; N. N. Ajitanand; Y. Akiba; R. Akimoto; H. Al-Bataineh; H. Al-Ta'ani; J. Alexander; A. Angerami; K. Aoki; N. Apadula; L. Aphecetche; Y. Aramaki; J. Asai; H. Asano; E. C. Aschenauer; E. T. Atomssa; R. Averbeck; T. C. Awes; B. Azmoun; V. Babintsev; M. Bai; G. Baksay; L. Baksay; A. Baldisseri; B. Bannier; K. N. Barish; P. D. Barnes; B. Bassalleck; A. T. Basye; S. Bathe; S. Batsouli; V. Baublis; C. Baumann; S. Baumgart; A. Bazilevsky; S. Belikov; R. Belmont; R. Bennett; A. Berdnikov; Y. Berdnikov; A. A. Bickley; X. Bing; D. S. Blau; J. G. Boissevain; J. S. Bok; H. Borel; K. Boyle; M. L. Brooks; H. Buesching; V. Bumazhnov; G. Bunce; S. Butsyk; C. M. Camacho; S. Campbell; P. Castera; B. S. Chang; W. C. Chang; J. -L. Charvet; C. -H. Chen; S. Chernichenko; C. Y. Chi; M. Chiu; I. J. Choi; J. B. Choi; S. Choi; R. K. Choudhury; P. Christiansen; T. Chujo; P. Chung; A. Churyn; O. Chvala; V. Cianciolo; Z. Citron; B. A. Cole; M. Connors; P. Constantin; M. Csanád; T. Csörg?; T. Dahms; S. Dairaku; K. Das; A. Datta; M. S. Daugherity; G. David; A. Denisov; D. d'Enterria; A. Deshpande; E. J. Desmond; K. V. Dharmawardane; O. Dietzsch; L. Ding; A. Dion; M. Donadelli; O. Drapier; A. Drees; K. A. Drees; A. K. Dubey; J. M. Durham; A. Durum; D. Dutta; V. Dzhordzhadze; L. D'Orazio; S. Edwards; Y. V. Efremenko; F. Ellinghaus; T. Engelmore; A. Enokizono; H. En'yo; S. Esumi; K. O. Eyser; B. Fadem; D. E. Fields; M. Finger; M. Finger; \\, Jr.; F. Fleuret; S. L. Fokin; Z. Fraenkel; J. E. Frantz; A. Franz; A. D. Frawley; K. Fujiwara; Y. Fukao; T. Fusayasu; K. Gainey; C. Gal; A. Garishvili; I. Garishvili; A. Glenn; H. Gong; X. Gong; M. Gonin; J. Gosset; Y. Goto; R. Granier de Cassagnac; N. Grau; S. V. Greene; M. Grosse Perdekamp; T. Gunji; L. Guo; H. -Ĺ. Gustafsson; T. Hachiya; A. Hadj Henni; J. S. Haggerty; K. I. Hahn; H. Hamagaki; R. Han; J. Hanks; E. P. Hartouni; K. Haruna; K. Hashimoto; E. Haslum; R. Hayano; X. He; M. Heffner; T. K. Hemmick; T. Hester; J. C. Hill; M. Hohlmann; R. S. Hollis; W. Holzmann; K. Homma; B. Hong; T. Horaguchi; Y. Hori; D. Hornback; S. Huang; T. Ichihara; R. Ichimiya; H. Iinuma; Y. Ikeda; K. Imai; J. Imrek; M. Inaba; A. Iordanova; D. Isenhower; M. Ishihara; T. Isobe; M. Issah; A. Isupov; D. Ivanischev; D. Ivanishchev; B. V. Jacak; M. Javani; J. Jia; X. Jiang; J. Jin; B. M. Johnson; K. S. Joo; D. Jouan; D. S. Jumper; F. Kajihara; S. Kametani; N. Kamihara; J. Kamin; S. Kaneti; B. H. Kang; J. H. Kang; J. S. Kang; J. Kapustinsky; K. Karatsu; M. Kasai; D. Kawall; A. V. Kazantsev; T. Kempel; A. Khanzadeev; K. M. Kijima; J. Kikuchi; B. I. Kim; C. Kim; D. H. Kim; D. J. Kim; E. Kim; E. -J. Kim; H. J. Kim; K. -B. Kim; S. H. Kim; Y. -J. Kim; Y. K. Kim; E. Kinney; K. Kiriluk; Á. Kiss; E. Kistenev; J. Klatsky; J. Klay; C. Klein-Boesing; D. Kleinjan; P. Kline; L. Kochenda; Y. Komatsu; B. Komkov; M. Konno; J. Koster; D. Kotchetkov; D. Kotov; A. Kozlov; A. Král; A. Kravitz; F. Krizek; G. J. Kunde; K. Kurita; M. Kurosawa; M. J. Kweon; Y. Kwon; G. S. Kyle; R. Lacey; Y. S. Lai; J. G. Lajoie; D. Layton; A. Lebedev; B. Lee; D. M. Lee; J. Lee; K. B. Lee; K. S. Lee; S. H. Lee; S. R. Lee; T. Lee; M. J. Leitch; M. A. L. Leite; M. Leitgab; B. Lenzi; B. Lewis; X. Li; P. Liebing; S. H. Lim; L. A. Linden Levy; T. Liška; A. Litvinenko; H. Liu; M. X. Liu; B. Love; D. Lynch; C. F. Maguire; Y. I. Makdisi; M. Makek; A. Malakhov; M. D. Malik; A. Manion; V. I. Manko; E. Mannel; Y. Mao; L. Mašek; H. Masui; S. Masumoto; F. Matathias; M. McCumber; P. L. McGaughey; D. McGlinchey; C. McKinney; N. Means; M. Mendoza; B. Meredith; Y. Miake; T. Mibe; A. C. Mignerey; P. Mikeš; K. Miki; A. Milov; D. K. Mishra; M. Mishra; J. T. Mitchell; Y. Miyachi; S. Miyasaka; A. K. Mohanty; H. J. Moon; Y. Morino; A. Morreale; D. P. Morrison; S. Motschwiller; T. V. Moukhanova; D. Mukhopadhyay; T. Murakami; J. Murata; T. Nagae; S. Nagamiya; J. L. Nagle; M. Naglis; M. I. Nagy; I. Nakagawa; Y. Nakamiya; K. R. Nakamura; T. Nakamura; K. Nakano; C. Nattrass; A. Nederlof; J. Newby; M. Nguyen; M. Nihashi; T. Niida; R. Nouicer; N. Novitzky; A. S. Nyanin; E. O'Brien; S. X. Oda; C. A. Ogilvie; M. Oka; K. Okada; Y. Onuki; A. Oskarsson; M. Ouchida; K. Ozawa; R. Pak; A. P. T. Palounek; V. Pantuev; V. Papavassiliou; B. H. Park; I. H. Park; J. Park; S. K. Park; W. J. Park; S. F. Pate; L. Patel; H. Pei; J. -C. Peng; H. Pereira; V. Peresedov; D. Yu. Peressounko; R. Petti; C. Pinkenburg; R. P. Pisani; M. Proissl; M. L. Purschke; A. K. Purwar; H. Qu; J. Rak; A. Rakotozafindrabe; I. Ravinovich; K. F. Read; S. Rembeczki; K. Reygers; D. Reynolds; V. Riabov; Y. Riabov; E. Richardson; N. Riveli; D. Roach; G. Roche; S. D. Rolnick; M. Rosati; S. S. E. Rosendahl; P. Rosnet; P. Rukoyatkin; P. Ruži?ka; V. L. Rykov; B. Sahlmueller; N. Saito; T. Sakaguchi; S. Sakai; K. Sakashita; V. Samsonov; M. Sano; M. Sarsour; T. Sato; S. Sawada; K. Sedgwick; J. Seele

2015-04-01T23:59:59.000Z

424

Pion, kaon, proton and anti-proton transverse momentum distributions from p+p and d+Au collisions at sqrt(sNN) = 200 GeV  

SciTech Connect (OSTI)

Identified mid-rapidity particle spectra of {pi}{sup {+-}}, K{sup {+-}}, and p({bar p}) from 200 GeV p+p and d+Au collisions are reported. A time-of-flight detector based on multi-gap resistive plate chamber technology is used for particle identification. The particle-species dependence of the Cronin effect is observed to be significantly smaller than that at lower energies. The ratio of the nuclear modification factor (R{sub dAu}) between (p+ {bar p}) and charged hadrons (h) in the transverse momentum range 1.2 < p{sub T} < 3.0 GeV/c is measured to be 1.19 {+-} 0.05(stat) {+-} 0.03(syst) in minimum-bias collisions and shows little centrality dependence. The yield ratio of (p + {bar p})/h in minimum-bias d+Au collisions is found to be a factor of 2 lower than that in Au+Au collisions, indicating that the Cronin effect alone is not enough to account for the relative baryon enhancement observed in heavy ion collisions at RHIC.

Adams, J.; Adler, C.; Aggarwal, M.M.; Ahammed, Z.; Amonett, J.; Anderson, B.D.; Anderson, M; Arkhipkin, D.; Averichev, G.S.; Badyal, S.K.; Balewski, J.; Barannikova, O.; Barnby, L.S.; Baudot, J.; Bekele, S.; Belaga, V.V.; Bellwied, R.; Berger, J.; Bezverkhny, B.I.; Bhardwaj, S.; Bhaskar, P.; Bhati, A.K.; Bichsel, H.; Billmeier, A.; Bland, L.C.; Blyth, C.O.; Bonner, B.E.; Botje, M.; Boucham, A.; Brandin, A.; Bravar, A.; Cadman, R.V.; Cai, X.Z.; Caines, H.; Calderon de la Barca Sanchez, M.; Carroll, J.; Castillo, J.; Castro, M.; Cebra, D.; Chaloupka, P.; Chattopadhyay, S.; Chen, H.F.; Chen, Y.; Chernenko, S.P.; Cherney, M.; Chikanian, A.; Choi, B.; Christie, W.; Coffin, J.P.; Cormier, T.M.; Cramer, J.G.; Crawford, H.J.; Das, D.; Das, S.; Derevschikov, A.A.; Didenko, L.; Dietel, T.; Dong, X.; Draper, J.E.; Du, F.; Dubey, A.K.; Dunin, V.B.; Dunlop, J.C.; Dutta Majumdar, M.R.; Eckardt, V.; Efimov, L.G.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Fachini, P.; Faine, V.; Faivre, J.; Fatemi, R.; Filimonov, K.; Filip, P.; Finch, E.; Fisyak, Y.; Flierl, D.; Foley, K.J.; Fu, J.; Gagliardi, C.A.; Ganti, M.S.; Gutierrez, T.D.; Gagunashvili, N.; Gans, J.; Gaudichet, L.; Germain, M.; Geurts, F.; Ghazikhanian, V.; Ghosh, P.; Gonzalez, J.E.; Grachov, O.; Grigoriev, V.; Cronstal, S.; Grosnick, D.; Guedon, M.; Guertin, S.M.; Gupta, A.; Gushin, E.; Hallman, T.J.; Hardtke, D.; Harris, J.W.; Heinz, M.; Henry, T.W.; Heppelmann, S.; Herston, T.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffmann, G.W.; Horsley, M.; Huang, H.Z.; Huang, S.L.; Humanic, T.J.; Igo, G.; Ishihara, A.; Jacobs, P.; Jacobs, W.W.; Janik, M.; Johnson, I.; Jones, P.G.; Judd, E.G.; Kabana, S.; Kaneta, M.; Kaplan, M.; Keane, D.; Kiryluk, J.; Kisiel, A.; Klay, J.; Klein, S.R.; Klyachko, A.; Koetke, D.D.; Kollegger, T.; Konstantinov, A.S.; Kopytine, S.M.; Kotchenda, L.; Kovalenko, A.D.; Kramer, M.; Kravtsov, P.; Krueger, K.; Kuhn, C.; Kulikov, A.I.; Kumar, A.; et al.

2003-09-16T23:59:59.000Z

425

The Joys of Nuclear Engineering  

SciTech Connect (OSTI)

Nuclear fuels researcher Jon Carmack talks about the satisfactions of a career in nuclear engineering.

Jon Carmack

2009-10-02T23:59:59.000Z

426

The Joys of Nuclear Engineering  

ScienceCinema (OSTI)

Nuclear fuels researcher Jon Carmack talks about the satisfactions of a career in nuclear engineering.

Jon Carmack

2010-01-08T23:59:59.000Z

427

Born-Oppenheimer approximation for mass scaling of cold-collision properties  

SciTech Connect (OSTI)

Asymptotic levels of the A {sup 1}{sigma}{sub u}{sup +} state of the two isotopomers {sup 39}K{sub 2} and {sup 39}K{sup 41}K up to the dissociation limit are investigated with a Doppler-free high resolution laser-spectroscopic experiment in a molecular beam. The observed level structure can be reproduced correctly only if a mass dependent correction term is introduced for the interaction potential. The applied relative correction in the depth of the potential is 10{sup -6}, which is in the order of magnitude expected for corrections of the Born-Oppenheimer approximation. A similar change in ground state potentials might lead to significant changes of mass-scaled properties describing cold collisions like the s-wave scattering length.

Falke, Stephan; Tiemann, Eberhard; Lisdat, Christian [Institut fuer Quantenoptik, Leibniz Universitaet Hannover, Welfengarten 1, 30167 Hannover (Germany)

2007-07-15T23:59:59.000Z

428

Constraining the nuclear matter equation of state around twice saturation density  

E-Print Network [OSTI]

Using FOPI data on elliptic flow in Au+Au collisions between 0.4 and 1.5A GeV we extract constraints for the equation of state (EOS) of compressed symmetric nuclear matter using the transport code IQMD by introducing an observable describing the evolution of the size of the elliptic flow as a function of rapidity. This observable is sensitive to the nuclear EOS and a robust tool to constrain the compressibility of nuclear matter up to 2 $\\rho_0$.

Fčvre, A Le; Reisdorf, W; Aichelin, J; Hartnack, Ch

2015-01-01T23:59:59.000Z

429

E-Print Network 3.0 - atomic collision experiments Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

experiments ... Source: Experimental High Energy Physics Collection: Plasma Physics and Fusion ; Physics 74 Ultra-cold Atom CollisionsUltra-cold Atom Collisions and Quantum...

430

E-Print Network 3.0 - antiproton-nucleus collisions simulation...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Why Model Collisions? Accurate simulation of collisions are needed in many areas. Video Games... Physically Based Simulators Robotics Movie Special Effects Ben Galluzzo, Ted...

431

Advanced nuclear fuel  

ScienceCinema (OSTI)

Kurt Terrani uses his expertise in materials science to develop safer fuel for nuclear power plants.

Terrani, Kurt

2014-07-15T23:59:59.000Z

432

Advanced nuclear fuel  

SciTech Connect (OSTI)

Kurt Terrani uses his expertise in materials science to develop safer fuel for nuclear power plants.

Terrani, Kurt

2014-07-14T23:59:59.000Z

433

Focus Article Nuclear winter  

E-Print Network [OSTI]

the climatic effects of nuclear war. Smoke from the fires started by nuclear weapons, especially the black in recorded human history. Although the number of nuclear weapons in the world has fallen from 70,000 at its and Russia could still produce nuclear winter. This theory cannot be tested in the real world. However

Robock, Alan

434

INSTRUCTIONS FOR SUBMITTING NUCLEAR  

E-Print Network [OSTI]

. Decommissioning 13 I. Performance 13 J. Nuclear Fuel 14 K. Nuclear Insurance 14 L. Relicensing or Plant RetirementCALIFORNIA ENERGY COMMISSION INSTRUCTIONS FOR SUBMITTING NUCLEAR POWER PLANT-RELATED DATA of Submitted Data 3 NUCLEAR POWER PLANT DATA REQUESTS 6 A. Environmental Impacts 6 B. Spent Fuel Generation 8 C

435

Nuclear Science & Engineering  

E-Print Network [OSTI]

. 1 Nuclear Science & Engineering Nuclear Energy Present and Future Ian H. Hutchinson Head, Department of Nuclear Science and Engineering CoPrincipal, Alcator Tokamak Project, Plasma Science and Fusion Science & Engineering Nuclear Power Plants Worldwide · US: 103 plants in operation, none under

436

Technology development for gene discovery and full-length sequencing  

SciTech Connect (OSTI)

In previous years, with support from the U.S. Department of Energy, we developed methods for construction of normalized and subtracted cDNA libraries, and constructed hundreds of high-quality libraries for production of Expressed Sequence Tags (ESTs). Our clones were made widely available to the scientific community through the IMAGE Consortium, and millions of ESTs were produced from our libraries either by collaborators or by our own sequencing laboratory at the University of Iowa. During this grant period, we focused on (1) the development of a method for preferential cloning of tissue-specific and/or rare transcripts, (2) its utilization to expedite EST-based gene discovery for the NIH Mouse Brain Molecular Anatomy Project, (3) further development and optimization of a method for construction of full-length-enriched cDNA libraries, and (4) modification of a plasmid vector to maximize efficiency of full-length cDNA sequencing by the transposon-mediated approach. It is noteworthy that the technology developed for preferential cloning of rare mRNAs enabled identification of over 2,000 mouse transcripts differentially expressed in the hippocampus. In addition, the method that we optimized for construction of full-length-enriched cDNA libraries was successfully utilized for the production of approximately fifty libraries from the developing mouse nervous system, from which over 2,500 full-ORF-containing cDNAs have been identified and accurately sequenced in their entirety either by our group or by the NIH-Mammalian Gene Collection Program Sequencing Team.

Marcelo Bento Soares

2004-07-19T23:59:59.000Z

437

Non abelian hydrodynamics and heavy ion collisions  

SciTech Connect (OSTI)

The goal of the relativistic heavy ion collisions (RHIC) program is to create a state of matter where color degrees of freedom are deconfined. The dynamics of matter in this state, in spite of the complexities of quantum chromodynamics, is largely determined by the conservation laws of energy momentum and color currents. Therefore it is possible to describe its main features in hydrodynamic terms, the very short color neutralization time notwithstanding. In this lecture we shall give a simple derivation of the hydrodynamics of a color charged fluid, by generalizing the usual derivation of hydrodynamics from kinetic theory to the non abelian case.

Calzetta, E. [Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and IFIBA, CONICET, Ciudad Universitaria, Buenos Aires 1428 (Argentina)

2014-01-14T23:59:59.000Z

438

The K+ K+ scattering length from Lattice QCD  

SciTech Connect (OSTI)

The K+K+ scattering length is calculated in fully-dynamical lattice QCD with domain-wall valence quarks on the MILC asqtad-improved gauge configurations with fourth-rooted staggered sea quarks. Three-flavor mixed-action chiral perturbation theory at next-to-leading order, which includes the leading effects of the finite lattice spacing, is used to extrapolate the results of the lattice calculation to the physical value of mK + /fK + . We find mK^+ aK^+ K^+ = â~0.352 ± 0.016, where the statistical and systematic errors have been combined in quadrature.

Silas Beane; Thomas Luu; Konstantinos Orginos; Assumpta Parreno; Martin Savage; Aaron Torok; Andre Walker-Loud

2007-09-11T23:59:59.000Z

439

Varying properties along lengths of temperature limited heaters  

DOE Patents [OSTI]

A system for heating a subsurface formation is described. The system includes an elongated heater in an opening in the formation. The elongated heater includes two or more portions along the length of the heater that have different power outputs. At least one portion of the elongated heater includes at least one temperature limited portion with at least one selected temperature at which the portion provides a reduced heat output. The heater is configured to provide heat to the formation with the different power outputs. The heater is configured so that the heater heats one or more portions of the formation at one or more selected heating rates.

Vinegar, Harold J. (Bellaire, TX); Xie, Xueying (Houston, TX); Miller, David Scott (Katy, TX); Ginestra, Jean Charles (Richmond, TX)

2011-07-26T23:59:59.000Z

440

Generalized holographic dark energy model described at the Hubble length  

E-Print Network [OSTI]

We generalize the holographic dark energy model described in Hubble length IR cutoff by assuming a slowly time varying function for holographic parameter $c^2$. We calculate the evolution of EoS parameter and the deceleration parameter as well as the evolution of dark energy density in this generalized model. We show that the phantom line is crossed from quintessence regime to phantom regime which is in agreement with observation. The evolution of deceleration parameter indicates the transition from decelerated to accelerated expansion. Eventually, we show that the GHDE with HIR cutoff can interpret the pressureless dark matter era at the early time and dark energy dominated phase later.

M. Malekjani

2012-09-25T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
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441

Dynamic optical properties in graphene: Length versus velocity gauge  

SciTech Connect (OSTI)

The dynamic optical properties of graphene are theoretically investigated in both length gauge and velocity gauge in the presence of ultrafast optical radiation field. The two gauges present different results of dynamic photo-induced carriers and optical conductance due to distinct dependencies on electric field and non-resonant optical absorption, while the two gauges give identical results in the steady state time. It shows that the choice of gauge affects evidently the dynamic optical properties of graphene. The velocity gauge represents an outcome of a real physical experiment.

Dong, H. M.; Han, K., E-mail: han6409@263.net [Department of Physics, China University of Mining and Technology, Xuzhou 221116 (China); Xu, W. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Department of Physics, Yunnan University, Kunming 650091 (China)

2014-02-14T23:59:59.000Z

442

Dynamics and length distribution of microtubules under force and confinement  

E-Print Network [OSTI]

We investigate the microtubule polymerization dynamics with catastrophe and rescue events for three different confinement scenarios, which mimic typical cellular environments: (i) The microtubule is confined by rigid and fixed walls, (ii) it grows under constant force, and (iii) it grows against an elastic obstacle with a linearly increasing force. We use realistic catastrophe models and analyze the microtubule dynamics, the resulting microtubule length distributions, and force generation by stochastic and mean field calculations; in addition, we perform stochastic simulations. We also investigate the force dynamics if growth parameters are perturbed in dilution experiments. Finally, we show the robustness of our results against changes of catastrophe models and load distribution factors.

Björn Zelinski; Nina Müller; Jan Kierfeld

2012-12-14T23:59:59.000Z

443

Optical Scattering Lengths in Large Liquid-Scintillator Neutrino Detectors  

E-Print Network [OSTI]

For liquid-scintillator neutrino detectors of kiloton scale, the transparency of the organic solvent is of central importance. The present paper reports on laboratory measurements of the optical scattering lengths of the organic solvents PXE, LAB, and Dodecane which are under discussion for next-generation experiments like SNO+, Hanohano, or LENA. Results comprise the wavelength range from 415 to 440nm. The contributions from Rayleigh and Mie scattering as well as from absorption/re-emission processes are discussed. Based on the present results, LAB seems to be the preferred solvent for a large-volume detector.

Michael Wurm; Franz von Feilitzsch; Marianne Goeger-Neff; Martin Hofmann; Tobias Lachenmaier; Timo Lewke; Teresa Marrodan Undagoitita; Quirin Meindl; Randoplh Moellenberg; Lothar Oberauer; Walter Potzel; Marc Tippmann; Sebastian Todor; Christoph Traunsteiner; Juergen Winter

2010-04-06T23:59:59.000Z

444

Static Length Scales of N=6 Chern-Simons Plasma  

E-Print Network [OSTI]

Using gravity description, we compute various static length scales of N=6 Chern Simons plasma in a strongly coupled regime. For this, we consider the CP3 compactification of the type IIA supergravity down to four dimensions, and identify all the low-lying bosonic modes up to masses corresponding to the operator dimension 3 together with all the remaining CP3 invariant modes. We find the true mass gap, the Debye screening mass and the corresponding dual operators to be probed in the field theory side.

Dongsu Bak; Kazem Bitaghsir Fadafan; Hyunsoo Min

2010-04-19T23:59:59.000Z

445

Studying Parton Energy Loss in Heavy-Ion Collisions via Direct-Photon and Charged-Particle Azimuthal Correlations  

E-Print Network [OSTI]

Charged-particle spectra associated with direct photon ($\\gamma_{dir} $) and $\\pi^0$ are measured in $p$+$p$ and Au+Au collisions at center-of-mass energy $\\sqrt{s_{_{NN}}}=200$ GeV with the STAR detector at RHIC. A hower-shape analysis is used to partially discriminate between $\\gamma_{dir}$ and $\\pi^0$. Assuming no associated charged particles in the $\\gamma_{dir}$ direction (near side) and small contribution from fragmentation photons ($\\gamma_{frag}$), the associated charged-particle yields opposite to $\\gamma_{dir}$ (away side) are extracted. At mid-rapidity ($|\\eta|<0.9$) in central Au+Au collisions, charged-particle yields associated with $\\gamma_{dir}$ and $\\pi^0$ at high transverse momentum ($8< p_{T}^{trig}<16$ GeV/$c$) are suppressed by a factor of 3-5 compared with $p$ + $p$ collisions. The observed suppression of the associated charged particles, in the kinematic range $|\\eta|<1$ and $3< p_{T}^{assoc} < 16$ GeV/$c$, is similar for $\\gamma_{dir}$ and $\\pi^0$, and independent of the $\\gamma_{dir}$ energy within uncertainties. These measurements indicate that the parton energy loss, in the covered kinematic range, is insensitive to the parton path length.

The STAR Collaboration; B. I. Abelev

2009-12-09T23:59:59.000Z

446

Temperature Dependence of Stark Broadening Dominated by Strong Collisions  

SciTech Connect (OSTI)

The influence of electron temperature in the broadening of spectral lines dominated by strong collisions has been studied. Computer simulation allows us to study the effects of strong and weak collisions separately. Results shown here are focused on some Sr+ and Ba+ resonance lines as examples of lines broadened dominantly by strong collisions. The exact numerical integration of the perturbation process due to the collision with a single particle permits the evaluation of Weisskopf radius. This parameter is usually defined as rw {approx} 1/v {approx} 1/{radical}T, obtained from Bora approximation that is correct for high temperatures. However, at low temperatures the full integration of the collision process permits to test the relationship rw {approx} 1/T1/6. This calculation has allowed us to study the influence of temperature on the broadening of the lines dominated by strong collisions. This study has been done in two ways : through a plasma simulation and analyzing the calculated Weisskopf radius for an individual collision. The obtained results show that at low temperatures the width of the line increases for increasing temperature as a consequence of an increase of the number of collisions not compensated by the decrease of Weisskopf radius.

Gigosos, M. A. [Departamento de Optica, Universidad de Valladolid. 47071 Valladolid (Spain) (Spain); Gonzalez, M. A. [Departamento de Fisica Aplicada, Universidad de Valladolid. 47071 Valladolid (Spain); Konjevic, N. [Institute of Physics, P.O. box 68, 11081 Belgrade (Serbia and Montenegro)

2006-11-22T23:59:59.000Z

447

Onset of radial flow in p+p collisions  

E-Print Network [OSTI]

It has been debated for decades whether hadrons emerging from p+p collisions exhibit collective expansion. The signal of the collective motion in p+p collisions is not as clear/clean as in heavy-ion collisions because of the low multiplicity and large fluctuation in p+p collisions. Tsallis Blast-Wave (TBW) model is a thermodynamic approach, introduced to handle the overwhelming correlation and fluctuation in the hadronic processes. We have systematically studied the identified particle spectra in p+p collisions from RHIC to LHC using TBW and found no appreciable radial flow in p+p collisions below $\\sqrt{s}=900$ GeV. At LHC higher energy of 7 TeV in p+p collisions, the radial flow velocity achieves an average value of $= 0.320\\pm0.005$. This flow velocity is comparable to that in peripheral (40-60%) Au+Au collisions at RHIC. Breaking of the identified particle spectra $m_T$ scaling was also observed at LHC from a model independent test.

Kun Jiang; Yinying Zhu; Weitao Liu; Hongfang Chen; Cheng Li; Lijuan Ruan; Ming Shao; Zebo Tang; Zhangbu Xu

2014-12-23T23:59:59.000Z

448

ENERGY BASED ICE COLLISION FORCES Claude Daley1  

E-Print Network [OSTI]

ENERGY BASED ICE COLLISION FORCES Claude Daley1 1 Memorial University of Newfoundland, St. John's, Newfoundland, Canada A1C 3X5 ABSTRACT Ice collision forces can be determined by energy considerations. A variety of interaction geometry cases are considered. The indentation energy functions for eight different

Daley, Claude

449

ENERGY BASED ICE COLLISION FORCES Claude Daley1  

E-Print Network [OSTI]

1 ENERGY BASED ICE COLLISION FORCES Claude Daley1 1 Memorial University of Newfoundland, St. John's, Newfoundland, Canada A1C 3X5 ABSTRACT Ice collision forces can be determined by energy considerations. A variety of interaction geometry cases are considered. The indentation energy functions for eight different

Daley, Claude

450

Sensorless Robot Collision Detection and Hybrid Force/Motion Control  

E-Print Network [OSTI]

a lightweight robot design [6], possibly with distributed compliant characteristics in the driving system andSensorless Robot Collision Detection and Hybrid Force/Motion Control Alessandro De Luca Raffaella-time detection of collisions between a robot manipulator and obstacles of unknown geometry and location

De Luca, Alessandro

451

Boltzmann-Langevin transport model for heavy-ion collisions  

SciTech Connect (OSTI)

Heavy-ion collisions at intermediate energies exhibit catastrophic phenomena which requires descriptions based on stochastic transport models. First, the Boltzmann-Langevin model, which provides an example of such stochastic approaches, is briefly described. Then, a projection method for obtaining numerical solutions of the Boltzmann-Langevin equation is discussed. Finally, some applications of the model to heavy-ion collisions are presented.

Ayik, S. [Tennessee Technological Univ., Cookeville, TN (United States)]|[Joint Institute for Heavy-Ion Research, Oak Ridge, TN (United States)

1994-06-01T23:59:59.000Z

452

Upsilon Production In p-p Collisions at LHC  

E-Print Network [OSTI]

This is a continuation of recent studies of $\\Upsilon(nS)$ production at the LHC in p-p collisions. Our previous studies were for 2.76 TeV, while the present predictions are for 7.0 TeV collisions.

Leonard S. Kisslinger

2012-02-17T23:59:59.000Z

453

Electron-ion collisions in intensely illuminated plasmas G. Shvetsa)  

E-Print Network [OSTI]

Electron-ion collisions in intensely illuminated plasmas G. Shvetsa) and N. J. Fisch Princeton, the collisions of electrons with ions can be made more frequent or less frequent, depending on the polarization to the size of the electron oscillation in the hf field. The stimulated bremsstrahlung emission is calculated

454

Deuteron-nucleus collisions in a multiphase transport model  

E-Print Network [OSTI]

of protons more than those of kaons or pions. Relative to p+p collisions at same center-of-mass energy per nucleon pair, the effect of final-state interactions on the charged particle transverse momentum spectra in d+Au collisions is much smaller than...

Lin, ZW; Ko, Che Ming.

2003-01-01T23:59:59.000Z

455

University of Washington, Nuclear Physics Laboratory annual report, 1995  

SciTech Connect (OSTI)

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.

NONE

1995-04-01T23:59:59.000Z

456

Beyond Mixing-length Theory: a step toward 321D  

E-Print Network [OSTI]

We present a physical basis for algorithms to replace mixing-length theory (MLT) in stellar evolutionary computations. The 321D procedure is based on three-dimensional (3D) time-dependent solutions of the Navier-Stokes equations, including the Kolmogorov cascade as a sub-grid model of dissipation (implicit large eddy simulations; ILES). We use Reynolds-averaged Navier-Stokes (RANS) averaging to make 3D simulation data concise, and use 3D simulations to give RANS closure. We sketch a simple algorithm, which is non-local and time-dependent, with both MLT and the Lorenz convective roll as particular subsets of solutions. The damping length is determined from a balance between the large-scale driving and damping at the Kolmogorov scale. We find that (1) braking regions (boundary layers in which mixing occurs) automatically appear {\\it beyond} the edges of convection as defined by the Schwarzschild criterion, (2) dynamic (non-local) terms imply a non-zero turbulent kinetic energy flux (unlike MLT), (3) the effects...

Arnett, W David; Viallet, Maxime; Campbell, Simon W; Lattanzio, John; Mo?ak, Miroslav

2015-01-01T23:59:59.000Z

457

INSTITUTE OF PHYSICS PUBLISHING JOURNAL OF PHYSICS G: NUCLEAR AND PARTICLE PHYSICS J. Phys. G: Nucl. Part. Phys. 29 (2003) 769775 PII: S0954-3899(03)58133-6  

E-Print Network [OSTI]

distributions of the fragments, knock-out and stripping reactions, Coulomb excitation, etc. Rare nuclear experiments. Correlation experiments with low-energy proton­proton 0954-3899/03/040769+07$30.00 © 2003 IOP. The same happens in nuclear interactions in peripheral collisions, when little energy is transferred

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

458

Neutron interferometric measurement of the scattering length difference between the triplet and singlet states of n-$^3$He  

E-Print Network [OSTI]

We report a determination of the n-$^3$He scattering length difference $\\Delta b^{\\prime} = b_{1}^{\\prime}-b_{0}^{\\prime} = $ ($-5.411$ $\\pm$ $0.031$ (statistical) $\\pm$ $0.039$ (systematic)) fm between the triplet and singlet states using a neutron interferometer. This revises our previous result $\\Delta b^{\\prime} = $ (-5.610 $\\pm$ $0.027$ (statistical) $\\pm$ $0.032$ (systematic) fm obtained using the same technique in 2008. This revision is due to a re-analysis of the 2008 experiment that includes a more robust treatment of the phase shift caused by magnetic field gradients near the $^3$He cell. Furthermore, we more than doubled our original data set from 2008 by acquiring six months of additional data in 2013. Both the new data set and a re-analysis of the older data are in good agreement. Scattering lengths of low Z isotopes are valued for use in few-body nuclear effective field theories, provide important tests of modern nuclear potential models and in the case of $^3$He aid in the interpretation of neutron scattering from quantum liquids. The difference $\\Delta b^{\\prime}$ was determined by measuring the relative phase shift between two incident neutron polarizations caused by the spin-dependent interaction with a polarized $^3$He target. The target $^3$He gas was sealed inside a small, flat windowed glass cell that was placed in one beam path of the interferometer. The relaxation of $^3$He polarization was monitored continuously with neutron transmission measurements. The neutron polarization and spin flipper efficiency were determined separately using $^3$He analyzers and two different polarimetry analysis methods. A summary of the measured scattering lengths for n-$^3$He with a comparison to nucleon interaction models is given.

M. G. Huber; M. Arif; W. C. Chen; T. R. Gentile; D. S. Hussey; T. C. Black; D. A. Pushin; C. B. Shahi; F. E. Wietfeldt; L. Yang

2014-09-30T23:59:59.000Z

459

Isotope Development & Production | Nuclear Science | ORNL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Nuclear Security Science & Technology Nuclear Systems Modeling, Simulation & Validation Nuclear Systems Technology Reactor Technology Nuclear Science Home | Science & Discovery |...

460

Nuclear Structure Aspects in Nuclear Astrophysics  

SciTech Connect (OSTI)

Nuclear Astrophysics as a broad and diverse field of study can be viewed as a magnifier of the impact of microscopic processes on the evolution of macroscopic events. One of the primary goals in Nuclear Astrophysics is the understanding of the nucleosynthesis processes that take place in the cosmos and the simulation of the correlated stellar and explosive burning scenarios. These simulations are strongly dependent on the input from Nuclear Physics which sets the time scale for all stellar dynamic processes--from giga-years of stellar evolution to milliseconds of stellar explosions--and provides the basis for most of the signatures that we have for the interpretation of these events--from stellar luminosities, elemental and isotopic abundances to neutrino flux from distant supernovae. The Nuclear Physics input comes through nuclear structure, low energy reaction rates, nuclear masses, and decay rates. There is a common perception that low energy reaction rates are the most important component of the required nuclear physics input; however, in this article we take a broader approach and present an overview of the close correlation between various nuclear structure aspects and their impact on nuclear astrophysics. We discuss the interplay between the weak and the strong forces on stellar time scales due to the limitations they provide for the evolution of slow and rapid burning processes. The effects of shell structure in nuclei on stellar burning processes as well as the impact of clustering in nuclei is outlined. Furthermore we illustrate the effects of the various nuclear structure aspects on the major nucleosynthesis processes that have been identified in the last few decades. We summarize and provide a coherent overview of the impact of all aspects of nuclear structure on nuclear astrophysics.

Smith, Michael Scott [ORNL

2006-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear collision length" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Wisconsin Nuclear Profile - Point Beach Nuclear Plant  

U.S. Energy Information Administration (EIA) Indexed Site

Point Beach Nuclear Plant" "Unit","Summer capacity (mw)","Net generation (thousand mwh)","Summer capacity factor (percent)","Type","Commercial operation date","License expiration...

462

Tennessee Nuclear Profile - Watts Bar Nuclear Plant  

U.S. Energy Information Administration (EIA) Indexed Site

Watts Bar Nuclear Plant" "Unit","Summer capacity (mw)","Net generation (thousand mwh)","Summer capacity factor (percent)","Type","Commercial operation date","License expiration...

463

Massachusetts Nuclear Profile - Pilgrim Nuclear Power Station  

U.S. Energy Information Administration (EIA) Indexed Site

Pilgrim Nuclear Power Station" "Unit","Summer capacity (mw)","Net generation (thousand mwh)","Summer cpacity factor (percent)","Type","Commercial operation date","License...

464

Arkansas Nuclear Profile - Arkansas Nuclear One  

U.S. Energy Information Administration (EIA) Indexed Site

Nuclear One" "Unit","Summer capacity (mw)","Net generation (thousand mwh)","Summer capacity factor (percent)","Type","Commercial operation date","License expiration date"...

465

Radiation effects in nuclear materials: Role of nuclear and electronic energy losses and their synergy  

SciTech Connect (OSTI)

Ceramic oxides and carbides are promising matrices for the immobilization and/or transmutation of nuclear wastes, cladding materials for gas-cooled fission reactors and structural components for fusion reactors. For these applications there is a need of fundamental data concerning the behavior of nuclear ceramics upon irradiation. This article is focused on the presentation of a few remarkable examples regarding ion-beam modifications of nuclear ceramics with an emphasis on the mechanisms leading to damage creation and phase transformations. Results obtained by combining advanced techniques (Rutherford backscattering spectrometry and channeling, X-ray diffraction, transmission electron microscopy, Raman spectroscopy) concern irradiations in a broad energy range (from keV to GeV) with the aim of exploring both nuclear collision (Sn) and electronic excitation (Se) regimes. Finally, the daunting challenge of the demonstration of the existence of synergistic effects between Sn and Se is tackled by discussing the healing due to intense electronic energy deposition (SHIBIEC) and by reporting results recently obtained in dual-beam irradiation (DBI) experiments.

Thomé, Lionel [Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse, CNRS-IN2P3-Université Paris-Sud; Debelle, Aurelien [Universite Paris Sud, Orsay, France; Garrido, Frederico [Universite Paris Sud, Orsay, France; Mylonas, Stamatis [Universite Paris Sud, Orsay, France; Décamps, B. [Universite Paris Sud, Orsay, France; Bachelet, C. [Universite Paris Sud, Orsay, France; Sattonnay, G. [LEMHE/ICMMO, Université Paris-Sud, Bât. Orsay, France; Moll, Sandra [French Atomic Energy Commission (CEA), Centre de Saclay, Gif sur Yvette; Pellegrino, S. [French Atomic Energy Commission (CEA); Miro, S. [French Atomic Energy Commission (CEA); Trocellier, P. [French Atomic Energy Commission (CEA); Serruys, Y. [French Atomic Energy Commission (CEA); Velisa, G. [French Atomic Energy Commission (CEA); Grygiel, C. [CNRS, France; Monnet, I. [CIMAP, CEA-CNRS-Université de Caen, France; Toulemonde, Marcel [French Atomic Energy Commission (CEA), French National Centre for Scientific Research (CNRS)-ENSICAE; Simon, P. [CEMHTI, CNRS, France; Jagielski, Jacek [Institute for Electronic Materials Technology; Jozwik-Biala, Iwona [Institute for Electronic Materials Technology; Nowicki, Lech [Soltan Institute for Nuclear Studies, Swierk, Poland; Behar, M. [Instituto de Fisica, Universidade Federal do Rio Grande do Sul, Porto Alegre,; Weber, William J [ORNL; Zhang, Yanwen [ORNL; Backman, Marie [University of Tennessee, Knoxville (UTK); Nordlund, Kai [University of Helsinki; Djurabekova, Flyura [University of Helsinki

2013-01-01T23:59:59.000Z

466

Dynamics of nuclear envelope and nuclear pore complex formation  

E-Print Network [OSTI]

Limited expression of nuclear pore membrane glycoprotein 210suggests cell-type specific nuclear pores in metazoans. Expand Dultz, E. (2008). Nuclear pore complex assembly through

Anderson, Daniel J.

2008-01-01T23:59:59.000Z

467

The Nuclear Revolution, Relative Gains, and International Nuclear Assistance  

E-Print Network [OSTI]

Organizations, accidents, and nuclear weapons. Princeton,the likelihood of a nuclear accident (Sagan 1993, 1995). “potential for a nuclear accident. Yet it seems implausible

Kroenig, Matthew

2006-01-01T23:59:59.000Z

468

The Nuclear Revolution, Relative Gains, and International Nuclear Assistance  

E-Print Network [OSTI]

nature of the nuclear recipient’s security environment. ThisKeywords: Nuclear weapons proliferation; security; securitynature of the nuclear recipient’s security environment. This

Kroenig, Matthew

2006-01-01T23:59:59.000Z

469

Simulations of The Dalles Dam Proposed Full Length Spillwall  

SciTech Connect (OSTI)

This report presents results of a computational fluid dynamics (CFD) modeling study to evaluatethe impacts of a full-length spillwall at The Dalles Dam. The full-length spillwall is being designed and evaluated as a structural means to improve tailrace egress and thus survival of juvenile fish passing through the spillway. During the course of this study, a full-length spillwall at Bays 6/7 and 8/9 were considered. The U.S. Army Corps of Engineers (USACE) has proposed extending the spillwall constructed in the stilling basin between spillway Bays 6 and 7 about 590 ft farther downstream. It is believed that the extension of the spillwall will improve egress conditions for downstream juvenile salmonids by moving them more rapidly into the thalweg of the river hence reducing their exposure to predators. A numerical model was created, validated, and applied the The Dalles Dam tailrace. The models were designed to assess impacts to flow, tailrace egress, navigation, and adult salmon passage of a proposed spill wall extension. The more extensive model validation undertaken in this study greatly improved our confidence in the numerical model to represent the flow conditions in The Dalles tailrace. This study used these validated CFD models to simulate the potential impacts of a spillwall extension for The Dalles Dam tailrace for two locations. We determined the following: (1)The construction of an extended wall (between Bays 6/7) will not adversely impact entering or exiting the navigation lock. Impact should be less if a wall were constructed between Bays 8/9. (2)The construction of a wall between Bays 6/7 will increase the water surface elevation between the wall and the Washington shore. Although the increased water surface elevation would be beneficial to adult upstream migrants in that it decreases velocities on the approach to the adult ladder, the increased flow depth would enhance dissolved gas production, impacting potential operations of the project because of water quality. A wall between Bays 8/9 should have a lesser impact as the confined spill would be across more bays and the relative flow constriction less. (3) The 405 kcfs case was used for the rapid assessment of flow conditions and hydraulic mechanisms that might be responsible for the unexpected erosion at the end of the shelf downstream of Bay 7.

Rakowski, Cynthia L.; Perkins, William A.; Richmond, Marshall C.; Serkowski, John A.

2008-02-25T23:59:59.000Z

470

Sideward Flow in Au + Au Collisions Between 2A GeV and 8A GeV  

E-Print Network [OSTI]

Using the large acceptance Time Projection Chamber of experiment E895 at Brookhaven, measurements of collective sideward flow in Au + Au collisions at beam energies of 2, 4, 6 and 8A GeV are presented in the form of in-plane transverse momentum and the first Fourier coefficient of azimuthal anisotropy v_1. These measurements indicate a smooth variation of sideward flow as a function of beam energy. The data are compared with four nuclear transport models which have an orientation towards this energy range. All four exhibit some qualitative trends similar to those found in the data, although none shows a consistent pattern of agreement within experimental uncertainties.

E895 Collaboration; H. Liu; N. N. Ajitanand; J. Alexander; M. Anderson; D. Best; F. P. Brady; T. Case; W. Caskey; D. Cebra; J. Chance; B. Cole; K. Crowe; A. Das; J. Draper; M. Gilkes; S. Gushue; M. Heffner; A. Hirsch; E. Hjort; L. Huo; M. Justice; M. Kaplan; D. Keane; J. Kintner; J. Klay; D. Krofcheck; R. Lacey; M. A. Lisa; Y. M. Liu; R. McGrath; Z. Milosevich; G. Odyniec; D. Olson; S. Y. Panitkin; N. Porile; G. Rai; H. G. Ritter; J. Romero; R. Scharenberg; L. S. Schroeder; B. Srivastava; N. T. B. Stone; T. J. M. Symons; S. Wang; J. Whitfield; T. Wienold; R. Witt; L. Wood; X. Yang; W. N. Zhang; Y. Zhang

2000-05-24T23:59:59.000Z

471

Simulated nuclear reactor fuel assembly  

DOE Patents [OSTI]

An apparatus for electrically simulating a nuclear reactor fuel assembly. It includes a heater assembly having a top end and a bottom end and a plurality of concentric heater tubes having electrical circuitry connected to a power source, and radially spaced from each other. An outer target tube and an inner target tube is concentric with the heater tubes and with each other, and the outer target tube surrounds and is radially spaced from the heater tubes. The inner target tube is surrounded by and radially spaced from the heater tubes and outer target tube. The top of the assembly is generally open to allow for the electrical power connection to the heater tubes, and the bottom of the assembly includes means for completing the electrical circuitry in the heater tubes to provide electrical resistance heating to simulate the power profile in a nuclear reactor. The embedded conductor elements in each heater tube is split into two halves for a substantial portion of its length and provided with electrical isolation such that each half of the conductor is joined at one end and is not joined at the other end.

Berta, Victor T. (Idaho Falls, ID)

1993-01-01T23:59:59.000Z

472

Simulated nuclear reactor fuel assembly  

DOE Patents [OSTI]

An apparatus for electrically simulating a nuclear reactor fuel assembly. It includes a heater assembly having a top end and a bottom end and a plurality of concentric heater tubes having electrical circuitry connected to a power source, and radially spaced from each other. An outer target tube and an inner target tube is concentric with the heater tubes and with each other, and the outer target tube surrounds and is radially spaced from the heater tubes. The inner target tube is surrounded by and radially spaced from the heater tubes and outer target tube. The top of the assembly is generally open to allow for the electrical power connection to the heater tubes, and the bottom of the assembly includes means for completing the electrical circuitry in the heater tubes to provide electrical resistance heating to simulate the power profile in a nuclear reactor. The embedded conductor elements in each heater tube is split into two halves for a substantial portion of its length and provided with electrical isolation such that each half of the conductor is joined at one end and is not joined at the other end.

Berta, V.T.

1993-04-06T23:59:59.000Z

473

First $?K$ atom lifetime and $?K$ scattering length measurements  

E-Print Network [OSTI]

The results of a search for hydrogen-like atoms consisting of $\\pi^{\\mp}K^{\\pm}$ mesons are presented. Evidence for $\\pi K$ atom production by 24 GeV/c protons from CERN PS interacting with a nickel target has been seen in terms of characteristic $\\pi K$ pairs from their breakup in the same target ($178 \\pm 49$) and from Coulomb final state interaction ($653 \\pm 42$). Using these results the analysis yields a first value for the $\\pi K$ atom lifetime of $\\tau=(2.5_{-1.8}^{+3.0})$ fs and a first model-independent measurement of the S-wave isospin-odd $\\pi K$ scattering length $\\left|a_0^-\\right|=\\frac{1}{3}\\left|a_{1/2}-a_{3/2}\\right|= \\left(0.11_{-0.04}^{+0.09} \\right)M_{\\pi}^{-1}$ ($a_I$ for isospin $I$).

B. Adeva; L. Afanasyev; Y. Allkofer; C. Amsler; A. Anania; S. Aogaki; A. Benelli; V. Brekhovskikh; T. Cechak; M. Chiba; P. Chliapnikov; C. Ciocarlan; S. Constantinescu; P. Doskarova; D. Drijard; A. Dudarev; M. Duma; D. Dumitriu; D. Fluerasu; A. Gorin; O. Gorchakov; K. Gritsay; C. Guaraldo; M. Gugiu; M. Hansroul; Z. Hons; S. Horikawa; Y. Iwashita; V. Karpukhin; J. Kluson; M. Kobayashi; V. Kruglov; L. Kruglova; A. Kulikov; E. Kulish; A. Kuptsov; A. Lamberto; A. Lanaro; R. Lednicky; C. Marińas; J. Martincik; L. Nemenov; M. Nikitin; K. Okada; V. Olchevskii; M. Pentia; A. Penzo; M. Plo; T. Ponta; P. Prusa; G. Rappazzo; A. Romero Vidal; A. Ryazantsev; V. Rykalin; J. Schacher; A. Sidorov; J. Smolik; S. Sugimoto; F. Takeutchi; L. Tauscher; T. Trojek; S. Trusov; T. Urban; T. Vrba; V. Yazkov; Y. Yoshimura; M. Zhabitsky; P. Zrelov

2014-03-04T23:59:59.000Z

474

Characteristic length of an AdS/CFT superconductor  

E-Print Network [OSTI]

We investigate in more detail the holographic model of a superconductor recently found by Hartnoll, Herzog, and Horowitz [Phys. Rev. Lett. 101, 031601], which is constructed from a condensate of a charged scalar field in AdS_4-Schwarzschild background. By analytically studying the perturbation of the gravitational system near the critical temperature T_c, we obtain the superconducting coherence length proportional to 1/\\sqrt{1-T/T_c} via AdS/CFT correspondence. By adding a small external homogeneous magnetic field to the system, we find that a stationary diamagnetic current proportional to the square of the order parameter is induced by the magnetic field. These results agree with Ginzburg-Landau theory and strongly support the idea that a superconductor can be described by a charged scalar field on a black hole via AdS/CFT duality.

Kengo Maeda; Takashi Okamura

2008-10-30T23:59:59.000Z

475

Light absorption cell combining variable path and length pump  

DOE Patents [OSTI]

A device for use in making spectrophotometric measurements of fluid samples. In particular, the device is a measurement cell containing a movable and a fixed lens with a sample of the fluid therebetween and through which light shines. The cell is connected to a source of light and a spectrophotometer via optic fibers. Movement of the lens varies the path length and also pumps the fluid into and out of the cell. Unidirectional inlet and exit valves cooperate with the movable lens to assure a one-way flow of fluid through the cell. A linear stepper motor controls the movement of the lens and cycles it from a first position closer to the fixed lens and a second position farther from the fixed lens, preferably at least 10 times per minute for a nearly continuous stream of absorption spectrum data.

Prather, William S. (2419 Dickey Rd., Augusta, GA 30906)

1993-01-01T23:59:59.000Z

476

Light absorption cell combining variable path and length pump  

DOE Patents [OSTI]

A device is described for use in making spectrophotometric measurements of fluid samples. In particular, the device is a measurement cell containing a movable and a fixed lens with a sample of the fluid there between and through which light shines. The cell is connected to a source of light and a spectrophotometer via optic fibers. Movement of the lens varies the path length and also pumps the fluid into and out of the cell. Unidirectional inlet and exit valves cooperate with the movable lens to assure a one-way flow of fluid through the cell. A linear stepper motor controls the movement of the lens and cycles it from a first position closer to the fixed lens and a second position farther from the fixed lens, preferably at least 10 times per minute for a nearly continuous stream of absorption spectrum data. 2 figures.

Prather, W.S.

1993-12-07T23:59:59.000Z

477

DHS Internship Summary-Crystal Assembly at Different Length Scales  

SciTech Connect (OSTI)

I was part of a project in which in situ atomic force microscopy (AFM) was used to monitor growth and dissolution of atomic and colloidal crystals. At both length scales, the chemical environment of the system greatly altered crystal growth and dissolution. Calcium phosphate was used as a model system for atomic crystals. A dissolution-reprecipitation reaction was observed in this first system, involving the conversion of brushite (DCPD) to octacalcium phosphate (OCP). In the second system, polymeric colloidal crystals were dissolved in an ionic solvent, revealing the underlying structure of the crystal. The dissolved crystal was then regrown through an evaporative step method. Recently, we have also found that colloids can be reversibly deposited in situ onto an ITO (indium tin oxide) substrate via an electrochemistry setup. The overall goal of this project was to develop an understanding of the mechanisms that control crystallization and order, so that these might be controlled during material synthesis. Controlled assembly of materials over a range of length scales from molecules to nanoparticles to colloids is critical for designing new materials. In particular, developing materials for sensor applications with tailorable properties and long range order is important. In this work, we examine two of these length scales: small molecule crystallization of calcium phosphate (whose crystal phases include DCPD, OCP, and HAP) and colloidal crystallization of Poly(methyl methacrylate) beads. Atomic Force Microscopy is ideal for this line of work because it allows for the possibility of observing non-conducting samples in fluid during growth with high resolution ({approx} 10 nm). In fact, during atomic crystal growth one can observe changes in atomic steps, and with colloidal crystals, one can monitor the individual building blocks of the crystal. Colloids and atoms crystallize under the influence of different forces acting at different length scales as seen in Table 1. In particular, molecular crystals, which are typically dominated by ionic and covalent bonding, are an order of magnitude more strongly bonded than colloidal crystals. In molecular crystals, ordering is driven by the interaction potentials between molecules. By contrast, colloidal assembly is a competition between the repulsive electrostatic forces that prevent aggregation in solution (due to surface charge), and short-range van der Waals and entropic forces that leads to ordering. Understanding atomic crystallization is fundamentally important for fabrication of tailorable crystalline materials, for example for biological or chemical sensors. The transformation of brushite to OCP not only serves as a model system for atomic crystal growth (applicable to many other crystal growth processes), but is also important in bone cements. Colloidal crystals have unique optical properties which respond to chemical and mechanical stimuli, making them very important for sensing applications. The mechanism of colloidal crystal assembly is thus fundamentally important. Our in situ dissolution and regrowth experiments are one good method of analyzing how these crystals pack under different conditions and how defect sites are formed and filled. In these experiments, a silica additive was used to strengthen the colloidal crystal during initial assembly (ex situ) and to increase domain size and long range order. Reversible electrodeposition of colloids onto a conductive substrate (ITO in our case) is another system which can further our knowledge of colloidal assembly. This experiment holds promise of allowing in situ observation of colloidal crystal growth and the influence of certain additives on crystal order. The ultimate goal would be to achieve long range order in these crystals by changing the surface charge or the growth environment.

Mishchenko, L

2009-08-06T23:59:59.000Z

478

Long-length contaminated equipment disposal process path document  

SciTech Connect (OSTI)

The first objective of the LLCE Process Path Document is to guide future users of this system on how to accomplish the cradle-to-grave process for the disposal of long-length equipment. Information will be provided describing the function and approach to each step in the process. Pertinent documentation, prerequisites, drawings, procedures, hardware, software, and key interfacing organizations will be identified. The second objective is related to the decision to lay up the program until funding is made available to complete it or until a need arises due to failure of an important component in a waste tank. To this end, the document will identify work remaining to be completed for each step of the process and open items or issues that remain to be resolved.

McCormick, W.A.

1998-09-30T23:59:59.000Z

479

Pauling bond strength, bond length and electron density distribution. |  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006 TheSteven AshbyDepartment ofGE's E.Gilman AboutPaulPaul Ross