Search results for "Statistical physic"
showing 10 items of 1403 documents
Unified framework for generalized and transverse-momentum dependent parton distributions within a 3Q light-cone picture of the nucleon
2011
We present a systematic study of generalized transverse-momentum dependent parton distributions (GTMDs). By taking specific limits or projections, these GTMDs yield various transverse-momentum dependent and generalized parton distributions, thus providing a unified framework to simultaneously model different observables. We present such simultaneous modeling by considering a light-cone wave function overlap representation of the GTMDs. We construct the different quark-quark correlation functions from the 3-quark Fock components within both the light-front constituent quark model as well as within the chiral quark-soliton model. We provide a comparison with available data and make prediction…
Elliptic flow from event-by-event hydrodynamics
2011
We present an event-by-event hydrodynamical framework which takes into account the initial density fluctuations arising from a Monte Carlo Glauber model. The elliptic flow is calculated with the event plane method and a one-to-one comparison with the measured event plane $v_2$ is made. Both the centrality- and $p_T$-dependence of the $v_2$ are remarkably well reproduced. We also find that the participant plane is a quite good approximation for the event plane.
An explanation of the Δ D 35 (1930) as a σΔ bound state
2009
Constituent quark models based on two-body potentials systematically overpredict the mass of ΔD35 (1930). A possible solution to this problem comes out from the application of a schematic hybrid model, containing three-quark as well as meson-baryon components, to the light-quark baryon spectrum. The ΔD35 (1930) and its partners ΔD33 (1940) and ΔD31 (1900) are found to contain a significant σΔ component. Then, through the use of the hidden gauge formalism, it is shown that these resonances can be dynamically generated from the σ-Δ interaction. In particular ΔD35 (1930) can be interpreted as being essentially a σΔ bound state. This interpretation suggests that the inclusion of σΔ as an effect…
Three-Dimensional 3-State Potts Model Revisited With New Techniques
1997
We report a fairly detailed finite-size scaling analysis of the first-order phase transition in the three-dimensional 3-state Potts model on cubic lattices with emphasis on recently introduced quantities whose infinite-volume extrapolations are governed `only' by exponentially small terms. In these quantities no asymptotic power series in the inverse volume are involved which complicate the finite-size scaling behaviour of standard observables related to the specific-heat maxima or Binder-parameter minima. Introduced initially for strong first-order phase transitions in q-state Potts models with ``large enough'' q, the new techniques prove to be surprisingly accurate for a q value as small …
Uncertainty propagation within the UNEDF models
2016
The parameters of the nuclear energy density have to be adjusted to experimental data. As a result they carry certain uncertainty which then propagates to calculated values of observables. In the present work we quantify the statistical uncertainties of binding energies, proton quadrupole moments, and proton matter radius for three UNEDF Skyrme energy density functionals by taking advantage of the knowledge of the model parameter uncertainties. We find that the uncertainty of UNEDF models increases rapidly when going towards proton or neutron rich nuclei. We also investigate the impact of each model parameter on the total error budget.
On the variational approach to Jastrow correlations in nuclei
1973
The variational equation determining the Jastrow correlation function is investigated with particular emphasis on the healing problem for both nuclear matter and finite nuclei. The consequences of several healing conditions are discussed. Furthermore, influences from the choice of the single particle basis and from long range correlations are studied and are found to be small in the short range region.
A sum-rule approach to nuclear ground state correlations
1985
By combining the sum-rule approximation to nuclear giant resonances with a generator-coordinate description of the collective ground-state we obtain a simple estimate of the collective ground-state correlations. We investigate the approach for a variety of nuclei and forces. The correlation effects are small but not negligible in view of the precision achieved in modern Skyrme-Hartree-Fock calculations.
Thermodynamic consistency of the equation of state of strongly interacting matter
2004
Addressing strongly interacting matter in the region of energy density where the hadronic gas phase coexists with the quark-gluon plasma phase, we discuss how thermodynamic consistency can be used to constrain the equation of state for uniform matter and we illustrate the method by constructing a T{sub c}-dependent family of thermodynamically consistent equations of state based on simple spline interpolations between the gas and plasma phases.
The r-process in the high entropy bubble
1997
We examined the r-process in the high entropy bubble within a detailed parameter study. Previous investigations ([1,2]) based on realistic supernovae models showed already that this model yields a very good fit to the solar system r-process abundance curve for masses above A = 120. For A < 120 their fit was relatively poor. We are concerned mainly with the question whether it is possible to obtain a good fit in the range below A = 120. Within a simple approach of an adiabatically expanding sphere we analyzed a broad parameter range, independent of specific explosion simulations. We varyied the electron abundance Ye and the entropy S and studied the resulting contributions as a function of t…
Modified Boltzmann Transport Equation
2005
Recently several works have appeared in the literature in which authors try to describe Freeze Out (FO) in energetic heavy ion collisions based on the Boltzmann Transport Equation (BTE). The aim of this work is to point out the limitations of the BTE, when applied for the modeling of FO or other very fast process, and to propose the way how the BTE approach can be generalized for such a processes.