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Related papers: Memory effects in Langevin approach to the nuclear…

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We include in statistical model calculations the facts that in the nuclear multifragmentation process the fragments are produced within a given volume and have a finite size. The corrections associated with these constraints affect the…

Nuclear Theory · Physics 2008-11-26 S. R. Souza , R. Donangelo , W. G. Lynch , M. B. Tsang

While Landauer's Principle sets a lower bound for the work required for a computation, that work is recoverable for efficient computations. However, practical physical computers, such as modern digital computers or biochemical systems, are…

Statistical Mechanics · Physics 2021-04-27 Alexander B. Boyd , Paul M. Riechers , Gregory W. Wimsatt , James P. Crutchfield , Mile Gu

We address the challenge of incorporating non-Markovian electronic friction effects in quantum-mechanical approximations of dynamical observables. A generalized Langevin equation (GLE) is formulated for ring-polymer molecular dynamics…

Materials Science · Physics 2025-06-04 George Trenins , Mariana Rossi

It is analytically shown that the one-dimensional Ising model with Glauber dynamics exhibits short time memory effects when submitted to an abrupt change in the temperature. These effects are qualitatively similar to those experimentally…

Statistical Mechanics · Physics 2009-11-07 J. Javier Brey , A. Prados

Diffusion studies of adsorbates moving on a surface are often analyzed using 2D Langevin simulations. These simulations are computationally cheap and offer valuable insight into the dynamics, however, they simplify the complex interactions…

Materials Science · Physics 2015-05-28 Moshe Diamant , Saar Rahav , Riccardo Ferrando , Gil Alexandrowicz

We present the TDDFT+Langevin model that incorporates microscopic time-dependent density function theory (TDDFT) with macroscopic Langevin model. By extracting the energy-dependent dissipation effect from the TDDFT dynamics, quantum effects…

Nuclear Theory · Physics 2022-04-07 Yoritaka Iwata , Takashi Nishikawa

The mass asymmetry in the fission of U-236 at low excitation energy is clarified by the analysis of the trajectories obtained by solving the Langevin equations for the shape degrees of freedom. It is demonstrated that the position of the…

Nuclear Theory · Physics 2015-06-23 Y. Aritomo , S. Chiba , F. A. Ivanyuk

We propose event by event velocity fluctuations of nuclear fission fragments as an additional interesting observable that gives access to the nuclear temperature in an independent way from spectral measurements and relates the diffusion and…

The time-dependent transmission coefficient for the Kramers problem exhibits different behaviors in different parameter regimes. In the high friction regime it decays monotonically ("non-adiabatic"), and in the low friction regime it decays…

Statistical Mechanics · Physics 2009-10-31 Ramon Reigada , Aldo H. Romero , Katja Lindenberg , Jose M. Sancho

We consider the stochastic dynamics of a system linearly coupled to a hierarchical thermal bath with two well-separated inherent timescales: one slow, and one fast. The slow part of the bath is modeled as a set of harmonic oscillators and…

Statistical Mechanics · Physics 2019-06-05 A. V. Plyukhin

We analyzed the total kinetic energy (TKE) of fission fragments with three-dimensional Langevin calculations for a series of actinides and Fm isotopes at various excitation energies. This allowed us to establish systematic trends of TKE…

Nuclear Theory · Physics 2018-01-17 Mark Dennis Usang , Fedir Ivanyuk , Chikako Ishizuka , Satoshi Chiba

Accounting for viscous damping within Fokker-Planck equations led to various improvements in the understanding and analysis of nuclear fission of heavy nuclei. Analytical expressions for the fission time are typically provided by Kramers'…

Nuclear Theory · Physics 2017-12-06 Chris Eccles , Sanil Roy , Thomas H. Gray , Alessio Zaccone

Previous years researchers began to simulate open quantum system, taking into account the interaction between system and the environment. One approach to deal with this problem is to use the density matrix within the Liouville-von-Neumann…

Quantum Physics · Physics 2025-09-15 Mohammad Attrash , Roi Baer

A new experimental approach is introduced to investigate the relaxation of the nuclear deformation degrees of freedom. Highly excited fissioning systems with compact shapes and low angular momenta are produced in peripheral relativistic…

Nuclear Experiment · Physics 2009-11-10 B. Jurado , C. Schmitt , K. -H. Schmidt , J. Benlliure , T. Enqvist , A. R. Junghans , A. Kelic , F. Rejmund

Multifragmentation in Au+Au collisions is investigated at incident energies in the range 100-400 MeV per nucleon by means of a recently developed quantal Langevin model. The inclusion of quantum fluctuations enhances the average…

Nuclear Theory · Physics 2009-10-30 A. Ohnishi , J. Randrup

The steady state of a Langevin equation with short ranged memory and coloured noise is analyzed. When the fluctuation-dissipation theorem of second kind is not satisfied, the dynamics is irreversible, i.e. detailed balance is violated. We…

Statistical Mechanics · Physics 2015-05-13 Andrea Puglisi , Dario Villamaina

Memory effects are a key feature in the description of the dynamical systems governed by the generalized Langevin equation, which presents an exact reformulation of the equation of motion. A simple measure for the estimation of memory…

Disordered Systems and Neural Networks · Physics 2007-05-23 Anatolii V. Mokshin , Renat M. Yulmetyev , Peter Hänggi

The intrinsic excitation energy of fission fragments is dynamically evaluated in terms of the time dependent pairing equations. These equations are corroborated with two conditions. One of them fixes the number of particles and the another…

Nuclear Theory · Physics 2011-06-06 M. Mirea

We investigate whether making the friction spatially dependent on the reaction coordinate introduces quantum effects into the thermal reaction rates for dissipative reactions. Quantum rates are calculated using the numerically exact…

As well known, the generalized Langevin equation with a memory kernel decreasing at large times as an inverse power law of time describes the motion of an anomalously diffusing particle. Here, we focus attention on some new aspects of the…

Statistical Mechanics · Physics 2011-05-27 Noëlle Pottier