109 documents found, page 1 of 11
Modeling dark matter halos with nonlinear field theories
Correa, R. A.C.; Moraes, P. H.R.S.; De Souza Dutra, A. [UNESP]; Dors, O. L.; De Paula, W.; Frederico, T.Made available in DSpace on 2022-04-28T19:40:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-05-15; In the present work, we adopt a nonlinear scalar field theory coupled to the gravity sector to model galactic dark matter. We find analytical solutions for the scalar field considering the weak field gravity limit, which is usually done in galaxy rotation curves analysis and in order to do so we assume ...
Relativistic dynamics of Qqq systems
Suisso, E. F.; de Melo, J. P. [UNESP]; Frederico, T.Made available in DSpace on 2022-04-28T19:55:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-05-01; The bound state of constituent quarks forming a Qqq composite baryon is investigated in a QCD-inspired effective light-front model. The light-front Faddeev equations are derived and solved numerically. The masses of the spin 1/2 low-lying states of the nucleon, Λ0, Λc+ and Λb0, are found and compared to...
Stability of atomic condensed systems with attractive two-body interactions
Tomio, L. [UNESP]; Filho, V. S. [UNESP]; Gammal, A.; Frederico, T.Made available in DSpace on 2022-04-28T19:55:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-04-01; In the present report, we review recent investigations that we have conducted on the stability of atomic condensed systems, when the two-body interaction is attractive. In particular, the dynamics that occurs in the condensate due to nonconservative terms is considered in the context of an extension of ...
Model for asymptotic D-state parameters of light nuclei: Application to He4
Adhikari, Sadhan K. [UNESP]; Frederico, T.; Goldman, I. D.; Sharma, S. ShellyMade available in DSpace on 2022-04-28T19:59:54Z (GMT). No. of bitstreams: 0 Previous issue date: 1994-01-01; A simple method for calculating the asymptotic D-state observables for light nuclei is suggested. The method exploits the dominant clusters of the light nuclei. The method is applied to calculate the He4 asymptotic D to S normalization ratio and the closely related D-state parameter D2. The study predic...
Model independence of scattering of three identical bosons in two dimensions
Adhikari, Sadhan K. [UNESP]; Delfino, A.; Frederico, T.; Tomio, Lauro [UNESP]Made available in DSpace on 2022-04-28T19:59:54Z (GMT). No. of bitstreams: 0 Previous issue date: 1993-01-01; Within the framework of scattering integral equations in momentum space, we present numerical results of scattering of three identical bosons at low energies in two dimensions for short-range separable potentials. An analysis of the present numerical results reveals the three-particle scattering observa...
Stability of trapped Bose-Einstein condensates
Abdullaev, F. Kh [UNESP]; Gammal, A. [UNESP]; Tomio, Lauro [UNESP]; Frederico, T.Made available in DSpace on 2022-04-28T20:00:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2001-01-01; In three-dimensional trapped Bose-Einstein condensate (BEC), described by the time-dependent Gross-Pitaevskii-Ginzburg equation, we study the effect of initial conditions on stability using a Gaussian variational approach and exact numerical simulations. We also discuss the validity of the criterion for...
Long range local effective potential for a three-particle system
Delfino, A.; Frederico, T.; Tomio, Lauro [UNESP]Made available in DSpace on 2022-04-28T20:01:33Z (GMT). No. of bitstreams: 0 Previous issue date: 1988-01-01; We derive the long- range behavior of an effective interaction for a system with three identical particles. We start our derivation from the zero range theory in configuration space and we show that the asymptotic effective potential, in the relative distance of the subsystem to the third particle, goes...
Relativistic three-particle scattering equations
Adhikari, Sadhan K. [UNESP]; Tomio, Lauro [UNESP]; Frederico, T.Made available in DSpace on 2022-04-28T20:01:34Z (GMT). No. of bitstreams: 0 Previous issue date: 1993-01-01; We derive a set of relativistic three-particle scattering equations in the three-particle c.m. frame employing a relativistic three-particle propagator suggested long ago by Ahmadzadeh and Tjon in the c.m. frame of a two-particle subsystem. We make the coordinate transformation of this propagator from t...
Neutron-neutron correlation in the halo dissociation of light exotic nuclei
Yamashita, M. T. [UNESP]; Frederico, T.; Tomio, Lauro [UNESP]Made available in DSpace on 2022-04-28T20:01:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-07-01; We present model results for the two-halo-neutron correlation functions, Cnn, for the dissociation process of light exotic nuclei modelled as two neutrons and a core. A minimum is predicted for Cnn as a function of the relative momentum of the two neutrons, pnn, due to the coherence of the neutrons in t...
Inclusive annihilation of antiprotons on deuterium
Frederico, T.; Carlson, B. V.; Mastroleo, R. C.; Tomio, Lauro [UNESP]; Hussein, M. S.Made available in DSpace on 2022-04-28T20:03:09Z (GMT). No. of bitstreams: 0 Previous issue date: 1990-01-01; The inclusive annihilation of antiprotons on deuterium is calculated within a three-body model. At very low antiproton energies (Ep»<2.2 MeV), structure is observed in the energy spectra of emerging protons at forward angles. The theory can be easily extended to higher antiproton energies. © 1990 The Am...