67,201 research outputs found
Brueckner-Hartree-Fock and its renormalized calculations for finite nuclei
We have performed self-consistent Brueckner-Hartree-Fock (BHF) and its
renormalized theory to the structure calculations of finite nuclei. The
-matrix is calculated within the BHF basis, and the exact Pauli exclusion
operator is determined by the BHF spectrum. Self-consistent occupation
probabilities are included in the renormalized Brueckner-Hartree-Fock (RBHF).
Various systematics and convergences are studies. Good results are obtained for
the ground-state energy and radius. RBHF can give a more reasonable
single-particle spectrum and radius. We present a first benchmark calculation
with other {\it ab initio} methods using the same effective Hamiltonian. We
find that the BHF and RBHF results are in good agreement with other
methods
Parton Distributions at Hadronization from Bulk Dense Matter Produced at RHIC
We present an analysis of , , and spectra from
Au+Au collisions at GeV in terms of distributions of
effective constituent quarks at hadronization. Consistency in quark ratios
derived from various hadron spectra provides clear evidence for hadron
formation dynamics as suggested by quark coalescence or recombination models.
We argue that the constituent quark distribution reflects properties of the
effective partonic degrees of freedom at hadronization. Experimental data
indicate that strange quarks have a transverse momentum distribution flatter
than that of up/down quarks consistent with hydrodynamic expansion in partonic
phase prior to hadronization. After the AMPT model is tuned to reproduce the
strange and up/down quark distributions, the model can describe the measured
spectra of hyperons and mesons very well where hadrons are formed
through dynamical coalescence.Comment: 5 pages, 3 figures, two more paragraph added to address the referee's
comment, figure updated to include the KET scale. Accepted version to appear
in Phys. Rev.
Dynamics aspect of subbarrier fusion reaction in light heavy ion systems
Subbarrier fusion of the 7Li + 12C reaction is studied using an
antisymmetrized molecular dynamics model (AMD) with an after burner, GEMINI. In
AMD, 7Li shows an \alpha + t structure at its ground state and it is
significantly deformed. Simulations are made near the Coulomb barrier energies,
i.e., E_{cm} = 3 - 8 MeV. The total fusion cross section of the AMD + GEMINI
calculations as a function of incident energy is compared to the experimental
results and both are in good agreement at E_{cm} > 3 MeV. The cross section for
the different residue channels of the AMD + GEMINI at E_{cm} = 5 MeV is also
compared to the experimental results.Comment: Talk given by Meirong Huang at the 11th International Conference on
Nucleus-Nucleus Collisions (NN2012), San Antonio, Texas, USA, May 27-June 1,
2012. To appear in the NN2012 Proceedings in Journal of Physics: Conference
Series (JPCS
Statistical nature of cluster emission in nuclear liquid-vapour phase coexistence
The emission of nuclear clusters is investigated within the framework of
isospin dependent lattice gas model and classical molecular dynamics model. It
is found that the emission of individual cluster which is heavier than proton
is almost Poissonian except near the transition temperature at which the system
is leaving the liquid-vapor phase coexistence and the thermal scaling is
observed by the linear Arrhenius plots which is made from the average
multiplicity of each cluster versus the inverse of temperature in the liquid
vapor phase coexistence. The slopes of the Arrhenius plots, {\it i.e.} the
"emission barriers", are extracted as a function of the mass or charge number
and fitted by the formula embodied with the contributions of the surface energy
and Coulomb interaction. The good agreements are obtained in comparison with
the data for low energy conditional barriers. In addition, the possible
influences of the source size, Coulomb interaction and "freeze-out" density and
related physical implications are discussed
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