Zobrazeno 1 - 10
of 424
pro vyhledávání: '"Sandulescu, N."'
We study the excited states of zero seniority for various like-particle systems interacting by pairing forces and by general two-body interactions. We consider two types of excitations, generated from a ground state described by a pair condensate. On
Externí odkaz:
http://arxiv.org/abs/2212.08919
We analyse the structure of the ground states of even-even $N>Z$ nuclei with nucleons moving in the same major shell and interacting via realistic two-body forces of shell-model type. We express the ground states of these nuclei as a product of a qua
Externí odkaz:
http://arxiv.org/abs/2212.08002
Autor:
Sambataro, M., Sandulescu, N.
The band structure of N=Z nuclei is constructed from intrinsic states defined in terms of quartets. The simplest of these states is a condensate of collective quartets with isospin T=0. The other intrinsic states are built by promoting one quartet of
Externí odkaz:
http://arxiv.org/abs/2207.14591
Autor:
Sambataro, M., Sandulescu, N.
We provide a description of deformed $N=Z$ nuclei in a formalism of $\alpha$-like quartets. Quartets are constructed variationally by resorting to the use of proper intrinsic states. Various types of intrinsic states are introduced which generate dif
Externí odkaz:
http://arxiv.org/abs/2112.04370
We analyse the contribution of isovector and isoscalar proton-neutron pairing to the binding energies of even-even nuclei with $N-Z=0,2,4$ and atomic mass $20 < A <100$. The binding energies are calculated in the mean-field approach by coupling a Sky
Externí odkaz:
http://arxiv.org/abs/2111.00878
Autor:
Sambataro, M., Sandulescu, N.
Previous studies have shown that the ground state of systems of nucleons composed by an equal number of protons and neutrons interacting via proton-neutron pairing forces can be described accurately by a condensate of $\alpha$-like quartets. Here we
Externí odkaz:
http://arxiv.org/abs/2105.08136
Autor:
Sambataro, M.1 michelangelo.sambataro@ct.infn.it, Sandulescu, N.2 sandulescu@theory.nipne.ro
Publikováno v:
EPJ Web of Conferences. 12/8/2023, Vol. 290, p1-4. 4p.
Publikováno v:
Phys. Rev. C 102, 061301 (2020)
The formal implications of a quartet coherent state ansatz for proton-neutron pairing are analyzed. Its nonlinear annihilation operators, which generalize the BCS linear quasiparticle operators, are computed in the quartetting case. Their structure i
Externí odkaz:
http://arxiv.org/abs/2009.00932
Autor:
Sambataro, M., Sandulescu, N.
The phenomenon of quartet condensation in the ground state of an isovector pairing Hamiltonian for an even-even $N=Z$ system is investigated. For this purpose we follow the evolution of the ground state from an unperturbed regime up to a strongly int
Externí odkaz:
http://arxiv.org/abs/2005.07413
Autor:
Sambataro, M., Sandulescu, N.
We derive the exact $T=0$ seniority-zero eigenstates of the isovector pairing Hamiltonian for an even number of protons and neutrons. Nucleons are supposed to be distributed over a set of non-degenerate levels and to interact through a pairing force
Externí odkaz:
http://arxiv.org/abs/1911.08482