References of "Stancu, Floarea"
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See detailOn the exact solutions of the Lipkin-Meshkov-Glick model
Debergh, N.; Stancu, Floarea ULiege

in Journal of Physics: A Mathematical and General (2001), A34

We present the many-particle Hamiltonian model of Lipkin, Meshkov and Glick in the context of deformed polynomial algebras and show that its exact solutions can be easily and naturally obtained within ... [more ▼]

We present the many-particle Hamiltonian model of Lipkin, Meshkov and Glick in the context of deformed polynomial algebras and show that its exact solutions can be easily and naturally obtained within this formalism. The Hamiltonian matrix of each $j$ multiplet can be split into two submatrices associated to two distinct irreps of the deformed algebra. Their invariant subspaces correspond to even and odd numbers of particle-hole excitations. [less ▲]

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See detailProperties of ordinary and exotic hadrons
Stancu, Floarea ULiege

in Few-Body Systems Supplementum (2001), 13

I discuss properties of ordinary and exotic hadrons as described by two distinct constituent quark models. These are the one gluon exchange (OGE) and the Goldstone boson exchange (GBE) models. I also ... [more ▼]

I discuss properties of ordinary and exotic hadrons as described by two distinct constituent quark models. These are the one gluon exchange (OGE) and the Goldstone boson exchange (GBE) models. I also discuss the interaction between hadrons starting from their quark structure. The case of the $NN$ is presented in some details. [less ▲]

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See detailThe short-range baryon baryon interaction in a chiral constituent quark model
Stancu, Floarea ULiege; Glozman, Ya. L.

in Nuclear Physics A (2001), A683

The previous analysis of the short-range $NN$ repulsion originating from the Goldstone boson exchange hyperfine interaction between constituent quarks is revisited. We study in which respects the ... [more ▼]

The previous analysis of the short-range $NN$ repulsion originating from the Goldstone boson exchange hyperfine interaction between constituent quarks is revisited. We study in which respects the repulsion depends on the radial form of the spin-spin quark-quark force. We show that while the radial form affects the structure of the 6Q wave function, the short-range repulsion in the $NN$ system persists in any case. We extend our analysis to other $YN$ and $YY$ (flavor octet-octet) systems and demonstrate that the flavor-spin hyperfine interaction implies a short-range repulsion in these B=2 systems as well. [less ▲]

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See detailSurvey of alternative baryon models
Stancu, Floarea ULiege

Scientific conference (2000, May)

I critically review aspects of the Goldstone boson exchange model and of the algebraic model used in baryon spectroscopy. I discuss their performances with regard to the Roper resonance.

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See detailNucleon-Nucleon scattering in a Chiral Constituent Quark Model
Stancu, Floarea ULiege

in Bled Workshops in Physics (2000), 1(1), 82-84

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See detailOn a q-analogue of the spin-orbit coupling
Micu, M.; Stancu, Floarea ULiege

in Journal of Physics: A Mathematical and General (2000), A33

Based on the tensor method, a $q$-analogue of the spin-orbit coupling is introduced in a $q$-deformed Schr\" odinger equation, previously derived for a central potential. Analytic expressions for the ... [more ▼]

Based on the tensor method, a $q$-analogue of the spin-orbit coupling is introduced in a $q$-deformed Schr\" odinger equation, previously derived for a central potential. Analytic expressions for the matrix elements of the representations $j = \ell \pm 1/2$ are derived. The spectra of the harmonic oscillator and the Coulomb potential are calculated numerically as a function of the deformation parameter, without and with the spin-orbit coupling. The harmonic oscillator spectrum presents strong analogies with the bound spectrum of an Woods-Saxon potential customarily used in nuclear physics. The Coulomb spectrum simulates relativistic effects. The addition of the spin-orbit coupling reinforces this picture. [less ▲]

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See detailOn the scalar meson exchange in the baryon spectra
Stassart, Pierre ULiege; Stancu, Floarea ULiege; Richard, J. M. et al

in Journal of Physics. G, Nuclear and Particle Physics (2000), G26

We explore the role of a scalar meson exchange interaction between quarks in a semirelativistic constituent quark model where the quarks are also subject to a linear confinement. We study how the spectrum ... [more ▼]

We explore the role of a scalar meson exchange interaction between quarks in a semirelativistic constituent quark model where the quarks are also subject to a linear confinement. We study how the spectrum evolves when the strength of the scalar meson exchange increases. Our results are relevant to the long-standing problem of the relative position of the first positive-parity (Roper resonance) and the first orbitally excited states in the baryon spectrum. [less ▲]

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See detailStability of multiquark systems
Stancu, Floarea ULiege

in AIP Conference Proceedings (1999), 508

We give a brief review of developments in the field of exotic hadrons formed of more than three quarks and/or antiquarks. In particular we discuss the stability of multiquark systems containing heavy ... [more ▼]

We give a brief review of developments in the field of exotic hadrons formed of more than three quarks and/or antiquarks. In particular we discuss the stability of multiquark systems containing heavy flavours. We show that the gluon exchange model and the chiral constituent quark model based Goldstone boson (pseudoscalar meson) exchange give entirely different results. [less ▲]

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See detailImportant configurations for NN processes in a Goldstone boson exchange model
Bartz, D.; Stancu, Floarea ULiege

in Physical Review C (1999), C59

We study the short-range nucleon-nucleon interaction in a nonrelativistic chiral constituent quark model by diagonalizing a Hamiltonian containing linear confinement and a Goldstone boson exchange ... [more ▼]

We study the short-range nucleon-nucleon interaction in a nonrelativistic chiral constituent quark model by diagonalizing a Hamiltonian containing linear confinement and a Goldstone boson exchange interaction between quarks. A finite six-quark basis iobtained from single particle cluster model states was previously used. Here we show that the configurations which appear naturally through the use of molecular orbitals, instead of cluster model states, are much more efficient in lowering the six-quark energy. [less ▲]

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See detailStudy of the N N interaction in a Goldstone boson exchange model
Bartz, D.; Stancu, Floarea ULiege

in Physical Review. C, Nuclear Physics (1999), C60

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See detailIsoscalar factors of the permutation group
Stancu, Floarea ULiege; Pepin, S.

in Few-Body Systems (1999), 26

We propose a phase convention for the Clebsch-Gordan coefficients of S_n and present tables of isoscalar factors for S_3,S_4,S_5 and S_6. The isoscalar factors have been calculated from a recursion ... [more ▼]

We propose a phase convention for the Clebsch-Gordan coefficients of S_n and present tables of isoscalar factors for S_3,S_4,S_5 and S_6. The isoscalar factors have been calculated from a recursion relation due to Hamermesh and by using symmetry properties of the Clebsch-Gordan coefficients. Applications of the study of multiquark systems are discussed. [less ▲]

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See detailExotic hadrons
Stancu, Floarea ULiege

in Few-Body Systems Supplementum (1999), 10

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See detailMultiquark states in a Goldstone boson exchange model
Stancu, Floarea ULiege

in Few-Body Systems Supplementum (1999), 11

We discuss the stability of multiquark systems containing heavy flavours. We show that the Goldstone boson exchange model gives results at variance with the one-gluon-exchange models

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See detailPositive parity pentaquarks in a Goldstone boson exchange model
Stancu, Floarea ULiege

in Physical Review. D, Particles and Fields (1998), D58

We study the stability of the pentaquarks $uudd\overline{Q}$, $uuds\overline{Q}$ and $udss\overline{Q}$ ($Q = c$ or $b$) of positive parity in a constituent quark model based on Goldstone boson exchange ... [more ▼]

We study the stability of the pentaquarks $uudd\overline{Q}$, $uuds\overline{Q}$ and $udss\overline{Q}$ ($Q = c$ or $b$) of positive parity in a constituent quark model based on Goldstone boson exchange interaction between quarks. The pentaquark parity is the antiquark parity times that of a quark excited to a p-shell. We show that the Goldstone boson exchange interaction favors these pentaquarks much more than the negative parity ones of the same flavour content but all quarks in the ground state. We find that the nonstrange pentaquarks are stable against strong decays. [less ▲]

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See detailTetraquarks with heavy flavors
Brink, D. M.; Stancu, Floarea ULiege

in Physical Review. D, Particles and Fields (1998), D57

In the framework of a simple nonrelativistic potential model , we have previously studied the stability of a system of two quarks and two antiquarks of identical flavor. Here, we extend our analysis to ... [more ▼]

In the framework of a simple nonrelativistic potential model , we have previously studied the stability of a system of two quarks and two antiquarks of identical flavor. Here, we extend our analysis to quarks (antiquarks) of different masses and discuss the role of heavy flavors on the stability of the system. This analysis is performed by using a simple variational method which proved usefulin the treatment of other few-body systems. We compare our results with other results from the literature and single out a few characteristics of the spectrum of the tetraquarks. [less ▲]

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See detailImportant configurations for NN processes in a Goldstone boson exchange model
Bartz, D.; Stancu, Floarea ULiege

in Proceedings of the 8th International Conference on the Structure of Baryons (1998)

We study the short range nucleon-nucleon interaction in a non-relativistic chiral constituent quark model by diagonalizing a Hamiltonian containing a linear confinement and a Goldston boson exchange ... [more ▼]

We study the short range nucleon-nucleon interaction in a non-relativistic chiral constituent quark model by diagonalizing a Hamiltonian containing a linear confinement and a Goldston boson exchange interaction between quarks. A finite siw-quark basis obtained from single particle cluster model states was previously used. Here we show that the configurations which appear naturally through the use of molecular orbitals, instead of cluster model states, are more efficient in lowering the six-quark energy. [less ▲]

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See detailHeavy hexaquarks in a chiral constituent quark model
Pepin, S.; Stancu, Floarea ULiege

in Physical Review. D, Particles and Fields (1998), D57

We discuss the stability of hexaquark systems of type uuddsQ (Q = c or b) within a chiral constituent quark model which successfully describes the baryon spectra including the charmed ones. We find these ... [more ▼]

We discuss the stability of hexaquark systems of type uuddsQ (Q = c or b) within a chiral constituent quark model which successfully describes the baryon spectra including the charmed ones. We find these systems highly instable against strong decays and give a ccomparison with some of the previous literature. [less ▲]

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See detailHeavy-flavour pentaquarks in a chiral constituent quark model
Genovese, M.; Richard, J. M.; Stancu, Floarea ULiege et al

in Physics Letters B (1998), B425

Within the chiral constituent quark model of Glozman and Riska, we discuss the stability of heavy pentaquarks, i.e. hadrons containing four light quarks and a heavy antiquark. The spin-dependent part of ... [more ▼]

Within the chiral constituent quark model of Glozman and Riska, we discuss the stability of heavy pentaquarks, i.e. hadrons containing four light quarks and a heavy antiquark. The spin-dependent part of the Hamiltonian is dominated by the short-range part of the Goldstone-boson-exchange interaction. We find that these systems are not bound, having an energy above the lowest dissociation threshold into a baryon and a meson. [less ▲]

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See detailHow the *H-particle* unravels the quark dynamics
Stancu, Floarea ULiege; Pepin, S.; Glozman, L Ya

in Physical Review. D, Particles and Fields (1998), D57

It is shown that the short-range part of the Goldstone boson exchange interaction between the constituent quarks, which explains baryon spectroscopy and the short-range repulsion in the NN system, induces ... [more ▼]

It is shown that the short-range part of the Goldstone boson exchange interaction between the constituent quarks, which explains baryon spectroscopy and the short-range repulsion in the NN system, induces a strong short-range repulsion in the flavour-singlet state of the $S=-2$ system with $J^P=0^+$. This suggests that a deeply bound H-particle should not exist. We compare our approach with other models employing different hyperfine interactions between quarks in the nonperturbative regime of QCD. [less ▲]

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See detailQuark substructure approach to 4He charge distribution
Wilets, Lawrence; Alberg, Mary; Pepin, Stéphane et al

in Physical Review. C, Nuclear Physics (1997), 56

We present a study of the 4He charge distribution based on realistic nucleonic wave functions and incorporation of quark substructure. Any central depression of the proton point density seen in modern ... [more ▼]

We present a study of the 4He charge distribution based on realistic nucleonic wave functions and incorporation of quark substructure. Any central depression of the proton point density seen in modern four-body calculations is too small by itself to lead to a correct description of the charge distribution of 4He if folded with a fixed proton size parameter, as is usually done. We utilize six-quark structures calculated in the chromodielectric model for N-N interactions to find a "swelling" of the proton size as the inter-nucleon distance decreases. This swelling is a result of the short-range dynamics in the N-N system. Using the independent pair approximation, the corresponding charge distribution of the proton is folded with the two-nucleon distribution generated from Green's function Monte Carlo calculations of the 4He nucleonic wave function. We obtain a reasonably good fit to the experimental charge distribution of 4He. Meson-exchange currents have not been included. [less ▲]

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