References of "Stancu, Floarea"      in Complete repository Arts & humanities   Archaeology   Art & art history   Classical & oriental studies   History   Languages & linguistics   Literature   Performing arts   Philosophy & ethics   Religion & theology   Multidisciplinary, general & others Business & economic sciences   Accounting & auditing   Production, distribution & supply chain management   Finance   General management & organizational theory   Human resources management   Management information systems   Marketing   Strategy & innovation   Quantitative methods in economics & management   General economics & history of economic thought   International economics   Macroeconomics & monetary economics   Microeconomics   Economic systems & public economics   Social economics   Special economic topics (health, labor, transportation…)   Multidisciplinary, general & others Engineering, computing & technology   Aerospace & aeronautics engineering   Architecture   Chemical engineering   Civil engineering   Computer science   Electrical & electronics engineering   Energy   Geological, petroleum & mining engineering   Materials science & engineering   Mechanical engineering   Multidisciplinary, general & others Human health sciences   Alternative medicine   Anesthesia & intensive care   Cardiovascular & respiratory systems   Dentistry & oral medicine   Dermatology   Endocrinology, metabolism & nutrition   Forensic medicine   Gastroenterology & hepatology   General & internal medicine   Geriatrics   Hematology   Immunology & infectious disease   Laboratory medicine & medical technology   Neurology   Oncology   Ophthalmology   Orthopedics, rehabilitation & sports medicine   Otolaryngology   Pediatrics   Pharmacy, pharmacology & toxicology   Psychiatry   Public health, health care sciences & services   Radiology, nuclear medicine & imaging   Reproductive medicine (gynecology, andrology, obstetrics)   Rheumatology   Surgery   Urology & nephrology   Multidisciplinary, general & others Law, criminology & political science   Civil law   Criminal law & procedure   Criminology   Economic & commercial law   European & international law   Judicial law   Metalaw, Roman law, history of law & comparative law   Political science, public administration & international relations   Public law   Social law   Tax law   Multidisciplinary, general & others Life sciences   Agriculture & agronomy   Anatomy (cytology, histology, embryology...) & physiology   Animal production & animal husbandry   Aquatic sciences & oceanology   Biochemistry, biophysics & molecular biology   Biotechnology   Entomology & pest control   Environmental sciences & ecology   Food science   Genetics & genetic processes   Microbiology   Phytobiology (plant sciences, forestry, mycology...)   Veterinary medicine & animal health   Zoology   Multidisciplinary, general & others Physical, chemical, mathematical & earth Sciences   Chemistry   Earth sciences & physical geography   Mathematics   Physics   Space science, astronomy & astrophysics   Multidisciplinary, general & others Social & behavioral sciences, psychology   Animal psychology, ethology & psychobiology   Anthropology   Communication & mass media   Education & instruction   Human geography & demography   Library & information sciences   Neurosciences & behavior   Regional & inter-regional studies   Social work & social policy   Sociology & social sciences   Social, industrial & organizational psychology   Theoretical & cognitive psychology   Treatment & clinical psychology   Multidisciplinary, general & others     Showing results 61 to 80 of 136     1 2 3 4 5 6 7     On the exact solutions of the Lipkin-Meshkov-Glick modelDebergh, N.; Stancu, Floarea in Journal of Physics: A Mathematical and General (2001), A34We 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 ▲]Detailed reference viewed: 32 (2 ULiège) Properties of ordinary and exotic hadronsStancu, Floarea in Few-Body Systems Supplementum (2001), 13I 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 ▲]Detailed reference viewed: 17 (6 ULiège) The short-range baryon baryon interaction in a chiral constituent quark modelStancu, Floarea ; Glozman, Ya. L.in Nuclear Physics A (2001), A683The 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 ▲]Detailed reference viewed: 26 (5 ULiège) Survey of alternative baryon modelsStancu, Floarea 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.Detailed reference viewed: 30 (22 ULiège) Nucleon-Nucleon scattering in a Chiral Constituent Quark ModelStancu, Floarea in Bled Workshops in Physics (2000), 1(1), 82-84Detailed reference viewed: 34 (10 ULiège) On a q-analogue of the spin-orbit couplingMicu, M.; Stancu, Floarea in Journal of Physics: A Mathematical and General (2000), A33Based 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 ▲]Detailed reference viewed: 9 (3 ULiège) On the scalar meson exchange in the baryon spectraStassart, Pierre ; Stancu, Floarea ; Richard, J. M. et alin Journal of Physics. G, Nuclear and Particle Physics (2000), G26We 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 ▲]Detailed reference viewed: 24 (7 ULiège) Stability of multiquark systemsStancu, Floarea in AIP Conference Proceedings (1999), 508We 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 ▲]Detailed reference viewed: 24 (6 ULiège) Important configurations for NN processes in a Goldstone boson exchange modelBartz, D.; Stancu, Floarea in Physical Review C (1999), C59We 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 ▲]Detailed reference viewed: 19 (5 ULiège) Study of the N N interaction in a Goldstone boson exchange modelBartz, D.; Stancu, Floarea in Physical Review. C, Nuclear Physics (1999), C60Detailed reference viewed: 16 (3 ULiège) Isoscalar factors of the permutation groupStancu, Floarea ; Pepin, S.in Few-Body Systems (1999), 26We 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 ▲]Detailed reference viewed: 21 (1 ULiège) Exotic hadronsStancu, Floarea in Few-Body Systems Supplementum (1999), 10Detailed reference viewed: 21 (5 ULiège) Multiquark states in a Goldstone boson exchange modelStancu, Floarea in Few-Body Systems Supplementum (1999), 11We 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 modelsDetailed reference viewed: 21 (4 ULiège) Positive parity pentaquarks in a Goldstone boson exchange modelStancu, Floarea in Physical Review. D, Particles and Fields (1998), D58We 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 ▲]Detailed reference viewed: 25 (11 ULiège) Tetraquarks with heavy flavorsBrink, D. M.; Stancu, Floarea in Physical Review. D, Particles and Fields (1998), D57In 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 ▲]Detailed reference viewed: 30 (14 ULiège) Important configurations for NN processes in a Goldstone boson exchange modelBartz, D.; Stancu, Floarea 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 ▲]Detailed reference viewed: 14 (2 ULiège) Heavy hexaquarks in a chiral constituent quark modelPepin, S.; Stancu, Floarea in Physical Review. D, Particles and Fields (1998), D57We 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 ▲]Detailed reference viewed: 24 (2 ULiège) Heavy-flavour pentaquarks in a chiral constituent quark modelGenovese, M.; Richard, J. M.; Stancu, Floarea et alin Physics Letters B (1998), B425Within 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 ▲]Detailed reference viewed: 11 (1 ULiège) How the *H-particle* unravels the quark dynamicsStancu, Floarea ; Pepin, S.; Glozman, L Yain Physical Review. D, Particles and Fields (1998), D57It 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 ▲]Detailed reference viewed: 9 (1 ULiège) Quark substructure approach to 4He charge distributionWilets, Lawrence; Alberg, Mary; Pepin, Stéphane et alin Physical Review. C, Nuclear Physics (1997), 56We 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 ▲]Detailed reference viewed: 22 (2 ULiège)