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Semileptonic bc to cc and bb to bc baryon decays and heavy quark spin symmetry

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Chinese Physics C 2010年第9期34卷 1364-1367页

作者： J.Nieves J.M.flynn e.Hernández Instituto de física corpuscular (IfIC) Centro Mixto Universidad de Valencia-CSICInstitutos de Investigación de Paterna School of Physics and Astronomy University of Southampton departamento de física fundamental e iuffym Universidad de Salamanca

We study the semileptonic decays of the lowest-lying bc baryons to the lowest-lying cc baryons （Ξ （＊） bc → Ξ （＊） cc and Ω （＊） bc → Ω （＊） cc ）,in the limit m b,m c Λ QCD and close to the zero recoil *** separate heavy quark spin symmetries make it possible to describe all these decays using a single form *** also show how these constraints can be used to test the validity of different quark model *** to bc baryon decays are also discussed.

关键词： heavy quark spin symmetry semileptonic decays constituent quark modelsIf

Triply heavy baryons in the constituent quark model

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Chinese Physics C 2020年第2期44卷 33-41页

作者： Gang Yang Jialun Ping Pablo GOrtega Jorge Segovia department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics Tsinghua UniversityBeijing 100084China department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal UniversityNanjing 210023China Grupo de física Nuclear and Instituto Universitario de física fundamental y Matemáticas(iuffym) Universidad de SalamancaE-37008 SalamancaSpain departamento de Sistemas físicos Químicos y NaturalesUniversidad Pablo de OlavideE-41013 SevillaSpain

The constituent quark model is used to compute the ground and excited state masses of QQQ baryons containing either c or b *** quark model parameters previously used to describe the properties of charmonium and bottomonium states were used in this *** non-relativistic three-body bound state problem is solved by means of the Gaussian expansion method which provides sufficient accuracy and simplifies the subsequent evaluation of the matrix *** low-lying states with quantum numbers J^P=1/2^±,3/2^±,5/2^±and 7/2^+are *** compare the results with those obtained by the other theoretical *** is a general agreement for the mass of the ground state in each sector of triply heavy ***,the situation is more puzzling for the excited states,and appropriate comments about the most relevant features of our comparison are given.

关键词： Quantum Chromodynamics quark models properties of baryons exotic baryons

ΛΛN−ΞNN S wave resonance

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Chinese Physics C 2020年第10期44卷 124-128页

作者： H.Garcilazo A.Valcarce escuela Superior de física y Matemáticas Instituto Politécnico NacionalEdificio 907738 México D.F.Mexico departamento de física fundamental Universidad de Salamanca37008 SalamancaSpain

We use an existing model of theΛΛN−ΞNN three-body system based on two-body separable interactions to study the(I,JP)=(1/2,1/2+)three-body *** theΛΛ,ΞN,andΛΛ−ΞN amplitudes,we have constructed separable potentials based on the most recent results of the HAL QCD *** are characterized by the existence of a resonance just below or above theΞN threshold in the H-dibaryon channel,(i,jp)=(0,0+).A three-body resonance appears 2.3 MeV above theΞd *** show that if theΛΛ−ΞN H-dibaryon channel is not considered,theΛΛN−ΞNN S wave resonance ***,the possible existence of aΛΛN−ΞNN resonance would be sensitive to theΛΛ−ΞN *** existence or nonexistence of this resonance could be evidenced by measuring,for example,theΞd cross section.

关键词： baryon-baryon interactions faddeev equations

Stellar Structure Model in the Post-Newtonian Approximation

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Research in Astronomy and Astrophysics 2022年第12期22卷 232-238页

作者： Gilberto M.Kremer departamento de física Universidade Federal do ParanáCuritiba 81531Brazil

In this work the influence of the post-Newtonian corrections to the equations of stellar structure are *** post-Newtonian Lane-emden equation follows from the corresponding momentum density balance *** a polytropic equation of state the solutions of the Lane-emden equations in the Newtonian and post-Newtonian theories are determined and the physical quantities for the Sun,the white dwarf Sirius B and neutron stars with masses M■1.4 M_(⊙),1.8 M_(⊙)and 2.0 M_(⊙)are *** is shown that the post-Newtonian corrections to the fields of mass density,pressure and temperature are negligible for the Sun and Sirius B,but for stars with strong fields the differences become *** the neutron stars analyzed here the central pressure and the central temperature which follow from the post-Newtonian Lane-emden equation are about fifty to sixty percent greater than those of the Newtonian theory and the central mass density is about three to four percent smaller.

关键词： stars:neutron stars:fundamental parameters hydrodynamics

Is X(3872) a bound state?

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Chinese Physics C 2019年第12期43卷 115-120页

作者： Pablo G.Ortega enrique Ruiz Arriola Grupo de fisica Nuclear and Instituto Universitario de fisica fundamental y Matematicas(iuffym) Universidad de SalamancaE-37008 SalamancaSpain departamento de fisica Atomica Molecular y Nuclear and Instituto Carlos I de Fisica Teorica y ComputacionalUniversidad de GranadaE-18071 GranadaSpain

All existing experimental evidence for the bound state nature of X(3872)relies on observing its decay products,which are measured with a finite experimental mass resolution that is typically△m≥2 MeV,and much larger than its alleged binding energy,BX=0.00(18)*** the other hand,we have found recently that there is a clear cancellation in the 1^++channel of the invariant DD^*mass around the threshold between continuum and the bound *** is very much like a similar cancellation in the proton-neutron continuum with the deuteron in the 1^++*** on comparative fits with a common Tsallis distribution of the experimental cross-sections for prompt production of deuterons and X(3872)in pp collisions with a finite pT,we find a strong argument for questioning the bound state nature of this state,which also suggests that the large observed production rate could be consistent with a half-bound state.

关键词： charmonium molecular states particle production Tsallis distribution

Hadron resonances as rovibrational states

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Chinese Physics C 2021年第8期45卷 99-104页

作者： Douglas L.Bernardo Cristiano C.Bastos Antonio C.Pavao departamento de Quimica fundamental Universidade Federal de PernambucoRecife50740-540Brazil departamento de Quimica Universidade Federal Rural de PernambucoRecife52171-900Brazil

A rovibrational model,including anharmonic,centrifugal,and Coriolis corrections,is used to calculate π,K,N,and ∑ orbital and radial *** four orbital excitations of the n meson correspond to the/?(1235),ti2(1670),63(2030),and π4(2250)*** first four radial excitations correspond to the π(1300),π(1800),π(2070),and 7t(2360)*** orbital excitations of the K meson are interpreted as the K_(1)(1270),K_(2)(1770),K_(3)(2320),and K_(4)(2500)resonances;its radial excitations correspond to the K(1460)and K(1830)*** N orbital excitations are identified with the N(1520),N(1680),N(2190),N(2220),and N(2600)*** first four radial excitations of the N family correspond to the N(1440),N(1880),N(2100),and N(2300)*** orbital excitations of the ∑ baryon are associated with the ∑(1670),∑(1915),∑(2100),and ∑(2250)resonances,whereas its radial excitations are identified with the ∑(1660),∑(1770),and ∑(1880)*** proposed rovibrational model calculations show a good agreement with the corresponding experimental values and allow for the prediction of hadron resonances,thereby proving to be useful for the interpretation of excited hadron spectra.

关键词： excited hadron spectrum orbital and radial resonances rovibrational states

Comparison between the theoretical models and experimental structures of some oc tacoordinated Ln(Ⅲ)-bis-dipyridyl-bis-dichloroacetato-diaquo complexes and their phenanthroline analogues

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Journal of Rare earths 2010年第S1期28卷 83-85页

作者： S. P. SINHA Alfredo M. SIMAS Gustavo L. C. MOURA SRD 6565 Willowick Pl.DaytonOHIO 45459-3005U.S.A. departamento de Quimica fundamental CCENUniversidade Federal de Pernambuco50590-470Recif ePEBrazil

The title complexes were modeled using the semiempirical MOPAC and the newly developed SPARKLe paramerters of the lanthanides. The calculated bond dis tances and angles agreed well with those found from crystal structure measuremen ts. This technique allows us to screen a large number of molecules and get struc tural information within a very short time.

关键词： lanthanide complex theoretical models octacoordination dipyridyl p henanthroline MOPAC SPARKLe rare earths

everything you always wanted to know about SDPD~★(~★but were afraid to ask)

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Applied Mathematics and Mechanics(english edition) 2018年第1期39卷 103-124页

作者： M. eLLeRO P. eSPANOL Zienkiewicz Centre for Computational engineering Swansea University SA1 8EN United Kingdom departamento de fisica fundamental Universidad Nacional de Educacion a Distancia Apartado 60141 E-28080 Madrid Spain

An overview of the smoothed dissipative particle dynamics （SDPD） method is presented in a format that tries to quickly answer questions that often arise among users and newcomers. It is hoped that the status of SDPD is clarified as a mesoscopic particle model and its potentials and limitations are highlighted, as compared with other methods.

关键词： mesoscopic particle method dissipative particle dynamics (DPD) smoothedparticle hydrodynamics (SPH) complex fluid

fundamental Gaps in Numerical Semigroups with Respect to Their Multiplicity

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Acta Mathematicae Applicatae Sinica 2004年第4期 629-646页

作者： J.C.ROSALeS P.A.GARCíA-SNCHeZ J.I.GARCíA-GARCíA J.A.JIMNeZ MADRID departamento de lgebra Universidad de Granada e-18071 Granada Spain departamento de lgebra Universidad de Granada e-18071 Granada Spain departamento de lgebra Universidad de Granada e-18071 Granada Spain Instituto de Astrofísica de Andalucía (CSIC) Apartado Postal 3004 18080 Granada Spain

for a numerical semigroup, we introduce the concept of a fundamental gap with respect tothe multiplicity of the *** semigroup is fully determined by its multiplicity and these *** study the case when a set of non-negative integers is the set of fundamental gaps with respect to themultiplicity of a numerical *** semigroups with maximum and mininmm number ofthis kind of gaps are described.

关键词： Numerical semigroup Gap Multiplicity frobenius number