Based on the flux tube model, the effects of the confining potentials of different configurations, namely the △-type and the Y-type, on the spectra of baryons are studied on SUSF（6） basis. The baryon spectra are ob...Based on the flux tube model, the effects of the confining potentials of different configurations, namely the △-type and the Y-type, on the spectra of baryons are studied on SUSF（6） basis. The baryon spectra are obtained in a unified manner. Our result shows that by employing either the △-mode or the Y-mode confining potential, one can achieve reasonable baryon spectra. The △-mode may be mostly effective for the short- and medium-distances, while the Y-mode may offer more contributions to the spectra for long-distances. Although the binding energies in baryon spectra may deviate by a few to several tens MeV for different modes, it is hard to determine either one to be dominant by simply evaluating the baryon spectra. One may need to invoke the baryon decay process to make further judgement.展开更多
In this work, we evaluate the lifetimes of the doubly charmed baryons Ξcc^＋ ,Ξcc^＋＋, and Ωcc^＋. We carefully calculate the non-spectator contributions at the quark level, where the Cabibbo-suppressed diagrams a...In this work, we evaluate the lifetimes of the doubly charmed baryons Ξcc^＋ ,Ξcc^＋＋, and Ωcc^＋. We carefully calculate the non-spectator contributions at the quark level, where the Cabibbo-suppressed diagrams are also included. The hadronic matrix elements are evaluated in the simple non-relativistic harmonic oscillator model. Our numerical results are generally consistent with that obtained by other authors who used the diquark model. However, all the theoretical predictions on the lifetimes are one order larger than the upper limit set by the recent SELEX measurement. This discrepancy would be clarified by the future experiment. If more accurate experiment still confirms the value of the SELEX collaboration, there must be some unknown mechanism to be explored.展开更多
We show how the Koide relationships and associated triplet mass matrices can be generalized to derive the observed sum of the free neutron and proton rest masses in terms of the up and down current quark masses and th...We show how the Koide relationships and associated triplet mass matrices can be generalized to derive the observed sum of the free neutron and proton rest masses in terms of the up and down current quark masses and the Fermi vev to six parts in 10,000. This sum can then be solved for the separate neutron and proton masses using the neutron minus proton mass difference derived by the author in a recent, separate paper. The oppositely-signed charges of the up and down quarks are responsible for the appearance of a complex phase exp(iδ) and real rotation angle θ which leads on an independent basis to mass and mixing matrices similar to that of Cabibbo, Kobayashi and Maskawa (CKM). These can then be used to specify the neutron and proton mass relationships to unlimited accuracy using θ as a nucleon fitting angle deduced from empirical data. This fitting angle is then shown to be related to an invariant of the CKM mixing angles within experimental errors. Also developed is a master mass and mixing matrix which may help to interconnect all baryon and quark masses and mixing angles. The Koide generalizations developed here enable these neutron and proton mass relationships to be given a Lagrangian formulation based on neutron and proton field strength tensors that contain vacuum-amplified and current quark wavefunctions and masses. In the course of development, we also uncover new Koide relationships for the neutrinos, the up quarks, and the down quarks.展开更多
Based on the thesis that baryons including protons and neutrons are Yang-Mills magnetic monopoles which the author has previously developed and which has been confirmed by over half a dozen empirically-accurate predic...Based on the thesis that baryons including protons and neutrons are Yang-Mills magnetic monopoles which the author has previously developed and which has been confirmed by over half a dozen empirically-accurate predictions, we develop a GUT that is rooted in the SU(4) subgroups for the proton/electron and neutron/neutrino which were used as the basis for these predictions. The SU(8) GUT group so-developed leads following three stages of symmetry breaking to all known phenomenology including a neutrino that behaves differently from other fermions, lepto-quark separation, replication of fermions into exactly three generations, the Cabibbo mixing of those generations, weak interactions which are left-chiral, and all four of the gravitational, strong, weak, and electromagnetic interactions. The next steps based on this development will be to calculate the masses and energies associated with the vacuum terms of the Lagrangian, to see if additional empirical confirmations can be achieved, especially for the proton and neutron and the fermion masses.展开更多
The exact solution of Sehrodinger equation corresponding to a baryonic system is the main interest in the present work. We take into account both quadratic and Coulomb terms in the potential relation. Next, after pres...The exact solution of Sehrodinger equation corresponding to a baryonic system is the main interest in the present work. We take into account both quadratic and Coulomb terms in the potential relation. Next, after presenting an exact solution, we have calculated the spin and isospin effects in both ground and excited states. The results are comparable with experimental data.展开更多
We study the masses of the doubly bottom baryons and the charmed-bottom baryons up to O(p^(3))in heavy baryon chiral perturbation theory.We determine the unknown low energy constants in the quark model and lattice QCD...We study the masses of the doubly bottom baryons and the charmed-bottom baryons up to O(p^(3))in heavy baryon chiral perturbation theory.We determine the unknown low energy constants in the quark model and lattice QCD.We show the numerical results for the masses of the doubly bottom baryons and the charmed-bottom baryons up to O(p^(3)).展开更多
The following article has been retracted due to the investigation of complaints received against it. Mr. Mohammadali Ghorbani (corresponding author and also the last author) cheated the authors’ name: Alireza Heidari...The following article has been retracted due to the investigation of complaints received against it. Mr. Mohammadali Ghorbani (corresponding author and also the last author) cheated the authors’ name: Alireza Heidari and Seyedali Vedad. The scientific community takes a very strong view on this matter and we treat all unethical behavior such as plagiarism seriously. This paper published in Vol.3 No.6 492-495, 2012, has been removed from this site.展开更多
The rigorous calculation of the spin-orbit terms in a three-quark system is realized based on the Gaussian expansion method and the infinitesimally-shifted Gaussian basis functions in the framework of the relativized ...The rigorous calculation of the spin-orbit terms in a three-quark system is realized based on the Gaussian expansion method and the infinitesimally-shifted Gaussian basis functions in the framework of the relativized quark model,by ignoring the mixing between different excited states.Then,the complete mass spectra of the singly heavy baryons are obtained rigorously,under the heavy-quark dominance mechanism.Accordingly,systematical analyses are performed for the reliability and predictive power of the model,the fine structure of the singly heavy baryon spectra,the assignments of the excited baryons,and some important topics about heavy baryon spectroscopy,such as the missing states,"spin-orbit puzzle,"and clustering effect.The results confirm that,under the heavy-quark dominance mechanism,the relativized quark model can describe the excitation spectra and the fine structures of the singly heavy baryons correctly and precisely.展开更多
In this study,we discuss the description of neutral Σ baryons with I(J^(P))=1(1/2^(+))and I(J^(P))=1(3/2^(+))using two bottom-up approaches:the deformed background and static dilaton models.In both models,we consider...In this study,we discuss the description of neutral Σ baryons with I(J^(P))=1(1/2^(+))and I(J^(P))=1(3/2^(+))using two bottom-up approaches:the deformed background and static dilaton models.In both models,we consider a non-linear Regge trajectory extension motivated by the strange nature of Σ baryons.We find that both models describe these systems with an RMS error smaller than 10%.We also perform a configurational entropy calculation in both models to discuss hadronic stability.展开更多
In this study,we investigate the production of doubly charmed baryons from anti-bottom charmedmesons.Using the effective Lagrangian approach,we discuss triangle diagrams at the hadronic level to access thebranching ra...In this study,we investigate the production of doubly charmed baryons from anti-bottom charmedmesons.Using the effective Lagrangian approach,we discuss triangle diagrams at the hadronic level to access thebranching ratios of B_(c)→B(ccq)+B(c^(-)q^(-)q^(-)).Apparently,the specific process B_(c)→Ξ_(cc)^(+)Ξ′_(c^(-))^(0) occupies the largest possibilityon the order of 9.1×10^(-5).In addition,although the production of undiscovered Ω_(cc)^(+) is Cabibbo suppressed in B^(-)_(c)→Ω_(cc)^(+)Ξ_(c^(-))^(0),its branching ratio can still reach a level of 10^(-7).These results are expected to provide valuable supportfor future experiments.展开更多
We present the first calculation of the connected scalar matrix element and the momentum fraction of the charm quark within the 3/2^(+)and 3/2^(-)triply charmed baryons on lattice QCD. The results are based on overlap...We present the first calculation of the connected scalar matrix element and the momentum fraction of the charm quark within the 3/2^(+)and 3/2^(-)triply charmed baryons on lattice QCD. The results are based on overlap valence fermions on two ensembles of N_(f)= 2 + 1 domain wall fermion configurations with two lattice spacings. The corresponding sea quark pion masses are 300 MeV and 278 MeV. The separated contributions to the triply charmed baryon mass are derived through the decomposition of the QCD energy-momentum tensor. The contribution of the connected charm quark matrix element to the triply charmed baryon is about 3/2 times that of the charmonium, and it is almost 70% of the total mass. The mass splitting of 3/2^(+)and 3/2^(-)triply charmed baryons is mainly from the 〈H_(E)〉 of the QCD energy-momentum tensor. A mass decomposition based on the quark model is also studied for comparison.展开更多
By using the ^(3)P_(0) pair creation model,we provide a detailed derivation of the transition matrix for a baryon decaying into a meson-baryon system.This analysis was successfully conducted for a meson in[J.Segovia,D...By using the ^(3)P_(0) pair creation model,we provide a detailed derivation of the transition matrix for a baryon decaying into a meson-baryon system.This analysis was successfully conducted for a meson in[J.Segovia,D.R.Entem,and F.Fernandez,Phys.Lett.B 715,322(2012),and we extend the same formalism to the baryon sector,focusing on the △(1232)→πN strong decay width because all hadrons involved in the reaction are very well established,the two hadrons in the final state are stable and require no further analysis,all quarks are light and thus equivalent,and the decay width of the process is relatively well measured.Utilizing a very common Rayleigh-Ritz variational method to solve the 2-and 3-body Schodinger bound-state equation in which the hadron's radial wave functions are expanded in terms of a Gaussian basis,we can relate the expression of the invariant matrix element with the mean-square radii of hadrons involved in the decay.We use their experimental measures in such a way that only the strength of the quark-antiquark pair creation from the vacuum is a free parameter.This is then taken from our previous study on strong decay widths in the meson sector[J.Segovia,D.R.Entem,and F.Fernandez,Phys.Lett.B 715,322(2012),and the obtained results are compatible with the experimental results for the calculated △(1232)→πN decay width.Despite requiring the calculation of additional baryon strong decays,a feasible avenue towards a unified description of both baryon and meson strong decay widths within a single constituent quark model framework may be attainable.Finally,this research has been developed to lay the foundation for a novel raft of applications to exotic hadrons,i.e.,the description of the baryon's coupling to meson-baryon thresholds,one of the mechanisms that is considered to be responsible for providing either a large renormalization to naive states or genuine dynamicallygenerated meson-baryon molecules.展开更多
The similar densities of dark matter and baryons in the universe imply that they may arise from the same ultraviolet model.B-Mesogenesis,which assumes dark matter is charged under the baryon number,attempts to simulta...The similar densities of dark matter and baryons in the universe imply that they may arise from the same ultraviolet model.B-Mesogenesis,which assumes dark matter is charged under the baryon number,attempts to simultaneously explain the origin of baryon asymmetry and dark matter in the universe.In particular,B-Mesogenesis may induce bottom-baryon decays into invisible or semi-invisible final states,which provide a distinctive signal for probing this scenario.In this work,we systematically study the invisible decays of bottom baryons into dark matter and the semi-invisible decays of bottom baryons into a meson or a photon together with a dark matter particle.In particular,the fully invisible decay can reveal the stable particles in B-Mesogenesis.Some QCD-based frameworks are used to calculate the hadronic matrix elements under the B-Mesogenesis model.We estimate the constraints on the Wilson coefficients or the product of some new physics couplings with the Wilson coefficients according to the semi-invisible and invisible decays of bottom baryons detectable at future colliders.展开更多
This is essentially an update of Ref. [1] [H. Y. Cheng, Int. J. Mod. Phys. A 24 （Suppl. 1）, 593 （2009）], a review of charmed baryon physics around 2007. Topics covered in this review include the spectroscopy, stro...This is essentially an update of Ref. [1] [H. Y. Cheng, Int. J. Mod. Phys. A 24 （Suppl. 1）, 593 （2009）], a review of charmed baryon physics around 2007. Topics covered in this review include the spectroscopy, strong decays, lifetimes, nonleptonic and semileptonic weak decays, and electromagnetic decays of charmed baryons.展开更多
Up to now, the excited charmed and bottom baryon states have still not been well studied experimentally or theoretically. In this paper, we predict the mass of Ωb, the only L=0 baryon state which has not been observe...Up to now, the excited charmed and bottom baryon states have still not been well studied experimentally or theoretically. In this paper, we predict the mass of Ωb, the only L=0 baryon state which has not been observed, to be 6069.2 MeV. The spectra of charmed and bottom baryons with the orbital angular momentum L= 1 are studied in two popular constituent quark models, the Goldstone boson exchange （GBE） model and the one gluon exchange （OGE） hyperfine interaction model. Inserting the latest experimental data from the ＂Review of Particle Physics＂, we find that in the GBE model, there exist some multiplets （∑c（b）, ≡c（b） and Ωc（b）） in which the total spin of the three quarks in their lowest energy states is 3/2, but in the OGE model there is no such phenomenon. This is the most important difference between the GBE and OGE models. These results can be tested in the near future. We suggest more efforts to study the excited charmed and bottom baryons both theoretically and experimentally, not only for the abundance of baryon spectra, but also for determining which hyperfine interaction model best describes nature.展开更多
The constituent quark model is used to compute the ground and excited state masses of QQQ baryons containing either c or b quarks.The quark model parameters previously used to describe the properties of charmonium and...The constituent quark model is used to compute the ground and excited state masses of QQQ baryons containing either c or b quarks.The quark model parameters previously used to describe the properties of charmonium and bottomonium states were used in this analysis.The 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 elements.Several low-lying states with quantum numbers J^P=1/2^±,3/2^±,5/2^±and 7/2^+are reported.We compare the results with those obtained by the other theoretical formalisms.There is a general agreement for the mass of the ground state in each sector of triply heavy baryons.However,the situation is more puzzling for the excited states,and appropriate comments about the most relevant features of our comparison are given.展开更多
Using the one-boson-exchange model,we studied the possible existence of very loosely bound hidden-charm molecular baryons composed of an anti-charmed meson and a charmed baryon.Our numerical results indicate that the ...Using the one-boson-exchange model,we studied the possible existence of very loosely bound hidden-charm molecular baryons composed of an anti-charmed meson and a charmed baryon.Our numerical results indicate that the Σ c ＊ and Σ c states exist,but that the Λ c and Λ c ＊ molecular states do not.展开更多
CHARMED BARYONS Revised March 2012 by C.G. Wohl （LBNL）. There are 17 known charmed baryons, and four other candidates not well enough established to be promoted to the Summary Tables.＊ Fig. l（a） shows the mass sp...CHARMED BARYONS Revised March 2012 by C.G. Wohl （LBNL）. There are 17 known charmed baryons, and four other candidates not well enough established to be promoted to the Summary Tables.＊ Fig. l（a） shows the mass spectrum,展开更多
基金The project supported by the Special Scientific Research Foundation for Doctoral Programs of Universities of China.
文摘Based on the flux tube model, the effects of the confining potentials of different configurations, namely the △-type and the Y-type, on the spectra of baryons are studied on SUSF（6） basis. The baryon spectra are obtained in a unified manner. Our result shows that by employing either the △-mode or the Y-mode confining potential, one can achieve reasonable baryon spectra. The △-mode may be mostly effective for the short- and medium-distances, while the Y-mode may offer more contributions to the spectra for long-distances. Although the binding energies in baryon spectra may deviate by a few to several tens MeV for different modes, it is hard to determine either one to be dominant by simply evaluating the baryon spectra. One may need to invoke the baryon decay process to make further judgement.
基金The project supported by National Natural Science Foundation of China
文摘In this work, we evaluate the lifetimes of the doubly charmed baryons Ξcc^＋ ,Ξcc^＋＋, and Ωcc^＋. We carefully calculate the non-spectator contributions at the quark level, where the Cabibbo-suppressed diagrams are also included. The hadronic matrix elements are evaluated in the simple non-relativistic harmonic oscillator model. Our numerical results are generally consistent with that obtained by other authors who used the diquark model. However, all the theoretical predictions on the lifetimes are one order larger than the upper limit set by the recent SELEX measurement. This discrepancy would be clarified by the future experiment. If more accurate experiment still confirms the value of the SELEX collaboration, there must be some unknown mechanism to be explored.
文摘We show how the Koide relationships and associated triplet mass matrices can be generalized to derive the observed sum of the free neutron and proton rest masses in terms of the up and down current quark masses and the Fermi vev to six parts in 10,000. This sum can then be solved for the separate neutron and proton masses using the neutron minus proton mass difference derived by the author in a recent, separate paper. The oppositely-signed charges of the up and down quarks are responsible for the appearance of a complex phase exp(iδ) and real rotation angle θ which leads on an independent basis to mass and mixing matrices similar to that of Cabibbo, Kobayashi and Maskawa (CKM). These can then be used to specify the neutron and proton mass relationships to unlimited accuracy using θ as a nucleon fitting angle deduced from empirical data. This fitting angle is then shown to be related to an invariant of the CKM mixing angles within experimental errors. Also developed is a master mass and mixing matrix which may help to interconnect all baryon and quark masses and mixing angles. The Koide generalizations developed here enable these neutron and proton mass relationships to be given a Lagrangian formulation based on neutron and proton field strength tensors that contain vacuum-amplified and current quark wavefunctions and masses. In the course of development, we also uncover new Koide relationships for the neutrinos, the up quarks, and the down quarks.
文摘Based on the thesis that baryons including protons and neutrons are Yang-Mills magnetic monopoles which the author has previously developed and which has been confirmed by over half a dozen empirically-accurate predictions, we develop a GUT that is rooted in the SU(4) subgroups for the proton/electron and neutron/neutrino which were used as the basis for these predictions. The SU(8) GUT group so-developed leads following three stages of symmetry breaking to all known phenomenology including a neutrino that behaves differently from other fermions, lepto-quark separation, replication of fermions into exactly three generations, the Cabibbo mixing of those generations, weak interactions which are left-chiral, and all four of the gravitational, strong, weak, and electromagnetic interactions. The next steps based on this development will be to calculate the masses and energies associated with the vacuum terms of the Lagrangian, to see if additional empirical confirmations can be achieved, especially for the proton and neutron and the fermion masses.
文摘The exact solution of Sehrodinger equation corresponding to a baryonic system is the main interest in the present work. We take into account both quadratic and Coulomb terms in the potential relation. Next, after presenting an exact solution, we have calculated the spin and isospin effects in both ground and excited states. The results are comparable with experimental data.
基金supported by the National Natural Science Foundation of China under Grants No.11905171 and No 12047502supported by the Natural Science Basic Research Plan in Shaanxi Province of China under Grant No.2022JQ-025。
文摘We study the masses of the doubly bottom baryons and the charmed-bottom baryons up to O(p^(3))in heavy baryon chiral perturbation theory.We determine the unknown low energy constants in the quark model and lattice QCD.We show the numerical results for the masses of the doubly bottom baryons and the charmed-bottom baryons up to O(p^(3)).
文摘The following article has been retracted due to the investigation of complaints received against it. Mr. Mohammadali Ghorbani (corresponding author and also the last author) cheated the authors’ name: Alireza Heidari and Seyedali Vedad. The scientific community takes a very strong view on this matter and we treat all unethical behavior such as plagiarism seriously. This paper published in Vol.3 No.6 492-495, 2012, has been removed from this site.
基金Supported by the Open Project of Guangxi Key Lab of Nuclear Physics and Technology(NLK2023-04)the Central Government Guidance Funds for Local Scientific and Technological Development in China(Guike ZY22096024)+3 种基金the Natural Science Foundation of Guizhou Province-ZK[2024](General Project)650the National Natural Science Foundation of China(11675265,12175068)the Continuous Basic Scientific Research Project(WDJC-2019-13)the Leading Innovation Project(LC 192209000701)。
文摘The rigorous calculation of the spin-orbit terms in a three-quark system is realized based on the Gaussian expansion method and the infinitesimally-shifted Gaussian basis functions in the framework of the relativized quark model,by ignoring the mixing between different excited states.Then,the complete mass spectra of the singly heavy baryons are obtained rigorously,under the heavy-quark dominance mechanism.Accordingly,systematical analyses are performed for the reliability and predictive power of the model,the fine structure of the singly heavy baryon spectra,the assignments of the excited baryons,and some important topics about heavy baryon spectroscopy,such as the missing states,"spin-orbit puzzle,"and clustering effect.The results confirm that,under the heavy-quark dominance mechanism,the relativized quark model can describe the excitation spectra and the fine structures of the singly heavy baryons correctly and precisely.
基金supported by the National Natural Science Foundation of China(12350410371)supported by the Research Foundation of Education Bureau of Hunan Province,China(21B0402)the Natural Science Foundation of Hunan Province,China(2022JJ40344)。
文摘In this study,we discuss the description of neutral Σ baryons with I(J^(P))=1(1/2^(+))and I(J^(P))=1(3/2^(+))using two bottom-up approaches:the deformed background and static dilaton models.In both models,we consider a non-linear Regge trajectory extension motivated by the strange nature of Σ baryons.We find that both models describe these systems with an RMS error smaller than 10%.We also perform a configurational entropy calculation in both models to discuss hadronic stability.
基金support by National Natural Science Foundation of China(12005294)the Fundamental Funds for Key disciplines in Physics(2022WLXK05)supported by National Natural Science Foundation of China(12105247)。
文摘In this study,we investigate the production of doubly charmed baryons from anti-bottom charmedmesons.Using the effective Lagrangian approach,we discuss triangle diagrams at the hadronic level to access thebranching ratios of B_(c)→B(ccq)+B(c^(-)q^(-)q^(-)).Apparently,the specific process B_(c)→Ξ_(cc)^(+)Ξ′_(c^(-))^(0) occupies the largest possibilityon the order of 9.1×10^(-5).In addition,although the production of undiscovered Ω_(cc)^(+) is Cabibbo suppressed in B^(-)_(c)→Ω_(cc)^(+)Ξ_(c^(-))^(0),its branching ratio can still reach a level of 10^(-7).These results are expected to provide valuable supportfor future experiments.
基金Supported by the National Natural Science Foundation of China (12175036, 11935017, 12175073, 12205311, 12222503)the Natural Science Foundation of Hunan Province,China (2023JJ30380, 2024JJ6300)+1 种基金the Department of Education Foundation of Hunan Province,China (20A310, 22B0044)the Major Project of Basic and Applied Basic Research of Guangdong Province,China (2020B0301030008)。
文摘We present the first calculation of the connected scalar matrix element and the momentum fraction of the charm quark within the 3/2^(+)and 3/2^(-)triply charmed baryons on lattice QCD. The results are based on overlap valence fermions on two ensembles of N_(f)= 2 + 1 domain wall fermion configurations with two lattice spacings. The corresponding sea quark pion masses are 300 MeV and 278 MeV. The separated contributions to the triply charmed baryon mass are derived through the decomposition of the QCD energy-momentum tensor. The contribution of the connected charm quark matrix element to the triply charmed baryon is about 3/2 times that of the charmonium, and it is almost 70% of the total mass. The mass splitting of 3/2^(+)and 3/2^(-)triply charmed baryons is mainly from the 〈H_(E)〉 of the QCD energy-momentum tensor. A mass decomposition based on the quark model is also studied for comparison.
基金Work partially financed by the Escuela Politécnica Nacional under projects PIS-22-04 and PIM 19-01EU Horizon 2020 research and innovation program,STRONG-2020 project,under grant no.824093+1 种基金Ministerio Español de Ciencia e Innovación under grant nos.PID2022-141910NB-I00 and PID2022-140440NB-C22Junta de Andalucía under contract no.PAIDI FQM-370。
文摘By using the ^(3)P_(0) pair creation model,we provide a detailed derivation of the transition matrix for a baryon decaying into a meson-baryon system.This analysis was successfully conducted for a meson in[J.Segovia,D.R.Entem,and F.Fernandez,Phys.Lett.B 715,322(2012),and we extend the same formalism to the baryon sector,focusing on the △(1232)→πN strong decay width because all hadrons involved in the reaction are very well established,the two hadrons in the final state are stable and require no further analysis,all quarks are light and thus equivalent,and the decay width of the process is relatively well measured.Utilizing a very common Rayleigh-Ritz variational method to solve the 2-and 3-body Schodinger bound-state equation in which the hadron's radial wave functions are expanded in terms of a Gaussian basis,we can relate the expression of the invariant matrix element with the mean-square radii of hadrons involved in the decay.We use their experimental measures in such a way that only the strength of the quark-antiquark pair creation from the vacuum is a free parameter.This is then taken from our previous study on strong decay widths in the meson sector[J.Segovia,D.R.Entem,and F.Fernandez,Phys.Lett.B 715,322(2012),and the obtained results are compatible with the experimental results for the calculated △(1232)→πN decay width.Despite requiring the calculation of additional baryon strong decays,a feasible avenue towards a unified description of both baryon and meson strong decay widths within a single constituent quark model framework may be attainable.Finally,this research has been developed to lay the foundation for a novel raft of applications to exotic hadrons,i.e.,the description of the baryon's coupling to meson-baryon thresholds,one of the mechanisms that is considered to be responsible for providing either a large renormalization to naive states or genuine dynamicallygenerated meson-baryon molecules.
基金Supported by the National Key Research and Development Program of China(2020YFA0406400,2023YFA1606000)the National Natural ScienceFoundationof China(12335003,12275277)。
文摘The similar densities of dark matter and baryons in the universe imply that they may arise from the same ultraviolet model.B-Mesogenesis,which assumes dark matter is charged under the baryon number,attempts to simultaneously explain the origin of baryon asymmetry and dark matter in the universe.In particular,B-Mesogenesis may induce bottom-baryon decays into invisible or semi-invisible final states,which provide a distinctive signal for probing this scenario.In this work,we systematically study the invisible decays of bottom baryons into dark matter and the semi-invisible decays of bottom baryons into a meson or a photon together with a dark matter particle.In particular,the fully invisible decay can reveal the stable particles in B-Mesogenesis.Some QCD-based frameworks are used to calculate the hadronic matrix elements under the B-Mesogenesis model.We estimate the constraints on the Wilson coefficients or the product of some new physics couplings with the Wilson coefficients according to the semi-invisible and invisible decays of bottom baryons detectable at future colliders.
文摘This is essentially an update of Ref. [1] [H. Y. Cheng, Int. J. Mod. Phys. A 24 （Suppl. 1）, 593 （2009）], a review of charmed baryon physics around 2007. Topics covered in this review include the spectroscopy, strong decays, lifetimes, nonleptonic and semileptonic weak decays, and electromagnetic decays of charmed baryons.
基金Supported by National Natural Science Foundation of China(11175020,11575023,U1204115)
文摘Up to now, the excited charmed and bottom baryon states have still not been well studied experimentally or theoretically. In this paper, we predict the mass of Ωb, the only L=0 baryon state which has not been observed, to be 6069.2 MeV. The spectra of charmed and bottom baryons with the orbital angular momentum L= 1 are studied in two popular constituent quark models, the Goldstone boson exchange （GBE） model and the one gluon exchange （OGE） hyperfine interaction model. Inserting the latest experimental data from the ＂Review of Particle Physics＂, we find that in the GBE model, there exist some multiplets （∑c（b）, ≡c（b） and Ωc（b）） in which the total spin of the three quarks in their lowest energy states is 3/2, but in the OGE model there is no such phenomenon. This is the most important difference between the GBE and OGE models. These results can be tested in the near future. We suggest more efforts to study the excited charmed and bottom baryons both theoretically and experimentally, not only for the abundance of baryon spectra, but also for determining which hyperfine interaction model best describes nature.
基金Supported by China Postdoctoral Science Foundation(2019M650617)National Natural Science Foundation of China(11535005,11775118)+2 种基金Spanish Ministerio de Economía,Industria y Competitividad under contracts no.FPA2017-86380-P and FPA2016-77177-C2-2-P.P.G.O.the financial support from Spanish MINECO’s Juan de la Cierva-Incorporación programmeGrant Agreement No.IJCI-2016-28525
文摘The constituent quark model is used to compute the ground and excited state masses of QQQ baryons containing either c or b quarks.The quark model parameters previously used to describe the properties of charmonium and bottomonium states were used in this analysis.The 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 elements.Several low-lying states with quantum numbers J^P=1/2^±,3/2^±,5/2^±and 7/2^+are reported.We compare the results with those obtained by the other theoretical formalisms.There is a general agreement for the mass of the ground state in each sector of triply heavy baryons.However,the situation is more puzzling for the excited states,and appropriate comments about the most relevant features of our comparison are given.
基金Supported by National Natural Science Foundation of China (11175073,11075004,11021092,11035006,11047606,10805048)Ministry of Science and Technology of China (2009CB825200)+1 种基金Ministry of Education of China (FANEDD 200924,DPFIHE20090211120029,NCET NCET-10-0442)Fundamental Research Funds for the Central Universities(lzujbky-2010-69)
文摘Using the one-boson-exchange model,we studied the possible existence of very loosely bound hidden-charm molecular baryons composed of an anti-charmed meson and a charmed baryon.Our numerical results indicate that the Σ c ＊ and Σ c states exist,but that the Λ c and Λ c ＊ molecular states do not.
文摘CHARMED BARYONS Revised March 2012 by C.G. Wohl （LBNL）. There are 17 known charmed baryons, and four other candidates not well enough established to be promoted to the Summary Tables.＊ Fig. l（a） shows the mass spectrum,
