Deconlinement phase transition and neutrino trapping in （proto）neutron star matter are investigated in a chiral hadronic model （also referred to as the FST model） for the hadronic phase （HP） and in the color-fla...Deconlinement phase transition and neutrino trapping in （proto）neutron star matter are investigated in a chiral hadronic model （also referred to as the FST model） for the hadronic phase （HP） and in the color-flavor-locked （CFL） quark model for the deconlined quark phase. We include a perturbative QCD correction parameter αs in the CFL quark matter equation of states. It is shown that the CFL quark core with K^0 condensation forms in neutron star matter with the large value of αs. If the small value of αs is taken, hyperons suppress the CFL quark phase and the liP is dominant in the high-density region of （proto）neutron star matter. Neutrino trapping makes the fraction of the CFL quark matter decrease compared with those without neutrino trapping. Moreover, increasing the QCD correction parameter as or decreasing the bag constant B and the strange quark mass ms can make the fraction of the CFL quark matter increase, simultaneously, the fraction of neutrino in protoneutron star matter increases, too. The maximum masses and the corresponding radii of （proto）neutron stars are not sensitive to the QCD correction parameter αs.展开更多
Using proton-proton collision data at centre-of-mass energies of and 13 TeV recorded by the LHCb experiment at the Large Hadron Collider,corresponding to an integrated luminosity of 9 fb-1,the invariant mass spectrum ...Using proton-proton collision data at centre-of-mass energies of and 13 TeV recorded by the LHCb experiment at the Large Hadron Collider,corresponding to an integrated luminosity of 9 fb-1,the invariant mass spectrum of J/ψ pairs is studied.A narrow structure around 6:9 GeV=c^2 matching the lineshape of a resonance and a broad structure just above twice the J/ψ mass are observed.The deviation of the data from nonresonant J/ψ-pair production is above five standard deviations in the mass region between 6:2 and 7:4 GeV=c^2,covering predicted masses of states composed of four charm quarks.The mass and natural width of the narrow X(6900)structure are measured assuming a Breit-Wigner lineshape.展开更多
The behavior of graphene bombarded by fullerene(C60 and C70)and its derivatives through using nonequilibrium molecular dynamics method are studied.The microscopic mechanism of passing through graphene is obviously rel...The behavior of graphene bombarded by fullerene(C60 and C70)and its derivatives through using nonequilibrium molecular dynamics method are studied.The microscopic mechanism of passing through graphene is obviously related to the initial structure of destroying carbon-carbon bonds and the strong interaction between the circular region of graphene and the cluster.The probability of passing through graphene depends on the incident velocity of clusters,the species of clusters,the temperature of heat baths,and the defect of graphene.Our results can provide a perspective for further understanding the mechanism of generating nanopores in graphene.The clusters used here may also bring about some potential utilities in tie functionalization of graphene and the production of nanopores.展开更多
基金National Natural Science Foundation of China under Grant Nos.10575005,10435080,10425521,10135030,and 10575123the Key Grant Project of the Ministry of Education under Grant No.305001the CAS Knowledge Innovation Project under Grant No.KJcx2-sw-No2
文摘Deconlinement phase transition and neutrino trapping in （proto）neutron star matter are investigated in a chiral hadronic model （also referred to as the FST model） for the hadronic phase （HP） and in the color-flavor-locked （CFL） quark model for the deconlined quark phase. We include a perturbative QCD correction parameter αs in the CFL quark matter equation of states. It is shown that the CFL quark core with K^0 condensation forms in neutron star matter with the large value of αs. If the small value of αs is taken, hyperons suppress the CFL quark phase and the liP is dominant in the high-density region of （proto）neutron star matter. Neutrino trapping makes the fraction of the CFL quark matter decrease compared with those without neutrino trapping. Moreover, increasing the QCD correction parameter as or decreasing the bag constant B and the strange quark mass ms can make the fraction of the CFL quark matter increase, simultaneously, the fraction of neutrino in protoneutron star matter increases, too. The maximum masses and the corresponding radii of （proto）neutron stars are not sensitive to the QCD correction parameter αs.
基金support from CERNfrom the national agencies: CAPES, CNPq, FAPERJ and FINEP (Brazil)+20 种基金MOST and NSFC (China)CNRS/IN2P3 (France)BMBF, DFG and MPG (Germany)INFN (Italy)NWO (Netherlands)MNiSW and NCN (Poland)MEN/IFA (Romania)MSHE (Russia)MinECo (Spain)SNSF and SER (Switzerland)NASU (Ukraine)STFC (United Kingdom)DOE NP and NSF (USA)AvH Foundation (Germany)EPLANET, Marie Sklodowska-Curie Actions and ERC (European Union)A^(*)MIDEX, ANR, Labex P2IO and OCEVU, and Region Auvergne-Rhone-Alpes (France)Key Research Program of Frontier Sciences of CAS, CAS PIFIthe Thousand Talents Program (China)RFBR, RSF and Yandex LLC (Russia)GVA, XuntaGal and GENCAT (Spain)the Royal Society and the Leverhulme Trust (United Kingdom)。
文摘Using proton-proton collision data at centre-of-mass energies of and 13 TeV recorded by the LHCb experiment at the Large Hadron Collider,corresponding to an integrated luminosity of 9 fb-1,the invariant mass spectrum of J/ψ pairs is studied.A narrow structure around 6:9 GeV=c^2 matching the lineshape of a resonance and a broad structure just above twice the J/ψ mass are observed.The deviation of the data from nonresonant J/ψ-pair production is above five standard deviations in the mass region between 6:2 and 7:4 GeV=c^2,covering predicted masses of states composed of four charm quarks.The mass and natural width of the narrow X(6900)structure are measured assuming a Breit-Wigner lineshape.
基金Supported in part by the National Natural Science Foundation of China under Grant Nos.11004082,and 11291240477the Natural Science Foundation of Guangdong Province under Grant No.2014A030313367the Fundamental Research Funds for the Central Universities,Jinan University under Grant Nos.21611437 and 11614341
文摘The behavior of graphene bombarded by fullerene(C60 and C70)and its derivatives through using nonequilibrium molecular dynamics method are studied.The microscopic mechanism of passing through graphene is obviously related to the initial structure of destroying carbon-carbon bonds and the strong interaction between the circular region of graphene and the cluster.The probability of passing through graphene depends on the incident velocity of clusters,the species of clusters,the temperature of heat baths,and the defect of graphene.Our results can provide a perspective for further understanding the mechanism of generating nanopores in graphene.The clusters used here may also bring about some potential utilities in tie functionalization of graphene and the production of nanopores.
