472 research outputs found
Zb tetraquark channel and BB¯? interaction
No full text37th International Symposium on Lattice Field Theory, LATTICE 2019 -- 16 June 2019 through 22 June 2019 -- Wuhan -- 166411Two tetraquark candidates Zb(10610) and Zb(10650) with flavor structure bb ¯ du ¯ were discovered by Belle experiment in 2011. We present a preliminary Nf = 2 lattice study of the bb ¯ du ¯ system in the approximation of static b quarks, where the total spin of heavy quarks is fixed to one. The ground and the excited eigen-energies are determined as a function of separation r between b and b¯. The lower eigenstates are related to a bottomonium and a pion. One of the higher eigenstates is dominated by BB¯?: its energy is significantly below mB + mB? for r=[0.1,0.4] fm, which suggests sizable attraction. The attractive potential V(r) between B and B¯? is extracted assuming that this eigenstate is related exclusively to BB¯?. Assuming a certain form of the potential at small r < 0.1 fm and solving non-relativistic Schrodinger equation, we find a virtual bound state pole 32?+295 MeV below BB¯? threshold. This pole leads to a narrow peak in the cross-section just above threshold that could be perhaps related to experimental Zb resonances. Given all these approximations, we surprisingly find also a deep bound state 403 ±70 MeV below BB¯? threshold. If such a Zb state exists, it could be experimentally searched in the accurate dependence of rates on ?(1S)?+ invariant mass. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0).Research Agency ARRS, (J1-8137, P1-0035); TUBITAK; Deutsche Forschungsgemeinschaft, DFG; Türkiye Bilimsel ve Teknolojik Araştirma Kurumu, TÜBITA
Extension of Bertrand's theorem and factorization of the radial Schrodinger equation
No full textThe Bertrand's theorem is extended, i.e., closed orbits still may exist for central potentials other than the power law Coulomb potential and isotropic harmonic oscillator. It is shown that for the combined potential V(r) = W(r) + b/r(2) (W(r) = ar(nu)), when (and only when) W(r) is the Coulomb potential or isotropic harmonic oscillator, closed orbits still exist for suitable angular momentum. The correspondence between the closeness of classical orbits and the existence of raising and lowering operators derived from the factorization of the radial Schrodinger equation is investigated. (C) 1998 American Institute of Physics. [S0022-2488(98)00110-8].http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000076187800011&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Physics, MathematicalSCI(E)7ARTICLE105253-52593
Card-image public access catalogues (CIPACs) : Issues concerned with their planning and implementation
No full textThis article identifies and discusses the issues and problems that need to be considered in the process of planning and implementing card-image public access catalogues (CIPACs). CIPACs are online library catalogues based on databases of digitised catalogue cards with more or less sophisticated mechanisms for browsing or searching. Solutions of this kind have been implemented by a number of libraries in various countries since the mid-1990s, mainly as inexpensive alternatives to full retrospective conversion of their old catalogues. Based upon a questionnaire and relevant literature, the article looks at the following aspects: cost, conversion speed, universal access, saving of space, preservational aspects, software selection, preparing the card catalogue for conversion, scanning and quality control, image standards, optical character recognition, manual and intellectual input, technological aspects, administrative tools, organisational aspects, peculiarities of old catalogues, presentation of CIPACs to the users, and life expectancy of card-image catalogues
Carrier Dynamics and Quantum Confinement in type II ZB-WZ InP Nanowire Homostructures
No full textWe use time-resolved photoluminescence from single InP nanowires containing both wurtzite (WZ) and zincblende (ZB) crystalline phases to measure the carrier dynamics of quantum confined excitons in a type-ll homostructure. The observed recombination lifetime increases by nearly 2 orders of magnitude from 170 ps for excitons above the conduction and valence band barriers to more than 8400 ps for electrons and holes that are strongly confined in quantum wells defined by monolayer-scale ZB sections in a predominantly WZ nanowire. A simple computational model, guided by detailed high-resolution transmission electron microscopy measurements from a single nanowire, demonstrates that the dynamics are consistent with the calculated distribution of confined states for the electrons and holes
Cellular and molecular mechanisms of immuno-modulation by Ganoderma lucidum
No full textGanoderma lucidum (Leyss. ex Fr.) Karst. (Lingzhi or Reishi) has been used for a long time in China to prevent and treat various human diseases. G. lucidum polysaccharides extracted from G. lucidum are one of efficacious ingredient groups of G. lucidum. A number of reports have demonstrated that G. lucidum polysaccharides modulate immune function both in vivo and in vitro. The immuno-modulating effects of G. lucidum polysaccharides were extensive, including promoting the function of antigen-presenting cells, mononuclear phygocyte system, humoral immunity, and cellular immunity. Cellular and molecular mechanisms, possible receptors involved, and triggered signaling cascades have also been studied in vitro. However, whole animal experiments are still needed to further establish the mechanism of the immunomodulating effects by G. lucidum. Evidence-based clinical trials are also needed.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000232842900003&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Pharmacology & PharmacySCI(E)PubMed87REVIEW2144-1539
Adiectis passim im margine Responsorum ac Constitutionum capitibus, ex quibus Author suam Epitomen compilauit ...
No full textA Bernardo à Rey, I. V. D. fideliter reddita, ac in Latinam linguam conuersa ; Adiectis passim im margine Responsorum ac Constitutionum capitibus, ex quibus Author suam Epitomen compilauit ...DruckermarkeImpressum im Kolophon: Lvgdvni, Excudebat Ioannes Pvllon, Alias De Trin, Impensis honesti uiri Pauli MirallietiAus dem Vorbesitz des Klosters Rheinau Exemplar der ZB Züric
Dynamical symmetry of screened Coulomb potential and isotropic harmonic oscillator
No full textIt is shown that for the screened Coulomb potential and isotropic harmonic oscillator, there exists an infinite number of closed orbits for suitable angular momentum values. At the aphelion (perihelion) points of classical orbits, an extended Runge-Lenz vector for the screened Coulomb potential and an extended quadrupole tensor for the screened isotropic harmonic oscillator are still conserved. For the screened two-dimensional (2D) Coulomb potential and isotropic harmonic oscillator, the dynamical symmetries SO3 and SU(2) are still preserved at the aphelion (perihelion) points of classical orbits, respectively. For the screened 3D Coulomb potential, the dynamical symmetry SO4 is also preserved at the aphelion (perihelion) points of classical orbits. But for the screened 3D isotropic harmonic oscillator, the dynamical symmetry SU(2) is only preserved at the aphelion (perihelion) points of classical orbits in the eigencoordinate system. For the screened Coulomb potential and isotropic harmonic oscillator, only the energy (but not angular momentum) raising and lowering operators can be constructed from a factorization of the radial Schrodinger equation.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000089255400036&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701OpticsPhysics, Atomic, Molecular & ChemicalSCI(E)EI7ARTICLE3null6
Astronomical Tables And Precepts, For calculating the true Times of New and Full Moons, And shewing the method of projecting Eclipses From The Creation of the World to A.D. 7800 : To which is prefixed, A Short Theory Of The Solar and Lunar Motions
No full textBy James FergusonAus dem Vorbesitz der Naturforschenden Gesellschaft in Zürich Exemplar der ZB Züric
Topological analysis of the EBL model for the chaotic NMR laser
No full textBy determining relative rotation rates of the extended Bloch-type model, a consistent topological description for the model and the chaotic NMR laser at the parameter regime investigated is indicated. A geometrical method for calculating relative rotation rates, which is different from that of constructing the template, is proposed by establishing a symbolic plane in terms of the ordering of forward, and backward sequences encoding unstable periodic orbits.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000076017200011&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Physics, MultidisciplinarySCI(E)1ARTICLE2225-2302
Magnetic dipole moment of Z(b)(10610) in light-cone QCD
No full textAzizi, Kazem (Dogus Author) -- Özdem, Ulaş (Dogus Author)The magnetic dipole moment of the exotic Z(b)(10610) state is calculated within the light cone QCD sum rule method using the diquark-antidiquark and molecule interpolating currents. The magnetic dipole moment is obtained as mu(Zb) = 1.73 +/- 0.63 mu(N) in diquark-antidiquark picture and mu(Zb) = 1.59 +/- 0.58 mu(N) in the molecular case. The obtained results in both pictures together with the results of other theoretical studies on the spectroscopic parameters of the Zb(10610) state may be useful in determination of the nature and quark organization of this state
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