[PDF] Top 20 The flavour singlet mesons in QCD

... the singlet n ¯ n state would have a mass degenerate with the non-singlet n ¯ n if there were no disconnected contribu- ...the singlet s ¯s state would have if there were no disconnected ...flavor ... See full document

... Flavour singlet mesons can, in principle, be easily studied on a lattice. In prac- tice, lattice studies have been hampered by two constraints. One is that the disconnected quark diagrams needed for ... See full document

... the singlet and non-singlet mesons, as giving an indication of the strength and sign of OZI violating contri- butions to the heavy meson ...c mesons will not have these singlet ... See full document

... The spectrum of c¯ s mesons has been determined on four ensembles of gauge configura- tions. Three have different lattice spacings (a) and were generated in the quenched approxi- mation, which enables the ... See full document

... Figures 1 and 2 show that these statements are justified at the level of the correlation matrix and the overlaps respectively. In figure 1 we show the normalised correlation matrix at time-slice 5 for the T 1 + irrep in ... See full document

... Quantum Chromodynamics (QCD) describes strong interactions among quarks as processes in which colored gluons are exchanged. By virtue of their own color charge, gluons also strongly interact with quarks and among ... See full document

... Lattice gauge theory has also been applied to the b b ¯ meson spectrum. Since the b quark is three times as heavy as the c quark, it is more practical to use a nonrelativstic effective field theory called NRQCD. The most ... See full document

... ordinary mesons is identical (in that case dubbed as “flavour-preserving”) or not (in that case dubbed as “flavour-rearranging,” that is, has undergone some flavour reshu ffl ... See full document

... use QCD input and modelling to bridge this ...conceivable flavour combinations and fathom its implications for the predicted meson masses, decay constants, and in-meson condensates, by comparison with ... See full document

... D mesons arising in the fragmentation of c and b quarks provide a test of pQCD heavy flavour pro- duction, of heavy flavour content of the proton, and serve as an important constraint for heavy flavour backgrounds ... See full document

... We conclude with various remarks. First, we have demonstrated that it is possible to marry results from several techniques aside from perturbation theory to determine the structure of a renormalization group function at ... See full document

... e flavour l)ut arc degenerate, C -p arity is trivially generalised to a G'-parity-like ...same flavour and are non-degenerate, charge conjugation, or any generalisation of it, is no longer a sym m etry of ... See full document

... derive QCD sum rules from n-point Green functions of (appropriately defined) hadron interpolating ...any QCD sum rule found in the first step by naïve application of the formalism, and ...tetraquark ... See full document

... The problem of determining hadronic matrix elements in- volved in mixing—for example in mixing of glueball and scalar meson, in string breaking or in flavor-singlet meson studies—is much less straightforward. In ... See full document

... between flavour non-singlet and singlet mesons can be mea- sured using lattice evaluation of disconnected quark ...no flavour splitting of the masses, the mass splitting matrix element ... See full document

... pseudoscalar mesons led to the formulation of the “U(1) problem” ...of QCD, one would expect the ninth pseudoscalar meson to have a mass similar or a bit lighter than the kaons and the η me- ... See full document

... mainly the u and d quarkonium. Alfold and Jaffe analyzed the possibility that the σ is an exotic state i.e., tetraquark (qq ¯q ¯ q) by a quenched lattice QCD discarded the discon- nected diagram [12]. ... See full document

... Abstract. We report on the status of an ongoing effort by the RQCD and ALPHA Col- laborations, aimed at determining leptonic decay constants of charmed mesons. Our analysis is based on large-volume ensembles ... See full document

... Composite Higgs models based on the idea of walking technicolor require that the strongly in- teracting theory has near-conformal dynamics and these have been studied on the lattice in recent years [1, 2]. Interestingly, ... See full document

... The scalar strong interaction hadron theory [1,2] can ac- count, to a limited extent of varying accuracy, low en- ergy hadronic phenomena of basic importance. The high energy end has been left out. Quantum Chromodynamics ... See full document