Decay constants of the heavy-light mesons from the field correlator method

Abstract

Meson Green's functions and decay constants f Γ in different channels Γ are calculated using the Field Correlator Method. Both, spectrum and f Γ , appear to be expressed only through universal constants: the string tension σ, α s , and the pole quark masses. For the S-wave states the calculated masses agree with the experimental numbers within ±5 MeV. For the D and D s mesons the values of f P (1S) are equal to 210(10) and 260(10) MeV, respectively, and their ratio f Ds /f D =1.24(3) agrees with recent CLEO experiment. The values f P (1S) = 182, 216, 438 MeV are obtained for the B, B s , and B c mesons with the ratio f Bs /f B =1.19(2) and f D /f B =1.14(2). The decay constants f P (2S) for the first radial excitations as well as the decay constants f V (1S) in the vector channel are also calculated. The difference of about 20% between f Ds and f D , f Bs and f B directly follows from our analytical formulas.

Higher excitations of theDandDsmesons

“…[13,14], while in [19] (the second paper) these two resonances are considered as the same 1 3 D 1 state with J P ¼ 1 À . These new data are extremely important for the theory to better understand the q " Q dynamics and test predictions made in a large variety of models [15][16][17][18][19][20][21][22][23][24][25], some of which were made long ago [15,16]. For low-lying states, the theoretical predictions are mostly in agreement with experiment within 20-50 MeV accuracy, although the parameters used may be very different.…”

“…Such small FS splittings cannot be explained within the universal description of fine structure used in Refs. [15,16,18].…”

“…The quantum numbers and decay modes of the new resonances were intensely discussed in a large number of recent studies [7][8][9][10][11][12][13][14] and also before in [15][16][17][18][19][20][21][22][23][24][25]. For D Ã s1 ð2710Þ the quantum numbers J P ¼ 1 À were assigned [4,7], although the analysis in Ref.…”

Erratum: Hyperfine splittings in bottomonium and theBq(q=n,s,c)mesons [Phys. Rev. D81, 071502 (2010)]

“…The w.f. at the origin are sensitive to the values of Λ B (n f ) (in [30] only the case with n f = 3 was considered). However, if the same freezing value of the coupling constant is taken for n f = 3, 4, 5, then the differences between the w.f.…”

Measurements of branching fractions of leptonic and hadronic $ D_s^{+} $ meson decays and extraction of the $ D_s^{+} $ meson decay constant

“…The current world average is f exp Ds = (260.0 ± 5.4) MeV [2]. Within the SM, f Ds has been predicted using several methods [16][17][18][19][20][21][22][23] and most calculations give values lower than the f Ds measurement although within theoretical and experimental uncertainties. The largest discrepancy is with an unquenched LQCD calculation that yields f LQCD Ds = (248.0 ± 2.5) MeV [16].…”