CPviolation inBd,s→l+l−

Exclusive semileptonicBsdecays to excitedDsmesons: Search ofHuang1 2004Phys. Rev. D

“…In order to obtain information for ζ(y), ζ 1 (y) and η c,b ke (y) from the sum rules, we need the related decay constants, f −,1/2 and f +,1/2 , defined in (12) as input. The QCD sum rule calculations for the correlators of two heavy-light currents give [11,38]:…”

“…The continuum thresholds ω 0 and ω 1 in (28) and (29) are determined by requiring stability of these sum rules. One finds that 1.7 GeV < ω 0 < 2.2 GeV and 2.6 GeV < ω 1 < 3.1 GeV [11,33,38]. Imposing usual criterion on the ratio of contribution of the higher-order power corrections and that of the continuum, we find that for the central values of the condensates given in (30), if the threshold parameter ω c lies in the range 2.3 < ω c < 2.7 GeV, there is an acceptable "stability window" T = 0.8 − 1.2 GeV in which the calculation results do not change appreciably.…”

“…Based on the quark-antiquark picture, various theoretical models are modified to accommodate the low masses and the narrow widths for the new states [6,7,8,9,10]. QCD sum rule analysis in [11] supports the quark-antiquark postulation, both new states, D sJ (2317) and D sJ (2460), are identified to be thecs excited 0 + and 1 + states in the j l = 1 2 + doublet.…”

$$D^*_{s0}(2317)$$ D s 0 ∗ ( 2317 ) and $$\textit{DK}$$ DK scattering in B decays from BaBar and LHCb data

“…Because of its low mass, the structure of this meson has been extensively discussed. The suggested interpretations cover a wide range: cs state [11][12][13][14][15][16], two-meson molecular state [17][18][19][20][21][22][23][24][25][26][27], K -D mixing [28], four-quark states [29][30][31][32][33] or a mixture between two-meson and four-quark states [34].…”

The chiral transitions in heavy-light mesons

“…The masses of these states proved to be much lower than expected values in ordinary quark models while their widths were surprisingly small. The problem was studied in different approaches: in relativistic quark model calculations [2]- [4], on the lattice [5], in QCD Sum Rules [6,7], in chiral models [8,9] (for reviews see also [10,11]). Note, that the masses of D s (0 + ) and D s (1 + ) in closed-channel approximation typically exceed by ∼ 140 and 90 MeV their experimental numbers, so a multi-channel approach has to be applied to solve this problem.…”