Superconvergence sum rules for radiative decays of meson resonances

Abstract In this article, we analyze tensor-vector-pseudoscalar(TVP) type of vertices $$D_{2}^{*+}D^{+}\rho $$D2∗+D+ρ, $$D_{2}^{*0}D^{0}\rho $$D2∗0D0ρ, $$D_{2}^{*+}D^{+}\omega $$D2∗+D+ω, $$D_{2}^{*0}D^{0}\omega $$D2∗0D0ω, $$B_{2}^{*+}B^{+}\rho $$B2∗+B+ρ, $$B_{2}^{*0}B^{0}\rho $$B2∗0B0ρ, $$B_{2}^{*+}B^{+}\omega $$B2∗+B+ω, $$B_{2}^{*0}B^{0}\omega $$B2∗0B0ω, $$B_{s2}^{*}B_{s}\phi $$Bs2∗Bsϕ and $$D_{s2}^{*}D_{s}\phi $$Ds2∗Dsϕ in the frame work of three point QCD sum rules(QCDSR). According to these analysis, we calculate their strong form factors which are used to fit into analytical functions of $$Q^{2}$$Q2. Then, we obtain the strong coupling constants by extrapolating these strong form factors into deep time-like regions. As an application of this work, the coupling constants for radiative decays of these heavy tensor mesons are also calculated at the point of $$Q^{2}=0$$Q2=0. With these coupling constants, we finally obtain the radiative decay widths of these tensor mesons.

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Radiative decays of heavy-light mesons and the $$ {f}_{H,{H}^{\ast },{H}_1}^{(T)} $$ decay constants

Journal of High Energy Physics ◽

10.1007/jhep09(2021)023 ◽

2021 ◽

Vol 2021 (9) ◽

Author(s):

Ben Pullin ◽

Roman Zwicky

Keyword(s):

Sum Rules ◽

Form Factors ◽

Radiative Decays ◽

Matrix Elements ◽

Leading Order ◽

Sum Rule ◽

Decay Constants ◽

Leptonic Decays ◽

Shell Matrix ◽

First Time

Abstract The on-shell matrix elements, or couplings $$ {g}_{H{H}^{\ast}\left({H}_1\right)\upgamma} $$ g H H ∗ H 1 γ , describing the $$ B{(D)}_q^{\ast } $$ B D q ∗ → B(D)qγ and B1q → Bqγ (q = u, d, s) radiative decays, are determined from light-cone sum rules at next-to-leading order for the first time. Two different interpolating operators are used for the vector meson, providing additional robustness to our results. For the D*-meson, where some rates are experimentally known, agreement is found. The couplings are of additional interest as they govern the lowest pole residue in the B(D) → γ form factors which in turn are connected to QED-corrections in leptonic decays B(D) → ℓ$$ \overline{\nu} $$ ν ¯ . Since the couplings and residues are related by the decay constants $$ {f}_{H^{\ast}\left({H}_1\right)} $$ f H ∗ H 1 and $$ {f}_{H^{\ast}\left({H}_1\right)}^T $$ f H ∗ H 1 T , we determine them at next-leading order as a by-product. The quantities $$ \left\{{f}_{H^{\ast}}^T,{f}_{H_1}^T\right\} $$ f H ∗ T f H 1 T have not previously been subjected to a QCD sum rule determination. All results are compared with the existing experimental and theoretical literature.

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