Coupling constants of bottom (charmed) mesons with the pion from three-point QCD sum rules

Abstract

In this article, the three-point QCD sum rules are used to compute the strong coupling constants of vertices containing the strange bottomed (charmed) mesons with the pion. The coupling constants are calculated when both the bottom (charm) and the pion states are off-shell. A comparison of the obtained results of the coupling constants with existing predictions is also made.

Coupling constants calculation of charmed meson with kaon from QCD sum rules

“…The upper limits of the integrals in Eqs. (20), are the continuum thresholds. In each vertex , if we take the initial meson mass and the final meson mass as m and m ′ respectively, then the continuum thresholds are s 0 = (m + ∆) 2 and s ′ 0 = (m ′ + ∆ ′ ) 2 , and ∆(∆ ′ ) varies between 0.4 ≤ ∆(∆ ′ ) ≤ 1 [20].…”

“…(20), are the continuum thresholds. In each vertex , if we take the initial meson mass and the final meson mass as m and m ′ respectively, then the continuum thresholds are s 0 = (m + ∆) 2 and s ′ 0 = (m ′ + ∆ ′ ) 2 , and ∆(∆ ′ ) varies between 0.4 ≤ ∆(∆ ′ ) ≤ 1 [20]. By using ∆(∆ ′ ) = 0.5 and fixing Q 2 = 1 GeV , we plot the dependence of the strong coupling constant g K D * D * s K on the Borel parameters, M 2 1 and M 2 2 in Fig.…”

“…Determination of the strong coupling constants helps us to better understand, the nature of the strong interactions and hadronic phenomena that are described by the nonperturbative QCD approach. QCD sum rules(QCDSR) [1] are among the most interesting approaches at the low-energy region that have determined many successful calculations about the mesonic vertices such as D * Dπ [2, 3], DDρ [4], D * D * ρ [5], DDJ/ψ [6], D * DJ/ψ [7], D * D s K, D * s DK, D 0 D s K, D s0 DK [8], D * D * P , D * DV , DDV [9], D * D * π [10], D * D * J/ψ [11], D s D * K, D * s DK [12], DDω [13], φD * s0 D * s0 , φD s D s , φD * s D * s , φD s1 D s1 [14], B s0 BK [15], B * s BK [16], D * s D s φ [17] , D s DK * 0 , B s BK * 0 , D * s DK, B * s BK, D * s DK 1 , B * s BK 1 [18], K * Kπ, φKK, φK * K * , ρK * K * [19], B 1 B * π, B 1 B 0 π, B 1 B 1 π, D 1 D * π, D 1 D 0 π and D 1 D 1 π [20].…”

“…Determination of the strong coupling constants helps us to better understand, the nature of the strong interactions and hadronic phenomena that are described by the nonperturbative QCD approach. QCD sum rules(QCDSR) [1] are among the most interesting approaches at the low-energy region that have determined many successful calculations about the mesonic vertices such as D * Dπ [2,3], DDρ [4], D * D * ρ [5], DDJ/ψ [6], D * DJ/ψ [7], s DK [12], DDω [13], φD * s0 D * s0 , φD s D s , φD * s D * s , φD s1 D s1 [14], B s0 BK [15] [18], K * Kπ, φKK, φK * K * , ρK * K * [19], [20].…”

Charm meson couplings in hard-wall Holographic QCD

“…D * D π, D * D γ, D D ρ, D * D * ρ vertices are analyzed via lattice QCD approach in [12][13][14][15]. Moreover, D * D * ρ [16], D * Dπ [17,18], DDρ [19], D * Dρ [20], DDJ/ψ [21], D * DJ/ψ [22] s DK [26], DDω [27], D s D s V , D * s D * s V [28,29], D 1 D * π, D 1 D 0 π, D 1 D 1 π [30] and DDA, D * DA [31], vertices are often studied via the three point sum rule (3PSR) and the light cone QCD sum rule (LCSR) methods.…”