Year: 2026
Type: article
Abstract: We calculate the decay constants of the lowest-lying $$B_c$$ B c mesons in the spin-parity channels $$J^P {=}\,\, 0^-,\,0^+,\,1^-,\,1^+$$ J P = 0 - , 0 + , 1 - , 1 + , commonly referred to as the $$B_c,\, B_{c0}^*,\, B_c^*,\, B_{c1}$$ B c , B c 0 ∗ , B c ∗ , B c 1 mesons, respectively. Within the framework of QCD sum rules, we consider the decay constants associated with both the (axial-)vector and (axial-)tensor interpolating currents. The decay constants with (axial-)vector currents have already been studied in the literature. We refine previous QCD sum rule results by including higher-order power corrections and performing a comprehensive uncertainty analysis. Furthermore, we provide the first determination of the (axial-)tensor decay constants of the $$B_c^*$$ B c ∗ and $$B_{c1}$$ B c 1 mesons. These new results will not only improve theoretical predictions for purely leptonic $$B_c$$ B c decays, but also strengthen unitarity constraints on $$b \rightarrow c$$ b → c form factors, thereby improving the precision of predictions for $$\bar{B} \rightarrow D^{(*)} \ell \bar{\nu }$$ B ¯ → D ( ∗ ) ℓ ν ¯ decays and the determination of $$|V_{cb}|$$ | V cb |
Source: The European Physical Journal C
Institution: University of Bonn
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W7165844958