Accurate Bottom-Quark Mass from Borel QCD Sum Rules for the Decay Constants of B and Bs Mesons

Abstract

The XXIst International Workshop High Energy Physics and Quantum Field Theory

B meson decay constants f B c $$ {f}_{B_c} $$ , f B s $$ {f}_{B_s} $$ and f B from QCD sum rules

“…To find this region of stability we begin by choosing a value of n = 3, 4, 5, .. and then increasing s 0 until stability is reached in each case. In order to make the duality region more pronounced we allow the value of the threshold s cont to vary around the physical threshold s phys , as in [28], and in such a way that the dependence of f Bq on s 0 shows maximum stability. This means requiring that the first and second derivatives vanish at the same point.…”