Analysis of the 1S and 2S states of Λ_(Q) and Ξ_(Q) with QCD sum rules

In this article,we study the ground states and the first radial excited states of the flavor antitriplet heavy baryon states ∧Q and ΞQ with the spin-parity JP=1/2+ by carrying out operator product expansion up to vacuum condensates of dimension 10 in a consistent way.We observe for the first time that the higher dimensional vacuum condensates play an important role,and obtain very stable QCD sum rules with variations of the Borel parameters for the heavy baryon states.The predicted masses 6.08±0.09 GeV,2.78±0.08 GeV,and 2.96±0.09 GeV for the first radial excited states ∧b(2 S),∧c(2 S),and Ξc(2 S),respectively,are in excellent agreement with the experimental data and support assigning ∧b(6072),∧c(2765),and Ξc(2980/2970) to be the first radial excited states of ∧b,∧c,and Ξc,respectively.The predicted mass 6.24±0.07 GeV for Ξb(2 S) can be confirmed using experimental data in the future.