NLO effects for Ω_QQQbaryons in QCD Sum Rules *

Abstract

We study the triply heavy baryons in the QCD sum rules by performing the first calculation of the next-to-leading order (NLO) contribution to the perturbative QCD part of the correlation functions. Compared with the leading order (LO) result, the NLO contribution is found to be very important to the . This is because the NLO not only results in a large correction but also reduces the parameter dependence, making the Borel platform more distinct, especially for the in the scheme, where the platform appears only at NLO but not at LO. Particularly, owing to the inclusion of the NLO contribution, the renormalization schemes ( and On-Shell) dependence and the scale dependence are significantly reduced. Consequently, after including the NLO contribution to the perturbative part in the QCD sum rules, the masses are estimated to be GeV for and GeV for , where the results are obtained at with errors including those from the variation of the renormalization scale μ in the range . A careful study of the μ dependence in a wider range is further performed, which shows that the LO results are very sensitive to the choice of μ whereas the NLO results are considerably better. In addition to the result, a more stable value, (4.75-4.80) GeV, for the mass is found in the range of , which should be viewed as a more relevant prediction in our NLO approach because of dependence.

How to Reduce Char Formation in the Lignin Degradation Process: A Review

“…The char formed by intermediates and lignin in the depolymerization process has heat resistance and stability, and is difficult to degrade once formed. [28] Some research uses the char that forms during pyrolysis of lignin as an insulating material, [32][33] and these studies have demonstrated the high stability of char. However, researchers in lignin degradation prefer to minimize char formation in order to maximize the yield of valuable products from lignin (bio-oils, aromatic molecules).…”

“…[27] However, the harsh environment leads to cross-linking reactions between lignin molecules and depolymerization intermediates, which leads to the formation of stable solid char with a high molecular weight. [28] Because there exist many carbon-oxygen bonds (β-o-4) and carbon-carbon bonds (β-β, β-1) that link lignin monomers in rigid lignin macromolecules, which makes the degradation of these molecules require very high energy. Alternatively, the activation energy required to break these bonds is very high.…”

AMFlow: a Mathematica package for Feynman integrals computation via Auxiliary Mass Flow

“…AMF method has already been used to study many physical processes [62,63,64,65,66,67,68,69]. Especially, equipped with the iterative strategy [57], this method becomes extremely powerful so that many Feynman integrals in cutting-edge problems, which are very challenging for other meth-ods, can be calculated (see Fig.…”

Automatic computation of Feynman integrals containing linear propagators via auxiliary mass flow

“…[59]). At the same time, the AMF method has already been used in many physical processes [61][62][63][64][65][66][67][68].…”