1993/10/19 by Stefan Herrlich, S. Herrlich, Ulrich Nierste +1 · 6 citations
Mathematics · Physics and Astronomy · #Hamiltonian (control theory) #High-Energy Particle Collisions Research #Logarithm #Mathematical analysis #Mathematical physics #Mathematics #Order (exchange) #Particle physics #Particle physics theoretical and experimental studies #Perturbative QCD #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Renormalization #Renormalization group #hep-ph
paper · pdf · doi:10.1016/0550-3213(94)90044-2
published as Nucl.Phys. B419 (1994) 292-322 · 30 pages and 9 figures (available as uuencoded tarred postscript files), LaTeX, TUM-T31-40/93
arxiv created 1993/10/19 · openalex publication_date 1994/05/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We calculate the next-to-leading order short distance QCD corrections to the coefficient η1 of the effective ΔS = 2 hamiltonian in the standard model. This part dominates the short distance contribution (ΔmK)\rm SD to the KL -- KS mass difference. The next-to-leading order result enhances η1 and (ΔmK)\rm SD by 20% compared to the leading order estimate. Taking 0.200 \gev ≤ \laMSb ≤ 0.350 \gev and 1.35 \gev ≤ mc(mc) ≤ 1.45 \gev we obtain 0.922 ≤ η1\rm NLO ≤ 1.419 compared to 0.834 ≤ η1\rm LO ≤ 1.138. For BK = 0.7 this corresponds to 48 -- 75 % of the experimentally observed mass difference. The inclusion of next-to- leading order corrections to η1 reduces considerably the theoretical uncertainty related to the choice of renormalization scales.