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Title: Neutral kaon mixing beyond the Standard Model with n f = 2 + 1 chiral fermions. Part 2: non perturbative renormalisation of the ΔF = 2 four-quark operators

We compute the renormalisation factors (Z-matrices) of the ΔF = 2 four-quark operators needed for Beyond the Standard Model (BSM) kaon mixing. We work with nf = 2+1 flavours of Domain-Wall fermions whose chiral-flavour properties are essential to maintain a continuum-like mixing pattern. We introduce new RI-SMOM renormalisation schemes, which we argue are better behaved compared to the commonly-used corresponding RI-MOM one. We find that, once converted to MS¯, the Z-factors computed through these RI-SMOM schemes are in good agreement but differ significantly from the ones computed through the RI-MOM scheme. The RI-SMOM Z-factors presented here have been used to compute the BSM neutral kaon mixing matrix elements in the companion paper. In conclusion, we argue that the renormalisation procedure is responsible for the discrepancies observed by different collaborations, we will investigate and elucidate the origin of these differences throughout this work.
 [1] ;  [2] ;  [3] ;  [4] ;  [5]
  1. Univ. of Edinburgh, Edinburgh (United Kingdom)
  2. Univ. of Liverpool, Liverpool (United Kingdom)
  3. York Univ., Toronto (Canada)
  4. Brookhaven National Lab. (BNL), Upton, NY (United States)
  5. Univ. of Glasgow, Glasgow (United Kingdom)
Publication Date:
Report Number(s):
Journal ID: ISSN 1029-8479; KA2401012; TRN: US1800726
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of High Energy Physics (Online)
Additional Journal Information:
Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2017; Journal Issue: 10; Journal ID: ISSN 1029-8479
Springer Berlin
Research Org:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Orgs:
The RBC/UKQCD collaboration
Country of Publication:
United States
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; z-matrice; quark; DM; particles; fermions; kaon; BSM; chiral; flavour; RI-SMOM; Lattice field theory simulation; Non-perturbative renormalization
OSTI Identifier: