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Title: Determinations of Vus using inclusive hadronic τ decay data

Two methods for determining |V us| employing inclusive hadronic ττ decay data are discussed. The first is the conventional flavor-breaking sum rule determination whose usual implementation produces results ~3σ low compared to three-family unitary expectations. The second is a novel approach combining experimental strange hadronic ττ distributions with lattice light-strange current–current two-point function data. In preliminary explorations of the latter show the method promises |V us| determinations are competitive with those from K ℓ3 and Γ[π μ2]/Γ[π μ2]. For the former, systematic issues in the conventional implementation are investigated. Unphysical dependences of |V us| on the choice of sum rule weight, w, and upper limit, s 0, of the weighted experimental spectral integrals are observed, the source of these problems identified and a new implementation which overcomes these problems developed. The lattice results are shown to provide a tool for quantitatively assessing truncation uncertainties for the slowly converging D=2 OPE series. Our results for |V us| from this new implementation are shown to be free of unphysical w- and s0-dependences, and ~0.0020 higher than those produced by the conventional implementation. With preliminary new Kπ branching fraction results as input, we find |V us| in excellent agreement with that obtained frommore » K ℓ3, and compatible within errors with expectations from three-family unitarity.« less
 [1] ;  [2] ;  [2] ;  [3] ;  [3] ;  [4]
  1. York Univ., Toronto, ON (Canada). Mathematics and Statistics; Univ. of Adelaide, SA (Australia). CSSM
  2. York Univ., Toronto, ON (Canada). Physics and Astronomy
  3. Brookhaven National Lab. (BNL), Upton, NY (United States). RIKEN-BNL Research Center
  4. Univ. of Adelaide, SA (Australia). CSSM
Publication Date:
Report Number(s):
Journal ID: ISSN 0217-7323; KA2401012; TRN: US1701681
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Modern Physics Letters A
Additional Journal Information:
Journal Volume: 31; Journal Issue: 29; Journal ID: ISSN 0217-7323
World Scientific Publishing
Research Org:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CKM; sum rules; τ decay; unitarity; hadronic; flavor; CP; violation
OSTI Identifier: