@Article{Cirigliano_etal2010,
author="Cirigliano, V.
and Jenkins, J. P.
and Gonzalez-Alonso, M.",
title="Semileptonic decays of light quarks beyond the Standard Model",
journal="Nuclear Physics B",
year="2010",
publisher="Elsevier Science Bv",
volume="830",
number="1-2",
pages="95--115",
optkeywords="Semileptonic decays; CKM unitarity; Effective theory; Beyond the Standard Model",
abstract="We describe non-standard contributions to semileptonic processes in a model independent way in terms of in SU(2)(L) x U(1)(Y) invariant effective lagrangian at the weak scale, front which we derive the low-energy effective lagrangian governing muon and beta decays. We find that the deviation from Cabibbo universality, Delta(CKM) equivalent to vertical bar V-ud vertical bar(2) + vertical bar V-us vertical bar(2) + vertical bar V-ub vertical bar(2) -- 1, receives contributions from four effective operators. The phenomenological bound Delta(CKM) = (-1 +/- 6) x 10(-4) provides strong constraints on all four operators, corresponding to art effective scale Lambda > 11 TeV (90{\%} CL). Depending on the operator, this constraint is at the same level or better then the Z pole observables. Conversely, precision electroweak constraints alone would allow universality violations as large as Delta(CKM) = -0.01 (90{\%} CL). An observed Delta(CKM) not equal 0 at this level Could be explained in terms of a single four-fermion operator which is relatively poorly constrained by electroweak precision measurements.",
optnote="ISI:000275150000003",
optnote="exported from refbase (https://references.ific.uv.es/refbase/show.php?record=497), last updated on Thu, 01 Nov 2012 20:03:56 +0000",
issn="0550-3213",
doi="10.1016/j.nuclphysb.2009.12.020",
opturl="http://lanl.arxiv.org/abs/0908.1754",
opturl="https://doi.org/10.1016/j.nuclphysb.2009.12.020",
language="English"
}