3,052 research outputs found
Note on Anomalous Higgs-Boson Couplings in Effective Field Theory
We propose a parametrization of anomalous Higgs-boson couplings that is both
systematic and practical. It is based on the electroweak chiral Lagrangian,
including a light Higgs boson, as the effective field theory (EFT) at the
electroweak scale . This is the appropriate framework for the case of
sizeable deviations in the Higgs couplings of order from the Standard
Model, considered to be parametrically larger than new-physics effects in the
sector of electroweak gauge interactions. The role of power counting in
identifying the relevant parameters is emphasized. The three relevant scales,
, the scale of new Higgs dynamics , and the cut-off ,
admit expansions in and . The former corresponds
to an organization of operators by their canonical dimension, the latter by
their loop order or chiral dimension. In full generality the EFT is thus
organized as a double expansion. However, as long as the EFT
systematics is closer to the chiral counting. The leading effects in the
consistent approximation provided by the EFT, relevant for the presently most
important processes of Higgs production and decay, are given by a few
(typically six) couplings. These parameters allow us to describe the properties
of the Higgs boson in a general and systematic way, and with a precision
adequate for the measurements to be performed at the LHC. The framework can be
systematically extended to include loop corrections and higher-order terms in
the EFT.Comment: 7 pages, no figures; typos corrected; references adde
Normally ordered forms of powers of differential operators and their combinatorics
We investigate the combinatorics of the general formulas for the
powers of the operator h∂k, where h is a central element of a ring
and ∂ is a differential operator. This generalizes previous work on
the powers of operators h∂. New formulas for the generalized Stirling
numbers are obtained.Ministerio de EconomÃa y competitividad MTM2016-75024-PJunta de AndalucÃa P12-FQM-2696Junta de AndalucÃa FQM–33
Complete One-Loop Renormalization of the Higgs-Electroweak Chiral Lagrangian
Employing background-field method and super-heat-kernel expansion, we compute
the complete one-loop renormalization of the electroweak chiral Lagrangian with
a light Higgs boson. Earlier results from purely scalar fluctuations are
confirmed as a special case. We also recover the one-loop renormalization of
the conventional Standard Model in the appropriate limit.Comment: 15 pages, no figures; v2: reference and comments added, typos fixed,
matches published versio
Hybridization between wild and cultivated potato species in the Peruvian Andes and biosafety implications for deployment of GM potatoes
The nature and extent of past and current hybridization between cultivated potato and wild relatives in nature is of interest to crop evolutionists, taxonomists, breeders and recently to molecular biologists because of the possibilities of inverse gene flow in the deployment of genetically-modified (GM) crops. This research proves that natural hybridization occurs in areas of potato diversity in the Andes, the possibilities for survival of these new hybrids, and shows a possible way forward in case of GM potatoes should prove advantageous in such areas
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