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Approaching robust EFT limits for CP violation in the Higgs sector

Englert, Christoph; Galler, Peter; Pilkington, Andrew; Spannowsky, Michael

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Christoph Englert

Peter Galler

Andrew Pilkington


Constraining CP-violating interactions in effective field theory of dimension six faces two challenges. First, degeneracies in the multidimensional space of Wilson coefficients have to be lifted. Second, quadratic contributions of CP-odd dimension-six operators are difficult to disentangle from squared contributions of CP-even dimension-six operators and from linear contributions of dimension-eight operators. Both of these problems are present when new sources of CP violation are present in the interactions between the Higgs boson and heavy strongly interacting fermions. We show that degeneracies in the Wilson coefficients can be removed by combining measurements of Higgs-plus-two-jet production via gluon fusion with measurements of top-pair associated Higgs production. In addition, we demonstrate that the sensitivity of the analysis can be improved by exploiting the top-quark threshold in the gluon fusion process. Finally, we substantiate a perturbative argument about the validity of effective field theory by comparing the quadratic and linear contributions from CP-odd dimension-six operators and use this to show explicitly that high statistics measurements at future colliders enable the extraction of perturbatively robust constraints on the associated Wilson coefficients.


Englert, C., Galler, P., Pilkington, A., & Spannowsky, M. (2019). Approaching robust EFT limits for CP violation in the Higgs sector. Physical Review D, 99(9), Article 095007.

Journal Article Type Article
Online Publication Date May 13, 2019
Publication Date May 1, 2019
Deposit Date Jun 6, 2019
Publicly Available Date Jun 6, 2019
Journal Physical Review D
Print ISSN 2470-0010
Electronic ISSN 2470-0029
Publisher American Physical Society
Peer Reviewed Peer Reviewed
Volume 99
Issue 9
Article Number 095007


Published Journal Article (624 Kb)

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Copyright Statement
Published by the American Physical Society under the terms of<br /> the Creative Commons Attribution 4.0 International license.<br /> Further distribution of this work must maintain attribution to<br /> the author(s) and the published article’s title, journal citation,<br /> and DOI. Funded by SCOAP3.

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