We use cookies to ensure that we give you the best experience on our website. By continuing to browse this repository, you give consent for essential cookies to be used. You can read more about our Privacy and Cookie Policy.

Durham Research Online
You are in:

Approaching robust EFT limits for CP violation in the Higgs sector.

Englert, Christoph and Galler, Peter and Pilkington, Andrew and Spannowsky, Michael (2019) 'Approaching robust EFT limits for CP violation in the Higgs sector.', Physical review D., 99 (9). 095007.


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.

Item Type:Article
Full text:(VoR) Version of Record
Available under License - Creative Commons Attribution.
Download PDF
Publisher Web site:
Publisher statement:Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.
Date accepted:No date available
Date deposited:06 June 2019
Date of first online publication:13 May 2019
Date first made open access:06 June 2019

Save or Share this output

Look up in GoogleScholar