Limitations and opportunities of off-shell coupling measurements

Englert, Christoph; Spannowsky, Michael

Abstract

Indirect constraints on the total Higgs width Γh from correlating Higgs signal strengths with cross-section measurements in the off-shell region for p(g)p(g)→4ℓ production have received considerable attention recently, and the CMS Collaboration have published a first measurement. We revisit this analysis from a new physics and unitarity constraints perspective and conclude that limits on Γh obtained in this fashion are not reliable unless we make model-specific assumptions, which cannot be justified at the current stage of the LHC program. Relaxing the Γh interpretation, we discuss the merits of high invariant mass cross-section measurements in the context of Higgs CP analyses, higher-dimensional operator testing, and resolved new physics in the light of electroweak precision constraints beyond effective theory limitations. Furthermore, we show that a rather model-independent LHC constraint can be obtained from adapting the gg→4ℓ analysis to the weak boson fusion channels at lower statistical yield.

Citation

Englert, C., & Spannowsky, M. (2014). Limitations and opportunities of off-shell coupling measurements. Physical Review D, 90(5), Article 053003. https://doi.org/10.1103/physrevd.90.053003

• Journal Article Type: Article
• Acceptance Date: May 12, 2014
• Online Publication Date: Sep 3, 2014
• Publication Date: Sep 3, 2014
• Deposit Date: Dec 12, 2014
• Publicly Available Date: Apr 27, 2015
• Journal: Physical Review D - Particles, Fields, Gravitation, and Cosmology
• Print ISSN: 1550-7998
• Electronic ISSN: 1550-2368
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 90
• Issue: 5
• Article Number: 053003
• DOI: https://doi.org/10.1103/physrevd.90.053003
• Public URL: https://durham-repository.worktribe.com/output/1448237