Vorschau

PDF, Englisch - Hauptdokument Download (8MB) | Lizenz: Build from the SMEFT up - SMEFT global analyses as a bottom-up approach to constrain BSM physics von Geoffray, Emma steht unter einer Creative Commons Namensnennung 4.0

Abstract

Measurements at the Large Hadron Collider have so far been remarkably compatible with the Standard Model. Standard Model effective field theory (SMEFT) global analyses are an established framework to re-interpret combinations of measurements as constraints on physics beyond the Standard Model (BSM). But the power of these analyses is that they can also act as a springboard to constrain ultraviolet models. We present this bottom-up approach to setting limits on BSM physics in two steps. First, we upgrade an existing SMEFT global analysis for Higgs and electroweak processes, adding over 30 new measurements and constraining two additional operators. We compare the results obtained through profile likelihood and Bayesian marginalization frameworks. We find that the results have a good level of agreement. Differences are observed when a distribution with an under-fluctuation in the high kinematic region leads to volume effects in the marginalization treatment. Second, we show how to extend the previous SMEFT analysis with a matching procedure to derive constraints on the parameters of a UV model. We then perform a global analysis for the heavy vector triplet model. Our results highlight the importance of theory uncertainties arising from the matching. We discuss the complementarity of constraints from SMEFT analyses and model-specific searches.