QED-enhanced PDF implications for the Higgs sector

TL;DR

This paper investigates how electroweak corrections and photon-inclusive PDFs affect Higgs production processes, demonstrating that recent photon PDF formalisms stabilize predictions with modest cross-section variations.

Contribution

It introduces the impact of QED-enhanced PDFs and the LUX formalism on electroweak corrections in Higgs sector predictions, improving theoretical stability.

Findings

LUX formalism stabilizes photon PDF dependence

Electroweak corrections cause 3-4% cross-section variations

QED-enhanced PDFs influence Higgs production predictions

Abstract

In this work, we examine the implications of electroweak corrections beyond leading order for processes of special interest in the Higgs sector. We especially explore the role of these corrections given the introduction of an explicit parton distribution function (PDF) for the photon in the proton, an object which emerges necessarily in global PDF fits which include QED effects (i.e., QED-enhanced PDFs). We concentrate on several representative cases, including total Higgs-production cross sections through gluon fusion, $gg \to H$, vector-boson fusion (VBFH), and associated production, $pp \to VH$; we also examine differential distributions, taking a representative Higgs-strahlung process, $pp \to W^+H$. We find that the recently developed LUX formalism for the photon PDF significantly stabilizes the PDF dependence of both QED-PDF and electroweak corrections in the Higgs sector, while leaving overall $\sim\!3\!-\!4\%$ cross-section-level variations, depending on the chosen QED-enhanced PDF. We illustrate this QED-enhanced PDF dependence by exploring predictions based upon recent analyses of the CTEQ-TEA, MSHT, and NNPDF analysis groups, fitted either at NNLO or approximate N3LO in QCD.