# Fitting the b-quark PDF as a massive-b scheme: Higgs production in bottom fusion

## TL;DR

This paper introduces a novel massive-b scheme for Higgs production via bottom fusion, allowing for accurate calculations with an independently parametrized b quark PDF that retains mass effects.

## Contribution

It extends the FONLL method to include a non-perturbatively determined b PDF, enabling more precise modeling of b-quark initiated processes at hadron colliders.

## Key findings

- The approach improves the accuracy of Higgs production predictions in bottom fusion.
- It overcomes high-order perturbative limitations of standard massive four-flavor schemes.
- The method generalizes previous deep-inelastic scattering results to hadronic collisions.

## Abstract

We show that a simple and accurate approach to the computation of hadron collider processes involving initial-state $b$ quarks can be obtained by introducing an independently parametrized b PDF. We use the so-called FONLL method for the matching of a scheme in which the b quark is treated as a massless parton to that in which it is treated as a massive state, and extend it to the case in which the b quark PDF is not necessarily determined by perturbative matching conditions. This generalizes to hadronic collisions analogous results previously obtained for deep-inelastic scattering. The results corresponds to a `massive b' scheme, in which b mass effects are retained, yet the b quark is endowed with a PDF. We specifically study Higgs production in bottom fusion, and show that our approach overcomes difficulties related to the fact that in a standard massive four-flavor scheme b-quark induced processes only start at high perturbative orders.