NNLOPS description of the H$\to\! b\bar{b}$ decay with MINLO

TL;DR

This paper introduces an NNLO-accurate event generator for Higgs decay into b-quarks, matching it with parton shower simulations, and demonstrates its application in different Higgs production scenarios.

Contribution

It develops a novel NNLO-accurate event generator for Higgs to b-quark decay within the POWHEG framework using MINLO, enabling consistent matching with parton showers.

Findings

Successfully combined Higgs decay and production in a single NNLO-accurate simulation.

Provided tools for interfacing decay events with various Higgs production modes.

Released source code for community use and further studies.

Abstract

We present an event generator that describes the Higgs boson decay into $b$-quarks at next-to-next-to-leading-order (NNLO) in QCD and allows for a consistent matching to parton shower. For this purpose, we work within the POWHEG framework and employ the MINLO method to produce an NNLO-accurate H$\to\! b\bar{b}$ event sample which can further be interfaced with a generic Higgs boson production mode. The resulting events, that combine Higgs production and decay, can be matched to parton shower by means of a vetoed shower. As an example, we present a short phenomenological study for associated Higgs production (HZ) and vector boson fusion (VBF) processes. We release the source code that was used to obtain these results as an $\text{h_bbg}$ user process in POWHEG-BOX-V2. We also provide tools that enable interfacing the decay events with events for an arbitrary Higgs production mode and subsequent matching of the combined Les Houches (LH) events with a parton shower.