SusHi: A program for the calculation of Higgs production in gluon fusion and bottom-quark annihilation in the Standard Model and the MSSM

TL;DR

SusHi provides a comprehensive, flexible framework for Higgs production predictions at hadron colliders, delivering inclusive and differential cross sections for gluon fusion and bottom-quark annihilation in both the SM and MSSM. It combines NNLO QCD results with NLO QCD and EW corrections, and includes SUSY-loop effects from (s)top and (s)bottom sectors, multiple renormalization schemes, and $\tan\beta$-enhanced resummation via $\Delta_b$, with optional Higgs-mass inputs from FeynHiggs. The program interfaces with external tools (LHAPDF, FeynHiggs) and mature codes (ggh@nnlo, bbh@nnlo), enabling reliable mass spectra, couplings, and cross sections across parameter scans. By providing differential distributions and cuts, as well as comprehensive MSSM support, SusHi significantly aids experimental analyses and SUSY Higgs phenomenology at the LHC and future colliders.

Abstract

This article describes the code SusHi (for "Supersymmetric Higgs") which calculates the cross sections $pp/p\bar{p}\rightarrowφ+X$ in gluon fusion and bottom-quark annihilation in the SM and the MSSM, where $φ$ is any of the neutral Higgs bosons within these models. Apart from inclusive cross sections up to NNLO QCD, differential cross sections with respect to the Higgs' transverse momentum $p_T$ and (pseudo-)rapidity $y(η)$ can be calculated through NLO QCD. In case of gluon fusion, SusHi contains NLO QCD contributions from the third family of quarks and squarks, NNLO corrections due to top-quarks, approximate NNLO corrections due to top-squarks, and electro-weak effects. It supports various renormalization schemes for the sbottom sector and the bottom Yukawa coupling, as well as resummation effects of higher order $\tanβ$-enhanced sbottom contributions. SusHi provides a link to FeynHiggs for the calculation of the Higgs masses.

Figures (4)

• Figure 1: Feynman diagram inducing an effective coupling of the bottom-quarks to $H_u$. The coupling is proportional to $\mu t_\beta$ and can be resummed in $\Delta_b$.
• Figure 2: Example Feynman diagrams contributing to $\tilde{a}_q^{\phi,(1)}$: gluon-squark contribution (left), gluino-quark-squark contribution (middle) and gluino-quark-squark contribution (right). The latter is partially resummed by the usage of $\Delta_b$ from Eq. (\ref{['eq:deltab']}).
• Figure 3: Feynman diagrams showing the associated production process $gg\rightarrow (b\overline{b})\phi$ in the $4$FS (left) and bottom-quark annihilation in the $5$FS (right).
• Figure 4: Internal workflow of SusHi. Red boxes indicate interaction with the user, who has to provide an input and gets an output file, if no error messages are shown. Green boxes refer to external code (see text), which is linked to/included in SusHi.