Hadron production through Higgs decay at next-to-leading order in the general-mass variable-flavor-number scheme

Abstract

It is known that about $60\%$ of all Higgses produced at the CERN-LHC decay into a pair of bottom quarks. Bottoms quickly hadronize, in most cases, into bottom-flavored (B) hadrons before they decay. Therefore, the study of scaled-energy distribution of B-mesons in the decay process $H\to B+Jets$ can be considered as a channel to search for the Higgs characteristics. In all previous studies, authors have ignored the mass effect of b-quarks as well as B-mesons by working in the massless scheme. In this work we, for the first time, study the mass effect of b-quarks as well as produced mesons on the scaled-energy ($x_B$) distribution of B-mesons by working in the massive scheme or general-mass variable-flavor-number scheme (GM-VFNs). We find that the meson mass is responsible for a significant enhancement of partial decay width in the low-$x_B$ region while the b-quark mass leads to an enhancement of the partial decay rate in the peak region and above.

Figures (5)

• Figure 1: Higgs decay Feynman diagrams at NLO: (A) tree-level contribution; (B) vertex correction and a combination of mass and wave function renormalization; (C) real radiations.
• Figure 2: $1/\tilde{\Gamma}_0\times d\Gamma(H\to B +X)/dx_B$ as a function of $x_B$ in the GM-VFN scheme. The NLO result (blue dot-dashed line) is compared to the LO one (black solid line) and broken up into the contributions due to $b\to B$ (green dotted line) and $g\to B$ (red dashed line) fragmentation. Here we set $m_B=0$.
• Figure 3: $1/\Gamma_0\times d\Gamma(H\to B +X)/dx_B$ as a function of $x_B$ at NLO. The GM-VFN ($m_b\neq 0$) results with (red dashed) and without finite-$m_B$ corrections (blue dot-dashed) are compared to the ZM-VFN ($m_b=0$) result for $m_B=0$ (black solid line).
• Figure 4: $1/\Gamma_0\times d\Gamma(H\to B +X)/dx_B$ as a function of $x_B$ at NLO in the GM-VFN ($m_b\neq 0$) scheme with (red dashed line) and without (blue solid line) finite-$m_B$ corrections. Both results are normalized to the ZM-VFN result ($m_b=0$) for $m_B=0$. Here, we set $\mu=m_H$.
• Figure 5: $1/\tilde{\Gamma}_0\times d\Gamma(H\to B +X)/dx_B$ as a function of $x_B$ at NLO in the GM-VFN scheme considering various values for the scale $\mu$, i.e. $m_H/2\le \mu\le 2m_H$. The result for $\mu=m_H$ is also shown (black dashed line).