Speaker
Eric Braaten
(Ohio State University)
Description
The transverse momentum distribution of the Higgs at large $P_T$ is complicated by its dependence on three important energy scales: $P_T$, the top quark mass $m_t$, and the Higgs mass $m_H$. A strategy for simplifying the calculation of the cross section at large $P_T$ is to calculate only the leading terms in its expansion in $m_t^2/P_T^2$ and/or $m_H^2/P_T^2$. The expansion of the cross section in inverse powers of $P_T$ is complicated by logarithms of $P_T$ and by mass singularities. In this work, we consider the top-quark-loop contribution to the subprocess $q\bar{q}\to H+g$ at leading order in $\alpha_s$, which proceeds through a top quark loop. We show that the leading power of $1/P_T^2$ can be expressed in the form of a factorization formula that separates the large scale $P_T$ from the scale of the masses. All the dependence on $m_t$ and $m_H$ can be factorized into fragmentation amplitudes for $t \bar t \to H$ and for $t \bar t \to g$ and an endpoint contribution. This factorization approach will be useful for calculating the $P_T$ distribution at large $P_T$ to next-to-leading order in $\alpha_s$.
Primary author
Eric Braaten
(Ohio State University)
Co-author
Dr
Hong Zhang
(The Ohio State University)