Higgs boson production in high energy proton-nucleus collisions

TL;DR

This paper investigates Higgs boson production in high energy proton-nucleus collisions, comparing different theoretical frameworks and highlighting the role of gluon distributions and medium density effects.

Contribution

It introduces a hybrid model for Higgs production in dense media and compares k_t factorization with TMD frameworks using CGC inputs.

Findings

k_t factorization matches TMD results in dilute media

k_t factorization breaks down in dense media

hybrid model effectively describes reactions in dense environments

Abstract

We study Higgs boson production from gluon-gluon fusion at mid-rapidity in high energy proton-nucleus collisions. For this process the presently still little known gluon distribution function $h_1^{\perp g}$ gives a numerically relevant contribution. We show by explicite calculation that using CGC (color glass condensate) model input the result obtained in the naive k_t factorization approach matches the result obtained in the TMD factorization framework for a dilute medium. We also verify the earlier finding that the k_t factorization formalism for Higgs production breaks down in a dense medium. In doing so we formulate a hybrid model which allows one to treat such reactions theoretically.