Exploring the potential of FCC-hh to search for particles from $B$ mesons

TL;DR

This paper evaluates the FCC-hh collider's potential to detect particles from B meson decays, highlighting its increased sensitivity to heavy neutral leptons compared to the LHC due to higher production rates.

Contribution

The study demonstrates the enhanced sensitivity of FCC-hh for heavy neutral leptons with masses below B mesons, considering various detector configurations and decay volumes.

Findings

FCC-hh could produce 30 times more B mesons than LHC.

FCC-hh can significantly extend the search reach for heavy neutral leptons.

Displaced decay volume placement affects detection sensitivity.

Abstract

The Future Circular Collider (FCC-hh) is a proposed successor of the Large Hadron Collider (LHC). FCC-hh would push both the energy and intensity frontiers of searches for new physics particles. In particular, due to higher energy and luminosity than at the LHC, at FCC-hh there would be produced around $\simeq\!30$ times larger amount of $B$ mesons and $\simeq 120$ times of $W$ bosons, which then may decay into feebly interacting particles. In this paper we demonstrate the potential of FCC-hh by studying its sensitivity to heavy neutral leptons (HNLs) with masses $m_{N}<m_{B}$. We consider various locations of a displaced decay volume embedded in the planned infrastructure of FCC-hh. We demonstrate that FCC-hh may substantially improve the reach of the parameter space of HNLs as compared to the searches proposed at the LHC.