LHEReader: Simplified Conversion from Les Houches Event Files to ROOT Format

TL;DR

The application of this program is illustrated through the simulation of $pp\rightarrow ZH$, with the events at the parton level after hard-scatter event generation as well as after the stage of fast simulation using \MadAnalysis.

Abstract

We present the \textsc{LHEReader} program that converts an Les Houches Event file into a \Root file allowing one to subsequently analyze the file using \Root. We evaluate the performance of this conversion by simulating $pp\to jj$ and $e^+e^- \to ZH$. The application of this program is illustrated through the simulation of $pp\rightarrow ZH$, with the $Z\to\ell^+\ell^-$ and $H\to b\bar{b}$, analyzing the events at the parton level after hard-scatter event generation as well as after the stage of fast simulation using \MadAnalysis. The analysis is implemented in \Root demonstrating the use of this program. The program is available here: https://github.com/amanmdesai/LHEReader

Figures (5)

• Figure 1: A representative Leading-order Feynman diagram for $pp\to Z H$ production.
• Figure 2: Screenshot of an event as stored in a sample LHE File.
• Figure 3: Distributions of selected kinematic observables at the reconstructed level: muon transverse momentum, electron transverse momentum, $b$-jet transverse momentum, and the transverse momenta of the pair of $b$-jets.
• Figure 4: Di-lepton invariant mass distributions: $m_{ee}$ (left) in the two-electron channel and $m_{\mu\mu}$ (right) in the two-muon channel.
• Figure 5: Higgs boson mass distribution at parton level (left) and reconstructed level (right).