No Track left behind: Graph-based Vertexing for long-lived Particle Reconstruction

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Kriewald, Jonathan
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911187780763648
author Kriewald, Jonathan
author_facet Kriewald, Jonathan
contents Reconstruction of displaced vertices is a cornerstone of both precision flavour physics and searches for long-lived particles (LLPs) at colliders. While existing vertexing algorithms are highly optimised for primary and short-lived secondary vertices, they face limitations when confronted with the large displacements and heterogeneous topologies characteristic of LLP decays. In this work we present a new approach to displaced vertex reconstruction combining an initialisation-free robust vertex fitter with a graph-based track clustering strategy. The algorithm is implemented as a self-contained Delphes module and can be straightforwardly integrated into existing detector cards, providing a turn-key tool for phenomenological studies. This plug-and-play functionality fills a gap left by public software frameworks, which either lack displaced-vertex capabilities or are not readily usable in fast-simulation environments. We validate our approach in an IDEA-like FCC-ee detector, using Higgs-strahlung $e^+e^- \to Zh$ with exotic $h\to NN$ decays as a benchmark process. We demonstrate excellent efficiency, resolution, and purity across a broad range of lifetimes, and derive model-independent projections for the FCC-ee sensitivity to exotic Higgs branching fractions.
format Preprint
id arxiv_https___arxiv_org_abs_2510_00856
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle No Track left behind: Graph-based Vertexing for long-lived Particle Reconstruction
Kriewald, Jonathan
High Energy Physics - Phenomenology
High Energy Physics - Experiment
Reconstruction of displaced vertices is a cornerstone of both precision flavour physics and searches for long-lived particles (LLPs) at colliders. While existing vertexing algorithms are highly optimised for primary and short-lived secondary vertices, they face limitations when confronted with the large displacements and heterogeneous topologies characteristic of LLP decays. In this work we present a new approach to displaced vertex reconstruction combining an initialisation-free robust vertex fitter with a graph-based track clustering strategy. The algorithm is implemented as a self-contained Delphes module and can be straightforwardly integrated into existing detector cards, providing a turn-key tool for phenomenological studies. This plug-and-play functionality fills a gap left by public software frameworks, which either lack displaced-vertex capabilities or are not readily usable in fast-simulation environments. We validate our approach in an IDEA-like FCC-ee detector, using Higgs-strahlung $e^+e^- \to Zh$ with exotic $h\to NN$ decays as a benchmark process. We demonstrate excellent efficiency, resolution, and purity across a broad range of lifetimes, and derive model-independent projections for the FCC-ee sensitivity to exotic Higgs branching fractions.
title No Track left behind: Graph-based Vertexing for long-lived Particle Reconstruction
topic High Energy Physics - Phenomenology
High Energy Physics - Experiment
url https://arxiv.org/abs/2510.00856