16–18 Jun 2025
Columbia University, Nevis Laboratories
America/New_York timezone

Isolating Unisolated Upsilons with Anomaly Detection in CMS Open Data

18 Jun 2025, 10:30
15m
Nevis Science Center (Columbia University, Nevis Laboratories)

Nevis Science Center

Columbia University, Nevis Laboratories

Speaker

Radha Mastandrea (UC Berkeley)

Description

We present the first study of anti-isolated Upsilon decays to two muons (Υ → μ+μ−) in proton-proton collisions at the Large Hadron Collider. Using a machine learning (ML)-based anomaly detection strategy (CATHODE), we “rediscover” the Υ in 13 TeV CMS Open Data from 2016, despite overwhelming anti-isolated backgrounds. CATHODE can elevate the signal significance to 6.4σ (starting from 1.6σ using the dimuon mass spectrum alone), far outperforming classical cut-based methods on individual observables. Our work demonstrates that it is possible and practical to find real signals in experimental collider data using ML-based anomaly detection. Additionally, we distill a readily-accessible benchmark dataset from the CMS Open Data to facilitate future anomaly detection development. THIS TALK IS THE FIRST OF TWO PARTS.

Primary authors

Prof. Benjamin Nachman (Stanford) Prof. Jesse Thaler (MIT) Radha Mastandrea (UC Berkeley) Dr Rikab Gambhir (MIT)

Presentation materials