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arXiv · 2202.00686

What's Anomalous in LHC Jets?

Thorsten Buss·Barry M. Dillon·Thorben Finke·Michael Krämer·Alessandro Morandini·Alexander Mück·Ivan Oleksiyuk·Tilman Plehn
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Abstract

Searches for anomalies are a significant motivation for the LHC and help define key analysis steps, including triggers. We discuss specific examples how LHC anomalies can be defined through probability density estimates, evaluated in a physics space or in an appropriate neural network latent space, and discuss the model-dependence in choosing an appropriate data parameterisation. We illustrate this for classical k-means clustering, a Dirichlet variational autoencoder, and invertible neural networks. For two especially challenging scenarios of jets from a dark sector we evaluate the strengths and limitations of each method.

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Thorsten Buss, Barry M. Dillon, Thorben Finke, Michael Krämer, Alessandro Morandini, Alexander Mück, Ivan Oleksiyuk, Tilman Plehn. 2023-10-12. What's Anomalous in LHC Jets?. https://doi.org/10.21468/scipostphys.15.4.168

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