Year: 2026
Type: preprint
Abstract: We use the angular distribution of top quark pairs ($t\bar{t}$) in the semileptonic final state $b\bar{b}\,\ellνq\bar{q}'$ to construct an anomaly detector for non-$t\bar{t}$ events. Wigner $D$ functions expand the distribution with coefficients determined by orthogonal series density estimation. Its equiprobable surfaces bin the events, the non-$t\bar{t}$ concentrate at low $t\bar{t}$ density. The separation is quantified by the Kullback-Leibler divergence, which makes connection to variational autoencoders. The performance is comparable to normalizing flows at parton level, but is limited by jet assignments at reconstruction level.
Source: arXiv (Cornell University)
Authors: Whitten, Alex, Cicero, John, Hong, Tae Min
Institution: University of Pittsburgh
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funder: U.S. Department of Energy
OpenAlex ID: W7222948604