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Rebecca Revelli

Publications and source records attributed to Rebecca Revelli.

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Generative Amplification with Surrogate Monte Carlo

Amplitude surrogates for LHC simulations build on generative amplification, the fact that a surrogate trained on an expensive and small training dataset describes the smooth amplitude more precisely than the training data does. Applying techniques developed for generative networks, we quantify this amplification for gluon-associated $Z$ production. Significant amplification appears in sparsely populated kinematic tails, where it matters most. Our results show how generative amplification from surrogate Monte Carlo far outperforms the density estimation in current generative networks.

hep-ph

Neural Control Variates at LO and NLO

We employ neural control variates to minimize the range of event weights and avoid negative weights for phase-space integration and event generation. A signed control variate, built from two normalizing flows, fulfills both tasks. Combined with neural importance sampling, it significantly reduces the computational cost of LO and NLO predictions. For the NLO case, our conditional neural control variate can be viewed as a trainable subtraction term, complementing the established physics subtraction schemes for enhanced sampling performance.

hep-ph

How to Trust Learned Loop Amplitudes

Higher-order theory predictions are crucial for the precision LHC program, but the time-consuming amplitude evaluation challenges the corresponding Monte-Carlo simulations. Machine-learned amplitude surrogates can resolve this problem, if we can guarantee their precision over the entire phase space. First, we show that our surrogates provide a calibrated learned uncertainty, even for non-Gaussian systematics; second, we describe how less accurate phase space regions can be identified; third, we demonstrate how the precision in these regions can be improved reliably.

hep-ph