ML4Jets2024

Session

Unfolding & Inference

Nov 7, 2024, 1:50 PM

LPNHE, Paris, France

Conveners

Unfolding & Inference

• Vinicius Massami Mikuni (Lawrence Berkeley National Lab. (US))

Unfolding & Inference

• Chris Pollard (University of Warwick (GB))

66. OmniFoldHI: Advanced ML Unfolding for Heavy-Ion Data

Alexandre Falcão (University of Bergen)

11/7/24, 1:50 PM

To compare collider experiments, measured data must be corrected for detector distortions through a process known as unfolding. As measurements become more sophisticated, the need for higher-dimensional unfolding increases, but traditional techniques have limitations. To address this, machine learning-based unfolding methods were recently introduced. In this work, we introduce OmniFoldHI, an...

64. Bridging the Generative Unfolding Gap

Sascha Diefenbacher (Lawrence Berkeley National Lab. (US))

11/7/24, 2:10 PM

Machine learning-based unfolding has started to establish itself as the go-to approach for precise, high-dimensional unfolding tasks. The current state-of-the-art unfolding methods can be divided into reweighting-based and generation-based methods. The latter of the two is comprised of conditional generative models, which generate new truth-level events from random noise conditioned on...

36. Measurement of Jet Track Functions with OmniFold-based Binning Corrections in ATLAS Run 2 Data

Jingjing Pan (Yale University (US))

11/7/24, 2:30 PM

Measurements of jet substructure are key to probing the energy frontier at colliders, and many of them use track-based observables which take advantage of the angular precision of tracking detectors. Theoretical calculations of track-based observables require “track functions”, which characterize the transverse momentum fraction $r_q$ carried by charged hadrons from a fragmenting quark or...

29. Full Event Particle-Level Unfolding with Variable-Length Latent Variational Diffusion

Kevin Thomas Greif (University of California Irvine (US))

11/7/24, 2:50 PM

The measurements performed by particle physics experiments must account for the imperfect response of the detectors used to observe the interactions. One approach, unfolding, statistically adjusts the experimental data for detector effects. Recently, generative machine learning models have shown promise for performing unbinned unfolding in a high number of dimensions. However, all current...

67. How to Unfold Top Decays

Sofia Palacios Schweitzer (ITP, University Heidelberg)

11/7/24, 3:10 PM

Many physics analyses at the LHC rely on algorithms to remove detector effect, commonly known as unfolding. Whereas classical methods only work with binned, one-dimensional data, Machine Learning promises to overcome both problems. Using a generative unfolding pipeline, we show how it can be build into an existing LHC analysis, designed to measure the top mass. We discuss the model-dependence...

79. Advanced techniques for SBI in collider physics

Giovanni De Crescenzo (University of Heidelberg)

11/7/24, 4:00 PM

We present an application of Simulation-Based Inference (SBI) in collider physics, aiming to constrain anomalous interactions beyond the Standard Model (SM). This is achieved by leveraging Neural Networks to learn otherwise intractable likelihood ratios. We explore methods to incorporate the underlying physics structure into the likelihood estimation process. Specifically, we compare two...

55. Towards Universal Unfolding using Denoising Diffusion

Martin Klassen (Tufts University (US))

11/7/24, 4:20 PM

Correcting for detector effects in experimental data, particularly through unfolding, is critical for enabling precision measurements in high-energy physics. However, traditional unfolding methods face challenges in scalability, flexibility, and dependence on simulations. We introduce a novel approach to multidimensional particle-wise unfolding using conditional Denoising Diffusion...

96. Parameter Estimation with Neural Simulation-Based Inference in ATLAS

Mr Arnaud Jean Maury (Université Paris-Saclay (FR))

11/7/24, 4:40 PM

Neural Simulation-Based Inference (NSBI) is a powerful class of machine learning (ML)-based methods for statistical inference that naturally handle high dimensional parameter estimation without the need to bin data into low-dimensional summary histograms. Such methods are promising for a range of measurements at the Large Hadron Collider, where no single observable may be optimal to scan over...

4. Constraining the Higgs Potential with Neural Simulation-based Inference for Di-Higgs Production

Radha Mastandrea (University of California, Berkeley)

11/7/24, 5:00 PM

Determining the form of the Higgs potential is one of the most exciting challenges of modern particle physics. Higgs pair production directly probes the Higgs self-coupling and should be observed in the near future at the High-Luminosity LHC. We explore how to improve the sensitivity to physics beyond the Standard Model through per-event kinematics for di-Higgs events. In particular, we employ...

88. Gamma-ray spectrometry of fission fragments : ML analysis of multi-dimensional spectra

Mattéo Ballu

11/7/24, 5:20 PM

The analysis of gamma radiation emitted by fission fragments has become an essential tool for studying the nuclear fission process. It allows probing the intrinsic properties of the fragments or exploring effects that are little studied experimentally, such as the sharing of excitation energy between fragments during nuclear fission.

However, the analysis of experimental fission gamma-ray...