On-Sensor Data Filtering using Neuromorphic Computing for High Energy Physics Experiments

This work describes the investigation of neuromorphic computing-based spiking neural network (SNN) models used to filter data from sensor electronics in high energy physics experiments conducted at the High Luminosity Large Hadron Collider. We present our approach for developing a compact neuromorphic model that filters out the sensor data based on the particle's transverse momentum with the goal of reducing the amount of data being sent to the downstream electronics. The incoming charge waveforms are converted to streams of binary-valued events, which are then processed by the SNN. We present our insights on the various system design choices - from data encoding to optimal hyperparameters of the training algorithm - for an accurate and compact SNN optimized for hardware deployment. Our results show that an SNN trained with an evolutionary algorithm and an optimized set of hyperparameters obtains a signal efficiency of about 91% with nearly half as many parameters as a deep neural network.Comment: Manuscript accepted at ICONS'2

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Hadronic top decays in ATLAS ttH(γγ)ttH(\gamma\gamma) measurements

Higgs production in association with top quarks ($ttH$) is predicted by the Standard Model at a rate of about 1% of the total Higgs cross section. The recent discovery of this process directly probes the Higgs-top Yukawa coupling, a critical parameter for isolating Beyond the Standard Model contributions to Higgs physics. This talk explores the top content of the $ttH(\gamma\gamma)$ analysis hadronic categories

ATLAS Measurements of the Higgs Boson Coupling to the Top Quark in the Higgs to Diphoton Decay Channel

During Run 2 of the Large Hadron Collider, the ATLAS experiment recorded proton$-$proton collision events with a center of mass energy of 13 TeV, the highest energy ever achieved in a collider. Analysis of this dataset, which corresponds to an integrated luminosity of 139 fb$^{-1}$, has provided new opportunities for precision measurements of the Higgs boson. The interaction between the Higgs boson and the top quark, the heaviest known particle, is a fundamental probe of the Higgs mechanism, which describes how Standard Model particles obtain mass. The coupling of the Higgs boson to the top quark can be directly probed through the production of a Higgs boson in association with a top-antitop quark pair ($t\bar{t}H$) at the LHC. A statistical combination of ATLAS searches in multiple Higgs boson decay channels using 79.8 fb$^{-1}$ of the Run 2 dataset yielded the first observation of $t\bar{t}H$ production at the level of $6.3\sigma$. The Higgs to diphoton ($\gamma\gamma$) decay channel is among the most sensitive for $t\bar{t}H$ measurements due to the excellent diphoton mass resolution of the ATLAS detector and the clean signature of this decay. A powerful multivariate analysis was developed to select $t\bar{t}H(\gamma\gamma)$ events based on the momenta of jets, photons, and leptons in the final state. The $t\bar{t}H$ cross section times $H\rightarrow\gamma\gamma$ branching fraction was measured to be \sigma_{t\bar{t}H}\times B_{\gamma\gamma} = 1.59 \; _{-0.39}^{+0.43} fb using the full Run 2 ATLAS dataset. Top quarks were reconstructed with high probability in selected $t\bar{t}H(\gamma\gamma)$ events. Following the observation of the $t\bar{t}H$ process, a direct measurement of the CP properties of the Higgs-top interaction was carried out in the $H\rightarrow\gamma\gamma$ decay channel. A CP-sensitive multivariate categorization was developed using reconstructed top quark variables, yielding an observed $t\bar{t}H$ significance of 5.2$\sigma$ and an upper limit on the cross section of single-top-plus-Higgs ($tH$) production of 11.6 times the SM expectation. The observed data excludes a fully CP odd Higgs-top coupling at the level of 3.9$\sigma$, and the CP mixing angle is constrained to $|\alpha|>43^\circ$ at 95\% confidence level

ATLAS Measurements of the Higgs Boson Coupling to the Top Quark in the Higgs to Diphoton Decay Channel

During Run 2 of the Large Hadron Collider, the ATLAS experiment recorded proton--proton collision events with a center of mass energy of 13 TeV, the highest energy ever achieved in a collider. Analysis of this dataset, which corresponds to an integrated luminosity of 139 fb$^{-1}$, has provided new opportunities for precision measurements of the Higgs boson. The interaction between the Higgs boson and the top quark, the heaviest known particle, is a fundamental probe of the Higgs mechanism, which describes how Standard Model particles obtain mass. The coupling of the Higgs boson to the top quark can be directly probed through the production of a Higgs boson in association with a top-antitop quark pair ($t\bar{t}H$) at the LHC. A statistical combination of ATLAS searches in multiple Higgs boson decay channels using 79.8 fb$^{-1}$ of the Run 2 dataset yielded the first observation of $t\bar{t}H$ production at the level of $6.3\sigma$. The Higgs to diphoton ($\gamma\gamma$) decay channel is among the most sensitive for $t\bar{t}H$ measurements due to the excellent diphoton mass resolution of the ATLAS detector and the clean signature of this decay. A powerful multivariate analysis was developed to select $t\bar{t}H(\gamma\gamma)$ events based on the momenta of jets, photons, and leptons in the final state. The $t\bar{t}H$ cross section times $H\rightarrow\gamma\gamma$ branching fraction was measured to be \sigma_{t\bar{t}H}\times B_{\gamma\gamma} = 1.59 \; _{-0.39}^{+0.43} fb using the full Run 2 ATLAS dataset. Top quarks were reconstructed with high probability in selected $t\bar{t}H(\gamma\gamma)$ events. Following the observation of the $t\bar{t}H$ process, a direct measurement of the CP properties of the Higgs-top interaction was carried out in the $H\rightarrow\gamma\gamma$ decay channel. A CP-sensitive multivariate categorization was developed using reconstructed top quark variables, yielding an observed $t\bar{t}H$ significance of 5.2$\sigma$ and an upper limit on the cross section of single-top-plus-Higgs ($tH$) production of 11.6 times the SM expectation. The observed data excludes a fully CP odd Higgs-top coupling at the level of 3.9$\sigma$, and the CP mixing angle is constrained to |\alpha|>43^\circ at 95\% confidence level

Progress in End-to-End Optimization of Detectors for Fundamental Physics with Differentiable Programming

In this article we examine recent developments in the research area concerning the creation of end-to-end models for the complete optimization of measuring instruments. The models we consider rely on differentiable programming methods and on the specification of a software pipeline including all factors impacting performance -- from the data-generating processes to their reconstruction and the extraction of inference on the parameters of interest of a measuring instrument -- along with the careful specification of a utility function well aligned with the end goals of the experiment. Building on previous studies originated within the MODE Collaboration, we focus specifically on applications involving instruments for particle physics experimentation, as well as industrial and medical applications that share the detection of radiation as their data-generating mechanism