arXiv subjects

Nikos Konstantinidis

Publications and source records attributed to Nikos Konstantinidis.

4 recordsLinked to original sources

arXiv2026

AMD Versal AI-Engines for fixed latency environments

Complex, high-throughput data acquisition and processing systems, such as those used in high-energy physics experiments, are increasingly moving sophisticated pattern recognition and data compression algorithms closer to the sensors themselves. To meet these needs, programmable device manufacturers offer multi-silicon die packages that commonly include dedicated co-processors within the same package. We present a technical study of a new family of such co-processors from AMD Xilinx, the Adaptive Intelligence (AI) Engine, or AIE, as part of the Versal architecture. Specifically, we focus on the deployment capabilities of AIEs in fixed latency environments such as those typically found in colliding beam experiments like those at the Large Hadron Collider. We evaluate the performance of a vectorised implementation of both a Boosted Decision Tree (BDT) and a Convolutional Neural Network (CNN), thereby demonstrating the feasibility of deploying AIEs for ML applications in such environments and their use as possible alternatives to traditional programmable logic-based implementations.

hep-ex↗

arXiv2026

End-to-end optimisation of HEP triggers

High-energy physics experiments face extreme data rates, requiring real-time trigger systems to reduce event throughput while preserving sensitivity to rare processes. Trigger systems are typically constructed as modular chains of sequentially optimised algorithms, including machine learning models. Each algorithm is optimised for a specific local objective with no guarantee of overall optimality. We instead formulate trigger design as a constrained end-to-end optimisation problem, treating all stages- including data encoding, denoising, clustering, and calibration- as components of a single differentiable system trained against a unified physics objective. The framework jointly optimises performance while incorporating physics and deployment constraints. We demonstrate this approach on a hardware multi-jet trigger inspired by the ATLAS High-Luminosity Large Hadron Collider design. Using Higgs boson pair production as a benchmark, we observe x2-4 improvement in true-positive rate at fixed false-positive rate, while preserving interpretable intermediate physics objects and monotonic calibration constraints. These results highlight end-to-end optimisation as a practical paradigm for next-generation real-time event selection systems.

hep-ex↗

arXiv2015

Non-resonant Higgs pair production in the $b\bar{b}b\bar{b}$ final state at the LHC

We present a particle-level study of the Standard Model non-resonant Higgs-pair production process in the $b\bar{b}b\bar{b}$ final state, at the Large Hadron Collider at $\sqrt{s}=14$ TeV. Each Higgs boson is reconstructed from a pair of close-by jets formed with the anti-$k_t$ jet clustering algorithm, with radius parameter $R=0.4$. Given the kinematic properties of the produced Higgs bosons, this Higgs reconstruction approach appears to be more suitable than the use of large-radius jets that was previously proposed in the literature. We find that the sensitivity for observing this final state can be improved significantly when the full set of uncorrelated angular and kinematic variables of the $4b$ system is exploited, leading to a statistical significance of 1.8 per experiment with an integrated luminosity of 3 ab$^{-1}$.

hep-ph↗

arXiv2014

Boosted $hh \rightarrow b\bar{b}b\bar{b}$: a new topology in searches for TeV-scale resonances at the LHC

It is widely believed that fully hadronic final states are not competitive in searches for new physics at the Large Hadron Collider due to the overwhelming QCD backgrounds. In this letter, we present a particle-level study of the topology arising when a TeV-scale resonance decays to two Higgs bosons and these subsequently decay to $b\bar{b}$, leading to two back-to-back boosted dijet systems. We show that selecting events with this topology dramatically reduces all backgrounds, thus enabling very competitive searches for new physics in a variety of models. For a resonance with mass 1 TeV and width around 60 GeV, we find that ATLAS or CMS could have a sensitivity to a $σ\times BR$ as small as a few fb with the LHC data collected in 2012. These conclusions are also relevant to the boosted $Zh\rightarrow b\bar{b}b\bar{b}$ and $ZZ\rightarrow b\bar{b}b\bar{b}$ final states, which would further increase the potential sensitivity to new physics as well as to Standard Model processes like longitudinal vector boson scattering.

hep-ex↗