arXiv subjects

David F. Rentería-Estrada

Publications and source records attributed to David F. Rentería-Estrada.

12 recordsLinked to original sources

arXiv2026

A quantum representation of $π$ fragmentation functions through variational quantum circuits

We present a variational quantum-circuit model for fragmentation functions (FFs). Isospin and charge-conjugation symmetries are imposed to construct an independent six-flavor basis describing charged and neutral pion production, while physics-inspired Ansätze, including logarithmic feature maps and mass thresholds, encode the relevant kinematics. This quantum architecture substantially reduces the quantum circuit redundancies and improve optimization convergence. Using the DSS14 pion FF set as a benchmark, we first develop a one-dimensional variational representation (FF-VQR) in the momentum fraction at fixed energy scale, and show how entanglement between quark and gluon FFs yields a significant improvement, with accurate results already obtained using just two variational layers. A spectral analysis further demonstrates that the quantum model achieves high expressivity with a limited number of Fourier modes, supporting its use as a compact non-perturbative parametrization suitable for DGLAP evolution. We then extend the FF-VQR to two dimensions by incorporating the energy-scale dependence. By encoding all flavor channels within a single entangled quantum circuit, the quantum model provides a unified representation with higher accuracy than an independent encoding for each partonic species.

hep-ph↗

arXiv2025

Quantum integration of decay rates at second order in perturbation theory

We present the first quantum computation of a total decay rate in high-energy physics at second order in perturbative quantum field theory. This work underscores the confluence of two recent cutting-edge advances. On the one hand, the quantum integration algorithm Quantum Fourier Iterative Amplitude Estimation (QFIAE), which efficiently decomposes the target function into its Fourier series through a quantum neural network before quantumly integrating the corresponding Fourier components. On the other hand, causal unitary in the loop-tree duality (LTD), which exploits the causal properties of vacuum amplitudes in LTD to coherently generate all contributions with different numbers of final-state particles to a scattering or decay process, leading to singularity-free integrands that are well suited for Fourier decomposition. We test the performance of the quantum algorithm with benchmark decay rates in a quantum simulator and in quantum hardware, and find accurate theoretical predictions in both settings.

quant-ph↗

arXiv2024

Vacuum amplitudes and time-like causal unitary in the loop-tree duality

We present the first proof-of-concept application to decay processes at higher perturbative orders of LTD causal unitary, a novel methodology that exploits the causal properties of vacuum amplitudes in the loop-tree duality (LTD) and is directly well-defined in the four physical dimensions of the space-time. The generation of loop- and tree-level contributions to the differential decay rates from a kernel multiloop vacuum amplitude is shown in detail, and explicit expressions are presented for selected processes that are suitable for a lightweight understanding of the method. Specifically, we provide a clear physical interpretation of the local cancellation of soft, collinear and threshold singularities, and of the local renormalisation of ultraviolet singularities. The presentation is illustrated with numerical results that showcase the advantages of the method.

hep-ph↗

arXiv2024

Theoretical predictions to differential cross sections and decay rates from the loop-tree duality

Understanding the cancellation of ultraviolet and infrared singularities in perturbative quantum field theory is of central importance for the development and automation of various theoretical tools that make accurate predictions for observables at high-energy colliders. The loop-tree duality aims to find an efficient solution by treating loop and tree-level contributions under the same foot to achieve a local cancellation of singularities at the integrand level, and thus avoiding dimensional regularisation. In this talk, we exploit the causal properties of vacuum amplitudes in the loop-tree duality representation to present different applications to physical processes at higher orders.

hep-th↗

arXiv2024

Using analytic models to describe effective PDFs

Parton distribution functions play a pivotal role in hadron collider phenomenology. They are non-perturbative quantities extracted from fits to available data, and their scale dependence is dictated by the DGLAP evolution equations. In this article, we discuss machine-assisted strategies to efficiently compute PDFs directly incorporating the scale evolution without the need of separately solving DGLAP equations. Analytical approximations to the PDFs as a function of $x$ and $Q^2$, including up to next-to-leading order effects in Quantum Chromodynamics, are obtained. The methodology is tested by reproducing the $\texttt{HERAPDF2.0}$ set and implementing the analytical expressions in benchmarking codes. It is found that the computational cost is reduced while the precision of the simulations stays well under control.

hep-ph↗

arXiv2023

Using photon-hadron production to impose restrictions on heavy-hadrons fragmentation functions

Fragmentation Functions (FF) are universal non-perturbative objects that model hadronization in some general kind of processes. They are mainly extracted from experimental data, hence constraining the parameters of the corresponding fits is crucial for achieving reliable results. As expected, the production of lighter hadrons is favoured w.r.t. heavy ones, thus we would like to exploit the precise knowledge of pion FFs to constraint the shape of kaon (or heavier) FFs. In this talk, we show how imposing specific cuts on photon-hadron production leads to relations between the $u$-started FFs. For doing so, we exploit the reconstruction of momentum fractions in terms of experimentally-accessible quantities and introduce NLO QCD + LO QED corrections to reduce the theoretical uncertainties.

hep-ph↗

arXiv2023

Constraining fragmentation functions through hadron-photon production at higher-orders

In certain situations, such as one-particle inclusive processes, it is possible to model the hadronization through Fragmentation Functions (FFs), which are universal non-perturbative functions extracted from experimental data through advanced fitting techniques. Constraining the parameters of such fits is crucial to reduce the uncertainties, and provide reliable and accurate FFs. In this article, we explore strategies to relate pion and FFs for other hadrons (in particular, kaons), comparing cross-section ratios imposing proper kinematical cuts. We exploit the phenomenology of photon-hadron production at colliders, including up to NLO QCD and LO QED corrections, and make use of accurate formulae to reconstruct the partonic momentum fractions. By studying different cuts, we manage to isolate the contribution of $u$-started FFs. Then, we relate the ratios of the $z$-spectrum for pion and kaon production, with the corresponding FFs ratios. The methodology described in this article can be used to relate FFs for any pair of hadrons, and could be further explored to keep track of the flavour of the partons undergoing the hadronization.

hep-ph↗

arXiv2022

Reconstructing parton collisions with machine learning techniques

Having access to the parton-level kinematics is important for understanding the internal dynamics of particle collisions. Here, we present new results aiming to an efficient reconstruction of parton collisions using machine-learning techniques. By simulating the collider events, we related experimentally-accessible quantities with the momentum fractions of the involved partons. We used photon-hadron production to exploit the cleanliness of the photon signal, including up to NLO QCD-QED corrections. Neural networks led to an outstanding reconstruction efficiency, suggesting a powerful strategy for unveiling the behaviour of the fundamental bricks of matter in high-energy collisions.

hep-ph↗

arXiv2022

Parton distribution effects in the direct photon production at hadron collisions

Parton distribution functions are crucial to understand the internal kinematics of hadrons. There are currently a large number of distribution functions on the market, and thanks to today's technology, performing computational analysis of the differential cross-sections has become more accessible. Despite technological advances, accurately accessing to the internal structure of hadrons remains a difficult task from a theoretical point of view. In this work, we analyze the impact on the differential cross-sections when updating the sets of parton distribution and fragmentation functions, for the production of one hadron plus a direct photon at the energy scale of RHIC and LHC experiments.

hep-ph↗

arXiv2021

Reconstructing partonic kinematics at colliders with Machine Learning

In the context of high-energy physics, a reliable description of the parton-level kinematics plays a crucial role for understanding the internal structure of hadrons and improving the precision of the calculations. Here, we study the production of one hadron and a direct photon, including up to Next-to-Leading Order Quantum Chromodynamics and Leading-Order Quantum Electrodynamics corrections. Using a code based on Monte-Carlo integration, we simulate the collisions and analyze the events to determine the correlations among measurable and partonic quantities. Then, we use these results to feed three different Machine Learning algorithms that allow us to find the momentum fractions of the partons involved in the process, in terms of suitable combinations of the final state momenta. Our results are compatible with previous findings and suggest a powerful application of Machine-Learning to model high-energy collisions at the partonic-level with high-precision.

hep-ph↗

arXiv2021

Elucidating the internal structure of hadrons through direct photon production

The accurate description of the internal structure of hadrons is a very challenging task. In order to compare the predictions with the highly-accurate experimental data, it is necessary to control any possible source of theoretical uncertainties. Thus, we can use the information extracted from final state measurement to constrain our knowledge about the internal structure of hadrons. In this work, we describe how direct photon production can be exploited to unveil details about the partonic distributions inside protons. Also, we explain how to describe QCD-QED corrections to hadron plus photon production at colliders, focusing on the accurate reconstruction of the partonic momentum fractions from experimentally accessible observables.

hep-ph↗

arXiv2021

Analysis of the internal structure of hadrons using direct photon production

Achieving a precise description of the internal structure of hadrons is a hard task, since there are several bottlenecks to obtain theoretical predictions starting from first principles. In order to complement the highly-accurate experiments, it is necessary to use ingenious strategies to impose constraints from the theory side. In this article, we describe how photons can be used to unveil the internal structure of hadrons. Using up-to-date PDFs and FFs, we explore how to describe NLO QCD plus LO QED corrections to hadron plus photon production at colliders.

hep-ph↗