arXiv subjects

Armando Bermudez Martinez

Publications and source records attributed to Armando Bermudez Martinez.

6 recordsLinked to original sources

arXiv2023

Transformation of transverse momentum distributions from Parton Branching to Collins-Soper-Sterman framework

Two main frameworks for defining transverse momentum dependent (TMD) parton densities are the Collins-Soper-Sterman (CSS) formalism, and the Parton Branching (PB) approach. While PB-TMDs have an explicit dependence on a single scale which is used to evolve PB-TMDs in momentum space, TMDs defined in CSS formalism present a double-scale evolution in renormalization and rapidity scales, via a pair of coupled evolution equations. In this letter I leverage the Collins-Soper kernel determined from simulated Drell Yan transverse momentum spectra using PB-TMDs, and provide, for the first time, the transformation of TMD parton distributions from the PB framework to the CSS formalism. The evolved PB-TMDs in $b$-space are compared to the recently released, unpolarized TMD distribution ART23.

hep-ph↗

arXiv2022

Determination of Collins-Soper kernel from cross-sections ratios

We present a novel method of extraction of the Collins-Soper kernel directly from the comparison of differential cross-sections measured at different energies. Using this method, we analyze the pseudo-data generated by the CASCADE event generator and extract the Collins-Soper kernel predicted by the parton-branching model in the wide range of transverse distances. The procedure can be applied, with minor modifications, to the real measured data for Drell-Yan and SIDIS processes.

hep-ph↗

arXiv2022

Drell Yan production in the parton branching method and POWHEG matching

As part of the DESY summer student program 2021, transverse momentum dependent (TMD) parton distributions obtained from the Parton Branching (PB) method were combined with next-to-leading-order (NLO) using the POWHEG method. Computations of the resulting Drell-Yan (DY) transverse momentum spectrum were performed. A good agreement of the theoretical predictions with the measurement performed by the CMS experiment at the center-of-mass energy of 13 TeV is found, at low and intermediate DY $p_{\rm T}$. The new scale choice option for the matching has been included in the CASCADE event generator.

hep-ph↗

arXiv2021

Application of TMD parton showers obtained with the Parton Branching approach to Drell Yan + jets production

Calculations of Drell-Yan (DY) production at next-to-leading (NLO) order have been combined with Transverse Momentum Dependent (TMD) distributions obtained with the Parton Branching (PB). The predictions show a remarkable agreement with DY measurement from E605 experiment, consistent with previous results we obtained for R209, PHENIX, CMS and ATLAS experiments. We also present predictions for Z+jet measurements showing the importance of TMD parton shower contributions to the jet multiplicity. We show that PB-TMD parton density and the corresponding PB-TMD parton shower can be combined with leading-order (LO) matrix element using the newly developed TMD merging algorithm to obtain a very good description of measurements over a wide kinematic range.

hep-ph↗

arXiv2018

$Δϕ$ and multi-jet correlations with CMS

We present angular correlations in multi-jet events at highest center-of-mass energies and compare the measurements to theoretical predictions including higher order parton radiation and coherence effects.

hep-ex↗

arXiv2015

Carbon nanostructures obtained by underwater arc discharge of graphite electrodes: Synthesis and characterization

In the present work, the application of the method of underwater arc discharge of graphite electrodes for obtaining several carbon nanostructures is described. The analysis of the obtained products by Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Raman spectroscopy, Atomic Force Microscopy (AFM) and X-Ray Diffraction (XRD) showed that the samples collected from the material floating on the water surface were composed mainly by polyhedral onion-like particles, while those taken from the precipitate were a mixture multiwalled nano-tubes, onion-like particles and other graphitic structures. The main features of the obtained nanostructures are discussed.

cond-mat.mtrl-sci↗