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E. A. Reyes R.

Publications and source records attributed to E. A. Reyes R..

6 recordsLinked to original sources

Rare Higgs Decay into a Photon and a Z Boson in Radiatively-Driven Natural Supersymmetry

In this article, we study the rare decay process in which a Higgs boson decays into a $Z$ boson and a photon. In the first part of the paper, we analyze the Standard Model (SM) contributions to the corresponding decay width, including the full leading-order result, two-loop $O(α_s)$ QCD corrections, and the recently reported two-loop $O(α)$ electroweak corrections, evaluated under four different $α$ renormalization schemes. The dependence on the Higgs boson mass is studied within the experimentally allowed range reported by the LHC. In the considered schemes, a non-negligible variation of about $4\%$ is found when the mass is varied within its current experimental uncertainty. In the second part of the paper, we analyze the leading-order contributions to the same process within the Minimal Supersymmetric Standard Model (MSSM). The spectrum of soft SUSY-breaking parameters and SUSY particle masses at the electroweak scale, which enter the computation of the one-loop amplitudes contributing to the decay width, is obtained by evolving the GUT-scale parameters of a Radiatively-Driven Natural Supersymmetry (RNS) model with non-universal Higgs boson masses. Variations of the RNS parameters can enhance the average SM prediction by up to $\sim20\%$, reaching a value of $\sim7.5~$keV, while still satisfying the Higgs boson mass constraint. However, this comes at the cost of allowing a moderately large fine-tuning parameter, with values exceeding $100$, thereby placing the model outside its most natural parameter region. The predicted decay width in the RNS scenario is closer to the recent ATLAS RUN 2 + 3 combined measurement than the SM expectation.

hep-ph↗

Higgs Boson Mass Corrections at Three-Loops in the Top-Yukawa Sector of the Standard Model

The search for new physics signals in Higgs precision measurements plays a pivotal role in the High-Luminosity Large Hadron Collider (HL-LHC) and future colliders programs. The Higgs properties are expected to be measured with great experimental precision, implying higher-order perturbative computations of the electroweak parameters from the theoretical side. In particular, the renormalized Higgs boson mass parameter in the Standard Model shows significant variation around the electroweak scale, resulting in a lower-bound theoretical uncertainty that exceeds future collider expectations. A more stable result under the renormalization group can be computed from a non-zero external momentum Higgs self-energy, for which available calculations include 3-loop corrections in the QCD sector. In this work, we present an additional contribution by estimating the leading non-QCD 3-loop corrections to the mass of the Higgs boson in the top-Yukawa sector of order $y_t^6$. The momentum-dependent Higgs self-energy is computed in the tadpole-free scheme for the Higgs vacuum expectation value in the Landau gauge, and the explicit dependence upon the Higgs boson and top quark masses is shown. The obtained result is expressed in dimensional regularization as a superposition of a set of master integrals with coefficients that are free of poles in four space-time dimensions, and the corrections are evaluated numerically by the sector decomposition method.

hep-ph↗

High Precision Calculations of the Higgs Boson Mass

In this paper we are going to review the status of the computations of the perturbative quantum corrections to the Higgs boson mass in the Standard Model and in its supersymmetric extensions. In particular, supersymmetric theories require a very accurate computation of the Higgs boson mass, which includes corrections up to even three-loop level, since their predictions are limited by theoretical uncertainties. A discussion about these uncertainties in the context of the minimal and next to minimal supersymmetric standard models is included.

hep-ph↗

A functional approach to the next to eikonal approximation of high energy gravitational scattering

The Fradkin-Schwinger functional methods to represent a Green function in an external gravitational field are used to study the eikonal and the next-to-eikonal limit, including the nonlinear gravitational interactions, of the scattering amplitudes of an ultra-relativistic scalar particle on a static super-massive scalar target in the nearly forward limit. The functional approach confirms the exponentiation of the leading eikonal which also applies to the first non-leading power in the energy of the light particle, moreover includes the interaction at impact parameter much larger than the Schwarzschild radius associated with the center of mass energy in the ultra-relativistic limit.

hep-th↗

Comparison of the EFT Hybrid and Three-Loop Fixed-Order Calculations of the Lightest MSSM Higgs Boson Mass

The lightest Higgs boson mass of the Minimal Supersymmetric Standard Model has been recently computed diagrammatically at the three-loop order in the whole supersymmetric parameters space of the SUSY-QCD sector. The code FeynHiggs combines one- and two-loop fixed-order with the effective-field-theory calculations for the same Higgs mass. The two numerical predictions agree considering the scenario of only one SUSY-scale and vanishing stop mixing parameter below 10 TeV. The agreement is improved by introducing an additional supersymmetric scale and a non-zero stop mixing. Additionally, the combined CMS/ATLAS Higgs mass value was used to derive an upper bound on the needed SUSY scale. In the considered scenario, values above the scale $12.5\pm1.2~\rm{TeV}$ are excluded.

hep-ph↗

The Lightest Higgs Boson Mass of the MSSM at Three-Loop Accuracy

In this article we provide explicit computations of the quantum corrections to the lightest CP-even Higgs Boson mass in the real version of the Minimal Supersymmetric Standard Model. We compute the contributions coming from the SUSY-QCD sector with a precision of three loops at order $O(α_tα_s^2)$. The renormalization procedure adopted is based on the dimensional reduction scheme in order to preserve supersymmetry to all perturbative orders. The calculation extends the region of validity of previous studies to the whole supersymmetric parameter space. The involved master integrals have been computed by exploiting new proposed approaches based on the dispersion relation techniques for the numerical calculation of three-loop vacuum integrals with arbitrary mass scales.

hep-ph↗