Gravitational Coleman-Weinberg mechanism

The Coleman-Weinberg mechanism provides a procedure by which a scalar field, which initially has no mass parameters, acquires a mass due to the anomalous nature of scale symmetry. Loop corrections trigger a spontaneous symmetry breaking and the appearance of a non-trivial vacuum. We first review the basic example of the Coleman-Weinberg mechanism, scalar Quantum Electrodynamics, in a perturbative regime where the scalar particle becomes massive through photon loops. We then present the main results of this article, what we name the gravitational Coleman-Weinberg mechanism: we analyse the same effect in a gravitational theory without explicit energy scales at tree-level. Finally, we also study the mechanism for two scalar fields in the mentioned gravitational theory. We will derive the gravitational Coleman-Weinberg potentials, analyse the parameter space where we have a symmetry breaking, and obtain the value of the corresponding scalar masses

Estrategias para la implementación de Sistemas de Gestión de Seguridad y Salud en el Trabajo en las empresas del sector industrial. Revisión narrativa de la literatura

Introduction. The fast pace of the industries has generated the need to implement and maintain occupational health and safety management systems in an optimal way, through strategies that improve the level of production, competitiveness and labor well-being. Objective. To identify the different strategies used by companies in the industrial sector to implement occupational health and safety management systems. Methodology. A narrative review of the literature, with research published from January 2016 to February 2022, in electronic databases ProQuest, Scielo, ISUB, Dialnet, Lilacs and university repositories, Spanish and English, including different designs, strategies of implementation, standards and policies applied to create management systems in Safety and Health at Work in the industrial sector. 36 documents that met the inclusion and exclusion criteria were obtained. Results.  The most applied strategies started from the implementation of the plan-do-verify-act cycle through semi-structured interviews and observation of the work environment, revealing the levels of risk prevention and activities for them. Conclusion. It is important to highlight that not all companies have mechanisms to generate risk assessment aimed at meeting institutional objectives. Likewise, there are institutions that, through strategies such as surveys, questionnaires, observation measures, checklists, seek to create an analysis and risk assessment to implement management systems in the organization's work environment.Introducción. El acelerado ritmo de las industrias ha generado la necesidad de implementar y mantener sistemas de gestión en seguridad y salud en el trabajo de manera óptima, a través de estrategias que mejoren el nivel de producción, competitividad y bienestar laboral.  Objetivo. Identificar las diferentes estrategias que utilizan las empresas del sector industrial para implementar sistemas de gestión de Seguridad y Salud en el Trabajo. Metodología. Revisión narrativa de la literatura, con investigaciones publicadas de enero de 2016 a febrero de 2022, en bases de datos electrónicas ProQuest, Scielo, ISUB, Dialnet, Lilacs y repositorios universitarios, idioma español e inglés, que incluyeran diferentes diseños, estrategias de implementación, normas y políticas aplicadas para crear sistemas de gestión en Seguridad y Salud en el Trabajo en el sector industrial. Se obtuvieron 36 documentos que cumplían criterios de inclusión y exclusión. Resultados. Las estrategias más aplicadas partieron de la implementación del ciclo planificar-hacer-verificar-actuar a través de entrevistas semiestructuradas y observación del entorno laboral, dando a conocer los niveles de prevención de riesgos y actividades para los mismos. Conclusión. Es importante resaltar que no todas las empresas cuentan con mecanismos para generar la evaluación de riesgos encaminados al cumplimiento de objetivos institucionales.  Así mismo, existen instituciones que, a través de estrategias como encuestas, cuestionarios, medidas de observación, listas de chequeo, buscan crear un análisis y evaluación de riesgos para implementar sistemas de gestión en el entorno laboral de la organización

Física, Matemáticas y Música

Esta documento corresponde a la memoria final de ejecución del proyecto de innovación docente número 210 de la convocatoria 2020/2021 que lleva por título "Física, Matemáticos y Música"

Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at root s=13 TeV

A search is presented for new particles produced at the LHC in proton-proton collisions at root s = 13 TeV, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb(-1), collected in 2017-2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb(-1), collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.Peer reviewe

MUSiC : a model-unspecific search for new physics in proton-proton collisions at root s=13TeV

Results of the Model Unspecific Search in CMS (MUSiC), using proton-proton collision data recorded at the LHC at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb(-1), are presented. The MUSiC analysis searches for anomalies that could be signatures of physics beyond the standard model. The analysis is based on the comparison of observed data with the standard model prediction, as determined from simulation, in several hundred final states and multiple kinematic distributions. Events containing at least one electron or muon are classified based on their final state topology, and an automated search algorithm surveys the observed data for deviations from the prediction. The sensitivity of the search is validated using multiple methods. No significant deviations from the predictions have been observed. For a wide range of final state topologies, agreement is found between the data and the standard model simulation. This analysis complements dedicated search analyses by significantly expanding the range of final states covered using a model independent approach with the largest data set to date to probe phase space regions beyond the reach of previous general searches.Peer reviewe

Measurement of prompt open-charm production cross sections in proton-proton collisions at root s=13 TeV

The production cross sections for prompt open-charm mesons in proton-proton collisions at a center-of-mass energy of 13TeV are reported. The measurement is performed using a data sample collected by the CMS experiment corresponding to an integrated luminosity of 29 nb(-1). The differential production cross sections of the D*(+/-), D-+/-, and D-0 ((D) over bar (0)) mesons are presented in ranges of transverse momentum and pseudorapidity 4 < p(T) < 100 GeV and vertical bar eta vertical bar < 2.1, respectively. The results are compared to several theoretical calculations and to previous measurements.Peer reviewe

Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at root s=13 TeV

A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 137 fb(-1) collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on themodel, the combined result excludes a top squarkmass up to 1325 GeV for amassless neutralino, and a neutralinomass up to 700 GeV for a top squarkmass of 1150 GeV. Top squarks with masses from 145 to 295 GeV, for neutralino masses from 0 to 100 GeV, with a mass difference between the top squark and the neutralino in a window of 30 GeV around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420 GeV

Measurement of the azimuthal anisotropy of Y(1S) and Y(2S) mesons in PbPb collisions at root s(NN)=5.02 TeV

The second-order Fourier coefficients (v(2)) characterizing the azimuthal distributions of Y(1S) and Y(2S) mesons produced in PbPb collisions at root s(NN) = 5.02 TeV are studied. The Y mesons are reconstructed in their dimuon decay channel, as measured by the CMS detector. The collected data set corresponds to an integrated luminosity of 1.7 nb(-1). The scalar product method is used to extract the v2 coefficients of the azimuthal distributions. Results are reported for the rapidity range vertical bar y vertical bar < 2.4, in the transverse momentum interval 0 < pT < 50 GeV/c, and in three centrality ranges of 10-30%, 30-50% and 50-90%. In contrast to the J/psi mesons, the measured v(2) values for the Y mesons are found to be consistent with zero. (C) 2021 The Author(s). Published by Elsevier B.V.Peer reviewe