Universidad Iberoamericana Ciudad de México

About: Universidad Iberoamericana Ciudad de México is a education organization based out in Mexico City, Mexico. It is known for research contribution in the topics: Large Hadron Collider & Standard Model. The organization has 2259 authors who have published 3981 publications receiving 109298 citations.

Formation and growth of water-in-CO2 miniemulsions

Abstract: We report nonflocculated dilute water-in-CO2 (W/C) miniemulsions stable for 24 h in contrast with flocculated unstable macroemulsions reported previously. The surfactants, poly(1,1-dihydroperfluorooctyl methacrylate)-b-poly(ethylene oxide) (PFOMA-b-PEO), were synthesized by atom transfer radical polymerization to achieve the proper hydrophilic−CO2-philic balance (HCB) and a low interfacial tension (∼0.2−2 mN/m) between water and CO2. The average particle diameter, ranging from 70 to 140 nm, was measured with multiwavelength turbidimetry utilizing Mie theory, and the interfacial tension was measured with high pressure pendant drop tensiometry. Because flocculation and coalescence were suppressed nearly completely, it became feasible to investigate emulsion droplet formation and droplet growth by Ostwald ripening. Droplet formation was characterized as a function of the mechanical energy at various CO2 densities and temperatures and was correlated quantitatively to the interfacial tensions. The molar water/...

Sourcing Pandemic News: A Cross-National Computational Analysis of Mainstream Media Coverage of COVID-19 on Facebook, Twitter, and Instagram

Abstract: This article explores the uses of sources in coverage of the COVID-19 pandemic in social media posts of mainstream news organizations in Brazil, Chile, Germany, Mexico, Spain, the U.K., and the U.S...

Search for new bottomlike quark pair decays QQ̄→(tW) (t̄W ± ) in same-charge dilepton events

Abstract: We report the most restrictive direct limits on masses of fourth-generation down-type quarks b{sup '}, and quarklike composite fermions (B or T{sub 5/3}), decaying promptly to tW{sup +}-. We search for a significant excess of events with two same-charge leptons (e, mu), several hadronic jets, and missing transverse energy. An analysis of data from pp collisions with an integrated luminosity of 2.7 fb{sup -1} collected with the CDF II detector at Fermilab yields no evidence for such a signal, setting mass limits m{sub b}{sup '}, m{sub B}>338 GeV/c{sup 2} and m{sub T{sub 5{sub /{sub 3}}}}>365 GeV/c{sup 2} at 95% confidence level.

Search for a singly produced third-generation scalar leptoquark decaying to a τ lepton and a bottom quark in proton-proton collisions at s√=13 TeV

Abstract: A search is presented for a singly produced third-generation scalar leptoquark decaying to a τ lepton and a bottom quark. Associated production of a leptoquark and a τ lepton is considered, leading to a final state with a bottom quark and two τ leptons. The search uses proton-proton collision data at a center-of-mass energy of 13 TeV recorded with the CMS detector, corresponding to an integrated luminosity of 35.9 fb−1. Upper limits are set at 95% confidence level on the production cross section of the third-generation scalar leptoquarks as a function of their mass. From a comparison of the results with the theoretical predictions, a third-generation scalar leptoquark decaying to a τ lepton and a bottom quark, assuming unit Yukawa coupling (λ), is excluded for masses below 740 GeV. Limits are also set on λ of the hypothesized leptoquark as a function of its mass. Above λ = 1.4, this result provides the best upper limit on the mass of a third-generation scalar leptoquark decaying to a τ lepton and a bottom quark.