3. Producción
Browse
111 results
Search Results
- Some of the metrics are blocked by yourconsent settings
Item type:Publication, Reconfiguración de polígonos para determinar la medida de su área con uso del software GeoGebra(Pontifícia Universidade Católica de São Paulo, 2021-12-27)A partir de la operación de reconfiguración que Duval (1994) propone para el cálculo de la medida del área de una figura, este artículo presenta una propuesta para abordar la reconfiguración de figuras bidimensionales mediante el uso del software GeoGebra. Para mostrar la relevancia de la propuesta en la enseñanza de la Geometría, se presenta un estudio con un grupo de alumnos de sexto grado de educación primaria (entre 11 y 12 años). Los resultados muestran el potencial del software para el reconocimiento de figuras con la misma área, el uso de la reconfiguración como operación que permite modificar una figura en otra, el trabajo colaborativo y la motivación hacia las matemáticas. Se concluye que la propuesta es un valioso aporte para la enseñanza de áreas en Geometría. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Síntesis y caracterización de nuevos copolímeros de injerto termosensibles a partir de N-isopropilacrilamida y macromonómeros de 2-metil-2-oxazolina(2021-11-01)Fueron sintetizados nuevos copolímeros injertados a partir de la polimerización por radicales libres de N-isopropilacrilamida (NIPAAm) y macromonómeros de 2-metil-2-oxazolina (MM) iniciada por el 2,2´-azobisisobutironitrilo en dimetilformamida. Los macromonómeros, de grados de polimerización 31 y 62, fueron sintetizados mediante la polimerización catiónica por apertura de anillo de 2-metil-2-oxazolina iniciada por el clorometilestireno en presencia de ioduro de sodio. Los macromonómeros y copolímeros injertados fueron caracterizados por espectrometría de resonancia magnética nuclear de protones (1H-RMN) y la temperatura de transición conformacional fue determinada mediante mediciones turbidimétricas yespectroscopía 1H-RMN.La razón molar NIPAAm/MM en el copolímero, determinada por 1H-RMN, fue mayor que en la alimentación al reactor debido a la mayor reactividad del NIPAAm por su mayor difusividad en el medio reaccionante debido a su menor peso molecular. La temperatura de transición conformacional (LCST) de los copolímeros injertados estuvo en el rango de 33 a 38 °C y la intensidad de la misma fue función de la razón molar de NIPAAm/ macromonómero dentro del copolímero injertado. Se incrementó el valor de la LCST, y al mismo tiempo disminuyó su intensidad, al disminuir la razón molar NIPAAm/MM en el copolímero. La LCST también disminuyó aún más en intensidad al aumentar el grado de polimerización del macromonómero. A partir de la temperatura LCST, los copolímeros injertados con un relativamente alto contenido de MM podrían formar micelas o agregados moleculares tipo “core-shell” en solución acuosa, que estarían formados por un núcleo con segmentos colapsados de poliNIPAAm y una corona formada de cadenas hidrofílicas de polimetiloxazolina, las cuales impiden parcialmente un colapso intermolecular de estos agregados. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Multiharmonic correlations of different flow amplitudes in Pb-Pb collisions at sNN = 2.76 TeV(American Physical Society, 2021-08-27)The event-by-event correlations between three flow amplitudes are measured for the first time in Pb-Pb collisions, using higher-order symmetric cumulants. We find that different three-harmonic correlations develop during the collective evolution of the medium when compared to correlations that exist in the initial state. These new results cannot be interpreted in terms of previous lower-order flow measurements since contributions from two-harmonic correlations are explicitly removed in the new observables. A comparison to Monte Carlo simulations provides new and independent constraints for the initial conditions and system properties of nuclear matter created in heavy-ion collisions. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Measurement of the cross sections of Ξc0 and Ξc+ baryons and of the branching-fraction ratio BR(Ξc0 → Ξ-e+νe)/BR(Ξc0 → Ξ-π+) in pp collisions at s = 13 TeV(American Physical Society, 2021-12-31)The ${p}_{T}$-differential cross sections of prompt charm-strange baryons ${\mathrm{\ensuremath{\Xi}}}_{c}^{0}$ and ${\mathrm{\ensuremath{\Xi}}}_{c}^{+}$ were measured at midrapidity ($|y|<0.5$) in proton-proton ($pp$) collisions at a center-of-mass energy $\sqrt{s}=13\text{ }\text{ }\mathrm{TeV}$ with the ALICE detector at the LHC. The ${\mathrm{\ensuremath{\Xi}}}_{c}^{0}$ baryon was reconstructed via both the semileptonic decay (${\mathrm{\ensuremath{\Xi}}}^{\ensuremath{-}}{e}^{+}{\ensuremath{\nu}}_{e}$) and the hadronic decay (${\mathrm{\ensuremath{\Xi}}}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}$) channels. The ${\mathrm{\ensuremath{\Xi}}}_{c}^{+}$ baryon was reconstructed via the hadronic decay (${\mathrm{\ensuremath{\Xi}}}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{+}$) channel. The branching-fraction ratio $\mathrm{BR}({\mathrm{\ensuremath{\Xi}}}_{c}^{0}\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Xi}}}^{\ensuremath{-}}{e}^{+}{\ensuremath{\nu}}_{e})/\mathrm{BR}({\mathrm{\ensuremath{\Xi}}}_{c}^{0}\ensuremath{\rightarrow}{\mathrm{\ensuremath{\Xi}}}^{\ensuremath{-}}{\ensuremath{\pi}}^{+})=1.38\ifmmode\pm\else\textpm\fi{}0.14(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.22(\mathrm{syst})$ was measured with a total uncertainty reduced by a factor of about 3 with respect to the current world average reported by the Particle Data Group. The transverse momentum (${p}_{T})$ dependence of the ${\mathrm{\ensuremath{\Xi}}}_{c}^{0}$- and ${\mathrm{\ensuremath{\Xi}}}_{c}^{+}$-baryon production relative to the ${D}^{0}$ meson and to the ${\mathrm{\ensuremath{\Sigma}}}_{c}^{0,+,++}$- and ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}$-baryon production are reported. The baryon-to-meson ratio increases toward low ${p}_{T}$ up to a value of approximately 0.3. The measurements are compared with various models that take different hadronization mechanisms into consideration. The results provide stringent constraints to these theoretical calculations and additional evidence that different processes are involved in charm hadronization in electron-positron (${e}^{+}{e}^{\ensuremath{-}}$) and hadronic collisions. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, ΛK femtoscopy in Pb-Pb collisions at sNN = 2.76 TeV(American Physical Society, 2021-05-01)The first measurements of the scattering parameters of $\mathrm{\ensuremath{\Lambda}}K$ pairs in all three charge combinations ($\mathrm{\ensuremath{\Lambda}}{K}^{+}, \mathrm{\ensuremath{\Lambda}}{K}^{\ensuremath{-}}$, and $\mathrm{\ensuremath{\Lambda}}{K}_{S}^{0}$) are presented. The results are achieved through a femtoscopic analysis of $\mathrm{\ensuremath{\Lambda}}K$ correlations in Pb-Pb collisions at $\sqrt{{s}_{NN}}=2.76$ TeV recorded by ALICE at the Large Hadron Collider. The femtoscopic correlations result from strong final-state interactions and are fit with a parametrization allowing for both the characterization of the pair emission source and the measurement of the scattering parameters for the particle pairs. Extensive studies with the THERMINATOR 2 event generator provide a good description of the nonfemtoscopic background, which results mainly from collective effects, with unprecedented precision. Furthermore, together with HIJING simulations, this model is used to account for contributions from residual correlations induced by feed-down from particle decays. The extracted scattering parameters indicate that the strong force is repulsive in the $\mathrm{\ensuremath{\Lambda}}{K}^{+}$ interaction and attractive in the $\mathrm{\ensuremath{\Lambda}}{K}^{\ensuremath{-}}$ interaction. The data hint that the $\mathrm{\ensuremath{\Lambda}}{K}_{S}^{0}$ interaction is attractive; however, the uncertainty of the result does not permit such a decisive conclusion. The results suggest an effect arising either from different quark-antiquark interactions between the pairs ($s\overline{s}$ in $\mathrm{\ensuremath{\Lambda}}{K}^{+}$ and $u\overline{u}$ in $\mathrm{\ensuremath{\Lambda}}{K}^{\ensuremath{-}}$) or from different net strangeness for each system ($S=0$ for $\mathrm{\ensuremath{\Lambda}}{K}^{+}$, and $S=\ensuremath{-}2$ for $\mathrm{\ensuremath{\Lambda}}{K}^{\ensuremath{-}}$). Finally, the $\mathrm{\ensuremath{\Lambda}}K$ systems exhibit source radii larger than expected from extrapolation from identical particle femtoscopic studies. This effect is interpreted as resulting from the separation in space-time of the single-particle $\mathrm{\ensuremath{\Lambda}}$ and $K$ source distributions. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Λc+ production in pp and in p-Pb collisions at sNN = 5.02 TeV(American Physical Society, 2021-11-01)The production cross section of prompt ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}$ charm baryons was measured with the ALICE detector at the LHC at midrapidity in proton-proton ($pp$) and proton-lead ($p\text{--Pb}$) collisions at a center-of-mass energy per nucleon pair of $\sqrt{{s}_{\mathrm{NN}}}=5.02\phantom{\rule{0.16em}{0ex}}\mathrm{TeV}$. The ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}$ and $\overline{\mathrm{\ensuremath{\Lambda}}}{}_{c}^{\ensuremath{-}}$ baryons were reconstructed in the hadronic decay channels ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}\ensuremath{\rightarrow}p{K}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}$ and ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}\ensuremath{\rightarrow}p{K}_{S}^{0}$ and respective charge conjugates. The measured differential cross sections as a function of transverse momentum (${p}_{T}$) and the ${p}_{T}$-integrated ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}$ production cross section in $pp$ and in $p\text{--Pb}$ collisions are presented. The ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}$ nuclear modification factor (${R}_{p\mathrm{Pb}}$), calculated from the cross sections in $pp$ and in $p\text{--Pb}$ collisions, is presented and compared with the ${R}_{p\mathrm{Pb}}$ of $D$ mesons. The ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}/{D}^{0}$ ratio is also presented and compared with the light-flavor baryon-to-meson ratios $p/\ensuremath{\pi}$ and $\mathrm{\ensuremath{\Lambda}}/{K}_{S}^{0}$, and measurements from other LHC experiments. The results are compared to predictions from model calculations and Monte Carlo event generators. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Λc+ production and baryon-to-meson ratios in pp and p-Pb collisions at sNN = 5.02 TeV at the LHC(American Physical Society, 2021-11-12)The prompt production of the charm baryon ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}$ and the ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}/{D}^{0}$ production ratios were measured at midrapidity with the ALICE detector in $pp$ and $p$-Pb collisions at $\sqrt{{s}_{\mathrm{NN}}}=5.02\text{ }\text{ }\mathrm{TeV}$. These new measurements show a clear decrease of the ${\mathrm{\ensuremath{\Lambda}}}_{c}^{+}/{D}^{0}$ ratio with increasing transverse momentum (${p}_{T}$) in both collision systems in the range $2<{p}_{T}<12\text{ }\text{ }\mathrm{GeV}/c$, exhibiting similarities with the light-flavor baryon-to-meson ratios $p/\ensuremath{\pi}$ and $\mathrm{\ensuremath{\Lambda}}/{K}_{S}^{0}$. At low ${p}_{T}$, predictions that include additional color-reconnection mechanisms beyond the leading-color approximation, assume the existence of additional higher-mass charm-baryon states, or include hadronization via coalescence can describe the data, while predictions driven by charm-quark fragmentation processes measured in ${e}^{+}{e}^{\ensuremath{-}}$ and ${e}^{\ensuremath{-}}p$ collisions significantly underestimate the data. The results presented in this Letter provide significant evidence that the established assumption of universality (colliding-system independence) of parton-to-hadron fragmentation is not sufficient to describe charm-baryon production in hadronic collisions at LHC energies. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Searching for solar KDAR with DUNE(IOP Publishing Ltd, 2021-10-01)The observation of 236 MeV muon neutrinos from kaon-decay-at-rest (KDAR) originating in the core of the Sun would provide a unique signature of dark matter annihilation. Since excellent angle and energy reconstruction are necessary to detect this monoenergetic, directional neutrino flux, DUNE with its vast volume and reconstruction capabilities, is a promising candidate for a KDAR neutrino search. In this work, we evaluate the proposed KDAR neutrino search strategies by realistically modeling both neutrino-nucleus interactions and the response of DUNE. We find that, although reconstruction of the neutrino energy and direction is difficult with current techniques in the relevant energy range, the superb energy resolution, angular resolution, and particle identification offered by DUNE can still permit great signal/background discrimination. Moreover, there are non-standard scenarios in which searches at DUNE for KDAR in the Sun can probe dark matter interactions. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Pseudorapidity distributions of charged particles as a function of mid- and forward rapidity multiplicities in pp collisions at √s = 5.02, 7 and 13 TeV(Springer Science and Business Media Deutschland GmbH, 2021-07-01)The multiplicity dependence of the pseudorapidity density of charged particles in proton–proton (pp) collisions at centre-of-mass energies $$\sqrt{s}~=~5.02$$ s = 5.02 , 7 and 13 TeV measured by ALICE is reported. The analysis relies on track segments measured in the midrapidity range ( $$|\eta | < 1.5$$ | η | < 1.5 ). Results are presented for inelastic events having at least one charged particle produced in the pseudorapidity interval $$|\eta |<1$$ | η | < 1 . The multiplicity dependence of the pseudorapidity density of charged particles is measured with mid- and forward rapidity multiplicity estimators, the latter being less affected by autocorrelations. A detailed comparison with predictions from the PYTHIA 8 and EPOS LHC event generators is also presented. The results can be used to constrain models for particle production as a function of multiplicity in pp collisions. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Prospects for beyond the Standard Model physics searches at the Deep Underground Neutrino Experiment: DUNE Collaboration(Springer Science and Business Media Deutschland GmbH, 2021-04-01)The Deep Underground Neutrino Experiment (DUNE) will be a powerful tool for a variety of physics topics. The high-intensity proton beams provide a large neutrino flux, sampled by a near detector system consisting of a combination of capable precision detectors, and by the massive far detector system located deep underground. This configuration sets up DUNE as a machine for discovery, as it enables opportunities not only to perform precision neutrino measurements that may uncover deviations from the present three-flavor mixing paradigm, but also to discover new particles and unveil new interactions and symmetries beyond those predicted in the Standard Model (SM). Of the many potential beyond the Standard Model (BSM) topics DUNE will probe, this paper presents a selection of studies quantifying DUNE’s sensitivities to sterile neutrino mixing, heavy neutral leptons, non-standard interactions, CPT symmetry violation, Lorentz invariance violation, neutrino trident production, dark matter from both beam induced and cosmogenic sources, baryon number violation, and other new physics topics that complement those at high-energy colliders and significantly extend the present reach.