Development of Physics learning activities

La utilización de simulaciones y actividades que hacen uso de herramientas informáticas permite integrar los contenidos teóricos y prácticos en actividades atractivas para el alumno. Presentamos varias de estas actividades en asignaturas del grado de Física, pero que pueden adaptarse a asignaturas de otros grados. Se ha observado una mejora en las competencias en el uso de las TICs, así como una mejora en la comprensión de los fenómenos estudiados por parte de los alumnos.The use of simulations and activities including computing tools allows teaching activities integrating both the theoretical and practical aspects of a subject. Some examples are presented for subjects of the Physics Degree. We observed an improvement of the use of computing tools as also a better understanding of the physical phenomena described in these activities

DISTRIBUCIÓN Y ESTADO DE CONSERVACIÓN DEL FARTET, APHANIUS IBERUS (VALENCIENNES, 1846), EN LA REGIÓN DE MURCIA (S.E. DE LA PENÍNSULA IBÉRICA). ESTABLECIMIENTO DE GRUPOS POBLACIONALES OPERATIVOS

Aphanius iberus (= Lebias ibera) is one of the most endangered Iberian vertebrates. It is an endemic fish and its drastic regression for the last two decades has involved the cataloguing of the species into the all national and international Red Listes. Because the area of this study is probably the area where the habitat´s species is most threatened, so the increment in conservation’s efforts on this species is absolutely necessary to secure its perpetuation. As a first step to develop a Recovery Plan for the species in the Murcian region, we have studied its distribution and assessed its conservation status of each locality in which it occurs. For that purpose, we reviewed historical references of the species and sampled all potential sites identified on 1:25000 scale maps using different sampling gears: trawls, fyke nets, minnow traps, hand nets and small bag seines. A.iberus occurred in 40 out of 266 localities visited, 39 localities (9 new records) were included in the Mar Menor coastal lagoon. We also found a new population for the species in the Chicamo Stream (30SXH749368), an isolated population outside of the distribution range known for the species in the Murcian Region. In the study area the regression of A. iberus is clear and coincides with the observed in other areas. Finally, we establish 6 Operational Population Groups (OPGs) as the management units to preserve the species in the Murcian region.Aphanius iberus (= Lebias ibera) es una de las especies de vertebrados ibéricos en mayor peligro de extinción. Su carácter endémico y la drástica regresión que ha sufrido en las dos últimas décadas ha conducido a la catalogación de la especie en todas las listas de especies amenazadas, nacionales e internacionales. El estado de conservación de la especie en el sureste de la Península Ibérica se ha visto deteriorado notablemente. En este sentido, como primer paso para la elaboración del Plan de Recuperación del Fartet en Murcia, se ha establecido la distribución de la especie y el estado de conservación preliminar de las localidades con presencia de la misma. Con esta finalidad han sido estudiadas 266 localidades, para lo que fueron visitadas la totalidad de zonas húmedas, litorales e interiores, con interés para esta especie en la Región de Murcia. Los muestreos fueron realizados con diferentes artes de pesca según las características del cuerpo de agua. A. iberus se presentó en 40 localidades, 39 dentro del área geográfica del Mar Menor y su entorno (9 nuevas citas para la especie). Resalta el hallazgo de una nueva población interior en el río Chícamo (30SXH749368). La regresión de la especie en la Región de Murcia es clara, y coincide con lo observado en otras zonas de la Península. Finalmente, han sido establecidos 6 Grupos Poblacionales Operativos (GPOs) como las unidades de manejo para la adecuada gestión de la especie en la Región de Murcia

ACTUALIZACIÓN DE LA DISTRIBUCIÓN DE LOS ANFIBIOS DE LA REGIÓN DE MURCIA (SE PENÍNSULA IBÉRICA)

We update the distribution of the amphibian community in Murcia Region. During the period 2002-2004, the presence of nine anuran species and one urodele species was detected in the study area. For most of these species, a reduction in their distribution range was registered with regard to previous studies. Water bodies typologies where the reproduction of most amphibian species was detected correspond to artificial pools, the principal threatening factors to these water bodies being modifications in the aquatic environment and the presence of waste products.Se actualiza la distribución de la comunidad de anfibios presente en la Región de Murcia. Durante el período 2002-2004 se detectó la presencia en el área de estudio de nueve especies de anuros y una de urodelo. Para la mayor parte de estas especies ha sido registrada una reducción de sus áreas de distribución respecto a estudios previos. Las tipologías de cuerpo de agua donde se ha constatado la reproducción de la mayor parte de las especies detectadas corresponden a balsas, siendo los principales factores de amenaza a los que están expuestos estos cuerpos de agua la modificación del medio acuático y la presencia de vertidos

Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

This paper presents measurements of the $W^+ \rightarrow \mu^+\nu$ and $W^- \rightarrow \mu^-\nu$ cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

Measurement of χ c1 and χ c2 production with s√ = 7 TeV pp collisions at ATLAS

The prompt and non-prompt production cross-sections for the χ c1 and χ c2 charmonium states are measured in pp collisions at s√ = 7 TeV with the ATLAS detector at the LHC using 4.5 fb−1 of integrated luminosity. The χ c states are reconstructed through the radiative decay χ c → J/ψγ (with J/ψ → μ + μ −) where photons are reconstructed from γ → e + e − conversions. The production rate of the χ c2 state relative to the χ c1 state is measured for prompt and non-prompt χ c as a function of J/ψ transverse momentum. The prompt χ c cross-sections are combined with existing measurements of prompt J/ψ production to derive the fraction of prompt J/ψ produced in feed-down from χ c decays. The fractions of χ c1 and χ c2 produced in b-hadron decays are also measured

Measurement of the production of a W boson in association with a charm quark in pp collisions at √s = 7 TeV with the ATLAS detector

The production of a W boson in association with a single charm quark is studied using 4.6 fb−1 of pp collision data at s√ = 7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96+0.26−0.30 at Q 2 = 1.9 GeV2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio σ(W + +c¯¯)/σ(W − + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the s−s¯¯¯ quark asymmetry

Observation of top-quark pair production in association with a photon and measurement of the ttγ production cross section in pp collisions at √s = 7 TeV using the ATLAS detector

A search is performed for top-quark pairs (tt) produced together with a photon (γ) with transverse energy greater than 20 GeV using a sample of tt candidate events in final states with jets, missing transverse momentum, and one isolated electron or muon. The data set used corresponds to an integrated luminosity of 4.59 fb −1 of proton-proton collisions at a center-of-mass energy of 7 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. In total, 140 and 222 ttγ candidate events are observed in the electron and muon channels, to be compared to the expectation of 79 +/- 26 and 120 +/- 39 non-ttγ background events, respectively. The production of ttγ events is observed with a significance of 5.3 standard deviations away from the null hypothesis. The ttγ production cross section times the branching ratio (BR) of the single-lepton decay channel is measured in a fiducial kinematic region within the ATLAS acceptance. The measured value is σ (fid/tty) × BR = 63 +/- 8(stat) (+17/-13)(syst) +/- 1 lumi fb per lepton flavor, in good agreement with the leading-order theoretical calculation normalized to the next-to-leading-order theoretical prediction of 48 +/- 10 fb

Search for a CP-odd Higgs boson decaying to Zh in pp collisions at √s=8TeV with the ATLAS detector

A search for a heavy, CP-odd Higgs boson, A, decaying into a Zboson and a 125GeV Higgs boson, h, with the ATLAS detector at the LHC is presented. The search uses proton–proton collision data at a centre-of-mass energy of 8TeV corresponding to an integrated luminosity of 20.3fb−1. Decays of CP-even hbosons to ττor bbpairs with the Zboson decaying to electron or muon pairs are considered, as well as h →bbdecays with the Zboson decaying to neutrinos. No evidence for the production of an Aboson in these channels is found and the 95% confidence level upper limits derived for σ(gg→A) ×BR(A →Zh) ×BR(h →f¯f)are 0.098–0.013pb for f=τand 0.57–0.014pb for f=bin a range of mA=220–1000GeV. The results are combined and interpreted in the context of two-Higgs-doublet models. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 8 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three leptons and missing transverse momentum is presented. The analysis is based on 20.3 fb−1 of s√ = 8 TeV proton-proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with the Standard Model expectations and limits are set in R-parity-conserving phenomenological Minimal Supersymmetric Standard Models and in simplified supersymmetric models, significantly extending previous results. For simplified supersymmetric models of direct chargino (χ˜±1) and next-to-lightest neutralino (χ˜02) production with decays to lightest neutralino (χ˜01) via either all three generations of sleptons, staus only, gauge bosons, or Higgs bosons, (χ˜±1) and (χ˜02) masses are excluded up to 700 GeV, 380 GeV, 345 GeV, or 148 GeV respectively, for a massless (χ˜01

Search for narrow resonances in dilepton mass spectra in proton-proton collisions at root s=13 TeV and combination with 8 TeV data

Peer reviewe