Astrobiochronology of Late Neogene deposits near the Strait of Gibraltar (SW Spain). Implications for the tectonic control of the Messinian Salinity Crisis

[EN]The main objective of this work is to explore the Guadalquivir basin and the Gulf of Cadiz to obtain continuous sediment records for the interval of the Messinian Salinity Crisis on the Atlantic side of the Iberian peninsula so as to analyse the possible paleoenvironmental, tectonic or paleoclimatic changes in a region which was only a few kms away from the Mediterranean coasts during this time period

Early Pliocene climatic optimum, cooling and early glaciation deduced by terrestrial and marine environmental changes in SW Spain

The Pliocene is a key period in Earth's climate evolution, as it records the transition from warm and stable conditions to the colder and more variable glaciated climate of the Pleistocene. Simultaneously, climate became more seasonal in the Mediterranean area, and Mediterranean-type seasonal precipitation rhythm with summer drought established. These climatic changes presumably had significant impacts on terrestrial environments. However, the response of terrestrial environments to such climate changes is still not fully understood due to the lack of detailed studies dealing with this period of time. In this study, multiproxy analyses of continuous core sampling from La Matilla (SW Spain) shows detailed and continuous record of pollen, sand content and abundance of benthic foraminifer Bolivina spathulata to describe paleoenvironmental and paleoclimate trends during the early Pliocene. This record shows warmest, most humid climate conditions and highest riverine nutrient supply at ~ 4.35 Ma, coinciding with the Pliocene climatic optimum and high global sea level. A climate cooling and aridity trend occurred subsequently and a significant glaciation occurred at ~ 4.1–4.0 Ma, during a period known by very little terrestrial evidence of glaciation. Our multiproxy data thus indicate that terrestrial and marine environments were significantly variable during the early Pliocene and that major glaciation-like cooling occurred before the intensification of northern hemisphere glaciation at the beginning of the Pleistocene (~2.7 Ma). This major climate cooling and aridity maxima between 4.1 and 4.0 Ma is independently validated by a coeval sea-level drop (third order Za2 sequence boundary). This sea level drawdown is supported by enhanced coarse sedimentation and minima in riverine nutrient supply, showing paired vegetation and sea-level changes and thus a strong land-ocean relationship. This study also shows that long-term climatic trends were interrupted by orbital-scale cyclic climatic variability, with eccentricity, obliquity and precession acting as the main triggers controlling climate and environmental change in the area.Peer ReviewedPostprint (author's final draft

Astrobiocronología y estratigrafía de alta resolución del neógeno de la cuenca del Guadalquivir-golfo de Cádiz

[ES] Se presenta una detallada cronológica del Neógeno de la cuenca del Guadalquivir-Golfo de Cadiz basada en 20 bioeventos de plancton calcáreo, y se proponen seis unidades bioestratigráficas. Se presente asimismo la datación individual de los aparatos turbidíticos messinienses objeto de la exploración de hidrocarburos. Se han utilizado 32 sondeos en el analisis bioestratigrafico. El reconocimiento en las diagrafias de las pautas de ciclicidad astronomica (frecuencias de Milankovitch) ha permitido correlacionar ciclo a ciclo 20 diagrafias (de rayos gamma, velocidad sónica y resistividad), con la curva de insolación de verano (Laskar, 1990) y la escala astronomica de tiempo. Asimismo se muestra una correlación capa a capa con las secciones de referencia de la cuenca de Sorbas (Almeria) y de Capo Rossello (Sicilia). Se establecen una serie de unidades cicloestratigraficas de carácter astronomico-climatico datando y correlacionando el intervalo de 7.5 Ma hasta 2.6 Ma. Esta tesis trata de demostrar como el analisis cicloestratigrafico del registro geofisico, acompañado de estudios bioestratigrafivos permite correlaciones globales y dataciones astronomicas con errores inferiores a 20 ka. Se han identificado cinco unidades litosismicas desde el Tortoniense superior basadas en 11 perfiles de tipo sismobioestratigrafico, estableciendose la relacion de estas unidades con la secuencia de relleno de la cuenca. El contexto tectónico compresivo entorno al limite Tortoniense-Messiniense, pudo desencadenar el ingreso de olistotroma, el desarrollo de los cuerpos turbiditicos messinienses en el Guadalquivir y el cierre definitivo de la conexión Atlántico-Mediterraneo en el estrecho Norbetico. El desarrollo de los aparatos turbiditicos en el fondo de cuenca se prolongaria durante todo el Messiniense. En el limite Mio-Plioceno, se produce una inversión de las condiciones tectonicas

Early Pliocene climatic optimum, cooling and early glaciation deduced by terrestrial and marine environmental changes in SW Spain

This article is subject to a Creative Commons Attribution Non-Commercial No Derivatives LicenseThe Pliocene is a key period in Earth's climate evolution, as it records the transition from warm and stable conditions to the colder and more variable glaciated climate of the Pleistocene. Simultaneously, climate became more seasonal in the Mediterranean area, and Mediterranean-type seasonal precipitation rhythm with summer drought established. These climatic changes presumably had significant impacts on terrestrial environments. However, the response of terrestrial environments to such climate changes is still not fully understood due to the lack of detailed studies dealing with this period of time. In this study, multiproxy analyses of continuous core sampling from La Matilla (SW Spain) shows detailed and continuous record of pollen, sand content and abundance of benthic foraminifer Bolivina spathulata to describe paleoenvironmental and paleoclimate trends during the early Pliocene. This record shows warmest, most humid climate conditions and highest riverine nutrient supply at ~ 4.35 Ma, coinciding with the Pliocene climatic optimum and high global sea level. A climate cooling and aridity trend occurred subsequently and a significant glaciation occurred at ~ 4.1–4.0 Ma, during a period known by very little terrestrial evidence of glaciation. Our multiproxy data thus indicate that terrestrial and marine environments were significantly variable during the early Pliocene and that major glaciation-like cooling occurred before the intensification of northern hemisphere glaciation at the beginning of the Pleistocene (~2.7 Ma). This major climate cooling and aridity maxima between 4.1 and 4.0 Ma is independently validated by a coeval sea-level drop (third order Za2 sequence boundary). This sea level drawdown is supported by enhanced coarse sedimentation and minima in riverine nutrient supply, showing paired vegetation and sea-level changes and thus a strong land-ocean relationship. This study also shows that long-term climatic trends were interrupted by orbital-scale cyclic climatic variability, with eccentricity, obliquity and precession acting as the main triggers controlling climate and environmental change in the area. © 2019 Elsevier B.V.This study was supported by the research projects CGL2012-30875 (GUADALTYC), CGL2013-47038-R, CGL-2017-85415-R and CGL2014-59516 (MITE) of the Ministerio de Economía y Competitividad of Spain, project P11-RNM-7332 from the Junta de Andalucía, and the Research Groups RNM-190 of the Junta de Andalucía and GRC Geociències Marines (2017 SGR 315) of the Generalitat de Catalunya.Peer reviewe

Teachers' network and digital repository of educational resources: A history of contemporary capitalism I. The crisis of the liberal State and the first globalization through filmic, literary and aesthetic sources.

Se trata de crear un repositorio digital de apoyo a la docencia virtual, con contribuciones innovadoras en el empleo de fuentes artísticas y culturales para el estudio de la crisis del Estado liberal y de la primera globalización (1920-1930).This project aims to create a digital repository to support virtual teaching, with innovative contributions in the use of artistic and cultural sources for the study of the crisis of the liberal State and the first globalization (1920-1930).Depto. de Filosofía y SociedadFac. de FilosofíaFALSEUCMsubmitte

Extracting the speed of sound in the strongly interacting matter created in ultrarelativistic lead-lead collisions at the LHC

International audienceUltrarelativistic nuclear collisions create a strongly interacting state of hot and dense quark-gluon matter that exhibits a remarkable collective flow behavior with minimal viscous dissipation. To gain deeper insights into its intrinsic nature and fundamental degrees of freedom, we extracted the speed of sound in this medium created using lead-lead (PbPb) collisions at a center-of-mass energy per nucleon pair of 5.02 TeV. The data were recorded by the CMS experiment at the CERN LHC and correspond to an integrated luminosity of 0.607 nb$^{-1}$. The measurement is performed by studying the multiplicity dependence of the average transverse momentum of charged particles emitted in head-on PbPb collisions. Our findings reveal that the speed of sound in this matter is nearly half the speed of light, with a squared value of 0.241 $\pm$ 0.002 (stat) $\pm$ 0.016 (syst) in natural units. The effective medium temperature, estimated using the mean transverse momentum, is 219 $\pm$ 8 (syst) MeV. The measured squared speed of sound at this temperature aligns precisely with predictions from lattice quantum chromodynamic (QCD) calculations. This result provides a stringent constraint on the equation of state of the created medium and direct evidence for a deconfined QCD phase being attained in relativistic nuclear collisions

Elliptic anisotropy measurement of the f0_0(980) hadron in proton-lead collisions and evidence for its quark-antiquark composition

International audienceDespite the f$_0$(980) hadron having been discovered half a century ago, the question about its quark content has not been settled: it might be an ordinary quark-antiquark ($\mathrm{q\bar{q}}$) meson, a tetraquark ($\mathrm{q\bar{q}q\bar{q}}$) exotic state, a kaon-antikaon ($\mathrm{K\bar{K}}$) molecule, or a quark-antiquark-gluon ($\mathrm{q\bar{q}g}$) hybrid. This paper reports strong evidence that the f$_0$(980) state is an ordinary $\mathrm{q\bar{q}}$ meson, inferred from the scaling of elliptic anisotropies ($v_2$) with the number of constituent quarks ($n_\mathrm{q}$), as empirically established using conventional hadrons in relativistic heavy ion collisions. The f$_0$(980) state is reconstructed via its dominant decay channel f$_0$(980) $\to$$\pi^+\pi^-$, in proton-lead collisions recorded by the CMS experiment at the LHC, and its $v_2$ is measured as a function of transverse momentum ($p_\mathrm{T}$). It is found that the $n_q$ = 2 ($\mathrm{q\bar{q}}$ state) hypothesis is favored over $n_q$ = 4 ($\mathrm{q\bar{q}q\bar{q}}$ or $\mathrm{K\bar{K}}$ states) by 7.7, 6.3, or 3.1 standard deviations in the $p_\mathrm{T}$$\lt$ 10, 8, or 6 GeV/$c$ ranges, respectively, and over $n_\mathrm{q}$ = 3 ($\mathrm{q\bar{q}g}$ hybrid state) by 3.5 standard deviations in the $p_\mathrm{T}$$\lt$ 8 GeV/$c$ range. This result represents the first determination of the quark content of the f$_0$(980) state, made possible by using a novel approach, and paves the way for similar studies of other exotic hadron candidates

Extracting the speed of sound in the strongly interacting matter created in ultrarelativistic lead-lead collisions at the LHC

International audienceUltrarelativistic nuclear collisions create a strongly interacting state of hot and dense quark-gluon matter that exhibits a remarkable collective flow behavior with minimal viscous dissipation. To gain deeper insights into its intrinsic nature and fundamental degrees of freedom, we extracted the speed of sound in this medium created using lead-lead (PbPb) collisions at a center-of-mass energy per nucleon pair of 5.02 TeV. The data were recorded by the CMS experiment at the CERN LHC and correspond to an integrated luminosity of 0.607 nb$^{-1}$. The measurement is performed by studying the multiplicity dependence of the average transverse momentum of charged particles emitted in head-on PbPb collisions. Our findings reveal that the speed of sound in this matter is nearly half the speed of light, with a squared value of 0.241 $\pm$ 0.002 (stat) $\pm$ 0.016 (syst) in natural units. The effective medium temperature, estimated using the mean transverse momentum, is 219 $\pm$ 8 (syst) MeV. The measured squared speed of sound at this temperature aligns precisely with predictions from lattice quantum chromodynamic (QCD) calculations. This result provides a stringent constraint on the equation of state of the created medium and direct evidence for a deconfined QCD phase being attained in relativistic nuclear collisions

Search for long-lived heavy neutral leptons with lepton flavour conserving or violating decays to a jet and a charged lepton

International audienceA search for long-lived heavy neutral leptons (HNLs) is presented, which considers the hadronic final state and coupling scenarios involving all three lepton generations in the 2-20 GeV HNL mass range for the first time. Events comprising two leptons (electrons or muons) and jets are analyzed in a data sample of proton-proton collisions, recorded with the CMS experiment at the CERN LHC at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb$^{-1}$. A novel jet tagger, based on a deep neural network, has been developed to identify jets from an HNL decay using various features of the jet and its constituent particles. The network output can be used as a powerful discriminating tool to probe a broad range of HNL lifetimes and masses. Contributions from background processes are determined from data. No excess of events in data over the expected background is observed. Upper limits on the HNL production cross section are derived as functions of the HNL mass and the three coupling strengths $V_{\ell\mathrm{N}}$ to each lepton generation $\ell$ and presented as exclusion limits in the coupling-mass plane, as lower limits on the HNL lifetime, and on the HNL mass. In this search, the most stringent limit on the coupling strength is obtained for pure muon coupling scenarios; values of $\lvert V_{\mu\mathrm{N}}\rvert^{2}\gt$ 5 (4)$\times$10$^{-7}$ are excluded for Dirac (Majorana) HNLs with a mass of 10 GeV at a confidence level of 95% that correspond to proper decay lengths of 17 (10) mm