Found 60 talks archived in Particle astrophysics, physical data and processes

antonio_garcia_munoz_090305s
Sunday May 3, 2009
Dr. Antonio García Muñoz
Instituto de Astrofísica de Canarias, Spain

Abstract

There is a multitude of photochemical processes occurring in a planet's atmosphere. Some of these processes occur with an excess of energy and lead to products in the form of excited atoms, molecules and ions.In specific cases, these gases radiate at wavelengths that range from the UV to the NIR. Solar light is the ultimate cause of these airglow emissions, but traditionally one distinguishes between the day airglow (dayglow), and the night airglow (nightglow). The contribution of the Sun to the excitation of the emitting gas is more immediate in the day glow than in the nightglow. The airglow makes it possible to remotely investigate the chemical kinetics, energetic balance and dynamics of a planetary atmosphere. In the talk, I will go over some of the air glow missions that are known to exist in the atmospheres of the Earth, Mars and Venus. The examples illustrate some of my recent work, and include theoretical modelling and the interpretation of observational data. There is a long record of contributions to the nightglow from observations carried out at ground-based telescopes. I will briefly comment some of these.

sebastian_xambo_090326s
Thursday March 26, 2009
Prof. Sebastiá Xambó
Universidad Politécnica de Cataluña, Spain

Abstract

En una parte preliminar se recordarán unos pocos hechos experimentales obtenidos durante las últimas décadas, con énfasis en fenómenos puramente cuánticos como el entrelazamiento y el teletransporte, y también algunos hechos matemáticos elementales, con énfasis en las matrices hermíticas y unitarias. En una segunda parte se presentará un modelo matemático de la noción de q-ordenador y de conceptos subordinados como puertas q-lógicas, q-computación y q-algoritmos programas, con énfasis en los ejemplos, incluyendo la q-transformada de Fourier y el q-algoritmo de Shor de factorización en tiempo polinómico de números enteros positivos. A continuación se sumarizará un enfoque axiomático de la mecánica cuántica y se usará para relacionar las q-nociones anteriores con sus posibles realizaciones físicas, con énfasis en algunos problemas abiertos y en posibles líneas de trabajo futuro. La base de este material es la tesis de máster de Juanjo Rué,  "Un modelo matemático para la computación cuántica: fundamentos, algoritmos y aplicaciones" (julio de 2007), dirigida por Lluís Torner y el conferenciante.


ana_chies_santos_090318s
Wednesday March 18, 2009
Dr. Ana Chies Santos
Astronomical Institute Utrecht, the Netherlands

Abstract

The colour distribution of globular cluster (GC) systems in the majority of galaxies is bi/multimodal in optical colours. It is widely accepted that multiple populations differing in metallicity exist implying different mechanisms/epochs of star formation, with small age differences still being allowed due to the large current uncertainties. Recently Yoon, Yi and Lee (2006) challenged this interpretation stating that the metallicity bimodality is an artifact of the horizontal branch (HB) morphologies that can transform a unimodal metallicity distribution in a bimodal (optical) colour distribution. The combination of optical and near-infrared (NIR) colours can in principal break the age/metallicity degeneracy inherent in optical colours alone, allowing age estimates for a large sample of GCs possible at the same time. It has been shown that the colours that best represent the true metallicity distributions are the combination of optical and NIR (eg. Puzia et al. 2002, Cantiello & Blakeslee 2007). Therefore studying GCs in the NIR is crucial to reveal their true metallicity distributions. We are currently building a homogeneous optical/NIR data set of GC systems in a large sample of elliptical and lenticular galaxies. I will present the sample, an attempt to estimate overall ages and metallicities for the GC systems and the optical/NIR colour distributions.

valentina_luridiana_081127s
Thursday November 27, 2008
Dr. Valentina Luridiana
Instituto de Astrofísica de Andalucía, Spain

Abstract

Primordial helium might seem to be just a tiny piece in our understanding of how the Universe was born; still, it is a piece that must fit in if we are to ensure that the whole Big Bang scenario is consistent. During the last decade, a significant effort has been aimed at achieving the necessary accuracy to achieve this goal. While we still do not have a firm handle on it, we have learned quite a few things on the way. The talk will provide a review of this quest, highlighting the uncertainties that still remain and the feedback that it has provided to our knowledge of how H II regions work.

lee_spitler_081117s
Monday November 17, 2008
Dr. Lee Spitler
Swinburne University, Australia

Abstract

In the Λ-CDM galaxy formation paradigm, the star formation history of a galaxy is coupled to the total mass of its dark matter halo through processes like galaxy-galaxy merging, satellite accretion, and gas retention. Globular cluster formation is known to coincide with strong star formation events in the early Universe. To develop an accurate model of galaxy formation, the relationship between such systems and their hosting dark matter halos must be understood. Employing weak gravitational lensing galaxy mass analysis, we have discovered that the number of globular clusters in a given galaxy is directly proportional to its total dark matter halo mass. This result holds in both dwarf and giant ellipticals, spirals and in all types of galaxy environments. I will present these observations and initiate a discussion on the implications for scenarios of globular cluster system formation and evolution.


fernando_cornet_081106s
Thursday November 6, 2008
Prof. Fernando Cornet
Universidad de Granada, Spain

Abstract

Las clases se impartirán en el aula los días 4, 5 y 6 de noviembre de 2008 en horario de 10:30 a 12:30 Programa del curso: 1.- Introduction 2.- Electromagnetic Interaction (QED) 3.- Strong Interaction (QCD) 4.- Electroweak Interaction 5.- Precision Tests 6.- CP Violation and B Physics 7.- Neutrino Masses 8.- Beyond the Standard Model 9.- Physics at LHC


fernando_cornet_081105s
Wednesday November 5, 2008
Prof. Fernando Cornet
University of Granada, Spain

Abstract

Programa del curso: 1.- Introduction 2.- Electromagnetic Interaction (QED) 3.- Strong Interaction (QCD) 4.- Electroweak Interaction 5.- Precision Tests 6.- CP Violation and B Physics 7.- Neutrino Masses 8.- Beyond the Standard Model 9.- Physics at LHC


fernando_cornet_081104s
Tuesday November 4, 2008
Prof. Fernando Cornet
University of Granada, Spain

Abstract

Programa del curso: 1.- Introduction 2.- Electromagnetic Interaction (QED) 3.- Strong Interaction (QCD) 4.- Electroweak Interaction 5.- Precision Tests 6.- CP Violation and B Physics 7.- Neutrino Masses 8.- Beyond the Standard Model 9.- Physics at LHC


bc_low_080605s
Thursday June 5, 2008
Prof. Boon-Chye Low
High Altitude Observatory, National Center for Atmospheric Research, USA

Abstract

A continuous magnetic field evolving under the hydromagnetic frozen-in condition preserves its field topology. Depending on that field topology, the evolving field may inevitably develop electric current-sheets, i.e., magnetic tangential discontinuities, in the course of nonlinear fluid-field interaction. This inevitability obtains for all field topologies one could prescribe for the field, except those of a special subset of measure zero. This theory of Eugene Parker is based on demonstrating that a field endowed with a fixed topology cannot generally find an equilibrium state in which the field is everywhere spatially continuous. I will discuss a recent development of this magnetostatic problem from an intuitive point of view, giving a basic understanding of why current sheets not only form easily but do so throughout a magnetic field. Parker’s theory explains the heating of the solar corona, to million-degree temperatures, in terms of spontaneous current sheets that must form because of high electrical conductivity, and, yet, must dissipate in spite of that high (but finite) conductivity. This process may be the fundamental reason for the high-temperature plasmas found almost everywhere in the astrophysical universe


hans_ludwig_080429s
Tuesday April 29, 2008
Prof. Hans-G. Ludwig
Observatoire de Paris-Meudon, France

Abstract

In the EU funded Marie Curie Excellence Team CIFIST (Cosmological Impact of the FIrst STars) work is under way to construct 3D radiation-hydrodynamical model atmospheres for late-type dwarfs and giants, in particular of low metallicity. I will present an overview of the present state of the efforts, discuss some applications of the models, and point to necessary future developments.


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