Found 3 talks width keyword Galactic center

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Thursday May 13, 2021
Prof. Diego Blas
Imperial College

Abstract

Bosonic ultra-light dark matter (ULDM) in the mass range m ~ $10^{-22} - 10^{-21} \rm eV$ has been invoked as a motivated candidate with new input for the small-scale `puzzles' of cold dark matter. Numerical simulations show that these models form cored density distributions at the center of galaxies ('solitons'). These works also found an empirical scaling relation between the mass of the large-scale host halo and the mass of the central soliton. We show that this relation predicts that the peak circular velocity of the outskirts of the galaxy should approximately repeat itself in the central region. Contrasting this prediction to the measured rotation curves of well-resolved near-by galaxies, we show that ULDM in the mass range m ~ $10^{-22} - 10^{-21} \rm eV$ is in tension with the data.


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Thursday April 19, 2012
Dr. Carlos González Fernández
Universidad de Alicante, Spain

Abstract

Abstract: The study of the structure of our Galaxy, particularly its inner disc, has always been hindered by two factors: interstellar extinction dims even the brightest stars at optical wavelengths and the high source density prevents us, as the proverbial trees, to see the big galactic picture. 

With this talk we give a broad introduction of the historical efforts to alleviate these issues in the neverending quest to dig deeper into the Milky Way, followed by a overview of the first results obtained by the VVV-Vista survey, that maps the southern Galactic sky with unprecedent depth and resolution.

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Thursday March 18, 2010
Prof. James J. Binney
Rudolf Peierls Centre for Theoretical Physics, Oxford University, UK

Abstract

The study of the Milky is expected to have a major impact on our understanding of how galaxies form and evolve. "Near-field cosmology" is being vigorously pursued through a series of major surveys of the Galaxy's stellar content (2-MASS, SDSS, RAVE, Hermes, Apogee, Gaia) that are either in hand or pending. It will be argued that what we want to know is deeply buried in these data and can only be extracted by comparing the surveys with a hierarchy of dynamical models of ever increasing complexity. Work currently being done to build such hierarchical models will be described, and some early results from this work will be summarised.

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