Found 24 talks width keyword CMB

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Wednesday December 5, 2012
Dr. Beatriz Ruiz Granados
Universidad de Granada

Abstract

Magnetic fields at galactic and larger scales is a challenging issue for astrophysics and cosmology. In this talk, I'll review the methods to detect magnetic fields at these scales as well as I'll revise the field structure of the Milky Way and its dynamical implications over the gas distribution. In the second part, I'll review the updated works about effects of primordial magnetic fields on large scale structure and I'll show you preliminary results on its imprint on cosmic microwave background. 


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Thursday February 9, 2012
Dr. José Alberto Rubiño
Instituto de Astrofísica de Canarias, Spain

Abstract

The European Space Agency's Planck satellite was launched on 14 May 2009, and has been surveying the sky stably and continuously since 13 August 2009. Its performance is well in line with expectations, and it will continue to gather scientific data until the end of its cryogenic lifetime. I will present the first scientific results of the mission, which appeared as a series of 26 papers at the beginning of this year 2011, covering a variety of astrophysical topics. In particular, I will focus on the results on galactic diffuse emissions, as well as the first results on galaxy clusters detected by means of the Sunyaev-Zeldovich effect.


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Thursday December 1, 2011
Dr. Carlos Hernandez-Monteagudo

Abstract

I revisit the claim of Dark Energy detection after stacking CMB data on the angular position of voids and superclusters in Sloan Data. I examine the theoretically expected amplitude for the ISW-induced signal and explore its scale dependence. I next confront these predictions with results obtained from real WMAP data, and evaluate the degree of agreement and the possible presence of contaminants. In a more general context, I address the possibility of unveiling the signature of Dark Energy on the CMB by looking at isolated regions on the sky hosting high-threshold projected under/over-densities: this constitutes a novel approach since it is less sensitive to large angle systematics commonly present in large scale structure surveys.


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Wednesday October 26, 2011
Dr. Mar Bastero
Universidad de Granada, Spain

Abstract

In this talk I will review the subject of cosmological inflation, a period of early accelerated expansion. I will discuss Friedmann-Robertson-Walker cosmology and the horizon and flatness problems, and introduce inflation as a solution to those problems. I will also discuss the generation of  the primordial (scalar and tensor) spectrum of perturbations which provides the seeds for the large scale structure in the Universe. I will review quickly the status of observations in relation to the inflationary parameters, and then the implications for model building.


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Thursday July 21, 2011
Dr. Martín Lopez Corredoira
Instituto de Astrofísica de Canarias, Spain

Abstract

I will review some theoretical ideas in Cosmology different to the standard "Big Bang": the Quasi-steady State model, Plasma Cosmology model, non-cosmological redshifts, alternatives to non-baryonic dark matter and/or dark energy, and others. Some open problems of Cosmology within the standard model will also be summarized.


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Wednesday July 20, 2011
Dr. Miguel Ángel Sánchez Conde
Instituto de Astrofísica de Canarias, Spain

Abstract

What's the dark matter made of? Do we have any idea of the kind of particle that should constitute ~85% of the matter content of the Universe? In this talk, I will briefly explain the properties that such a particle might have and will present some of the proposed candidates that arise from beyond the Standard Model of particle physics. Next stop will be to give an overview of the present status of dark matter searches, mainly focusing on gamma-rays. There is a tremendous effort currently ongoing that involves an impressive battery of experiments both at the lab and observatories around the world.
In a second part,  the importance of N-body cosmological simulations for the understanding of how dark matter halos form and evolve from the early Universe will be discussed. At this point, some problems arise that it's worth mentioning and that will hopefully lead to debate.

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Tuesday July 19, 2011
Dr. Ricardo Tanausu Génova Santos
Instituto de Astrofísica de Canarias, Spain

Abstract

In the first part of this talk I will present a historical review of the CMB observations, one of the most powerful cosmological probes. Following the first talk of this series, where Jose Alberto described the basic parameters that define the standard cosmological model, I will here summarize the constraints to these parameters that have been derived from these observations. I will also describe the current challenges in this field, in particular the detection of the inflation's B-mode signal through CMB polarization observations, as well as the experiments that have been developed worldwide to this aim, including IAC's QUIJOTE. In the second part, I will focus on the so-called ``missing baryon problem'', i.e. the fact that the half of the expected baryon content of the local universe remains yet undetected. I will describe the theoretical studies that provide hints on where these baryons could be located, and the observational efforts that have been undertaken in this regard.


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Monday July 18, 2011
Dr. José Alberto Rubiño
Instituto de Astrofísica de Canarias, Spain

Abstract

This is the first talk of a series of four aimed to discuss about Cosmology. Here, I will review the basic concepts of the standard cosmological model, which will be further discussed in the following talks, as well as the observational evidence in support of the Lambda-CDM model. As the subject is very broad, I will focus the discussion on topics related with inflation, dark matter and dark energy. Moreover, I will mainly discuss large scale structure probes.


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Monday March 15, 2010
Prof. Kip S. Thorne
University of Caltech, USA

Abstract

Over the next decade or so, the gravitational-wave window onto the Universe will be opened in four frequency bands that span 22 orders of magnitude: The high-frequency band, 10 to 10,000 Hz (ground-based interferometers such as LIGO and VIRGO), the low-frequency band, 10-5 to 0.1 Hz (the space-based interferometer LISA), the very-low frequency band, 10-9 to 10-7 Hz (pulsar timing arrays), and the extremely-low-frequency band, 10-18 to 10-16 Hz (polarization of the cosmic microwave background). This lecture will describe these four bands, the detectors that are being developed to explore them, and what we are likely to learn about black holes, neutron stars, white dwarfs and early-universe exotica from these detectors' observations.


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Tuesday February 23, 2010
Dr. Carlos Hernández-Monteagudo
Max-Planck Institute for Astrophysics, Germany

Abstract

The Atacama Cosmology Telescope (ACT) has been observing the southern sky in the millimeter range with an angular resolution at the arc-minute level. An analysis of 228 square degrees observed at 148 GHz along a stripe centered at declination -53 degrees reveals the presence of the Silk damping tail in the temperature angular power spectrum of the Cosmic Microwave Background (CMB). This decaying tail becomes truncated by a rising spectrum at scales corresponding to few arcmins (l ~ 3000) whose origin is compatible with a unclustered population of unresolved point sources and some residual anisotropy due to Compton scattering of CMB photons off free electrons (the Sunyaev-Zel'dovich effect). Comparisons with other observations and constraints on different components giving rise to this secondary spectrum are discussed.

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