Found 41 talks width keyword science

tRjiJVbop5I-thumbnail
Tuesday September 26, 2023
Notice (8): Undefined index: speakers [APP/View/Helper/FunctionsHelper.php, line 167]
Imperial College London

Abstract

Simons Observatory (SO) is a new Cosmic Microwave Background telescope currently under construction in the Atacama Desert, close to ALMA and other recent CMB telescopes. It will have six small aperture (42cm) telescopes (SATs), and one large aperture (6m) telescope (LAT), observing at 30-280GHz (1-10mm) using transition edge sensors (TES) and kinetic inductance detectors (KIDs). As well as observing the polarisation of the CMB to unprecedented sensitivity, the LAT will perform a constant survey at higher angular resolution, enabling the systematic detection of transient sources in the submm, with large overlap of optical surveys such as LSST, DESI and DES. As well as giving an overview of SO, I summarise the types of transient sources that are expected to be seen by SO, including flaring stars, quasars, asteroids, and man-made satellites.


vxBDH89Fk94-thumbnail
Thursday September 21, 2023
Notice (8): Undefined index: speakers [APP/View/Helper/FunctionsHelper.php, line 167]
ESO
IAC

Abstract

Astronomy has traditionally been an open science with a wide-spread attitude of sharing and exchange of best practices. Outside of astronomy, a strong movement towards Open Access Publishing has taken place during recent years, which is now affecting all scientific subject areas.

In this presentation, we will give a quick overview of what Open Access is and what it means for astronomy, and will review the current publishing models of core astronomy journals. A special focus will be the support libraries provide to scientists to make the best use of the Open Access options available to them, as well as the ways in which librarians help to shape movements in scholarly communication in order to establish a more collaborative, transparent publishing landscape.

 


Or79N9L25so-thumbnail
Thursday June 8, 2023
Notice (8): Undefined index: speakers [APP/View/Helper/FunctionsHelper.php, line 167]
Leibniz Institute for Astrophysics Potsdam, AIP, Germany

Abstract

 

In this seminar I will focus on how the avalanche of new data changes our views on how our Galaxy formed and evolved. Precise astrometric, spectroscopic, photometric and asteroseismic data can be combined to pin down different processes that have shaped the Milky Way. This data will be discussed and illustrated with examples of what is possible to achieve by combining chemistry , kinematics and age information. In particular, the impact of asteroseismology of red giants on Galactic Archaeology in the context of large spectroscopic surveys will be highlighted. Finally, it will be shown why more data is needed and what are some of the future plans for the next 10-20 years.

nBbFGfhVS10-thumbnail
Friday May 26, 2023
Notice (8): Undefined index: speakers [APP/View/Helper/FunctionsHelper.php, line 167]
Universidad Nacional Autonoma de Mexico

Abstract

We present the extended data release of the Calar Alto Legacy Integral Field Area (CALIFA) survey (eDR). It comprises science-grade quality data for 895 galaxies obtained with the PMAS/PPak instrument at the 3.5 m telescope at the Calar Alto Observatory along the last 12 years, using the V500 setup (3700-7500Å, 6Å/FWHM) and the CALIFA observing strategy. It includes galaxies of any morphological type, star-formation stage, a wide range of stellar masses ( ∼10^7-10^12 Msun), at an average redshift of  ∼0.015 (90\% within 0.005 < z <0.05). Primarily selected based on the projected size and apparent magnitude, we demonstrate that it can be volume corrected resulting in a statistically limited but representative sample of the population of galaxies in the nearby Universe. All the data were homogeneously re-reduced, introducing a set of modifications to the previous reduction. The most relevant is the development and implementation of a new cube-reconstruction algorithm that provides an (almost) seeing-limited spatial resolution (FWHM PSF  ∼1.0").  Furthermore we present the analysis performed using the pyPipe3D pipeline for these dataset. We include a description of (i) the analysis performed by the pipeline, (ii) the adopted datamodel for the derived spatially resolved properties and (iii) the catalog of integrated, characteristics and slope of the radial gradients for a set of observational and physical parameters derived for each galaxy. All these data has been distributed through the following webpage: http://ifs.astroscu.unam.mx/CALIFA_WEB/public_html/


-lly6HXpvh8-thumbnail
Thursday May 25, 2023
Notice (8): Undefined index: speakers [APP/View/Helper/FunctionsHelper.php, line 167]
ObAS and UJKZ

Abstract

One of the most active areas of research of the last decade is undoubtedly the study of the effects of baryons on the observed dynamics of galaxies. This particularly led to the establishment of some fundamental scaling relations, which characterise the dependence of the abundance of baryons on the properties of galaxies' dark matter haloes. Among these fundamental relations, the stellar–to-halo mass relation appears to be one of the most investigated.
In this talk, I will present the less commonly explored neutral hydrogen-to-halo mass relation constructed using high-quality extended HI rotation curves of isolated rotationally-supported disk galaxies, selected from the SPARC and LITTLE THINGS databases. I will discuss how we constrain the dark matter halo of these galaxies using a Navarro-Frenk-White cuspy density profile and a semi-analytic Dekel-Zhao density profile and how we investigate the scaling relations between baryons and halo parameters.


6Iproe6Zwb4-thumbnail
Thursday May 4, 2023
Notice (8): Undefined index: speakers [APP/View/Helper/FunctionsHelper.php, line 167]
IAC

Abstract


Understanding stellar structure and evolution significantly impacts our understanding of the tight-knit evolution of galaxies and exoplanet systems. However, hidden behind the luminous layers of the stellar atmosphere, the deep interior of a star is eluding from direct measurements. The seismic study of waves propagating the deep interior provides the only way to measure the internal structure, dynamics, and mixing in any given star and compare it to theoretical models.

With the photometric data from space missions, such as the NASA Kepler telescope, a golden age has begun for seismology. In particular, the seismic studies of thousands of solar-like have led to numerous breakthroughs in our understanding of the stellar structure of red-giant stars. Complimentary information on stellar binarity, tidal forces, rotation, and lithium abundance provide additional constraints to characterize the advanced evolution of stars further and provide high-resolution insights into complex internal adjustments. Approaching a sample of ~1000 identified solar-like oscillators in binary systems, provided by the ESA Gaia and NASA TESS missions draws an exciting picture on the interaction of stellar and orbital evolution.

 

https://rediris.zoom.us/j/89275150368?pwd=QnNxc09KbmJMTmdaRmVGdjZYSlBqdz09
ID de reunión: 892 7515 0368

Código de acceso: 101169

https://youtube.com/live/6Iproe6Zwb4?feature=share


Oe00LDuJNfs-thumbnail
Tuesday April 18, 2023
Notice (8): Undefined index: speakers [APP/View/Helper/FunctionsHelper.php, line 167]
University of Oxford

Abstract

 

Nowadays, it is widely accepted that most galaxies undergo an active phase in their evolution. The impact of the energy released by active galactic nuclei (AGN) in the interstellar medium (ISM) of the host galaxy has been proposed as a key mechanism responsible for regulating star formation (SF). The mid-infrared (IR) is the ideal spectral range to investigate the nuclear/circumnuclear regions of AGN since dust extinction is significantly lower compared to the visible range. Furthermore, it provides unique tracers to study the AGN-SF connection such as H2 rotational lines, fine structure lines and Polycyclic Aromatic Hydrocarbons (PAHs). PAHs are also a powerful tool to characterize the ISM in different environments.

Recently, we presented new JWST/MIRI MRS spectroscopy of three Seyfert AGN in which we compare their nuclear PAH emission with that of star-forming regions. This study represents the first of its kind to use sub-arcsecond angular resolution data of local luminous Seyferts (Lbol > 10^44.5 erg/s) with a wide wavelength coverage (4.9-28.1 μm). Our results showed that a suite of PAH features is present in the innermost parts of these Seyfert galaxies. We found that the nuclear regions of AGN lie at different positions of the PAH diagnostic diagrams, whereas the SF regions are concentrated around the average values of SF galaxies. Furthermore, we find that the nuclear PAH emission mainly originates in neutral PAHs while, in contrast, PAH emission originating in the star forming regions favours small ionised PAH grains. Therefore, our results provide evidence that the AGN have a significant impact on the ionization state and size of the PAH grains on scales of ~142-245 pc. This is fundamental since PAH bands are routinely used to measure star-formation activity in near and far SF and active galaxies.

Finally, I will summarise our ongoing JWST work within the GATOS (Galactic Activity, Torus and Outflow Survey) collaboration. In particular, I will focus on our recent study about the survival of PAH molecules in AGN-driven outflows.


s5MlCz-9MFk-thumbnail
Thursday April 13, 2023
Notice (8): Undefined index: speakers [APP/View/Helper/FunctionsHelper.php, line 167]
Oxford University

Abstract


1q-4CLaYMUA-thumbnail
Tuesday March 28, 2023
Notice (8): Undefined index: speakers [APP/View/Helper/FunctionsHelper.php, line 167]
University of St. Andrew

Abstract

Galaxies and the dark matter halos in which they reside are intrinsically connected. That relationship holds information about key processes in galaxy and structure formation. In this talk, I will consider how the galaxy-halo connection depends on position within the cosmic web - the familiar decomposition of large-scale structure in filaments, knots and voids. Simulations demonstrate the various ways in which the cosmic web modulates the growth and dynamics of halos. The extent to which the cosmic web impacts on galaxies is more difficult to establish. For example, galaxies might be sensitive only to the evolution of the host halo, in which case any effect of the cosmic web on galaxies is secondary, and can be inferred from the halo's history. There is evidence, however - from simulations and observations - that the cosmic web also impacts on the evolution of galaxies via the effect it has on the broader gas ecosystem in which they are embedded, as well as through "pre-processing" effects on group scale. So, how should we think of the cosmic web in its role as a transformative agent of galaxies? And what physical processes can we convincingly constrain from observations and simulations? In this talk I highlight recent work that addresses these questions.


4cBJTBClvqc-thumbnail
Thursday March 23, 2023
Notice (8): Undefined index: speakers [APP/View/Helper/FunctionsHelper.php, line 167]
CEICO, Institute of Physics of the Czech Academy of Sciences

Abstract

I present the recent results obtained using the updated version of MG-MAMPOSSt, a code that constrains modified gravity (MG) models viable at cosmological scales using determination of galaxy cluster mass profiles with kinematics and lensing analyses. I will discuss limitations and future developments of this method in view of upcoming imaging and spectroscopic surveys, as well as the possibilities of including X-ray data to break degeneracy among model parameters. Finally I will show preliminary results about the constraints that can be obtained on the inner slope of dark matter profiles when adding the velocity dispersion of the Brightest Central Galaxy (BCG) in the dataset of MG-MAMPOSSt.


« Newer 1 | 2 | 3 | 4 | 5 Last >>