Tracing the Universe: X-ray surveys and cosmology

Τετάρτη 11 Μαρτίου 2020, 13:00-14:00

 

ΣΧΟΛΗ ΘΕΤΙΚΩΝ ΕΠΙΣΤΗΜΩΝ ΕΚΠΑ

ΤΜΗΜΑ ΦΥΣΙΚΗΣ

ΤΟΜΕΑΣ ΑΣΤΡΟΦΥΣΙΚΗΣ ΑΣΤΡΟΝΟΜΙΑΣ ΚΑΙ ΜΗΧΑΝΙΚΗΣ

Σ Ε Μ Ι Ν Α Ρ Ι Ο

Τετάρτη 11 Μαρτίου 2020, 13:00-14:00
Αίθουσα Διαλέξεων Τομέα Αστροφυσικής, Αστρονομίας και Μηχανικής

Tracing the Universe: X-ray surveys and cosmology
Dr Elias Koulouridis
National Observatory of Athens

X-rays are produced in some of the most energetic processes in the Universe,
but because they are blocked by Earth's atmosphere, they can only be observed
from space. When X-ray telescopes observe the extragalactic Universe, they
basically see two sources: the hot gas pervading clusters of galaxies,
and Active Galactic Nuclei. As the most massive self-gravitating entities of
the universe, galaxy clusters are key objects for constraining cosmological
models: they are sensitive to the geometry of the space-time and to structure
growth. X-ray surveys have proven very effective in identifying large numbers
of galaxy clusters including many within the redshift range 1<zcorresponds to the formation epoch of massive clusters and thus, is of extreme
cosmological relevance. In this talk I will present some of the main results of
the XXL survey, ESA's XMM-Newton largest observational programme to date, but also
other current and future X-ray missions that are expected to yield large numbers of clusters.

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