The Colloquium takes place every Wednesday at 11:15 AM - Warsaw Copernicus Astronomical Centre online by means of Zoom platform. The Colloquium is given in English and chaired by dr Stanisław Bajtlik (bajtlik@camk.edu.pl). People from outside of the Copernicus Center are very welcome to participate. For technical detailes please contact Dr. Stanislaw Bajtlik.
Chandra Sekhar Saraf (Korea Astronomy and Space Science Institute)
The well established standard ΛCDM model of cosmology suffers from several challenges and disparities like the nature of dark matter and dark energy, accelerated expansion of the Universe and tensions in cosmological parameters derived from different observations. These shortcomings have raised questions on the validity of the ΛCDM model and led to increased interests towards alternative models of cosmology (dark energy models and Modified Gravity theories). Cross-correlation measurements at different redshift bins from the next-generation CMB experiments and galaxy surveys will provide us an unprecedented opportunity to put stronger constraints on alternative models of cosmology. However, in order to accurately quantify deviations from the ΛCDM model, it is crucial to mitigate the systematic errors that may bias the cross-correlation measurements. In this presentation, we will talk about various systematics that can impact the estimation of cosmological parameters in cross-correlation studies. We will present results from the first cross-correlation measurements between Planck CMB lensing potential and the Herschel Extragalactic Legacy Project (HELP) galaxy catalogues. In addition, we will also discuss the implications of leakage of objects in tomographic cross-correlation studies, through simulations performed with expectations from the upcoming LSST survey.
Journal Club takes place on Mondays at 11:15 AM in the Seminar Room. The presentation is given in English and is chaired by Journal Club Coordinators. Anyone interested in giving a Journal Club talk is encouraged to contact the email: journalclub(@camk.edu.pl).
Alex Markowitz (NCAC, Warsaw)
Based mostly on Munari, U., et al.: A&A, 701, A176 (2025), "T CrB: Overview of the accretion history, Roche-lobe filling, orbital solution, and radiative modeling".
