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.
Solen Balman (Department of Astronomy and Space Sciences, Istanbul University)
Cataclysmic Variables (CVs) and related systems (e.g., AM CVn, Symbiotics) are compact systems with white dwarf (WD) primaries referred as accreting white dwarfs (AWDs). They are excellent laboratories to study astrophysical plasmas, accretion flows and disks, gas dynamics, outflows, and transient outbursts. Broadband noise and its variations in accretion flows have been a diagnostic tool for understanding the structure of accretion disks together with accretion history and state changes. CVs demonstrate band limited noise (mainly 1-6 mHz) in the optical, UV and X-ray energy bands, which can be adequately explained in the framework of the model of propagating fluctuations yielding break frequencies. I will discuss broadband noise structure in CVs with a broader sense including some different nonmagnetic AWDs elaborating on similarities along with spectral characteristics. The spectral and/or broadband noise studies show that advective hot flow structure (ADAF-like) resides inside nonmagnetic CV disks mainly detected in the X-ray regime (Balman 2020, Balman et al. 2022 and references therein) indicating other characteristics like outflows in the X-rays and warm absorber effects.
Journal Club takes place on Mondays at 11:00 AM in the Seminar Room. The seminar is given in English and is chaired by Angelos Karakonstantakis, Gergely Hajdu, and Fatemeh Kayanikhoo.
