Members

Researchers

Michaela Kraus

Michaela is a senior researcher and a head of the Working group Physics of Hot Stars. Her research is dedicated to evolved massive stars with focus on B[e] supergiants, Yellow Hypergiants, Luminous Blue Variables, and classical blue supergiants. She is investigating their pulsation and mass-loss behavior, as well as the dynamics and chemistry of their circumstellar matter and the interaction of the ejected material with the local interstellar medium. For her research she developed several numerical codes that are continuously improved and used to analyze and interpret observational data from the optical up to the radio regime.

Contacts:

Pavel Koubský

Pavel is a emeritus researcher. His main research interests are early-type stars and their rapid variability, close binaries, and Be stars. In past he served as a head of the Stellar Physics department and a head of the Working Group Physics of Hot Stars, He also was the member of the Institute Council of the ASU. He was responsible for two upgrades of the Perek 2m telescope in the period 1982-1987 and 1996-1198.

Contacts:

  • email: pavel.koubsky @ asu.cas.cz

Jiří Kubát

Jiří is a senior researcher. His main research interests are radiative transfer and radiation-matter interactions (NLTE physics), modelling of stellar atmospheres and stellar winds. He is an author of a computer code for calculations of NLTE model stellar atmospheres and their emergent radiation. In past he served as a head of the Stellar Physics department, as a deputy director of the Astronomical Institute, and as a member of the Institute Council. Currently he represents the Czech Republic as a member of the Board of Directors of the international scientific journal Astronomy and Astrophysics.

Contacts:

Brankica Kubátová

Brankica is a senior researcher and a head of the Stellar Physics Department. Her main expertise lies in the area of hot, massive stars and their winds. , She is most known for work on the radiative transfer in inhomogennous (i.e., clumped) stellar winds. Her research aims to test how physical processes in the stellar winds influence mass-loss rates determination. She is also interested in quantitative spectroscopy, i.e., analysing spectroscopic data by means of detailed quantitative modelling in order to determined accurate values of the stellar and winds parameters.

Contacts:

Péter Németh

Peter is a researcher. He investigates hot subdwarf stars and binaries. He applies TLUSTY atmosphere models to reproduce ultraviolet and optical spectral observations. His field of research also includes the spectroscopy of chemically peculiar stars, evolved, compact objects, as well as spectral disentangling and the modeling of radiative interactions in close binary systems.

Contacts:

Olga Maryeva

Olga is a researcher. Before coming to the Czech Republic, she worked at Russian 6-m telescope (Special Astrophysical observatory), where she defended my PhD in 2016. Her main field is an investigation of evolved massive stars on the stages when the hydrogen is already exhausted in their cores, and the stars are rapidly evolving towards supernova explosion. Her goal is to understand the physics of processes leading to the transition between various evolutionary stages, and the evolutionary links between such groups of objects as Blue Supergiants, Luminous Blue Variables, Red Supergiants and Wolf-Rayet stars.

Contacts:

  • email: olga.maryeva @ asu.cas.cz
  • phone: +420 323 620 217
  • ORCID

Joris Vos

Joris is a researcher. He got his master in astronomy at the University of Leuven, and spent a year at the University of Copenhagen (DK) for his master thesis. He got his PhD at the University of Leuven (BE), was a FONDECYT fellow at the University of Valparaiso (CL) and a Humboldt fellow at the University of Potsdam (DE). His study is focused on binary evolution and hot subdwarf stars. He uses the binary hot subdwarf population to study the interaction  mechanisms in binary stars containing a red giant. This involves both spectroscopic and photometric observations of hot subdwarfs and their progenitors, and theoretical modeling work of binary interactions. He also works on using AI algorithms to increase the accuracy of binary population synthesis codes, by combining binary evolution tracks from MESA with galactic population properties.

  • email: joris.vos @ asu.cas.cz
  • phone: +420 323 620 140
  • ORCID

Michalis Kourniotis

Michalis is a researcher at Astronomical Institute of Czech Academy of Sciences. Observational study of advanced stages of massive stars; Luminous Blue Variables, Yellow Hypergiants, B[e] supergiants – Massive binaries – Winds from massive stellar clusters; simulations, population synthesis.

Contacts:

  • email: kourniotis @ asu.cas.cz
  • phone: +420 323 620 136
  • ORCID

Postdocs

Julieta Sanchez Arias

Julieta is a postdoc. After obtaining her PhD at La Plata National University in Argentina, Julieta developed her research activities as a postdoc at the Astrophysics Institute of La Plata for one year. Currently, she is a postdoc at the ASU. Her main interest is the study of stellar oscillations through the development of stellar models and the analysis of light curves. At present, she is focused on pulsations of massive stars and its connection with the stellar winds, but she is also interested in pulsating A-F stars, low mass WDs and hot-Jup planets.

Contacts:

  • email: julieta.sanchez @ asu.cas.cz
  • phone: +420 323 620 217
  • ORCID

Jakub Fišák

Jakub is a postdoc. His research focuses on massive, hot stars and their winds. In particular, he is interested in NLTE radiative transfer and the modelling of stellar atmospheres and stellar winds. He is working on the development of an NLTE 3-D Monte Carlo radiative transfer code that will be able to handle wind inhomogeneities and other 3-D phenomena in the winds of massive, hot stars.

Contacts:

  • email: fisak @ monoceros.physics.muni.cz
  • phone: +420 323 620 328
  • ORCID

Alex Camilo Gormaz Matamala

Alex got his PhD in Valparaíso, Chile, calculating self-consistent solutions between the hydrodynamics and the line-acceleration for the stellar wind of massive stars. These self-consistent solutions are important because the evolution of massive stars is heavily determined by the strength of their winds. Currently, Alex is dedicated to the application of the new wind prescription for the evolution of massive stars, thus finding new predictions concerning chemical abundances, spectroscopic phases and final masses prior to the core collapse. Such predictions are contrasted with observational diagnostics.

Contacts:

  • email: alex.gormaz @ asu.cas.cz
  • phone: +420 323 620 140
  • ORCID

PhD students

Suryani Guha

Suryani is a PhD student of Charles University/ASU, Stellar Physics Department. She has accomplished her M.Sc degree from India. Her area of interests are physics, stellar astronomy, astroseismology. Her PhD project is based on ‘Study of pulsations in evolved massive stars’. At present she is working with TESS targets, blue supergiants and MESA code. She is also interested in spectroscopic data analysis, Photometry and observational astronomy.

Contacts:

  • email: suryani.guha @ asu.cas.cz
  • phone: +420 323 620 141

Kateřina Pivoňková

Kateřina is a PhD student at Masaryk University in Brno and at the Astronomical Institute of the Czech Academy of Sciences. In her current research, she focuses on structured winds of hot stars, specifically on studying the development of inhomogeneities in stellar winds and the instabilities responsible for the formation of individual structures within the wind. She employs three-dimensional radiative hydrodynamic models for this purpose. Additionally, she investigates spectroscopically variable stars and the observational consequences of the existence of structures in stellar winds.

Contacts:

  • email: 500148 @ mail.muni.cz
  • phone: +420 323 620 140

Former members

Tiina Liimets (ORCID), Mauricio Cabezas