Physics and chemistry of the Interstellar Medium

ASTROPHYSICAL MAGNETOHYDRODYNAMICS

Astrophysical magnetohydrodynamics (MHD) is the field of research dealing with the dynamics of ionised gas interacting with magnetic fields in various astrophysical objects. Magnetic fields play crucial role in evolution of planets, stars, galactic interstellar medium, accretion disks and astrophysical jets. The presence of magnetic fields in astrophysical environments induces magnetohydrodynamical instabilities leading to turbulence. A significant part of mater in the Universe appears in the ionised state. Electric currents flowing in ionised astrophysical media are sources of cosmic magnetic fields (Ampere’s law) and their mutual interactions lead to Lorentz forces influencing the dynamics of ionised gasses. Research activities carried out at Institute of Astronomy, NCU include generation of galactic magnetic fields, propagation of galactic cosmic rays and evaluation of their role in cosmological evolution of galaxies, propagation and stability of astrophysical jets, as well as early stages of planet formation.

ASTROPHYSICAL MASERS

The formation of high-mass stars is a complex process, being far less understood than it is for low-mass stars. Gas accretion, molecular outflows and shock waves are among the first phenomena indicating star-forming activity that can be studied by mean of radio molecular lines. In the environment of massive stars the radiation of molecules is sometimes amplified by the maser mechanisms and it can be easily detectable with a medium size radio telescope. Furthermore, the maser radiation is observed from deeply embedded protostars and distance galaxies without being distorted by the interstellar medium. Studies with the use of the 32m telescope concerns the search for high-mass stars in the very early stages of evolution.

MOLECULAR ASTROPHYSICS (ASTROCHEMISTRY)

Interstellar Medium (ISM) is a dominant reservoir of mass in galaxies. ISM gives us an opportunity to study formation and death of stars at small scales and physical and chemical evolution of galaxies at large scales. Our research concerns observations of gas and dust in a broad range of electromagnetic spectrum using the largest telescopes and their networks (ESO, ESA, SOFIA and VLBI). This way, we investigate how stars are formed and how they interact with the surrounding ISM, determine the chemical composition of both dense and diffuse medium and the initial conditions of planet formation.

STRUCTURE OF THE GALAXY AND INTERSTELLAR MATTER

Interstellar medium fills the space in our Galaxy; it is especially concentrated in disk. The presence of clouds of interstellar matter is manifested in various ways. Our studies are observations in the visible range, as well as near-infrared, searching for relationships between elements of absorption spectra of interstellar clouds. The most significant results so far is determining the average extinction rule on the basis of vast collection of photometric data and pointing to a possible relationship between the shape of extinction curves and the proportions of intensities of diffuse interstellar bands. We have also defined the relationship between the density of interstellar gases and distance, at present it is the most reliable manner of distance measuring the Galaxy disk.