Astronomical Observatory Tuesday Seminar, 31 Mar 2025, Subhrata Dey (NCBJ,PL) скачать в хорошем качестве

Astronomical Observatory Tuesday Seminar, 31 Mar 2025, Subhrata Dey (NCBJ,PL)

Subhrata Dey National Center of Nuclear Research, PL Title: Bridging the Gap: From UV/IR to Radio via SED Modeling of Infrared Bright Galaxies Abstract: Luminous and Ultra-luminous Infrared Galaxies (U/LIRGs) are extreme star-forming galaxies, typically triggered by interactions or mergers of gas-rich galaxies. Their infrared emission is dominated by warm dust heated by active galactic nuclei (AGN) and starbursts, positioning them as a transitional phase between gas-rich galaxies and red, dead ellipticals. U/LIRGs offer a unique laboratory for studying the evolution from star-forming galaxies to elliptical galaxies. In this seminar, I will discuss the global astrophysical properties of a sample of 25 infrared-bright galaxies, combining the spectral energy distribution SED) modeling results of 11 nearby LIRGs (redshift lower than 0.04) and 14 ULIRGs (redshift lower than 0.5) across ultraviolet (UV), infrared (IR), and radio wavelengths. The focus will be on bridging UV-IR and radio-only SED modeling, which have traditionally been studied independently. By integrating these regimes, I aim to gain deeper insights into the physical processes driving galaxy evolution. Additionally, I will introduce a physically motivated approach to radio-only SED modeling that accounts for low-frequency absorption and the complex nature of radio continuum emission originating from multiple star-forming regions with varying compositions or geometric orientations. I will also present efforts to calibrate radio continuum emission for deriving the radio star formation rate (SFR), an extinction-free diagnostic of star formation activity.