Speaker
Description
The millimeter part of the spectrum is one of the least explored parts of a galaxy's spectral energy distribution (SED), yet it contains emissions from three fundamentally important physical processes: the thermal emission from dust, the free-free emission from ionized gas, and the synchrotron emission from relativistic charged particles moving in the galactic magnetic field.
During my presentation, I will give an in-depth description of the millimeter emission of the face-on spiral galaxy NGC 4254, which is part of the IMEGIN Large Program (Interpreting the millimeter Emission of Galaxies with IRAM-NIKA2; PI S. Madden) targeting 22 nearby galaxies in the millimeter continuum regime with the NIKA2 camera, mostly focusing on the interstellar dust component.
Specifically, I will show as the new millimeter data, combined with a suite of observations at other wavelengths (including metallicity measurements and CO and HI line intensity maps), were crucial to: put constraints on the FIR-mm SED of the galaxy and, consequently, on the dust mass content and the dust FIR slope; disentangle from dust contribution, free-free and synchrotron emission in the millimeter regime; constrain the dust-to-gas mass ratio, which provides a direct link to the galaxy chemical evolution and the reservoirs for dust production; study the microscopic properties of dust and their variation with the ambient conditions (in terms of density, temperature and metallicity of the inter-stellar medium); investigate the relation between dust and star formation in spiral arms, inter-arms regions, nuclear region, and on a global scale. These results were achieved by modeling the galaxy IR-to-radio SED, both on global and spatially resolved scales, using the hierarchical Bayesian fitting code HerBIE (Galliano et al. 2018), which includes the prescriptions from the dust evolution model THEMIS (Jones et al. 2017).
| Would you be interested in presenting a poster if the conference is oversubcribed? | Yes |
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