Cake Talk: Georgios Magdis (Oxford) – University of Copenhagen

Dark Cosmology Centre > Calendar DARK > Calendar 2015 > Cake Talk: Georgios Ma...

Cake Talk: Georgios Magdis (Oxford)

Talk by: Georgios Magdis

Title: The evolving ISM of star forming galaxies over the last 10 Billion years


In the process of trying to understand galaxy evolution, over the last years we have managed to uncovered various scaling laws that are followed by the majority of star forming galaxies over the  last 10 billion years (or more). These scaling laws, among others, include a relation between the star formation rate (SFR) and the stellar mass of the galaxies (the main sequence of star-formation - MS), a relation between the SFR and the molecular gas of the galaxies and a relation between the total infrared  (LIR) and the 8micron monochromatic luminosity (L8).

In this talk I will present new insights  into a fourth scaling law, between  the LIR and the luminosity of the single ionised atom of carbon (LCII), as obtained  by a recent spectroscopic survey of intermediate redshift ULIRGs, with Herschel.

I will discuss how these scaling laws mirror the processes of star formation across cosmic time and how, when put together they:

- provide direct evidence that the decoupling of the physical properties of the galaxies from the total infrared luminosity is already at place by z~0.3, and

- point towards a secular evolution of galaxies and a minor role of mergers in the stellar built up of the galaxies.