Colloquium Details

Palle Moller (European Southern Observatory (ESO))

"Connecting visible galaxies and invisible galaxies"

Abstract
Damped Lyman-alpha Absorbers (DLAs) have long been, and still are, our best windowinto understanding the formation of non-primordial elements (metals) at high redshifts.Unfortunately, it initially proved extremely difficult to detect the absorbers in emission,and therefore the vast absorption metallicity database covering redshifts from 0 to 6has effectively remained unconnected to the galaxies seen in emission.On the other hand, scaling relations for galaxies seen in emission are limited by theneed to have enough flux, i.e. they are highly biased towards increasingly massivegalaxies as we move to higher redshifts. The bulk of the galaxy population of theuniverse is not included.Being able to connect the two would radically impact our understanding of galaxy/gasco-evolution back to redshifts 6. Within recent years the study of DLAs in emissionhas come of age. We are now finally starting to create samples and to extractscaling relations. The long-term goal is to use those scaling relations to connectemission and absorption selected samples. Already the redshift evolution of themass-metallicity relation has been determined back to a redshift of 5.1, revealingthat the way galaxies grow is different before and after "cosmic high noon"at z=2.5.


Held at 02:00PM on Friday 9th March, 2018 in the AAO Meeting Room (Room 7, 1st Floor, Building 2)