by
Lise Christiansen(DARK Cosmology Centre, Copenhagen)
→
Europe/Stockholm
FC61
FC61
Description
Determining the chemical abundances is a key part in understanding the
evolution and nature of high redshift galaxies. We can only measure
metallicities with spectroscopic observations but since galaxies
become increasingly faint with redshift we have to rely on stacking of
many galaxy spectra or use scaling relations that are derived from
observations of low redshift galaxies. Strong gravitational lensing
that boosts the flux from background sources allow us to check that
the scaling relations are also valid in the high redshift universe.
A more uniform way to measure metallicities in high redshift galaxies
comes from galaxy absorption lines, either seen in quasar or gamma-ray
burst spectra that randomly probe intervening galaxies. However, it is
not well established how metallicities derived in emission correlate with
that in absorption. In this talk I will review recent analyses of the
metallicities in high redshift galaxies based on different
observational techniques, and recent efforts in combining information
from galaxies seen in emission and absorption.