Abstract

Title of Abstract
Emission Line Galaxy Demographics in the last 10 Gyrs with CANDELS Broadband Colours
Session
Dust, Gas and Star Formation in Galaxies Throughout Cosmic Time
Author
Joao Pedro Ferreira
Institution
University of Edinburgh
Co-Authors
James Dunlop, Vivienne Wild
Summary (maximum 250 words)
Concerted efforts in high-z galaxy evolution in recent years have formed a consistent picture of rising star formation, peaking at z=2 that exponentially decreases until today. Yet, the details of how this transition from a gas-rich, bursty universe to today's largely quiescent one needs an explanation, especially in the light of the evidence for a main sequence of star formation and different feedback properties of galaxies below and above the knee of the mass function.

A better understanding of galaxy formation needs large samples of objects down to the masses of dwarf galaxies:

Using a combination of the wealth of deep (H200A) emission-line galaxies (ELGs) in [OII], [OIII] and H-alpha and estimate equivalent widths (EWs) to produce ELG EW distributions over 0.310^9 for all these lines.

The results agree with theoretical models and complementary observations like narrowband or spectroscopic measurements.
The EW distributions display long tails of extreme equivalent widths for [OIII] and H-alpha and, more surprisingly, very high fractions (up to 30%) of ELGs in the described mass range.
While [OIII] and H-alpha fractions both increase from z=0.3 to z=2, [OII] does not follow this increase, which indicates that a transition in [OIII]/[OII] and ionization parameter is at work at z=2 for these objects.
Attachment

Schedule

Session Time
16:30 - 18:00
Talk start
16:45
Day
Wednesday

RASLogo