Abstract

Exploring the high-redshift Universe
Out of this world: exploring the Universe with the largest emission-line surveys
David Sobral
Lancaster University
I will present new results regarding the first 2 Gyrs of cosmic time using very wide-field Lyman-alpha narrow-band surveys, including a large, matched Lya-Ha survey to calibrate Lyman-alpha (CALYMHA). Surprisingly, we find a much higher space density of very luminous Lyman-alpha emitters at z=5-7 than previously assumed, which we confirm spectroscopically with Keck and the VLT and that show signatures of PopIII-like stellar populations and/or direct collapse black holes. I will present new follow-up observations and modelling of the impressive CR7 galaxy which we discovered, but also of other CR7-like sources, which show that CR7 is definitely not alone, but part of an extremely interesting population which we can study in detail ahead of JWST. Our results are extremely important for our understanding of re-ionisation and galaxy evolution and highly relevant for what e.g. J-PAS and EUCLID may be able to recover by conducting ultra-wide surveys at high-z.

Schedule

Monday
13:30 - 15:00
13:45
EX - LT2 (200)

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