Site Map
Follow us on Facebook Follow us on Twitter YouTube channel
Centro de Astrofísica da Universidade do Porto
Out of this world: the first 2 Gyrs of cosmic time with the widest Lyman-alpha surveys

David Sobral

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 at z=2.23 to calibrate Lyman-alpha (CALYMHA). We are currently conducting and exploring unique ~10 deg^2 NB surveys with CFHT, Subaru and the INT to look for Lyman-alpha emitters at z=2.23-8.8. Surprisingly, we find a much higher space density of luminous Lyman-alpha emitters at z~6-7 than previously assumed, which we confirm spectroscopically with Keck and the VLT and that may be powered by PopIII stars. Our unique samples include sources even more luminous in Lyman-alpha than Himiko at z=6.6 (e.g. our CR7 galaxy), showing that ultra-luminous Lyman-alpha emitters are much more common than thought at z~6.6, with consequences for our understanding of re-ionisation and highly relevant for what J-PAS and EUCLID may be able to recover by conducting ultra-wide surveys.

4 February 2015, 13:30

Centro de Astrofísica
Rua das Estrelas
4150-762 Porto

Institute of Astrophysics and Space Sciences

Institute of Astrophysics and Space Sciences (IA) is a new but long anticipated research infrastructure with a national dimension. It embodies a bold but feasible vision for the development of Astronomy, Astrophysics and Space Sciences in Portugal, taking full advantage and fully realizing the potential created by the national membership of the European Space Agency (ESA) and the European Southern Observatory (ESO). IA resulted from the merging the two most prominent research units in the field in Portugal: the Centre for Astrophysics of the University of Porto (CAUP) and the Center for Astronomy and Astrophysics of the University of Lisbon (CAAUL). It currently hosts more than two-thirds of all active researchers working in Space Sciences in Portugal, and is responsible for an even greater fraction of the national productivity in international ISI journals in the area of Space Sciences. This is the scientific area with the highest relative impact factor (1.65 times above the international average) and the field with the highest average number of citations per article for Portugal.

Proceed on CAUP's website|Go to IA website