Is the Bremer Deep Field Ionised at z=7?

The talk will show that the population of star forming galaxies in the Bremer Deep Field (BDF) has formed two large ionised bubbles. The sources  in the BDF have been completed with a set of expected, though not detected, low luminosity sources at z ~ 7.  We have estimated the number of ionising photons produced per second by the different star forming galaxies in the BDF and have compared it with the number that would be required to reionise the two bubbles, using as reference the ionising emissivities derived from the AMIGA cosmological evolutionary model. In this model we distinguished between single and double reionisation scenarios. We find that with a Lyman continuum escape fraction of 10%, the two regions we have defined in the BDF would be reionised in the single reionisation scenario, with slightly larger values (up to around 15%) required for the double ionisation case. The rather small values of the escape fraction required to reionise the BDF regions are compatible with the low fraction of Lyα emitters discovered in the BDF. Finally, we have noticed that the non–detected low luminosity sources represent the main contribution to the BDF ionising flux.

11/05/2021 - 12:30
Jose Miguel Rodriguez Espinosa
IAC, España