On the black hole accretion rates of high redshift Lyman-alpha emitters
Exploring the High-Redshift Universe with Current and Future Facilities
Date Submitted
2017-04-14 13:37:24
Joao Calhau
David Sobral (Lancaster University), Andra Stroe (ESO), Jorryt Matthee (Leiden University), Sergio Santos (Lancaster University)
Lancaster University
I will present new results regarding the typical black hole accretion rates of Lya emitters across cosmic time and how they compare with their star formation rates. We explore Chandra X-ray data and a large sample of ~4K Lya emitters emitters in 14 redshift slices from z~2 to z~6 in the COSMOS field. We find that from z~2-4, a significant fraction of the brightest Lya emitters are highly accreting (~0.2 M_sun/yr) X-ray sources, but above z~4 even the brightest Lya emitters are not X-ray sources. Interestingly, once direct detections are removed, our X-ray stacking reveals the extremely low X-ray activity of Lya emitters in general. Overall, our results reveal that Lya emitters can be split into two main populations regarding the activity of their central super massive black holes: the majority shows little to no growth, with also very low SFRs, while a fraction of the sources, at the brightest Lya luminosities, are rapidly growing their black holes.
Schedule
id
date time
16:30 - 18:00
17:30
Abstract
On the black hole accretion rates of high redshift Lyman-alpha emitters