DOI | Resolve DOI: https://doi.org/10.1088/2041-8205/742/1/L8 |
---|
Author | Search for: Willott, Chris J.1 |
---|
Affiliation | - National Research Council of Canada. NRC Herzberg Institute of Astrophysics
|
---|
Format | Text, Article |
---|
ISSN | 2041-8205 |
---|
Subject | cosmology: observations; galaxies: active; galaxies: high-redshift; X-rays: galaxies |
---|
Abstract | It has been claimed that there is a large population of obscured, accreting black holes at high redshift and that the integrated black hole density at z = 6 as inferred from X-ray observations is ~ 100 times greater than that inferred from optical quasars. I have performed a stacking analysis of very deep Chandra X-ray data at the positions of photometrically selected z = 6 galaxy candidates. It is found that there is no evidence for a stacked X-ray signal in either the soft (0.5-2 keV) or hard (2-8 keV) X-ray bands. Previous work which reported a significant signal is affected by an incorrect method of background subtraction which underestimates the true background within the target aperture. The puzzle remains as to why the z = 6 black hole mass function has such a flat slope and a low normalization compared to the stellar mass function. |
---|
Publication date | 2011-10-31 |
---|
In | |
---|
Language | English |
---|
Peer reviewed | Yes |
---|
NPARC number | 19688676 |
---|
Export citation | Export as RIS |
---|
Report a correction | Report a correction (opens in a new tab) |
---|
Record identifier | 60a3d889-0722-4b97-a9f9-e257fa166c4e |
---|
Record created | 2012-03-19 |
---|
Record modified | 2020-04-21 |
---|