Please use this identifier to cite or link to this item: http://hdl.handle.net/2381/38632
Title: X-ray selected BALQSOs
Authors: Page, M. J.
Carrera, F. J
Ceballos, M.
Corral, A.
Ebrero, J.
Esquej, P.
Krumpe, M.
Mateos, S.
Rosen, S.
Schwope, A.
Streblyanska, A.
Symeonidis, M.
Tedds, J. A.
Watson, M. G.
First Published: 8-Oct-2016
Publisher: Oxford University Press (OUP), Royal Astronomical Society
Citation: Monthly Notices of the Royal Astronomical Society, 2016
Abstract: We study a sample of six X-ray selected broad absorption line (BAL) quasi-stellar objects (QSOs) from the XMM-Newton Wide Angle Survey. All six objects are classified as BALQSOs using the classic balnicity index, and together they form the largest sample of X-ray selected BALQSOs. We find evidence for absorption in the X-ray spectra of all six objects. An ionized absorption model applied to an X-ray spectral shape that would be typical for non-BAL QSOs (a power law with energy index α = 0.98) provides acceptable fits to the X-ray spectra of all six objects. The optical to X-ray spectral indices, αOX, of the X-ray selected BALQSOs, have a mean value of 〈αOX〉 = 1.69 ± 0.05, which is similar to that found for X-ray selected and optically selected non-BAL QSOs of similar ultraviolet luminosity. In contrast, optically-selected BALQSOs typically have much larger αOX and so are characterised as being X-ray weak. The results imply that X-ray selection yields intrinsically X-ray bright BALQSOs, but their X-ray spectra are absorbed by a similar degree to that seen in optically-selected BALQSO samples; X-ray absorption appears to be ubiquitous in BALQSOs, but X-ray weakness is not. We argue that BALQSOs sit at one end of a spectrum of X-ray absorption properties in QSOs related to the degree of ultraviolet absorption in C IV 1550Å.
DOI Link: 10.1093/mnras/stw2560
ISSN: 0035-8711
eISSN: 1365-2966
Links: http://mnras.oxfordjournals.org/content/early/2016/10/08/mnras.stw2560
http://hdl.handle.net/2381/38632
Version: Publisher Version
Status: Peer-reviewed
Type: Journal Article
Rights: Creative Commons “Attribution Non-Commercial No Derivatives” licence CC BY-NC-ND, further details of which can be found via the following link: http://creativecommons.org/licenses/by-nc-nd/4.0/ Archived with reference to SHERPA/RoMEO and publisher website.
Appears in Collections:Published Articles, Dept. of Physics and Astronomy

Files in This Item:
File Description SizeFormat 
MNRAS-2016-Page-mnras-stw2560.pdfPublished (publisher PDF)259.72 kBAdobe PDFView/Open


Items in LRA are protected by copyright, with all rights reserved, unless otherwise indicated.