Modelling X-ray RMS spectra II: the ultrafast outflow of PDS 456

Härer L, Parker ML, Joyce A, Igo Z, Alston WN, Furst F, Lobban AP, Matzeu GA, Reeves JN (2021)

Publication Type: Journal article

Publication year: 2021

Journal

Monthly Notices of the Royal Astronomical Society Oxford University Press

Book Volume: 500

Pages Range: 4506-4513

Journal Issue: 4

DOI: 10.1093/mnras/staa3559

Abstract

We present an improved model for excess variance spectra describing ultrafast outflows and successfully apply it to the luminous (L-bol similar to 10(47)erg s(-1)) low-redshift (z = 0.184) quasar Pico del Dias Survey (PDS) 456. The model is able to account well for the broadening of the spike-like features of these outflows in the excess variance spectrum of PDS 456, by considering two effects: a correlation between the outflow' velocity and the logarithmic X-ray flux and intrinsic Doppler broadening with v(int) = 10(4) km s(-1). Die models were generated by calculating the fractional excess variance of count spectra from a Monte Carlo simulation. We find evidence that the outflow in PDS 456 is structured, i.e. there exist two or more layers with outflow velocities 0.27-0.30 c, 0.41-0.49 c, and 0.15-0.20 c for a possible third layer, which agrees well with the literature. We discuss the prospects of generally applicable models for excess variance spectra for detecting ultrafast outflow's and investigating their structure. We provide an estimate for the strength of the correlation between the outflow' velocity and the logarithmic X-ray flux and investigate its validity.

Authors with CRIS profile

Lucia Härer Dr.Karl-Remeis-Sternwarte Bamberg, Astronomisches Institut

Involved external institutions

European Space Astronomy Centre (ESAC) ES Spain (ES) Catholic University of America US United States (USA) (US)

How to cite

APA:

Härer, L., Parker, M.L., Joyce, A., Igo, Z., Alston, W.N., Furst, F.,... Reeves, J.N. (2021). Modelling X-ray RMS spectra II: the ultrafast outflow of PDS 456. Monthly Notices of the Royal Astronomical Society, 500(4), 4506-4513. https://dx.doi.org/10.1093/mnras/staa3559

MLA:

Härer, Lucia, et al. "Modelling X-ray RMS spectra II: the ultrafast outflow of PDS 456." Monthly Notices of the Royal Astronomical Society 500.4 (2021): 4506-4513.

BibTeX: Download