• Media type: E-Article
  • Title: Distance, Energy, and Variability of Quasar Outflows: Two HST/COS Epochs of LBQS 1206+1052∗
  • Contributor: Miller, Timothy R.; Arav, Nahum; Xu, Xinfeng; Kriss, Gerard A.; Plesha, Rachel J.; Benn, Chris; Liu, Guilin
  • Published: American Astronomical Society, 2018
  • Published in: The Astrophysical Journal, 865 (2018) 2, Seite 90
  • Language: Not determined
  • DOI: 10.3847/1538-4357/aad817
  • ISSN: 0004-637X; 1538-4357
  • Keywords: Space and Planetary Science ; Astronomy and Astrophysics
  • Origination:
  • Footnote:
  • Description: <jats:title>Abstract</jats:title> <jats:p>We analyze new <jats:italic>HST</jats:italic>/COS spectra for two quasar absorption outflows seen in the quasi-stellar object LBQS 1206+1052. These data cover, for the first time, absorption troughs from S <jats:sc>iv</jats:sc>, Si <jats:sc>ii</jats:sc>, and P <jats:sc>v</jats:sc>. From the ratio of the S <jats:sc>iv</jats:sc>* to S <jats:sc>iv</jats:sc> column densities, we measure the electron number density of the higher-velocity (−1400 km s<jats:sup>−1</jats:sup>, v1400) outflow to be <jats:inline-formula> <jats:tex-math> <?CDATA $\mathrm{log}({n}_{e})={4.23}_{-0.09}^{+0.09}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjaad817ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> cm<jats:sup>−3</jats:sup> and constrain the lower-velocity (−730 km s<jats:sup>−1</jats:sup>, v700) outflow to log(<jats:italic>n</jats:italic> <jats:sub> <jats:italic>e</jats:italic> </jats:sub>) &gt; 5.3 cm<jats:sup>−3</jats:sup>. The <jats:italic>n</jats:italic> <jats:sub> <jats:italic>e</jats:italic> </jats:sub> associated with the higher-velocity outflow is an order of magnitude larger than reported in prior work. We find that the previous measurement was unreliable since it was based on density-sensitive absorption troughs that were likely saturated. Using photoionization models, we determine the best <jats:italic>χ</jats:italic> <jats:sup>2</jats:sup>-minimization fit for the ionization parameter and hydrogen column density of the higher-velocity outflow: log(<jats:inline-formula> <jats:tex-math> <?CDATA ${U}_{{\rm{H}}})=-{1.73}_{-0.12}^{+0.21}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjaad817ieqn2.gif" xlink:type="simple" /> </jats:inline-formula> and log(<jats:inline-formula> <jats:tex-math> <?CDATA ${N}_{{\rm{H}}})={21.03}_{-0.15}^{+0.25}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjaad817ieqn3.gif" xlink:type="simple" /> </jats:inline-formula> cm<jats:sup>−2</jats:sup>, respectively. We calculate from <jats:italic>U</jats:italic> <jats:sub>H</jats:sub> and <jats:italic>n</jats:italic> <jats:sub> <jats:italic>e</jats:italic> </jats:sub> a distance of <jats:inline-formula> <jats:tex-math> <?CDATA ${500}_{-110}^{+100}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjaad817ieqn4.gif" xlink:type="simple" /> </jats:inline-formula> pc from the central source to the outflow. Using an SED attenuated by the v700 outflow yields a two-phase photoionization solution for the v1400 outflow, separated by a <jats:inline-formula> <jats:tex-math> <?CDATA ${\rm{\Delta }}U\approxeq 0.7$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjaad817ieqn5.gif" xlink:type="simple" /> </jats:inline-formula>. Otherwise, the resultant distance, mass flux, and kinetic luminosity are similar to the unattenuated case. However, the attenuated analysis has significant uncertainties due to a lack of constraints on the v700 outflow in 2017.</jats:p>
  • Access State: Open Access