scholarly journals Constraining the geometry and kinematics of the quasar broad emission line region using gravitational microlensing

2019 ◽  
Vol 629 ◽  
pp. A43 ◽  
Author(s):  
D. Hutsemékers ◽  
L. Braibant ◽  
D. Sluse ◽  
R. Goosmann

The quadruply lensed quasar HE0435−1223 shows a clear microlensing effect that affects differently the blue and red wings of the Hα line profile in its image D. To interpret these observations, and constrain the broad emission line region (BLR) properties, the effect of gravitational microlensing on quasar broad emission line profiles and their underlying continuum has been simulated considering representative BLR models and microlensing magnification maps. The amplification and distortion of the Hα line profile, characterized by a set of four indices, can be reproduced by the simulations. Although the constraints on the BLR models set by the observed single-epoch microlensing signal are not very robust, we found that flattened geometries (Keplerian disk and equatorial wind) can more easily reproduce the observed line profile deformations than a biconical polar wind. With an additional independent constraint on the size of the continuum source, the Keplerian disk model of the Hα BLR is slightly favored.

2019 ◽  
Vol 487 (4) ◽  
pp. 5041-5061 ◽  
Author(s):  
Fred Hamann ◽  
Todd M Tripp ◽  
David Rupke ◽  
Sylvain Veilleux

Abstract Quasar outflows are fundamental components of quasar environments that might play an important role in feedback to galaxy evolution. We report on the emergence of a remarkable new outflow absorption-line system in the quasar PG1411+442 (redshift ∼0.089) detected in the UV and visible with the Hubble Space Telescope Cosmic Origins Spectrograph and the Gemini Multi-Object Spectrograph, respectively. This new ‘transient’ system contains thousands of lines, including Fe ii and Fe ii∗ from excited states up to 3.89 eV, H i∗ Balmer lines, Na i D λλ5890, 5896, and the first detection of He i∗ λ5876 in a quasar. The transient absorber is spatially inhomogeneous and compact, with sizes ≲0.003 pc, based on covering fractions on the quasar continuum source ranging from ∼0.45 in strong UV lines to ∼0.04 in Na i D. cloudy photoionization simulations show that large total column densities log NH(cm−2) ≳ 23.4 and an intense radiation field ≲0.4 pc from the quasar are needed to produce the observed lines in thick zones of both fully ionized and partially ionized gas. The densities are conservatively log nH(cm−3) ≳ 7 based on Fe ii∗, H i∗, and He i∗ but they might reach log nH(cm−3) ≳ 10 based on Na i D. The transient lines appear at roughly the same velocity shift, v ∼ −1900 km s−1, as a ‘mini-BAL’ outflow detected previously, but with narrower Doppler widths, b ∼ 100 km s−1, and larger column densities in more compact outflow structures. We propose that the transient lines identify a clumpy outflow from the broad emission-line region that, at its current speed and location, is still gravitationally bound to the central black hole.


Author(s):  
Matthew J Temple ◽  
Manda Banerji ◽  
Paul C Hewett ◽  
Amy L Rankine ◽  
Gordon T Richards

Abstract Using data from SDSS, UKIDSS and WISE, we investigate the properties of the high-frequency cutoff to the infrared emission in ≃5000 carefully selected luminous (Lbol ∼ 1047) type 1 quasars. The strength of ≃2 μm emission, corresponding to emission from the hottest ($T>1200\rm \, K$) dust in the sublimation zone surrounding the central continuum source, is observed to correlate with the blueshift of the C iv λ1550 emission line. We therefore find that objects with stronger signatures of nuclear outflows tend to have a larger covering fraction of sublimation-temperature dust. When controlling for the observed outflow strength, the hot dust covering fraction does not vary significantly across our sample as a function of luminosity, black hole mass or Eddington fraction. The correlation between the hot dust and the C iv line blueshifts, together with the lack of correlation between the hot dust and other parameters, therefore provides evidence of a link between the properties of the broad emission line region and the infrared-emitting dusty regions in quasars.


Author(s):  
Suk Yee Yong ◽  
Rachel L. Webster ◽  
Anthea L. King ◽  
Nicholas F. Bate ◽  
Matthew J. O’Dowd ◽  
...  

AbstractThe structure and kinematics of the broad line region in quasars are still unknown. One popular model is the disk-wind model that offers a geometric unification of a quasar based on the viewing angle. We construct a simple kinematical disk-wind model with a narrow outflowing wind angle. The model is combined with radiative transfer in the Sobolev, or high velocity, limit. We examine how angle of viewing affects the observed characteristics of the emission line. The line profiles were found to exhibit distinct properties depending on the orientation, wind opening angle, and region of the wind where the emission arises.At low inclination angle (close to face-on), we find that the shape of the emission line is asymmetric, narrow, and significantly blueshifted. As the inclination angle increases (close to edge-on), the line profile becomes more symmetric, broader, and less blueshifted. Additionally, lines that arise close to the base of the disk wind, near the accretion disk, tend to be broad and symmetric. Single-peaked line profiles are recovered for the intermediate and equatorial wind. The model is also able to reproduce a faster response in either the red or blue sides of the line profile, consistent with reverberation mapping studies.


2012 ◽  
Vol 372 ◽  
pp. 012069
Author(s):  
Andrea J Ruff ◽  
David J E Floyd ◽  
Kirk T Korista ◽  
Rachel L Webster ◽  
Ryan L Porter ◽  
...  

1997 ◽  
Vol 159 ◽  
pp. 175-178 ◽  
Author(s):  
Brian Espey

AbstractWe present a brief review of emission-line velocity differences, and describe an ongoing project to determine the driving mechanisms responsible. We conclude with a brief outline of the use of velocity differences as probes of the conditions in the nuclear region of AGNs.


2015 ◽  
Vol 812 (2) ◽  
pp. 99 ◽  
Author(s):  
Zhenzhen Li ◽  
Hongyan Zhou ◽  
Lei Hao ◽  
Huiyuan Wang ◽  
Tuo Ji ◽  
...  

2012 ◽  
Vol 754 (1) ◽  
pp. 18 ◽  
Author(s):  
Andrea J. Ruff ◽  
David J. E. Floyd ◽  
Rachel L. Webster ◽  
Kirk T. Korista ◽  
Hermine Landt

1997 ◽  
Vol 479 (1) ◽  
pp. 200-221 ◽  
Author(s):  
Mark Bottorff ◽  
Kirk T. Korista ◽  
Isaac Shlosman ◽  
Roger D. Blandford

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