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Register a new userImage Flux Ratios of Gravitationally Lensed HS 0810+2554 with High Resolution Infrared Imaging
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We report near simultaneous imaging using LMIRCam on the LBTI of the quadruply imaged lensed quasar HS 0810+2554 at wavelengths of 2.16, 3.7 and $4.78~mu$m with a Full Width Half Max (FWHM) spatial resolution of $0^{primeprime}!!.13$, $0^{primeprime}!!.12$ and $0^{primeprime}!!.15$ respectively, comparable to HST optical imaging. In the $rm{z} = 1.5$ rest frame of the quasar, the observed wavelengths correspond to 0.86, 1.48, and $1.91~mu$m respectively. The two brightest images in the quad, A and B, are clearly resolved from each other with a separation of $0.187^{primeprime}$. The flux ratio of these two images (A/B) trends from 1.79 to 1.23 from 2.16 to $4.78~mu$m. The trend in flux ratio is consistent with the $2.16~mu$m flux originating from a small sized accretion disk in the quasar that experiences only microlensing. The excess flux above the contribution from the accretion disk at the two longer wavelengths originates from a larger sized region that experiences no microlensing. A simple model employing multiplicative factors for image B due to stellar microlensing $(m)$ and sub-structure millilensing $(M)$ is presented. The result is tightly constrained to the product $mtimes M=1.79$. Given the observational errors, the 60% probability contour for this product stretches from $m= 2.6$, $M = 0.69$ to $m= 1.79$, $M = 1.0$, where the later is consistent with microlensing only.
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We present results from X-ray observations of the gravitationally lensed z = 1.51 AGN HS 0810+2554 performed with the Chandra X-ray Observatory and XMM-Newton. Blueshifted absorption lines are detected in both observations at rest-frame energies ranging between ~1-12 keV at > 99% confidence. The inferred velocities of the outflowing components range between ~0.1c and ~0.4c. A strong emission line at ~6.8 keV accompanied by a significant absorption line at ~7.8 keV is also detected in the Chandra observation. The presence of these lines is a characteristic feature of a P-Cygni profile supporting the presence of an expanding outflowing highly ionized iron absorber in this quasar. Modeling of the P-Cygni profile constrains the covering factor of the wind to be > 0.6, assuming disk shielding. A disk-reflection component is detected in the XMM-Newton observation accompanied by blueshifted absorption lines. The XMM-Newton observation constrains the inclination angle to be < 45 degrees at 90% confidence, assuming the hard excess is due to blurred reflection from the accretion disk. The detection of an ultrafast and wide-angle wind in an AGN with intrinsic narrow absorption lines (NALs) would suggest that quasar winds may couple efficiently with the intergalactic medium and provide significant feedback if ubiquitous in all NAL and BAL quasars. We estimate the mass-outflow rate of the absorbers to lie in the range of 1.5 and 3.4 Msolar/yr for the two observations. We find the fraction of kinetic to electromagnetic luminosity released by HS 0810+2554 is large (epsilon = 9 (-6,+8)) suggesting that magnetic driving is likely a significant contributor to the acceleration of this outflow.
We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the quadruply lensed z=1.51 quasar HS 0810+2554 which provide useful insight on the kinematics and morphology of the CO molecular gas and the ~2 mm continuum emission in the quasar host galaxy. Lens modeling of the mm-continuum and the spectrally integrated CO(3-2) images indicates that the source of the mm-continuum has an eccentricity of e~0.9 with a size of ~1.6 kpc and the source of line emission has an eccentricity of e~0.7 with a size of ~1 kpc. The spatially integrated emission of the CO(2-1) and CO(3-2) lines shows a triple peak structure with the outer peaks separated by Dv_21 = 220 +- 19 km s^-1 and Dv_32 = 245 +/- 28 km s^-1, respectively, suggesting the presence of rotating molecular CO line emitting gas. Lensing inversion of the high spatial resolution images confirms the presence of rotation of the line emitting gas. Assuming a conversion factor of alpha_CO = 0.8 M_solar (K km s^-1 pc^2)^-1 we find the molecular gas mass of HS 0810+2554 to be M _ Mol = [(5.2 +/- 1.5)/mu_32] x10^10 M_solar, where mu_32 is the magnification of the CO(3-2) emission. We report the possible detection, at the 3.0 - 4.7 sigma confidence level, of shifted CO(3-2) emission lines of high-velocity clumps of CO emission with velocities up to 1702 km s^-1. We find that the momentum boost of the large scale molecular wind is below the value predicted for an energy-conserving outflow given the momentum flux observed in the small scale ultrafast outflow.
We present results from an observation of the gravitationally lensed z=1.51 narrow absorption line AGN HS 0810+2554 performed with the Chandra X-ray Observatory. The factor of ~100 lensing magnification of HS 0810+2554 makes this source exceptionally bright. Absorption lines are detected at rest-frame energies of ~ 7.7 keV and ~11.0 keV at >97% significance. By interpreting these lines to arise from highly ionized iron the implied outflow velocities of the X-ray absorbing gas corresponding to these lines are 0.13c and 0.41c, respectively. The presence of these relativistic outflows and the absence of any significant low-energy X-ray absorption suggest that a shielding gas is not required for the generation of the relativistic X-ray absorbing winds in HS 0810+2554. UV spectroscopic observations with VLT/UVES indicate that the UV absorbing material is outflowing at v_UV ~0.065c. Our analysis indicates that the fraction of the total bolometric energy released by HS 0810+2554 into the IGM in the form of kinetic energy is epsilon_k = 1.0(-0.6,+0.8). An efficiency of greater than unity implies that magnetic driving is likely a significant contributor to the acceleration of this X-ray absorbing wind. We also estimate the mass-outflow rate of the strongest absorption component to be Mdot_abs=1.1(-0.7,+0.9) M_solar yr^-1. Assuming that the energetic outflow detected in the NAL AGN HS 0810+2554 is a common property of most AGN it would suggest that the X-ray absorbing wind may have a larger opening angle than previously thought. This has important consequences for estimating the feedback contribution of X-ray absorbing winds to the surrounding IGM.
The jets image modelling of gravitationally lensed sources have been performed. Several basic models of the lens mass distribution were considered, in particular, a singular isothermal ellipsoid, an isothermal ellipsoid with the core, different multi-components models with the galactic disk, halo and bulge. The obtained jet images were compared as with each other as with results of observations. A significant dependence of the Hubble constant on the model parameters was revealed for B0218+357, when the circular structure was took into account.
We present new HST WFPC3 imaging of four gravitationally lensed quasars: MG 0414+0534; RXJ 0911+0551; B 1422+231; WFI J2026-4536. In three of these systems we detect wavelength-dependent microlensing, which we use to place constraints on the sizes and temperature profiles of the accretion discs in each quasar. Accretion disc radius is assumed to vary with wavelength according to the power-law relationship $rpropto lambda^p$, equivalent to a radial temperature profile of $Tpropto r^{-1/p}$. The goal of this work is to search for deviations from standard thin disc theory, which predicts that radius goes as wavelength to the power $p=4/3$. We find a wide range of power-law indices, from $p=1.4^{+0.5}_{-0.4}$ in B 1422+231 to $p=2.3^{+0.5}_{-0.4}$ in WFI J2026-4536. The measured value of $p$ appears to correlate with the strength of the wavelength-dependent microlensing. We explore this issue with mock simulations using a fixed accretion disc with $p=1.5$, and find that cases where wavelength-dependent microlensing is small tend to under-estimate the value of $p$. This casts doubt on previous ensemble single-epoch measurements which have favoured low values using samples of lensed quasars that display only moderate chromatic effects. Using only our systems with strong chromatic microlensing we prefer $p>4/3$, corresponding to shallower temperature profiles than expected from standard thin disc theory.
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