Gravitationally lensed QSOs in the ISSIS/WSO-UV era

et al. 2011

ApJ

We present the results of our X-ray, UV and optical monitoring campaign of the first gravitationally lensed AGN from late 2009 to mid 2010. The trailing (B) image of the AGN 0957+561 shows the intrinsic continuum variations that were predicted in advance based on observations of the leading (A) image in the gr optical bands. This multiwavelength variability of the B image allows us to carry out a reverberation mapping analysis in the radio-loud AGN 0957+561 at redshift z = 1.41. We find that the U -band and r-band light curves are highly correlated with the g-band record, leading and trailing it by 3 ± 1 days (U band) and 4 ± 1 days (r band). These 1σ measurements are consistent with a scenario in which flares originated in the immediate vicinity of the supermassive black hole are thermally reprocessed in a standard accretion disk at ∼ 10-20 Schwarzschild radii from the central dark object. We also report that the light curve for the X-ray emission with power-law spectrum is delayed with respect to those in the U gr bands by ∼ 32 days. Hence, the central driving source can not be a standard corona emitting the observed power-law X-rays. This result is also supported by X-ray reprocessing simulations and the absence of X-ray reflection features in the spectrum of 0957+561. We plausibly interpret the lack of reflection and the 32-day delay as evidence for a power-law X-ray source in the base of the jet at a typical height of ∼ 200 Schwarzschild radii. A central EUV source would drive the variability of 0957+561.

Section: Introductionmentioning

confidence: 84%

Accretion Onto the Supermassive Black Hole in the High-Redshift Radio-Loud Agn 0957+561

Gil-Merino

et al. 2011

ApJ

“…We belong to the WSO-UV/ISSIS Science Working Group, and are involved in the preparation of a large observation program to analyse optically-bright lensed quasars in the UV (Goicoechea et al 2011) 2 . In more detail, using the CASTLES 3 and SQLS 4 databases, we selected 41 systems in the redshift interval 1 < z < 3.…”

Section: Discussionmentioning

confidence: 99%

Crowded-field image simulator for WSO-UV/ISSIS: first functional version developed by the Glendama team

2014

Astrophys Space Sci

Self Cite

We are developing a web-based interactive software to simulate crowded-field imaging with ISSIS on board the future WSO-UV. This new tool is aimed to prepare WSO-UV/ISSIS proposals to observe multicomponent targets and dense fields. For a given combination of UV channel, filters and exposure time, the user creates a set of point-like and extended sources (source model). This source model produces a final image, which takes into account a pixelated field of view, a realistic conversion between physical flux and counts per second, the convolution with the expected point spread function, a sky background and noise fluctuations. The current version of the simulator is available at the Glendama website, and it allows users to specify all relevant parameters of each point-like or extended source, drag-and-drop sources by using a mouse or a fingertip/stylus on a touchscreen, change the frame size or the brightness scale, etc.

“…First, by visual inspection of the brightness records, we found that the magnitudes of A and B strongly deviate from adjacent data. Deviations of A and B occur in the same direction 5 All pre-processed frames will be soon publicly available on the GLENDAMA archive at http://grupos.unican.es/glendama/ database/ (Goicoechea et al 2015) 6 Other PSF stars led to similar results or in opposite directions (likely due to crosstalk between both images), and exceed by more than three times the preliminary typical errors. Second, a careful data analysis indicated that either the PSF fitting of the lens system led to a large χ 2 value, the image quality was poor or both things hapenned.…”

Section: Light Curves In the R Bandmentioning

confidence: 99%

Gravitational lens system SDSS J1339+1310: microlensing factory and time delay

2016

A&A

Self Cite

We spectroscopically re-observed the gravitational lens system SDSS J1339+1310 using OSIRIS on the GTC. We also monitored the r-band variability of the two quasar images (A and B) with the LT over 143 epochs in the period 2009−2016. These new data in both the wavelength and time domains have confirmed that the system is an unusual microlensing factory. The C iv emission line is remarkably microlensed, since the microlensing magnification of B relative to that for A, µ BA , reaches a value of 1.4 (∼ 0.4 mag) for its core. Moreover, the B image shows a red wing enhancement of C iv flux (relative to A), and µ BA = 2 (0.75 mag) for the C iv broad-line emission. Regarding the nuclear continuum, we find a chromatic behaviour of µ BA , which roughly varies from ∼ 5 (1.75 mag) at 7000 Å to ∼ 6 (1.95 mag) at 4000 Å. We also detect significant microlensing variability in the r band, and this includes a number of microlensing events on timescales of 50−100 d. Fortunately, the presence of an intrinsic 0.7 mag dip in the light curves of A and B, permitted us to measure the time delay between both quasar images. This delay is ∆t AB = 47 +5 −6 d (1σ confidence interval; A is leading), in good agreement with predictions of lens models.