We study a recently observed gravitational microlensing peak in the V-band light curve of Q2237+0305A using a relatively simple physical model, but one that is...
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PublicationDetermination of the properties of the central engine in microlensed QSOs
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PublicationDetermining the fraction of reddened quasars in COSMOS with multiple selection techniques from X-ray to radio wavelengths
The sub-population of quasars reddened by intrinsic or intervening clouds of dust are known to be underrepresented in optical quasar surveys. By defining a...
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PublicationDiscovery of a binary quasar at z = 1.76
We present the serendipitous discovery of a physical pair of quasars with estimated cosmological redshift z = 1.76. Long-slit spectroscopic observations of the...
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NewsDiscovery of relativistic jets blowing bubbles in the central region of the Teacup Galaxy
A study led by Anelise Audibert, a researcher at the Instituto de Astrofísica de Canarias (IAC), reveals a process that explains the peculiar morphology of the...
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PublicationDiscovery of Very High Energy γ-Rays from 1ES 1011+496 at z = 0.212
We report on the discovery of very high energy (VHE) γ-ray emission from the BL Lacertae object 1ES 1011+496. The observation was triggered by an optical...
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PublicationDo the Most Massive Black Holes at z = 2 Grow via Major Mergers?
The most frequently proposed model for the origin of quasars holds that the high accretion rates seen in luminous active galactic nuclei (AGN) are primarily...
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PublicationDramatic emission line variations in QSO KAZ 102 and possible causes
We report optical spectroscopic observations of the radio-quiet quasar Kaz 102. We find impressive variations of the Hα emission line both in shape and...
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PublicationDust Reverberation Mapping in Distant Quasars from Optical and Mid-infrared Imaging Surveys
The size of the dust torus in active galactic nuclei (AGNs) and their high-luminosity counterparts, quasars, can be inferred from the time delay between UV...
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PublicationEight more ultra luminous X-ray candidates unmasked
Aims:We aim to identify the nature of several objects previously catalogued as ultra-luminous X-ray (ULX) source candidates. Methods: Long-slit spectroscopy of...