267 citations · 2.1k across the 69 of their papers we have counts for
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VLT adaptive optics imaging of QSO host galaxies and close environment at z ~2.5: results from a pilot program
R. Falomo, J. K. Kotilainen, R. Scarpa +1
We report ESO-VLT near-infrared adaptive optics imaging of one radio-loud (PKS 0113-283) and two radio-quiet (Q 0045-3337 and Q 0101-337) QSOs at z > 2. In the first case, we are a…
Using globular clusters to test gravity in the weak acceleration regime: NGC 6171
Riccardo Scarpa, Gianni Marconi, Roberto Gilmozzi
As part of an ongoing program to test Newton's law of gravity in the low acceleration regime using globular clusters, we present here new results obtained for NGC 6171. Combining V…
H1517+656: the Birth of a BL Lac Object?
Matthew O'Dowd, C. Megan Urry, Riccardo Scarpa +2
H1517+656 is an unusual source, even for a BL Lac object. It is one of the most luminous BL Lacs known, with extreme emission properties at radio, optical, and X-ray frequencies. F…
The nature of close companions of the BL Lac Objects 1ES 0502+675 and 1ES 1440+122
G. Giovannini, R. Falomo, R. Scarpa +2
We report on deep radio images and optical spectroscopy of two BL Lac objects that have very close compact companions. The two targets, 1ES 0502+675 and 1ES 1440+122, were selected…
Jets from Sub-Parsec to Kiloparsec Scales: A Physical Connection
F. Tavecchio, L. Maraschi, R. M. Sambruna +4
The Chandra discovery of bright X-ray emission from kpc-scale jets allows insight into the physical parameters of the jet flow at large scale. At the opposite extreme, extensive st…