135 citations · 1.3k across the 49 of their papers we have counts for
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RadioAstron Space VLBI Imaging of the jet in M87: I. Detection of high brightness temperature at 22 GHz
Jae-Young Kim, Tuomas Savolainen, Petr Voitsik +19
We present results from the first 22 GHz space very-long-baseline interferometric (VLBI) imaging observations of M87 by RadioAstron. As a part of the Nearby AGN Key Science Program…
The WISSH quasars project X. Discovery of a multi-component and highly-variable UV ultra-fast outflow in a z=3.6 quasar
G. Vietri, T. Misawa, E. Piconcelli +16
We report on the variability of a multi-component broad absorption line (BAL) system observed in the hyper-luminous quasar J1538+0855 at z=3.6. Observations from SDSS, VLT, LBT and…
First Space-VLBI Observations of Sagittarius A*
Michael D. Johnson, Yuri Y. Kovalev, Mikhail M. Lisakov +3
We report results from the first Earth-space VLBI observations of the Galactic Center supermassive black hole, Sgr A*. These observations used the space telescope Spektr-R of the R…
Polarimetric properties of Event Horizon Telescope targets from ALMA
Ciriaco Goddi, Ivan Marti-Vidal, Hugo Messias +31
We present the results from a full polarization study carried out with ALMA during the first VLBI campaign, which was conducted in Apr 2017 in the 3mm and 1.3mm bands, in con…
RadioAstron reveals a spine-sheath jet structure in 3C 273
G. Bruni, J. L. Gómez, L. Vega-García +13
We present Space-VLBI RadioAstron observations at 1.6 GHz and 4.8 GHz of the flat spectrum radio quasar 3C 273, with detections on baselines up to 4.5 and 3.3 Earth Diameters, resp…
The WISSH QSOs project IX. Cold gas content and environment of luminous QSOs at z~2.4-4.7
M. Bischetti, C. Feruglio, E. Piconcelli +23
Sources at the brightest end of QSO luminosity function during the peak epoch of star formation and black hole accretion (z~2-4, i.e. Cosmic noon) are privileged sites to study the…
Hard - X-rays selected Active Galactic Nuclei. I. A radio view at high-frequencies
E. Chiaraluce, F. Panessa, G. Bruni +5
A thorough study of radio emission in Active Galactic Nuclei (AGN) is of fundamental importance to understand the physical mechanisms responsible for the emission and the interplay…
Multiband RadioAstron space VLBI imaging of the jet in quasar S5 0836+710
L. Vega-García, A. P. Lobanov, M. Perucho +11
Detailed studies of relativistic jets in active galactic nuclei (AGN) require high-fidelity imaging at the highest possible resolution. This can be achieved using very long baselin…
Active galactic nuclei imaging programs of the RadioAstron mission
Gabriele Bruni, Tuomas Savolainen, Jose Luis Gómez +2
Imaging relativistic jets in active galactic nuclei (AGN) at angular resolution significantly surpassing that of the ground-based VLBI at centimetre wavelengths is one of the key s…
From radio-quiet to radio-silent: low luminosity Seyfert radio cores
E. Chiaraluce, G. Bruni, F. Panessa +5
A strong effort has been devoted to understand the physical origin of radio emission from low-luminosity AGN (LLAGN), but a comprehensive picture is still missing. We used high-res…
Probing restarting activity in hard X-ray selected giant radio galaxies
G. Bruni, F. Ursini, F. Panessa +13
With their sizes larger than 0.7 Mpc, Giant Radio Galaxies (GRGs) are the largest individual objects in the Universe. To date, the reason why they reach such enormous extensions is…
A wide and collimated radio jet in 3C 84 on the scale of a few hundred gravitational radii
G. Giovannini, T. Savolainen, M. Orienti +22
Understanding the launching, acceleration, and collimation of jets powered by active galactic nuclei remains an outstanding problem in relativistic astrophysics. This is partly bec…
Broadband radio spectro-polarimetric observations of high Faraday rotation measure AGN
Alice Pasetto, Carlos Carrasco-González, Shane O'Sullivan +5
We present broadband polarimetric observations of a sample of high Faraday rotation measure (RM) AGN using the VLA telescope from 1 to 2 GHz, and 4 to 12 GHz. The sample (14 source…
FERMI transient J1544-0649: a flaring radio-weak BL Lac
G. Bruni, F. Panessa, G. Ghisellini +6
On May 15th, 2017, the \emph{FERMI}/LAT gamma-ray telescope observed a transient source not present in any previous high-energy catalogue: J1544-0649. It was visible for two consec…
Probing the innermost regions of AGN jets and their magnetic fields with RadioAstron II. Observations of 3C 273 at minimum activity
G. Bruni, J. L. Gómez, C. Casadio +18
RadioAstron is a 10 m orbiting radio telescope mounted on the Spektr-R satellite, launched in 2011, performing Space Very Long Baseline Interferometry (SVLBI) observations supporte…
A multi-wavelength continuum characterization of high-redshift broad absorption line quasars
D. Tuccillo, G. Bruni, M. A. DiPompeo +5
We present the results of a multi-wavelength study of a sample of high-redshift Radio Loud (RL) Broad Absorption Line (BAL) quasars. This way we extend to higher redshift previous…
JVLA Wideband Polarimetry Observations on a Sample of High Rotation Measure Sources
Alice Pasetto, Carlos Carrasco-González, Gabriele Bruni +4
We present preliminary results of JVLA wideband full polarization observations of a sample of Active Galactic Nuclei (AGN) with very high Rotation Measure (RM) values, a sign of ex…
A possible link between high rotation measure and CSS-GPS sources
Alice Pasetto, Alex Kraus, Karl-Heinz Mack +2
We report here the study, in the radio band, of a sample of candidates of high Rotation Measure (RM). The point-like objects (at kpc scale) were selected by choosing unpolarised so…
A study of a sample of high rotation measure AGNs through multifrequency single dish observations
Alice Pasetto, Alex Kraus, Karl-Heinz Mack +2
We characterised and studied, in the radio band, a sample of candidates of high Rotation Measure (RM). These point-like objects show a strong depolarisation at 21cm. This feature s…
Restarting radio activity and dust emission in radio-loud broad absorption line quasars
G. Bruni, K. -H. Mack, F. M. Montenegro-Montes +2
Broad absorption line quasars (BAL QSOs) are objects showing absorption from relativistic outflows, with velocities up to 0.2c. These manifest, in about 15% of quasars, as absorpti…
RadioAstron space VLBI imaging of polarized radio emission in the high-redshift quasar 0642+449 at 1.6 GHz
A. P. Lobanov, J. L. Gómez, G. Bruni +8
Polarization of radio emission in extragalactic jets at a sub-milliarcsecond angular resolution holds important clues for understanding the structure of the magnetic field in the i…
Investigating the radio-loud phase of broad absorption line quasars
G. Bruni, J. I. González-Serrano, M. Pedani +5
Broad absorption lines (BALs) are present in the spectra of ~20% of quasars (QSOs); this indicates fast outflows (up to 0.2c) that intercept the observer's line of sight. These QSO…
The central structure of Broad Absorption Line QSOs: observational characteristics in the cm-mm wavelength domain
G. Bruni, K. -H. Mack, D. Dallacasa +6
Accounting for ~20% of the total QSO population, Broad Absorption Line QSOs are still an unsolved problem in the AGN context. They present wide troughs in the UV spectrum, due to m…