Publications (36)
A complete sample of GHz-Peaked-Spectrum radio sources and its radio properties
C. Stanghellini, C. P. O'Dea, D. Dallacasa +3
We define a complete sample of thirty-three GHz-Peaked-Spectrum (GPS) radio sources based on their spectral properties. We present measurements of the radio spectra and polarizatio…
VLBA observations of GHz-Peaked-Spectrum radio sources at 15 GHz
C. Stanghellini, D. Dallacasa, C. P. O'Dea +3
We present VLBA observations at 15 GHz of ten GHz Peaked Spectrum (GPS) radio sources. The cores are often difficult or impossible to locate. When likely cores are found, they acco…
LFVN observations of active galactic nuclei
A. Pushkarev, I. Molotov, M. Nechaeva +7
In November 1999 we carried out VLBI observations of several quasars and BL Lacertae objects at 1.66 GHz. Six antennas participated in the experiment (Bear Lakes, Svetloe, Pushchin…
The hard X-ray view of Giga-Hertz Peaked Spectrum Radio Galaxies
M. Guainazzi, A. Siemiginowska, C. Stanghellini +3
We present the first broadband X-ray observations of four Giga-Hertz Peaked Spectrum (GPS) radio galaxies at redshift <~1 performed by Chandra and XMM-Newton. These observations mo…
VLBA images of High Frequency Peakers
M. Orienti, D. Dallacasa, S. Tinti +1
We propose a morphological classification based on the parsec scale structure of fifty-one High Frequency Peakers (HFPs) from the ``bright'' HFP sample. VLBA images at two adjacent…
Radio monitoring of a sample of X- and gamma-ray loud blazars
T. Venturi, D. Dallacasa, A. Orfei +7
In this paper we present the results of a 4-year (1996 - 1999) radio flux density monitoring program for a sample of X- and -ray loud blazars. Our program started in January 19…
Faint -ray sources at low-redshift: the radio galaxy IC 1531
T. Bassi, G. Migliori, P. Grandi +6
We present a multi-wavelength study of IC 1531 (z=0.02564), an extragalactic radio source associated with the -ray object 3FGL J0009.9-3206 and classified as a blazar of uncert…
The Sardinia Radio Telescope: From a Technological Project to a Radio Observatory
I. Prandoni, M. Murgia, A. Tarchi +43
[Abridged] The Sardinia Radio Telescope (SRT) is the new 64-m dish operated by INAF (Italy). Its active surface will allow us to observe at frequencies of up to 116 GHz. At the mom…
High Frequency Peakers: Baby Radio Sources?
S. Tinti, D. Dallacasa, G. De Zotti +2
We present the results of second epoch simultaneous multifrequency observations of 45 sources out of the 55 in the sample of High Frequency Peakers (HFP) by Dallacasa et al. (2000)…
An X-ray view of Pictor A radio lobes: a spatially resolved study
G. Migliori, P. Grandi, G. C. G. Palumbo +2
A spatially resolved analysis of the lobes of the radio galaxy Pictor A has been performed for the first time starting from a 50 ksec XMM-Newton observation. Magnetic field, B_{IC}…
The high brightness temperature of B0529+483 revealed by RadioAstron and implications for interstellar scattering
S. V. Pilipenko, Y. Y. Kovalev, A. S. Andrianov +22
The high brightness temperatures, K, detected in several active galactic nuclei by RadioAstron space VLBI observations challenge theoretical limits. R…
Bright OB stars in the Galaxy - III. Constraints on the radial stratification of the clumping factor in hot star winds from a combined Halpha, IR and radio analysis
J. Puls, N. Markova, S. Scuderi +4
Recent results strongly challenge the canonical picture of massive star winds: various evidence indicates that currently accepted mass-loss rates, Mdot, may need to be revised down…
Extended emission around GPS radio sources
C. Stanghellini, C. P. O'Dea, D. Dallacasa +4
Extended radio emission detected around a sample of GHz Peaked Spectrum (GPS) radio sources is discussed. Evidence for extended emission which is related to the GPS source is found…
The Compton-thick AGN in the GPS radio source OQ+208
M. Guainazzi, C. Stanghellini, P. Grandi
We report in this paper the ASCA discovery of the first radio-loud Active Galactic Nucleus (AGN) covered by a Compton-thick X-ray absorber, in the GigaHertz Peaked Spectrum (GPS) r…
Drilled by the jet? XMM-Newton discovers a Compton-thick AGN in the GPS galaxy Mkn668
M. Guainazzi, A. Siemiginowska, P. Rodriguez-Pascual +1
We report the XMM-Newton discovery of the first Compton-thick obscured AGN in a Broad Line Radio Galaxy, the Gigahertz Peaked-Spectrum source Mkn668 (OQ+208). The remarkably flat 2…
Spectral variability in faint high frequency peakers
M. Orienti, D. Dallacasa, C. Stanghellini
We present the analysis of simultaneous multi-frequency Very Large Array (VLA) observations of 57 out of 61 sources from the ``faint'' high frequency peaker (HFP) sample carried ou…
A Search for Molecular Gas in GHz Peaked Spectrum Radio Sources
C. P. O'Dea, J. Gallimore, C. Stanghellini +2
We present searches for molecular gas (CO, OH, CS, and Ammonia) in six GHz Peaked Spectrum (GPS) radio sources. We do not detect gas in any source and place upper limits on the mas…
An International Survey of Front-End Receivers and Observing Performance of Telescopes for Radio Astronomy
P. Bolli, A. Orfei, A. Zanichelli +18
This paper presents a survey of microwave front-end receivers installed at radio telescopes throughout the World. This unprecedented analysis was conducted as part of a review of f…
The B3-VLA CSS sample. VIII: New optical identifications from the Sloan Digital Sky Survey. The ultraviolet-optical spectral energy distribution of the young radio sources
C. Fanti, R. Fanti, A. Zanichelli +2
Compact steep-spectrum radio sources and giga-hertz peaked spectrum radio sources (CSS/GPS) are generally considered to be mostly young radio sources. In recent years we studied at…
A sample of small size compact steep-spectrum radio sources. VLBI images and VLA polarization at 5 GHz
D. Dallacasa, M. Orienti, C. Fanti +2
Global VLBI observations at 5 GHz have been performed to study the source morphology in 10 compact steep-spectrum (CSS) sources selected from the Peacock & Wall catalogue with the…
Optical identifications of High Frequency Peakers
D. Dallacasa, R. Falomo, C. Stanghellini
We present CCD observations of 13 objects from a complete sample of 55 bright High Frequency Peaker (HFP) radio sources, and provide optical identification for 12 of them. Images i…
ISO observations of a sample of Compact Steep Spectrum and GHz Peaked Spectrum Radio Galaxies
C. Fanti, F. Pozzi, R. Fanti +13
We present results from observations obtained with ISOPHOT, on board the ISO satellite, of a representative sample of seventeen CSS/GPS radio galaxies and of a control sample of si…
The B3-Vla CSS sample. III: Evn & Merlin images at 18 cm
D. Dallacasa, C. Fanti, S. Giacintucci +4
EVN and MERLIN observations at 18 cm are presented for 18 Compact Steep--spectrum radio Sources (CSSs) from the B3-VLA CSS sample. These sources were marginally resolved in previou…
Radio Lobes of Pictor A: an X-ray spatially resolved Study
G. Migliori, P. Grandi, G. G. C. Palumbo +2
A new XMM observation has made possible a detailed study of both lobes of the radio galaxy Pictor A. Their X-ray emission is of non thermal origin and due to Inverse Compton scatte…
Constraining the spectral age of very asymmetric CSOs
M. Orienti, D. Dallacasa, C. Stanghellini
We constrain the spectral ages for two very asymmetric Compact Symmetric Objects (CSO) from the B3-VLA-CSS sample, and we investigate the role of the ambient medium potentially abl…
Constraining the nature of High Frequency Peakers. I. The spectral variability
M. Orienti, D. Dallacasa, C. Stanghellini
We investigate the spectral characteristics of 51 candidate High Frequency Peakers (HFPs), from the ``bright'' HFP sample, in order to determine the nature of each object, and to o…
Bendings of radio jets in BL Lacertae objects I: EVN and MERLIN observations
P. Cassaro, C. Stanghellini, D. Dallacasa +2
Several blazars, and BL Lac objects in particular, show a misalignment between the jet orientation on parsec and kiloparsec scales. Some authors (i.e. Conway & Murphy, 1993) have a…
NGC 3894: a young radio galaxy seen by Fermi-LAT
G. Principe, G. Migliori, T. J. Johnson +7
Context. According to radiative models, radio galaxies may produce gamma-ray emission from the first stages of their evolution. However, very few such galaxies have been detected b…
Extended radio emission in BL Lac objects - I: the images
P. Cassaro, C. Stanghellini, M. Bondi +3
We have observed 28 sources selected from the 1Jy sample of BL Lac objects (Stickel et al. 1991) with the Very Large Array (VLA) in A, B and D configurations at 1.36, 1.66 and 4.85…
Multi-wavelength flare observations of the blazar S5 1803+784
R. Nesci, S. Cutini, C. Stanghellini +8
The radio, optical, and -ray light curves of the blazar S5 1803+784, from the beginning of the {\it Fermi} Large Area Telescope (LAT) mission in August 2008 until December 2018…
SKAVLBI view of AGN jets in the early Universe
C. Spingola, M. Mezcua, Y. Liu +33
Active Galactic Nuclei (AGN) are among the brightest sources in the Universe, and those that are also jetted are uniquely valuable at the earliest epochs, because their relativisti…
High Frequency Peakers: young radio sources or flaring blazars?
S. Tinti, D. Dallacasa, G. De Zotti +2
We present new, simultaneous, multifrequency observations of 45 out of the 55 candidate High Frequency Peakers (HFP) selected by Dallacasa et al. (2000), carried out 3 to 4 years a…
Single-dish and VLBI observations of Cygnus X-3 during the 2016 giant flare episode
E. Egron, A. Pellizzoni, M. Giroletti +34
In September 2016, the microquasar Cygnus X-3 underwent a giant radio flare, which was monitored for 6 days with the Medicina Radio Astronomical Station and the Sardinia Radio Tele…
The B3-VLA CSS sample. II: VLBA images at 18 cm
D. Dallacasa, S. Tinti, C. Fanti +4
VLBA observations at 18 cm are presented for 28 Compact Steep-spectrum radio Sources (CSSs) from the B3-VLA CSS sample. These sources were unresolved in previous VLA observations a…
The atmospheric fragmentation of the 1908 Tunguska Cosmic Body: reconsidering the possibility of a ground impact
L. Foschini, L. Gasperini, C. Stanghellini +3
The 1908 June 30 Tunguska Event (TE) is one of the best studied cases of cosmic body impacting the Earth with global effects. However, still today, significant doubts are casted on…
Jetted subgalactic-size radio sources in merging galaxies -- A jet redirection scenario
C. Stanghellini, M. Orienti, C. Spingola +6
Context: The long-standing question concerning jetted subgalactic-size (JSS) radio sources is whether they will evolve into large radio galaxies, die before escaping the host galax…