S. Righini

The Simultaneous Medicina‐Planck Experiment: data acquisition, reduction and first results

ABSTRACT The Simultaneous Medicina-Planck Experiment (SiMPlE) is aimed at observinga selected sample of 263 extragalactic and Galactic sources with the Medicina 32-msingle dish radio telescope in the same epoch as the Planck satellite observations.The data acquired with a frequency coverage down to 5 GHz, also combined withPlanck at frequencies above 30 GHz, will constitute a useful reference catalogue ofbright sources over the whole Northern hemisphere. Furthermore, source observationsperformed in different epochs and comparison with other catalogues allow the inves-tigation of source variabilities on different timescales.In this work, we describe the sample selection, the on-going data acquisition cam-paign, the data reduction procedures, the developed tools, and the comparison withother data-sets.We present the data at 5 and 8.3 GHz for the SiMPlE Northern Sample consistingof 79 sources with δ > 45 ◦ selected in our catalogue and observed during the first6 months of the project. A first analysis of their spectral behaviour and long-termvariability is also presented.Keywords: galaxies: active – radio continuum: galaxies – radio continuum: general– cosmic microwave background.

Diving into the Sardinia Radio Telescope minor servo system

The Sardinia Radio Telescope (SRT) is a new 64-metre, Gregorian-shaped antenna built in Sardinia (Italy). It is designed to carry out observations up to 100 GHz. The telescope is provided with six focal positions: primary, Gregorian and four beam-waveguide foci. This paper describes the project of the servo system which allows the focus and receiver selection during the instrument setup. This system also operates, at the observation stage, the compensation of some of the stucture deformations due to gravity, temperature variations and other environmental effects. We illustrate the system features following a bottom-up approach, analysing all the project layers ranging from low-level systems, as the hardware controls, to the design and implementation of high-level software, which is based on the distributed objects ACS (ALMA Common Software) framework. Particular focus will be put on the links among the hierarchical levels of the system, and on the solutions adopted in order to guarantee that the control of the servo system is abstracted from the underlying hardware.

The control software for the Sardinia Radio Telescope

The Sardinia Radio Telescope (SRT) is a new 64-meter shaped antenna designed to carry out observations up to 100 GHz. This large instrument has been built in Sardinia, 35 km north of Cagliari, and is now facing the technical commissioning phase. This paper describes the architecture, the implementation solutions and the development status of NURAGHE, the SRT control software. Aim of the project was to produce a software which is reliable, easy to keep up to date and flexible against other telescopes. The most ambitious goal will be to install NURAGHE at all the three italian radio telescopes, allowing the astronomers to access these facilities through a common interface with very limited extra effort. We give a description of all the control software subsystems (servo systems, backends, receivers, etc.) focusing on the resulting design, which is based on the ACS (Alma Common Software) patterns and comes from linux-based, LGPL, Object-Oriented development technologies. We also illustrate how NURAGHE deals with higher level requirements, coming from the telescope management or from the system users.

Single-dish and VLBI observations of Cygnus X-3 during the 2016 giant flare episode

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 Telescope. Long observations were performed in order to follow the evolution of the flare on a hourly scale, covering six frequency ranges from 1.5 GHz to 25.6 GHz. The radio emission reached a maximum of 13.2 ± 0.7 Jy at 7.2 GHz and 10 ± 1 Jy at 18.6 GHz. Rapid flux variations were observed at high radio frequencies at the peak of the flare, together with rapid evolution of the spectral index: α steepened from 0.3 to 0.6 (with S

Imaging of SNR IC443 and W44 with the Sardinia Radio Telescope at 1.5 and 7 GHz

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FBQS J1644+2619 : multiwavelength properties and its place in the class of gamma-ray emitting Narrow Line Seyfert 1s

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Investigating the high-frequency spectral features of SNRs Tycho, W44 and IC443 with the Sardinia Radio Telescope

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An RFI mitigation project at the Italian radio telescopes

within 5 hours. This is the first time that such fast variations are observed, giving support to the evolution from optically thick to optically thin plasmons in expansion moving outward from the core. Based on the Italian network (Noto, Medicina and SRT) and extended to the European antennas (Torun, Yebes, Onsala), VLBI observations were triggered at 22 GHz on five different occasions, four times prior to the giant flare, and once during its decay phase. Flux variations of 2-hour duration were recorded during the first session. They correspond to a mini-flare that occurred close to the core ten days before the onset of the giant flare. From the latest VLBI observation we infer that four days after the flare peak the jet emission was extended over 30 mas.