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We thank the referees for helping us improve the paper. The Sardinia Radio Telescope is funded by the Italian Ministry of University and Research (MUR), Italian Space Agency (ASI), and the Autonomous Region of Sardinia (RAS). The Medicina radio telescope is funded by the Italian Ministry of University and Research. Both radio telescopes are operated as National Facilities by the National Institute for Astrophysics (INAF). The Enhancement of the Sardinia Radio Telescope (SRT) for the study of the Universe at high radio frequencies is financially supported by the National Operative Program (Programma Operativo Nazionale - PON) of the Italian Ministry of University and Research "Research and Innovation 2014-2020", Notice D.D. 424 of 28/02/2018 for the granting of funding aimed at strengthening research infrastructures, in implementation of the Action II.1 – Project Proposal PIR01_00010. S. Mulas acknowledges contribution from Italian Space Agency for grant supports ASI/Cagliari University no. 2019-13-HH.0 and no. 2020-34-HH.0 “Studio per lo sviluppo scientifico nell’ambito dell’impiego del Sardinia Radio Telescope in configurazione SDSA, e in configurazione per radioastronomia in collaborazione con l’INAF, per la radioscienza e le osservazioni solari finalizzate ad applicazioni di Space Weather e Fisica Fondamentale”., This technical note describes SUNPIT (SUNdish PIpeline Tool) - the pipeline aimed at the imaging procedure and the data analysis of the radio solar data - and guides the user to properly reduce and analyse the solar data. SUNPIT is designed for radio data acquired with some radio telescopes of the INAF Network: the Sardinia Radio Telescope (SRT), and the Medicina Radio Telescope. The present user manual follows the development of software for solar imaging and data analysis of Active Regions (ARs), performed in the framework of the INAF Proposal "SunDish Project" (PI: A. Pellizzoni). This project has been active since 2018 with the goal of monitoring the solar atmosphere at high radio frequencies (at present 18 - 26 GHz) through single-dish observations. These solar observations will be enhanced through the upgrading of SRT with the new cryogenically cooled receivers, including a 19-feed in Q-band (33 - 50 GHz) and a 16-feed in W-band (75 - 116 GHz), in the context of the National Operative Programme (Programma Operativo Nazionale-PON); this project will provide in the near future an upgrading with the new receivers up to 116 GHz also for the Medicina and Noto Radio Telescopes, to provide the scientific community with the instrumentation suited to the study of the Universe at high radio frequencies. SUNPIT will be suitable for the data of these new forthcoming receivers, when available for the scientific community. SUNPIT produces a complete analysis of a solar map in about one hour, saving a directory which contains images, plots and several tables with the physical information of the solar disk and ARs (brightness temperatures, fluxes and spectral indices, with the respective errors). This pipeline – successfully tested – represents a crucial tool (1) to analyse solar images observed with the radio telescopes of the INAF Network, and (2) for the Space Weather monitoring network and forecast (soon available) along the solar cycle.

This technical note describes the Python package SUNDARA (SUNDish Active Region Analyser), a sophisticated code - fully self-consistent - aimed at the data analysis of solar images. This analysis is crucial for the INAF Proposal "SunDish Project" (PI: A. Pellizzoni), active since 2018 and devoted to imaging and monitoring the solar atmosphere at high radio frequencies (at present 18 - 26 GHz) through single-dish observations with INAF radio telescopes (SRT and Medicina). SUNDARA, characterised by a very user-friendly widget, allows to automatically unearth Active Regions (ARs) across the solar disk (or on its edge) through several algorithms; these ARs are modelled through an elliptical 2D-Gaussian kernel. In little more than 5 minutes, SUNDARA produces a complete analysis of a solar map, saving a directory containing images, plots and several tables with physical information of the solar disk and ARs (brightness temperatures, fluxes and spectral indices, with respective errors). A deeper analysis (that can be completed in a few hours) is possible thanks to a Bayesian approach based on Markov Chain MonteCarlo (MCMC) simulations. Moreover, these identified ARs are automatically associate in position with the detected ARs at other observing frequencies, reported in the Heliophysics Event Knowledgebase (HEK) used by the astrophysics and solar physics communities. SUNDARA has been successfully tested on a large amount of data from solar maps implemented with the radio telescopes of the INAF Network. For the purposes of this technical note, we report only two cases (one for Medicina, and one for SRT). This Python package constitutes a crucial tool for the INAF Network to analyse solar images (the Space Weather monitoring network and forecast along the solar cycle will be soon available), and to provide a complete overview of the astrophysical phenomena.

Solar observations offer both a rich interdisciplinary laboratory on fundamental astrophysics and precious tools for Space Weather applications. The involved plasma processes determine a complex radio emission picture that could be efficiently explored through single-dish imaging at high frequencies. In particular, mapping the brightness temperature of the free-free radio emission in the centimetre and millimetre range is an effective tool to characterise the vertical structure of the solar atmosphere. We are performing continuum imaging of the solar chromosphere in K-band (18-26.5 GHz, spatial resolution ∼ 1 arcmin) with the 32-m diameter Medicina radio telescope and with the 64-m diameter Sardinia Radio Telescope (SRT), as a first scientific demonstration test for the potentialities of Italian single-dish antennas in this field. This will also be useful for the assessment of observation parameters aiming at studying in detail the chromospheric brightness temperature of the quiet Sun, the solar flares, active regions and the sunspots, at high radio frequencies. These early observations proved that our antennas and K-band receivers are stable during solar pointing and could provide full mapping of the solar disk in ∼ 1 hour exposure using state-of-the-art imaging techniques.

The Sardinia Radio Telescope, which was inaugurated in 2013, is getting ready to participate in the Search for ExtraTerrestrial Intelligence (SETI) observations. This involves, in collaboration with the SETI collaboration and the ``Breakthrough Listen initiative", the onsite installation of the SERENDIP VI setup for SETI observations. In parallel, a scientific team at the Cagliari Astronomical Observatory is becoming acquainted with SETI search algorithms: both standard algorithms using the Fast Fourier Transform; and more versatile algorithms using the Kahrunen-Loève Transform (KLT) as well as Wavelets. The team is also investigating the possibility to pursue, with the SERENDIP VI setup, the simultaneous search for Extraterrestrial Intelligence, pulsars and Fast Radio Bursts.

Since 2013, several staff members of the Cagliari Astronomical Observatory have been involved with SETI activities, both from a technological and a scientific perspective. One major asset related to this research area is the presence, in the territory, of one of the most modern single-dish antennas: the Sardinia Radio Telescope (SRT). In this paper, we outline all aspects of our initiatives in the framework of the Search for ExtraTerrestrial Intelligence. We describe the development of SRT instrumentation for the purpose of receiving data that could potentially contain signs of life, as well as the directions that we are investigating for studying and analyzing these data, including in an international context.

Following to the Astronomical Validation report n°6 (AV-rep-006; Egron et al. 2015) dedicated to the C-band imaging performances of SRT through the observation of two Supernova Remnants (3C157 and W44), this second note is devoted to the calibration of the resulting maps.

This is a White Paper in support of the mission concept of the Large Observatory for X-ray Timing (LOFT), proposed as a medium-sized ESA mission. We discuss the potential of LOFT for the study of magnetospheres of isolated neutron stars. For a summary, we refer to the paper.

We report on observations of Supernova Remnants (SNR) with SRT in the frame of Astronomical Validation (AV) test activities. These tests are aimed to assess single-dish imaging performances of “SRT first light receivers” coupled with Total Power (TP) backend and related hw/sw subsystems/procedures (including innovative ad hoc imaging techniques based on OTF scans).

In the period 2012 June-2013 October, the Sardinia Radio Telescope (SRT) went through the technical commissioning phase. The characterization involved three first-light receivers, ranging in frequency between 300MHz and 26GHz, connected to a Total Power back-end. It also tested and employed the telescope active surface installed in the main reflector of the antenna. The instrument status and performance proved to be in good agreement with the expectations in terms of surface panels alignment (at present 300μmrms to be improved with microwave holography), gain (̃0.6K/Jy in the given frequency range), pointing accuracy (5 arcsec at 22GHz) and overall single-dish operational capabilities. Unresolved issues include the commissioning of the receiver centered at 350MHz, which was compromised by several radio frequency interferences, and a lower-than-expected aperture efficiency for the 22-GHz receiver when pointing at low elevations. Nevertheless, the SRT, at present completing its Astronomical Validation phase, is positively approaching its opening to the scientific community.

In the frame of AV tests “Single-­‐Dish Total Power Imaging of Bright Sources (I:s/w test)” (AV SNR1 test) we performed C band and K band (only central feed) imaging of point-­‐like bright calibration sources (i.e. 3C295 in particular).