Inaugurata la più grande antenna radioastronomica italiana

Con una cerimonia estremamente suggestiva è stato di recente inaugurato il Sardinia Radio Telescope. Oltre a numerose autorità nazionali e locali ed un’ampia rappresentanza di scienziati provenienti dai principali centri internazionali di radioastronomia, alla cerimonia hanno partecipato circa 2000 cittadini giunti dai comuni limitrofi interessati a conoscere questo nuovo “vicino di casa”. Risalta infatti in un passaggio naturalisticamente incontaminato, quale è il sito di Pranu Sanguni, questo nuovo impianto dalle dimensioni imponenti e costruito con tecnologia avanzatissima tale da renderlo uno dei più evoluti e potenti strumenti del mondo per lo studio delle emissioni radio provenienti dai corpi celesti e per applicazioni di geodinamica e di scienze spaziali.The Sardinia Radio Telescope was recently inaugurated in the course of an impressive ceremony. In addition to the representatives of local and national authorities, and scientists from leading centres of radio astronomy all over the world, the ceremony was also attended by around 2,000 local people from the nearby areas who were curious to meet this ‘new neighbour’ of theirs. This new installation of spectacular dimensions does indeed stand out in the unspoilt natural landscape of the site of Pranu Sanguni. Built with groundbreaking technology, it is in fact one of the most evolved and powerful instruments in the world for the study of radio emissions originating from celestial bodies and for geodynamics and space science applications

Characterization of the SKA1-Low prototype station Aperture Array Verification System 2

The low frequency component of the Square Kilometre Array (SKA1-Low) will be an aperture phased array located at the Murchison Radio-astronomy Observatory (MRO) site in Western Australia. It will be composed of 512 stations, each consisting of 256 log-periodic dual-polarized antennas, and will operate in the low frequency range (50 to 350 MHz) of the SKA bandwidth. The Aperture Array Verification System 2 (AAVS2), operational since late 2019, is the last full-size engineering prototype station deployed at the MRO site before the start of the SKA1-Low construction phase. The aim of this paper is to characterize the station performance through commissioning observations at six different frequencies (55, 70, 110, 160, 230, and 320 MHz) collected during its first year of activities. We describe the calibration procedure, present the resulting all-sky images and their analysis, and discuss the station calibratability and system stability. Using the difference imaging method, we also derive estimates of the SKA1-Low sensitivity for the same frequencies and compare them with those obtained through electromagnetic simulations across the entire telescope bandwidth, finding good agreement (within 13%). Moreover, our estimates exceed the SKA1-Low requirements at all considered frequencies by up to a factor of ∼2.3. Our results are very promising and allow for an initial validation of the AAVS2 prototype station performance, which is an important step toward the coming SKA1-Low telescope construction and science