Sardinia Radio Telescope: General Description, Technical Commissioning and First Light

TL;DR

The Sardinia Radio Telescope's commissioning phase demonstrated promising performance metrics across multiple receivers and systems, confirming its readiness for scientific use despite some unresolved technical issues.

Contribution

This paper provides the first comprehensive technical commissioning and performance characterization of the Sardinia Radio Telescope, including initial results from multiple receivers and active surface testing.

Findings

Surface panels aligned within 300 um rms

Gain approximately 0.6 K/Jy across 300MHz-26GHz

Pointing accuracy of 5 arcsec at 22 GHz

Abstract

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 300 um rms to be improved with microwave holography), gain (~0.6 K/Jy in the given frequency range), pointing accuracy (5 arcsec at 22 GHz) and overall single-dish operational capabilities. Unresolved issues include the commissioning of the receiver centered at 350 MHz, 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.