Available telescopes

This page describes the solar instruments available in MackSun, including POEMAS and SST, their observing frequencies, temporal resolution and observational context.

POEMAS

The POlarization Emission of Millimeter Activity at the Sun (POEMAS) consists of two solar radiotelescopes operating at 45 GHz and 90 GHz, with independent detection of right and left circular polarization. In operation since 2013 at the CASLEO observatory in Argentina, POEMAS provides continuous monitoring of the Sun in the millimeter range.

The system achieves a temporal resolution of 10 ms, which makes it suitable for detecting fast solar phenomena such as bursts during flares. Calibration is performed through Dicke switching and noise diodes, ensuring stability better than 0.05 K. Each antenna has a beam with HPBW ≈ 6°, with sidelobe levels below -30 dBc, ensuring reliable flux density measurements.

POEMAS data provide unique insights into the dynamics of solar flares at millimeter wavelengths, complementing observations at radio and submillimeter frequencies.

Location: CASLEO - Complejo Astronómico El Leoncito, San Juan, Argentina. Google Maps

POEMAS Telescope

SST

The Solar Submillimeter Telescope (SST) has been operating at CASLEO since 1999 and was the first telescope to continuously monitor the Sun in the submillimeter domain. It observes at 212 GHz (1.4 mm) and 405 GHz (0.7 mm) using six radiometers (four at 212 GHz and two at 405 GHz), allowing simultaneous multi-channel detection.

The instrument records data at different cadences:
● fast: 5 ms, suited for rapid transient detection;
● intg: 40 ms, for intermediate studies;
● instr: 1 s, for long-term monitoring with calibration and auxiliary parameters.

SST employs a dual-beam system with a 1.5 m diameter antenna, achieving Its pointing system achieves millidegree precision, supporting solar tracking, RA-Dec mapping, radial scans, and tipping scans for atmospheric opacity determination. Typical zenith opacities at CASLEO are τ(212 GHz) ≈ 0.26 and τ(405 GHz) ≈ 1.9, highlighting the challenges and uniqueness of submillimeter observations.

SST data are fundamental for investigating particle acceleration and high-frequency components of solar flares, providing complementary information to millimeter and radio domains.

Location: CASLEO - Complejo Astronómico El Leoncito, San Juan, Argentina. Google Maps: Google Maps

SST Telescope