Solar patrol polarization telescopes at 45 and 90 GHz

• Grant number: 09/50637-0
• Support Opportunities: Regular Research Grants
• Duration: April 01, 2010 - October 31, 2013
• Field of knowledge: Physical Sciences and Mathematics - Astronomy - Astronomical Instrumentation
• Principal Investigator: Adriana Benetti Marques Valio
• Grantee: Adriana Benetti Marques Valio
• Host Institution: Escola de Engenharia (EE). Universidade Presbiteriana Mackenzie (UPM). Instituto Presbiteriano Mackenzie. São Paulo , SP, Brazil

Abstract

The spectra of solar flares provide important information about the physics involved in the flaring process. Presently, however, there is a large frequency gap at radio frequencies between 20 and 200 GHz. Unfortunately, this gap hinders the determination of important flare parameters such as: (i) the frequency of the peak of the spectra, or turnover frequency, which yields the magnetic field intensity in the flaring source and electron density; (ii) the optically thin frequency slope, that is related to the accelerated electrons with a power-law energy distribution, allowing information about the acceleration mechanism; (iii) and other physical parameters such as source size and inhomogeneities that may also be estimated from a spectra with complete spectral coverage. Recently a new spectral component at high frequencies was discovered with fluxes increasing above 200 GHz, distinct from the traditional microwave component, with peak frequencies at about 10 GHz. To elucidate the nature of both components and fully characterize the spectra of solar flares in order to derive their main physical parameters, described above, we plan to obtain continuous observations at the intermediate frequencies of 45 and 90 GHz. This will be achieved by installing two antennas with receivers at 45 and 90 GHz, capable of measuring circular polarization, at CASLEO Observatory, the same site of the Solar Submillimetric Telescope (SST). CASLEO has already proven to be a good site for submillimetric observations and must become highly transparent for observations at 45 and 90 GHz for 90% of the time. The new telescopes will operate daily, simultaneously with SST at 212 and 405 GHz. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

DA SILVA, DOUGLAS FELIX; VALIO, ADRIANA. Broken Power-law Energy Spectra of the Accelerated Electrons Detected in Radio and Hard X-Rays during the SOL2013-05-13 Event. Astrophysical Journal Letters, v. 915, n. 1, JUL 2021. (09/50637-0, 13/10559-5, 13/24155-3)