Artículos de revistas
POlarization Emission of Millimeter Activity at the Sun (POEMAS): New Circular Polarization Solar Telescopes at Two Millimeter Wavelength Ranges
Registro en:
Solar Physics. Springer, v. 283, n. 2, n. 651, n. 665, 2013.
0038-0938
WOS:000316265100026
10.1007/s11207-013-0237-4
Autor
Valio, A
Kaufmann, P
de Castro, CGG
Raulin, JP
Fernandes, LOT
Marun, A
Institución
Resumen
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) We present a new system of two circular polarization solar radio telescopes, POEMAS, for observations of the Sun at 45 and 90 GHz. The novel characteristic of these instruments is the capability to measure circular right- and left-hand polarizations at these high frequencies. The two frequencies were chosen so as to bridge the gap at radio frequencies between 20 and 200 GHz of solar flare spectra. The telescopes, installed at CASLEO Observatory (Argentina), observe the full disk of the Sun with a half power beam width of 1.4(a similar to), a time resolution of 10 ms at both frequencies, a sensitivity of 2 -aEuro parts per thousand 4 K that corresponds to 4 and 20 solar flux unit (=10(4) Jy), considering aperture efficiencies of 50 +/- 5 % and 75 +/- 8 % at 45 and 90 GHz, respectively. The telescope system saw first light in November 2011 and is satisfactorily operating daily since then. A few flares were observed and are presented here. The millimeter spectra of some flares are seen to rise toward higher frequencies, indicating the presence of a new spectral component distinct from the microwave one. 283 2 651 665 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Mackpesquisa Argentine agency CONICET American US AFOSR Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)