Rapid pulsations in sub-THz solar bursts

A new solar burst emission spectral component has been found showing sub-THz fluxes increasing with frequency, spectrally separated from the well known microwave component. Rapid pulsations are found present in all events observed at the two frequencies of the solar submillimeter-wave telescope (SST): 212 and 405 GHz. They were studied in greater detail for three solar bursts exhibiting the new THz spectral component. The pulse amplitudes are of about 5-8% of the mean flux throughout the bursts durations, being comparable for both frequencies. Pulsations range from one pulse every few seconds to 8-10 per second. The pulse repetition rates (R) are linearly proportional to the mean burst fluxes (S), following the simple relationship S = k R, suggesting that the pulsations might be the response to discrete flare particle accelerator injections quantized in energy. Although this result is consistent with qualitative trends previously found in the GHz range, the pulse amplitude relative to the mean fluxes at the sub-THz frequencies appear to be nearly ten times smaller than expected from the extrapolation of the trends found in the GHz range. However there are difficulties to reconcile the nearly simultaneous GHz and THz burst emission spectrally separated components, exhibiting rapid pulsations with considerably larger relative intensities in the GHz range.Comment: 9 pages and 11 figures, submitted to Astrophys. J; Revised version accepted by ApJ on 4 March 200

V olimpíada brasileira de astronomia

Neste trabalho, apresentamos os resultados da V Olimpíada Brasileira de Astronomia, que ocorreu em 11/05/2002 em todos os estabelecimentos de ensino fundamental e médio, previamente cadastrados. Participaram do evento 60.338 alunos, distribuídos por 1469 escolas pertencentes a todos os Estados brasileiros. Uma equipe de 5 alunos foi escolhida para representar o Brasil na VII Olimpíada Internacional de Astronomia, que ocorreu na Rússia, em 2002, e dois de nossos alunos ganharam a medalha de bronze.In this work we show the results of the V Brazilian Olympiad of Astronomy, which took place on 11/05/2002 in all primary or secondary schools that previously registered. 60338 students distributed over 1.469 schools from all Brazilian States took part in this event. A team of 5 students was selected to represent Brazil at the VII International Olympiad of Astronomy that occurred in Russia in 2002. Two of our students were awarded the bronze medal in that event

V olimpíada brasileira de astronomia

Neste trabalho, apresentamos os resultados da V Olimpíada Brasileira de Astronomia, que ocorreu em 11/05/2002 em todos os estabelecimentos de ensino fundamental e médio, previamente cadastrados. Participaram do evento 60.338 alunos, distribuídos por 1469 escolas pertencentes a todos os Estados brasileiros. Uma equipe de 5 alunos foi escolhida para representar o Brasil na VII Olimpíada Internacional de Astronomia, que ocorreu na Rússia, em 2002, e dois de nossos alunos ganharam a medalha de bronze.In this work we show the results of the V Brazilian Olympiad of Astronomy, which took place on 11/05/2002 in all primary or secondary schools that previously registered. 60338 students distributed over 1.469 schools from all Brazilian States took part in this event. A team of 5 students was selected to represent Brazil at the VII International Olympiad of Astronomy that occurred in Russia in 2002. Two of our students were awarded the bronze medal in that event