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Solar activity emissions from submillimeter waves to infrared (SIRA)

Grant number: 06/06847-1
Support type:Research Projects - Thematic Grants
Duration: December 01, 2008 - June 30, 2014
Field of knowledge:Physical Sciences and Mathematics - Astronomy
Principal Investigator:Pierre Kaufmann
Grantee:Pierre Kaufmann
Home Institution: Centro de Rádioastronomia e Astrofísica Mackenzie (CRAAM). Universidade Presbiteriana Mackenzie (UPM). Instituto Presbiteriano Mackenzie. São Paulo , SP, Brazil
Associated grant(s):13/04248-7 - High-energy processes in solar flares: gamma-ray and sub-mm insights, AV.EXT
11/09700-0 - High-energy processes in the solar atmosphere and their diagnostics in the Earth's atmosphere, AV.EXT
09/15880-0 - Analysis and interpretation of high energy processes in solar flares, AV.EXT
09/00785-2 - Vatican Observatory Super Summer School 2009, AR.EXT
Associated scholarship(s):13/11125-9 - The study of sympathetic flares and their evidences at Sub-THz frequencies, BP.MS
12/11619-9 - Observational and calibration techniques upgrade for the Solar Submillimeter Telescope (SST), BP.DR
12/03007-3 - THz photometry of solar flare, BP.IC

Abstract

The Solar Submillimeter-wave Telescope (SST) results obtained at central frequencies close to 200 and 400 GHz added to the first mid-infrared high cadence observations at El Leoncito, Argentina Andes, has produced new and unique evidences on solar activity. They have raised new fundamental interpretation questions. It has been possible to characterize well known thermal mechanisms at quiescent and active or bursting sources, as well as non-thermal emission spectra with maximum emission at microwaves. It has been found burst emissions previously unsuspected to exist, implying in highly energetic particle acceleration. It has been dramatically demonstrated that the decades-long assumption that only emissions from thermal processes dominate the submillimeter-waves to infra-red range was wrong. The principal achievements we emphasize (a) the submillimeter-wave pulsations (fractions of a second to seconds), appearing superimposed on bursts, with or without the presence of an evident impulsive bulk component, exhibiting the pulse rate with time varying in correspondence to time profiles at high energies (hard X- and g-rays), (b) pulsations in active regions, sometimes unrelated to other evident burst or flare, associated to coronal mass ejections (CMEs), (c) a new impulsive burst spectral component with flux increasing with frequency, peaking in the THz range, appearing along with but distinct from the well-known single spectral maximum at microwaves; (d) peculiar spectral features of quiescent and flaring active regions. The first high cadence observations in the mid-infrared, centered at 10 mm (30 THz), in addition to identify emissions from thermal processes in active regions, have shown for the first time the presence of numerous rapid brightening (seconds of time) during bursts. Further progress irequires dedicated SST operations in campaigns coordinated with mid-IR high cadence observations. They must be complemented by simultaneous patrol observations at millimeter wavelengths, 45 and 90 GHz, presently inexistent. The proposed unique ground-based observations will become of crucial importance to complement terahertz solar photometry considered by a new space mission. (AU)

Articles published in Agência FAPESP about the research grant
Technology developed in Brazil will be part of the International Space Station  
Brazilian astronomers observe solar flares at unprecedented frequencies 
NASA launches Brazilian solar observation telescope 
Scientists discover intense infrared shine in solar explosion  
Brazilian experiment will investigate mysterious solar radiation 

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)
KUDAKA, A. S.; CASSIANO, M. M.; MARCON, R.; CABEZAS, D. P.; FERNANDES, L. O. T.; HIDALGO RAMIREZ, R. F.; KAUFMANN, P.; DE SOUZA, R. V. The New 30 THz Solar Telescope in So Paulo, Brazil. SOLAR PHYSICS, v. 290, n. 8, p. 2373-2379, AUG 2015. Web of Science Citations: 1.
KLOPF, J. MICHAEL; KAUFMANN, PIERRE; RAULIN, JEAN-PIERRE; SZPIGEL, SERGIO. THE CONTRIBUTION OF MICROBUNCHING INSTABILITY TO SOLAR FLARE EMISSION IN THE GHz TO THz RANGE OF FREQUENCIES. ASTROPHYSICAL JOURNAL, v. 791, n. 1 AUG 10 2014. Web of Science Citations: 8.
ZAITSEV, V. V.; STEPANOV, A. V.; KAUFMANN, P. On the Origin of Pulsations of Sub-THz Emission from Solar Flares. SOLAR PHYSICS, v. 289, n. 8, p. 3017-3032, AUG 2014. Web of Science Citations: 10.

Please report errors in scientific publications list by writing to: cdi@fapesp.br.