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Interação estrela planeta: sobre o magnetismo de planetas gigantes gasosos
(Universidade Federal do Rio Grande do NorteBRUFRNPrograma de Pós-Graduação em FísicaFísica da Matéria Condensada; Astrofísica e Cosmologia; Física da Ionosfera, 2012-02-16)
In this thesis we analyze the effects that the presence of a near gas giant planet can
cause in its host star. It has been argued that the star planet interaction can cause
changes in the coronal and chromospheric stellar ...
Two step mechanism for Moreton wave excitations in a blast-wave scenario: The 2006 December 06 case study
(Wiley Blackwell Publishing, Inc, 2015-10)
We examine the capability of a blast-wave scenario - associated with a coronal flare or to the expansion of CME flanks - to reproduce a chromospheric Moreton phenomenon. We also simulate the Moreton event of 2006 December ...
ζ1 + ζ2 Reticuli binary system: a puzzling chromospheric activity pattern
(Wiley Blackwell Publishing, Inc, 2018-05)
We perform, for the first time, a detailed long-term activity study of the binary system ζ Ret. We use all available HARPS spectra obtained between the years 2003 and 2016. We build a time series of the Mount Wilson S index ...
The fast and slow H alpha chromospheric responses to non-thermal particles produced during the 1991 March 13 hard X-ray/gamma-ray flare at similar to 08 UTC
(Edp Sciences S ALes Ulis Cedex AFrança, 2000)
Chemical composition of a sample of bright solar-metallicity stars
(WILEY-V C H VERLAG GMBH, 2015)
We present a detailed analysis of seven young stars observed with the spectrograph SOPHIE at the Observatoire de Haute-Provence for which the chemical composition was incomplete or absent in the literature. For five stars, ...
The Na i D resonance lines in main-sequence late-type stars
(Oxford University Press, 2007-07)
We study the sodium D lines (D1: 5895.92 Å; D2: 5889.95 Å) in late-type dwarf stars. The stars have spectral types between F6 and M5.5 (B - V between 0.457 and 1.807) and metallicity between and 0.6. We obtained medium-resolution ...
SALT observations of the chromospheric activity of transiting planet hosts: Mass-loss and star-planet interactions
(Oxford University, 2017)
We measured the chromospheric activity of the four hot Jupiter hosts WASP-43, WASP-51/HAT-P-30, WASP-72 and WASP-103 to search for anomalous values caused by the close-in companions. The Mount Wilson CaIIH&KS-index was ...
The effect of ISM absorption on stellar activity measurements and its relevance for exoplanet studies
(EDP Sciences, 2017-05)
Past ultraviolet and optical observations of stars hosting close-in Jupiter-mass planets have shown that some of these stars present an anomalously low chromospheric activity, significantly below the basal level. For the ...
The role of magnetic bald patches in surges and arch filament systems
(EDP Sciences, 2002-08)
The short-lived active region (AR) NOAA 7968 was thoroughly observed all along its disk transit (June 3 to 10, 1996) from space and from the ground. During the early stage of its evolution, flux emerged in between the two ...