98 citations · 1.2k across the 60 of their papers we have counts for
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Solar twins in M67 : Evolutionary status and lithium abundance
M. Castro, J. D. do Nascimento, K. Biazzo +2
We determine the age and mass of the three best solar twin candidates in open cluster M67 through lithium evolutionary models. We computed a grid of evolutionary models with non-st…
Wavelet analysis of stellar rotation and other periodicities
D. B. de Freitas, I. de C. Leão, B. L. Canto Martins +1
The wavelet transform has been used for numerous studies in astrophysics, including signal--noise periodicity and decomposition as well as the signature of differential rotation in…
Nonextensivity in the solar magnetic activity during the increasing phase of solar Cycle 23
D. B. de Freitas, J. R. De Medeiros
In this paper we analyze the behavior of the daily Sunspot Number from the Sunspot Index Data Center (SIDC), the mean Magnetic Field strength from the National Solar Observatory/Ki…
An Overview of the Rotational Behavior of Metal--Poor Stars
C. Cortés, J. R. P. Silva, A. Recio-Blanco +3
The present paper describes the behavior of the rotational velocity in metal--poor stars ([Fe/H]<-0.5 dex) in different evolutionary stages, based on Vsini values from the literatu…
On the rotational behavior of parent stars of extrasolar planets
S. Alves, J. D. do Nascimento, J. R. De Medeiros
We analyzed the behavior of the rotational velocity in the parent stars of extrasolar planets. Projected rotational velocity v sin i and angular momentum were combined with stellar…
On the rotational behavior of parent stars of extrasolar planets
Sanzia Alves, Jose Dias do Nascimento, Jose Renan de Medeiros
We analyzed the behavior of the rotational velocity in the parent stars of extrasolar planets. Projected rotational velocity v sin i and angular momentum were combined with stellar…
Rotation and lithium abundance of solar-analog stars. Theoretical analysis of observations
J. D. do Nascimento, J. S. da Costa, J. R. De Medeiros
Rotational velocity, lithium abundance, and the mass depth of the outer convective zone are key parameters in the study of the processes at work in the stellar interior, in particu…
Evolution of the solar activity over time and effects on planetary atmospheres. II. kappa^1 Ceti, an analog of the Sun when life arose on Earth
I. Ribas, G. F. Porto de Mello, L. D. Ferreira +6
The early evolution of Earth's atmosphere and the origin of life took place at a time when physical conditions at the Earth where radically different from its present state. The ra…