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Ahmad Mehrabi

Ahmad Mehrabi

Academic rank: Associate Professor
ORCID:
Education: PhD.
ScopusId: 36705117200
HIndex:
Faculty: Faculty of Science
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Phone:

Research

Title
MAGNETIC ACTIVITY ANALYSIS FOR A SAMPLE OF G-TYPE MAIN SEQUENCE KEPLER TARGETS
Type
JournalPaper
Keywords
stars: activity – stars: magnetic field – stars: rotation – stars: solar-type
Year
2017
Journal Astrophysical Journal
DOI
Researchers Ahmad Mehrabi ، Han He ، Habib Khosroshahi

Abstract

The variation of a stellar light curve owing to rotational modulation by magnetic features (starspots and faculae) on the star’s surface can be used to investigate the magnetic properties of the host star. In this paper, we use the periodicity and magnitude of the light-curve variation as two proxies to study the stellar magnetic properties for a large sample of G-type main sequence Kepler targets, for which the rotation periods were recently determined. By analyzing the correlation between the two magnetic proxies, it is found that: (1) the two proxies are positively correlated for most of the stars in our sample, and the percentages of negative, zero, and positive correlations are 4.27%, 6.81%, and 88.91%, respectively; (2) negative correlation stars cannot have a large magnitude of light- curve variation; and (3) with the increase of rotation period, the relative number of positive correlation stars decreases and the negative correlation one increases. These results indicate that stars with shorter rotation period tend to have positive correlation between the two proxies, and a good portion of the positive correlation stars have a larger magnitude of light-curve variation (and hence more intense magnetic activities) than negative correlation stars.