Title of article :
Phase-induced amplitude apodization of telescope pupils for extrasolar terrestrial planet imaging
Author/Authors :
Guyon، O. نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2003
Pages :
-378
From page :
379
To page :
0
Abstract :
V390 Aurigae (HD 33798) is a rapidly rotating, lithium rich, late-type giant whose distinctive characteristics include a high X-ray luminosity observed by the XMM-newton space observatory. Series of lines of highly ionized Fe and several Lyman lines of hydrogen-like ions and triplet lines of helium-like ions are visible in the reflection grating spectra, most notably from O and Ne. X-ray emission from plasma at high temperature ( T> 107 K) indicates intense flaring activity on this star. Analysis results suggest a scenario where the corona of V390 Aurigae is dominated by large magnetic structures similar in size to interconnecting loops between solar active regions but significantly hotter. The interaction of these structures could explain the permanent flaring activity on large scales that is responsible for heating plasma to high temperatures. The intense activity on V390 Aurigae is related to its evolutionary position at the bottom of the red giant branch. It is anticipated that the rotation of the star will spindown in the future, thus decreasing the efficiency of its (alpha-omega)dynamo with the suppressing of large scale magnetic structures in its corona.
Keywords :
techniques , high angular resolution , stars , planetary systems , telescopes
Journal title :
Astronomy and Astrophysics
Serial Year :
2003
Journal title :
Astronomy and Astrophysics
Record number :
77759
Link To Document :
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