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Asteroseismology of solar-type stars with K2

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 نشر من قبل William Chaplin
 تاريخ النشر 2015
  مجال البحث فيزياء
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We present the first detections by the NASA K2 Mission of oscillations in solar-type stars, using short-cadence data collected during K2 Campaign,1 (C1). We understand the asteroseismic detection thresholds for C1-like levels of photometric performance, and we can detect oscillations in subgiants having dominant oscillation frequencies around $1000,rm mu Hz$. Changes to the operation of the fine-guidance sensors are expected to give significant improvements in the high-frequency performance from C3 onwards. A reduction in the excess high-frequency noise by a factor of two-and-a-half in amplitude would bring main-sequence stars with dominant oscillation frequencies as high as ${simeq 2500},rm mu Hz$ into play as potential asteroseismic targets for K2.



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