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تسجيل مستخدم جديدDetection of l=4 and l=5 modes in 12 years of solar VIRGO-SPM data --- Tests on Kepler observations of 16 Cyg A and B
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We present the detection of l=4 and l=5 modes in power spectra of the Sun, constructed from 12 yr full-disk VIRGO-SPM data sets. A method for enhancing the detectability of these modes in asteroseismic targets is presented and applied to Kepler data of the two solar analogues 16 Cyg A and B. For these targets we see indications of a signal from l=4 modes, while nothing is yet seen for l=5 modes. We further simulate the power spectra of these stars and from this we estimate that it should indeed be possible to see such indications of l=4 modes at the present length of the data sets. In the simulation process we briefly look into the apparent misfit between observed and calculated mode visibilities. We predict that firm detections of at least l=4 should be possible in any case at the end of the Kepler mission. For l=5 we do not predict any firm detections from Kepler data.
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