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تسجيل مستخدم جديدGlobal asteroseismic properties of solar-like oscillations observed by Kepler : A comparison of complementary analysis methods
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We present the asteroseismic analysis of 1948 F-, G- and K-type main-sequence and subgiant stars observed by the NASA {em Kepler Mission}. We detect and characterise solar-like oscillations in 642 of these stars. This represents the largest cohort of main-sequence and subgiant solar-like oscillators observed to date. The photometric observations are analysed using the methods developed by nine independent research teams. The results are combined to validate the determined global asteroseismic parameters and calculate the relative precision by which the parameters can be obtained. We correlate the relative number of detected solar-like oscillators with stellar parameters from the {em Kepler Input Catalog} and find a deficiency for stars with effective temperatures in the range $5300 lesssim T_mathrm{eff} lesssim 5700$,K and a drop-off in detected oscillations in stars approaching the red edge of the classical instability strip. We compare the power-law relationships between the frequency of peak power, $ u_mathrm{max}$, the mean large frequency separation, $Delta u$, and the maximum mode amplitude, $A_mathrm{max}$, and show that there are significant method-dependent differences in the results obtained. This illustrates the need for multiple complementary analysis methods to be used to assess the robustness and reproducibility of results derived from global asteroseismic parameters.
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