MHD Seismology of a Coronal Loop System by the First Two Modes of Standing Kink Waves

摘要: We report the observation of first two harmonics horizontally polarized kink waves excited in a coronal loop system lying at south-east AR 11719 on 2013 April 11. The detected periods fundamental mode ($P_1$), its overtone ($P_2$) northern half, and that southern one are $530.2 \pm 13.3$, $300.4 27.7$, $334.7 22.1$ s, respectively. halves same considering uncertainties measurement. estimate average electron density, temperature, length as $(5.1 0.8) \times 10^8$ cm$^{-3}$, $0.65 0.06$ MK, $203.8 13.8$ Mm, As zeroth order estimation, magnetic field strength, $B = 8.2 1.0$ G, derived by seismology using matches with potential model. extrapolation model also shows asymmetric nonuniform distribution along loop. Using amplitude profile distributions both overtone, we observe antinode positions shift towards weak region results indicate density stratification temperature difference effects larger than variation effect period ratio. On other hand, has greater eigenfunction does for this case.