λ17.1 nm Fe IX Line in the radiation spectrum of slow magneto-acoustic waves propagating in the solar crown
Heading:
| 1Mamedov, SG, Aliyeva, ZF, Alisheva, KI 1Nasir al-Din al-Tusi Shamakhi Astrophysical Observatory, Pirqulu, Azerbaijan |
| Kinemat. fiz. nebesnyh tel (Online) 2021, 37(6):49-61 |
| https://doi.org/10.15407/kfnt2021.06.049 |
| Start Page: Solar Physics |
| Language: Ukrainian |
Abstract: The profiles of the X 17.1 nm Fe IX line in the emission spectrum of slow magneto-acoustic waves propagating in coronal loops are calculated for cases of an optically thin layer and constant density. The line profiles were calculated for the following parameter values: the amplitude of the velocity at the wave υ0 = 10 km/s, the width of the coronal loop is 2000 km and 5000 km, the wavelength Λ = 20000 km and 50000 km, the value of the Doppler width Δλd = 1 pm, and at values of the angle of view and at different phases of the wave. The true value of the energy flux density is 622 erg⋅cm-2s-1. The calculated values of the energy flux density strongly depend on the angle of view and on the wave phase and range from zero at large values of theta to 2x 103 erg⋅cm-2s-1, the values of the Doppler velocities υd and the veiocities of non-thermal motions υnt at small values of Θ have a maximum value of ~12 km/s and decrease almost to zero at large values of Θ. At small values of the angle of the line of sight (Θ 30°, the asymmetry is almost invisible. |
| Keywords: MHD waves, slow magneto-acoustic waves, solar corona |
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