TY  - JOUR
T1  - Variations in Diffusion Coefficients on Equinox Days at Specified Critical Heights of the Ionosphere at the Equator
TT  - Ekvatorda Iyonosferin Bazı Kritik Yüksekliklerinde  Difüzyon Katsayılarının Ekinoks Günlerinde Değişimi
AU  - Kurt, Kadri
AU  - Yeşil, Ali
PY  - 2024
DA  - September
Y2  - 2024
DO  - 10.55525/tjst.1459356
JF  - Turkish Journal of Science and Technology
JO  - TJST
PB  - Fırat University
WT  - DergiPark
SN  - 1308-9080
SP  - 407
EP  - 414
VL  - 19
IS  - 2
LA  - en
AB  - This study investigates the local time diffusion coefficient for stable and unstable ( , ) states at the equator (00), "the geographical latitude where the first peak of the magnetic equatorial trough in the ionosphere occurs," during the spring and fall equinoxes (March 21 and September 23). The findings show that the diffusion tensor in a steady state is completely real and has a magnitude equal to the speed of light in a steady state. But in the unsteady state, the diffusion tensor consists of two parts, real and imaginary. The diagonal elements of the real part tensor are of the size of the conductivity in the ionosphere and the elements of the imaginary part are of the size of the speed of sound with about the same magnitude.  Furthermore, for all assumed conditions, the diffusion elements form the first peak of the magnetic equatorial trough at 6.00 am local time.
KW  - Diffusion Tensor
KW  - Ionospheric Plasma
KW  - Diffusion Coefficient
N2  - Bu çalışmada, ilkbahar ve sonbahar ekinoksları (21 Mart ve 23 Eylül) sırasında “iyonosferdeki manyetik ekvatoral çukurun ilk zirvesinin meydana geldiği coğrafi enlem” olan ekvatorda (00) kararlı ve kararsız ( , ) durumlar için yerel zaman zaman difüzyon katsayısı araştırılmıştır. Bulgulara göre, kararlı durumda difüzyon tensörünün tamamen gerçek olduğunu ve sabit bir durumda ışık hızına eşit bir büyüklüğe sahip olduğunu göstermektedir. Fakat kararsız durumda difüzyon tensörü; reel ve sanal olmak üzere iki kısımdan oluşmaktadır. Reel kısım tensörününün köşegen elemanları iyonosferdeki büyüklüğü iletkenlik boyutunda, sanal kısmının elamanları yaklaşık aynı büyüklükte ses hızı boyutundadır. Bunun yanı sıra bütün kabul edilen şartlarda difüzyon elemanları sabah 6.00’da yerel zamanda manyetik ekvator çukurun ilk tepesini oluşturmaktadır.
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UR  - https://doi.org/10.55525/tjst.1459356
L1  - https://dergipark.org.tr/en/download/article-file/3824015
ER  -