AUTHOR=Chakraborty Sayak , Paul Rakhi , Basak Tamal 

TITLE=On the altitude profile of lower ionospheric D-region response time delay during solar flares

JOURNAL=Frontiers in Environmental Science

VOLUME=Volume 10 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2022.1020137

DOI=10.3389/fenvs.2022.1020137

ISSN=2296-665X

ABSTRACT=The D-region ionosphere is sluggish in nature while responding to the incoming solar radiation. We study the altitude ($h$) profile of mid-latitude D-region response time delay ($\Delta t$) during three chosen solar flares, namely, C5.2, M5.2 and X2.2 classes. We solve `electron continuity equation' numerically at each and every $h$ to obtain $\Delta t$-$h$ profile. We investigate the (i) latitudinal variation (over both northern and southern hemispheres) \& (ii) seasonal variation (throughout the year) of $\Delta t$-$h$ profiles of each of these solar flares separately. We go over noteworthy variations of $\Delta t$-$h$ profile for both (i) \& (ii) with reasonably different results over different hemispheres. Also, we study some contrasting behaviours of $\Delta t$-$h$ profile of X2.2 class for both (i) \& (ii) in comparison to C5.2 or M5.2 classes. We conclude the outcome with possible explanations.