A study of 732.0 nm dayglow emission at the equator under varying atomic oxygen density conditions for equinox and solstice cases

Abstract

AbstractA comprehensive model is developed to compute the volume emission rate of O+(2P) 732.0 nm dayglow emission. The modeled volume emission rates are compared with the measurements as provided by Atmosphere Explorer C satellite and Dynamics Explorer 2 spacecraft. It is found that the model explains quite well the measured emission profiles. The present model is used to study the effect of atomic oxygen abundance on the volume emission rate of 732.0 nm dayglow emission at the equator for equinox and solstice. To study the effect of atomic oxygen abundance on 732.0 nm dayglow emission, the atomic oxygen number densities obtained from the NRLMSISE‐00 model are increased (or decreased) in an increment (or decrement) of 20% and are incorporated into the model to compute volume emission rate profiles. The present study shows that the peak emission rate (PER) varies linearly below the reference level of atomic oxygen number density and does not vary linearly above the reference level of atomic oxygen number density. The atomic oxygen number density at reference level corresponds to that value which is obtained from the NRLMSISE‐00 model. It is found that the altitude of peak emission rate moves upward as the F10.7 solar index increases. On average the upward movement of altitude of PER is about 9 km for both the equinox and solstice cases. The upward movement of the altitude of peak emission rate is due to the enhancement in atomic oxygen number density with increase in F10.7 solar index.