The solar ionization rate of the interplanetary hydrogen as a function of a heliomagnetic latitude: A new model for the interplanetary Lyman alpha studies

In this work we have modelled the solar wind proton flux which varies as a function of distance to the heliomagnetic equator and its effects on the in terplanetary Lyman alpha radiation. The results imply that a groove observe d in Lyman alpha intensity patterns toward the upwind direction Bertaux et al. disappears when the tilt angle of the heliomagnetic equator is larger t han 20 degrees. The observations by Bertaux et al. were measured during the solar wind minimum when the tilt angle of the streamer belt is low. During the solar wind maximum when the tilt angle of the streamer belt is large t he Lyman alpha groove should disappear according to our results.