Diurnal variation of B parameters over Havana at low solar activity

We present a preliminary table of mean values of the F2 region bottomside parameters B0 (thickness parameter) and B1 (shape parameter) for the time interval 00.00 LT-23.00 LT. Data from vertical ionospheric soundings at Havana (23°N; 278°E; Dip 54.6°N; Modip 44.8°N) during wintertime and low solar activity (R12≈15) were used in the study. The diurnal variation of B0 shows higher values during nighttime than during daytime. The B1 parameter tends to be lower during nighttime than during daytime.