Analysis of the solar observations of year 2001 made in Antalya by means of the astrolabe of TUBITAK national observatory

There have existed the short and long-term variations that can be related with the sunspot cycle, the solar rotation and the solar flares. However, the phases and amplitudes between the variation of solar radius and those quantities have still continued to be debated. In this work, the observations made at the zenith distances 300, 450 and 600 by the solar astrolabe with CCD of the TUBITAK National Observatory (TUG) were analysed. The average value of radius computed over the 556 measurements obtained between February and November in year 2001 was found to be 959.26 ± 0.01 with a standard deviation of 0.32. In addition, the temporal variations of solar radius were investigated and the several periods varying between 11.5 and 66.7 days that can be related with the solar rotation, the sunspot lifetime, and solar flares were obtained