Abstract Details
| Name: Javaraiah Javaraiah Affiliation: Formerly Indian Institute of Astrophysics Conference ID: ASI2019_213 Title : Variations in north-south asymmetry of solar maximum and minimum Authors and Co-Authors : J. Javaraiah Abstract Type : Poster Abstract Category : Sun and the Solar System Abstract : Study of north-south asymmetry in solar activity is important for better understanding solar dynamo processes and solar variability. We analyzed the sunspot group daily data of Greenwich Photoheliographic Results (GPR) during the period 1874-1976 and Debrecen Photoheligraphic Data (DPD) during the period 1977-2015 and studied north-south asymmetry in the maxima and the minima of the solar cycles 12-24. We derived the time-series of the 13-month smoothed monthly mean corrected whole-spot areas of the sunspot groups in the Sun's whole sphere (WSGA), northern hemisphere (NSGA), and southern hemisphere (SSGA). From these smoothed time series we obtained the values of the maxima and minima, and the corresponding epochs, of the WSGA, NSGA, and SSGA cycles 12-24. We find that variation in the north-south asymmetry of the solar minimum is more pronounced than that of the maximum. There exist 130-140-year and 44-66-year periodicities in the north-south asymmetry of maximum and minimum, respectively. The ratio of the large to the small numbers of sunspot groups is generally smaller in the minimum than that in the maximum of a solar cycle. That is, the epochs of the minima and maxima of solar cycles comprise relatively small and large numbers of large sunspot groups, respectively. The magnetic structures of large and small sunspot groups may be rooted at relatively deep and sallow layers of the solar convection zone. Hence, the long-term periodicities of north-south asymmetry in the solar maximum and minimum might originate at relatively deep and sallow layers of the solar convection zone, respectively. Therefore, there exits a difference in the long-term variations of solar maximum and minimum and in the corresponding north-south asymmetry. |