Investigating Solar Acoustic Oscillations and Surface Activity During the Current Minimum

The Solar Cycle, a cyclic change with a period of about 11 years, is the waxing and waning of the Solar Magnetic field with time. Other indicators of solar activity follow a similar trend, as inferred from direct measurements above the solar surface. However, measuring the magnetic field beneath the surface cannot be accomplished through direct methods. Past helioseismic studies have revealed a strong correlation between the variations in solar acoustic oscillation frequencies of the waves propagating below the Sun’s surface and magnetic activity indicators above the surface, allowing the frequencies to serve as an activity proxy for the interior. During the activity minimum between cycles 23 and 24, several studies identified different minimum periods in the layers below and above the surface raising questions on the origin of the solar cycles. In this paper, we evaluate the current minimum and present results on the identified epochs of minimum. This allows us to investigate the connection between various layers of solar interior and the atmosphere. The oscillation frequencies that we use for this study are derived from the Global Oscillation Network Group (GONG) observations while several indicators of the solar activity are used for above surface conditions. This work is carried out through the National Solar Observatory Research Experiences for Undergraduates (REU) Program, which is funded by the National Science Foundation (NSF) through Award No. 1659878.