The Sun's magnetic field characterized by the evolution of its minimum magnetic flux with effects from the core

Based on the successful reconstruction of the global solar magnetic field by a number of investigators it seems clear that the field strength (used here as B(nT)) has increased significantly during the last ∼300 years. However, it has been demonstrated that a weak field strength has unexpected consequences for the near Earth environment relative to the high probability of the detection of large fluence proton events. For this reason emphasis has been placed on evaluating the minimum values (Bmin) of the total magnetic flux, which upon visual examination seems to resemble variations between sequential states of equilibrium of the quiet Sun termed group one to six, which extend over several Schwabe cycles. Whereas in general the magnetic field strength B(nT) increases with decreasing cycle length, an inverse relationship can be demonstrated for the field strength with decreasing cycle length if the magnetic flux Bmax is expressed as a fraction of Bmin and can be used as a diagnostic tool. In fact, two separate trends can be identified: (1) a two-step function between two consecutive groups, and (2) three non-consecutive groups showing the common characteristic of following the termination of an extended period of low solar activity. Furthermore, it can be shown that the approach of Bmax and Bmin to each other in their temporal evolution is in an oscillating fashion. The data such developed also indicate that there may be an optimum condition for the 300-year magnetic field variations centered on an intermediate period of the well-known approximate 11-years. A highly speculative attempt is made to show that this optimum condition based on the modulation of magnetic energy may have significant contributions from the self-sustained fusion processes in the energy generating region at the center of the Sun. Based on phenomenological observations it is further speculated that varying energy generated in the core is fed into the system on time scales indicative of pressure waves, global resonant acoustic oscillations, which by superposition of amplitudes will result in varying periodicities ranging from e.g. minutes to years.