Correlated Quasiperiodic Pulsations in Type III Radio Bursts and Solar EUV Emission, Jetlets and Magnetic Fields: Comparisons of Intervals with and without Type III Storms

Abstract Solar p -modes are ∼5 minute acoustic waves, which can be used as helioseismological diagnostics of the Sun’s subsurface. Recent studies relate them to quasiperiodic pulsations (QPPs) identified in X-rays, radio waves, and extreme ultraviolet (EUV) emission. QPPs with ∼5 minute periods have been simultaneously observed in Solar Dynamics Observatory (SDO) EUV measurements and Parker Solar Probe (PSP) observations of Type III radio storms, suggesting a link between p -modes and electron acceleration. Using examples when potential field source surface mapping indicated that PSP and SDO were magnetically connected, we compared periodicities in intervals with (“loud”) or without (“quiet”) coincident Type III radio storms, and looked for small jets (jetlets), as indicators of open field lines enabling electrons to escape and produce radio waves. QPPs of 3–10 minutes occurred in EUV and Helioseismic and Magnetic Imager (HMI) data in all intervals. Whereas the p -mode amplitudes in photospheric EUV and HMI data were similar in “quiet” and “loud” events, amplitudes in coronal EUV waves were approximately an order of magnitude larger during “loud” intervals. The jetlet rate was comparably higher during “loud” times, consistent with the low corona as the source of electron beams producing Type III waves. The larger EUV amplitudes and higher jetlet rates during “loud” intervals indicate that the presence of electron acceleration along open field lines depends strongly on QPP magnitude and the associated magnetic field configuration. These findings provide new insights into the conditions under which p -mode energy can leak from the photosphere into the corona.