Internetwork Magnetic Fields Seen in Fe i 1564.8 nm Full-disk Images

Abstract

Abstract We studied the properties of internetwork magnetic fields in the solar photosphere, taking advantage of full-disk Stokes V/I maps of the Fe i 1564.8 nm line, which were obtained during 2010–2019. In contrast to most previous studies, we used data with moderate spatial and spectral resolutions. Nonetheless, we were able to distinguish the internetwork field components and the active region/network boundary components using large Zeeman splitting of the Fe i 1564.8 nm line. Thus, our analysis provides a point of view quite different from that of previous studies. We analyzed the data statistically without ordinary inversions, yet we successfully derived some properties of internetwork fields; the internetwork is filled with small-scale magnetic fields, their strength is within the weak field regime of the Fe i 1564.8 nm line (300–400 G or less), and the internetwork fields are highly inclined. Although the results were obtained from the analysis performed from a different perspective, they are consistent with the majority of previous findings. In addition, no notable variation in the properties of the internetwork fields was found during the period covering most of solar cycle 24.