Formation of Moving Magnetic Features and Penumbral Magnetic Fields

1. Formation of Moving Magnetic Features and Penumbral Magnetic Fields M. Kubo1,2, K. Ichimoto3, T. Shimizu2, S. Tsuneta3, Y. Suematsu3, Y. Katsukawa3, S. Nagata5, B. W. Lites1,Z. A. Frank6, T. D. Tarbell6, R. A. Shine6, A. M. Title6, and SOT team (1) HAO/NCAR, (2) ISAS/JAXA, (3) NAOJ, (4) ISAS/JAXA, (5) Kyoto U., (6) LMSAL MMFs with polarity opposite to the sunspot Abstract: The evolutions of vector magnetic fields of moving magnetic features (MMFs) are well observed with the Solar Optical Telescope aboard the Hinode satellite. We find that MMFs having relatively vertical fields with polarity same as the sunspot are detached from the sunspot penumbra around the granules appeared in the penumbra. This suggests that granular motions in the penumbra are responsible for the disintegration of the sunspot. The MMFs with polarity opposite to the sunspot are located at the outer edge of horizontal fields extending from the penumbra. This is an evidence that the MMFs with polarity opposite to the sunspot are prolongation of penumbral horizontal fields. We detect redshifts larger than sonic velocity in the photosphere for the MMFs with polarity opposite to the sunspot. • MMFs with polarity opposite to the sunspot appear at the outer • boundary of horizontal fields extending from the penumbra • (red arrows in the following figure). • MMFs with polarity opposite to the sunspot have large redshifts. • Some of such MMFs have redshifts larger than sonic velocity (~7km/s) • in the photosphere. 9 km/s fuzzy positive MMF negative MMFs Observation with Hinode/SOT • AR10933@S04°E11° • Spectro-polarimeter observation: • - full Stokes (IQUV) profiles • of Fe I 6301.5 & 6302.5Å • - 0.16”/pixel • - 24 scan steps with • 128s cadence • - duration: 1 hour • Magnetic field vector: • Milne-Edington inversion 81” 3.8” Wavelength [km/sec] MMFs detached from penumbral spine • Evolution of Stokes profiles • (Center of the green boxes) • - Stokes Q & U: • blueshift of 1km/s • no temporal change • - Stokes V: • redshift of 5 km/s • decrease with time • Penumbra spine (vertical component) branches off. • MMF having relatively vertical field with polarity same as • the sunspot is detached from the branch of penumbral spine. • The branch of penumbral spine is formed along the outer • edge of bright features (granular cells) in the penumbra. • Significant Doppler motions are not observed. time appearance of the MMF bright feature Discussions • Our observational result of the MMFs detached • from the penumbral spine suggests that • granules appeared in the penumbra remove • the magnetic flux (MMFs) from the penumbra. • The fact that the MMFs with polarity opposite • to the sunspot are located at the outer edge • of horizontal fields extending from the • penumbra is an evidence that such MMFs are • continuation of the penumbral fields. This • result supports the idea of a sea serpent • structure (e.g. Harvey & Harvery1973). • Stokes-V with large redshifts has apparently • larger signal than Stokes Q & U in the line wing • for MMFs with polarity opposite to the sunspot. • This means that such MMFs have more vertical • fields than the extending horizontal fields. moat region penumbra spine spine branch positive MMF MMF granular cell Horizontal field extending from the penumbra Downward motion negative MMF