Abstract We revisit an existing but unexplored finding on the calculation of the baseline (i.e., potential) magnetic energy in observed solar magnetic configurations and apply it to two series of high-cadence, cospatial, and cotemporal line-of-sight photospheric magnetograms with a factor of ∼4 difference in spatial resolution. The target is a small coronal hole, ∼80″across. We find significant differences between the two data sets, with approximate factors of 2.4 in the unsigned magnetic flux, 2.1 in the potential magnetic energy, and 5.2 in the mean amplitudes of the energy variation, all in favor of the higher-resolution magnetograms. Additionally, we find a factor of 2.5 difference in the characteristic magnetic flux replenishment time, with configurations at higher resolution renewing their flux every 46 minutes on average. Energy decreases associated with apparent magnetic flux cancellation events in higher resolution yield power densities above 106erg cm−2s−1, seemingly sufficient to sustain coronal holes and drive the fast solar wind. For the first time, this represents apparent energy released at photospheric altitudes rather than energy deposited via the Poynting flux. Lower-resolution magnetograms give 5.4 times less power density output. These intriguing results could have wide-ranging implications for in situ solar wind measurements and their solar sources in the Parker Solar Probe mission, as well as for high-resolution observations featuring simultaneous photospheric and chromospheric magnetograms including, but not limited to, data from the Daniel K. Inouye Solar Telescope.
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Magnetic Outbreak Associated with Exploding Granulations
Abstract Diagnosing the spatiotemporal pattern of magnetic flux on the Sun is vital for understanding the origin of solar magnetism and activity. Here, we report a new form of flux appearance, magnetic outbreak, using observations with an extremely high spatial resolution of 0.″16 from the 1.6 m Goode Solar Telescope at the Big Bear Solar Observatory. Magnetic outbreak refers to an early growth of unipolar magnetic flux and its later explosion into fragments, in association with plasma upflow and exploding granulations; each individual fragment has flux of 10 16 –10 17 Mx, moving apart with a velocity of 0.5–2.2 km s −1 . The magnetic outbreak takes place in the hecto-Gauss region of pore moats. In this study, we identify six events of magnetic outbreak during 6 hr observations over an approximately 40″ × 40″ field of view. The newly discovered magnetic outbreak might be the first evidence of the long-anticipated convective blowup.
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- PAR ID:
- 10389463
- Date Published:
- Journal Name:
- The Astrophysical Journal Letters
- Volume:
- 942
- Issue:
- 1
- ISSN:
- 2041-8205
- Page Range / eLocation ID:
- L3
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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