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Title: Observational Evidence of a Flux Rope within a Sunspot Umbra

Abstract

We observed an elongated filamentary bright structure inside the umbra of the big sunspot in active region NOAA 12529, which differs from the light bridges usually observed in sunspots for its morphology, magnetic configuration, and velocity field. We used observations taken with the Solar Dynamic Observatory satellite to characterize this feature. Its lifetime is 5 days, during which it reaches a maximum length of about 30″. In the maps of the vertical component of the photospheric magnetic field, a portion of the feature has a polarity opposite to that of the hosting sunspot. At the same time, in the entire feature the horizontal component of the magnetic field is about 2000 G, substantially stronger than in the surrounding penumbral filaments. Doppler velocity maps reveal the presence of both upward and downward plasma motions along the structure at the photospheric level. Moreover, looking at the chromospheric level, we noted that it is located in a region corresponding to the edge of a small filament that seems rooted in the sunspot umbra. Therefore, we interpreted the bright structure as the photospheric counterpart of a flux rope touching the sunspot and giving rise to penumbral-like filaments in the umbra.

Authors:
;  [1];  [2]
  1. Dipartimento di Fisica e Astronomia—Sezione Astrofisica, Università di Catania, Via S. Sofia 78, I-95125 Catania (Italy)
  2. INAF—Osservatorio Astrofisico di Catania, Via S. Sofia 78, I-95125 Catania (Italy)
Publication Date:
OSTI Identifier:
22654394
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 846; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CHROMOSPHERE; CONFIGURATION; FILAMENTS; LIFETIME; MAGNETIC FIELDS; PHOTOSPHERE; PLASMA; SATELLITES; SUN; SUNSPOTS; VELOCITY; VISIBLE RADIATION

Citation Formats

Guglielmino, Salvo L., Zuccarello, Francesca, and Romano, Paolo, E-mail: salvo.guglielmino@oact.inaf.it. Observational Evidence of a Flux Rope within a Sunspot Umbra. United States: N. p., 2017. Web. doi:10.3847/2041-8213/AA835C.
Guglielmino, Salvo L., Zuccarello, Francesca, & Romano, Paolo, E-mail: salvo.guglielmino@oact.inaf.it. Observational Evidence of a Flux Rope within a Sunspot Umbra. United States. doi:10.3847/2041-8213/AA835C.
Guglielmino, Salvo L., Zuccarello, Francesca, and Romano, Paolo, E-mail: salvo.guglielmino@oact.inaf.it. Sun . "Observational Evidence of a Flux Rope within a Sunspot Umbra". United States. doi:10.3847/2041-8213/AA835C.
@article{osti_22654394,
title = {Observational Evidence of a Flux Rope within a Sunspot Umbra},
author = {Guglielmino, Salvo L. and Zuccarello, Francesca and Romano, Paolo, E-mail: salvo.guglielmino@oact.inaf.it},
abstractNote = {We observed an elongated filamentary bright structure inside the umbra of the big sunspot in active region NOAA 12529, which differs from the light bridges usually observed in sunspots for its morphology, magnetic configuration, and velocity field. We used observations taken with the Solar Dynamic Observatory satellite to characterize this feature. Its lifetime is 5 days, during which it reaches a maximum length of about 30″. In the maps of the vertical component of the photospheric magnetic field, a portion of the feature has a polarity opposite to that of the hosting sunspot. At the same time, in the entire feature the horizontal component of the magnetic field is about 2000 G, substantially stronger than in the surrounding penumbral filaments. Doppler velocity maps reveal the presence of both upward and downward plasma motions along the structure at the photospheric level. Moreover, looking at the chromospheric level, we noted that it is located in a region corresponding to the edge of a small filament that seems rooted in the sunspot umbra. Therefore, we interpreted the bright structure as the photospheric counterpart of a flux rope touching the sunspot and giving rise to penumbral-like filaments in the umbra.},
doi = {10.3847/2041-8213/AA835C},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 846,
place = {United States},
year = {Sun Sep 10 00:00:00 EDT 2017},
month = {Sun Sep 10 00:00:00 EDT 2017}
}