MAGNETIC LOOPS IN THE QUIET SUN

Journal Article · Wed Nov 10 04:00:00 EST 2010 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/723/2/L185· OSTI ID:21457030

Wiegelmann, T; Solanki, S K; Barthol, P; Gandorfer, A ^[1]; Borrero, J M; Schmidt, W ^[2]; Pillet, V MartInez; Bonet, J A ^[3]; Del Toro Iniesta, J C ^[4]; Domingo, V ^[5]; Knoelker, M ^[6]

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1. Max-Planck-Institut fuer Sonnensystemforschung, Max-Planck-Str. 2, 37191 Katlenburg-Lindau (Germany)
2. Kiepenheuer-Institut fuer Sonnenphysik, Schoeneckstr. 6, 79104 Freiburg (Germany)
3. Instituto de Astrofisica de Canarias, C/Via Lactea s/n, 38200 La Laguna, Tenerife (Spain)
4. Instituto de Astrofisica de Andalucia (CSIC), Apartado de Correos 3004, 18080 Granada (Spain)
5. Grupo de Astronomia y Ciencias del Espacio, Universidad de Valencia, 46980 Paterna, Valencia (Spain)
6. High Altitude Observatory, National Center for Atmospheric Research Boulder, CO 80307 (United States)

We investigate the fine structure of magnetic fields in the atmosphere of the quiet Sun. We use photospheric magnetic field measurements from SUNRISE/IMaX with unprecedented spatial resolution to extrapolate the photospheric magnetic field into higher layers of the solar atmosphere with the help of potential and force-free extrapolation techniques. We find that most magnetic loops that reach into the chromosphere or higher have one footpoint in relatively strong magnetic field regions in the photosphere. Ninety-one percent of the magnetic energy in the mid-chromosphere (at a height of 1 Mm) is in field lines, whose stronger footpoint has a strength of more than 300 G, i.e., above the equipartition field strength with convection. The loops reaching into the chromosphere and corona are also found to be asymmetric in the sense that the weaker footpoint has a strength B < 300 G and is located in the internetwork (IN). Such loops are expected to be strongly dynamic and have short lifetimes, as dictated by the properties of the IN fields.

• OSTI ID: 21457030
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 2 Vol. 723; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ASYMMETRY
ATMOSPHERES
CHROMOSPHERE
CONVECTION
ENERGY TRANSFER
HEAT TRANSFER
MAGNETIC FIELDS
MAIN SEQUENCE STARS
MASS TRANSFER
PHOTOSPHERE
RESOLUTION
SOLAR ATMOSPHERE
SPATIAL RESOLUTION
STARS
STELLAR ATMOSPHERES
SUN