MESOGRANULATION AND THE SOLAR SURFACE MAGNETIC FIELD DISTRIBUTION

Journal Article · Tue Feb 01 04:00:00 EST 2011 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/727/2/L30· OSTI ID:21560547

Yelles Chaouche, L; Moreno-Insertis, F; MartInez Pillet, V; Bonet, J A ^[1]; Wiegelmann, T; Barthol, P; Gandorfer, A; Solanki, S K ^[2]; Knoelker, M ^[3]; Bellot Rubio, L R; Del Toro Iniesta, J C ^[4]; Schmidt, W ^[5]

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1. Instituto de Astrofisica de Canarias, Via Lactea, s/n, 38205 La Laguna (Tenerife) (Spain)
2. Max-Planck-Institut fuer Sonnensystemforschung, Max-Planck-Strasse 2, 37191 Katlenburg-Lindau (Germany)
3. High Altitude Observatory (NCAR), Boulder, CO 80307 (United States)
4. Instituto de Astrofisica de Andalucia (CSIC), Glorieta de la Astronomia, s/n 18008 Granada (Spain)
5. Kiepenheuer-Institut fuer Sonnenphysik, 79104 Freiburg (Germany)

The relation of the solar surface magnetic field with mesogranular cells is studied using high spatial ({approx}100 km) and temporal ({approx}30 s) resolution data obtained with the IMaX instrument on board SUNRISE. First, mesogranular cells are identified using Lagrange tracers (corks) based on horizontal velocity fields obtained through local correlation tracking. After {approx}20 minutes of integration, the tracers delineate a sharp mesogranular network with lanes of width below about 280 km. The preferential location of magnetic elements in mesogranular cells is tested quantitatively. Roughly 85% of pixels with magnetic field higher than 100 G are located in the near neighborhood of mesogranular lanes. Magnetic flux is therefore concentrated in mesogranular lanes rather than intergranular ones. Second, magnetic field extrapolations are performed to obtain field lines anchored in the observed flux elements. This analysis, therefore, is independent of the horizontal flows determined in the first part. A probability density function (PDF) is calculated for the distribution of distances between the footpoints of individual magnetic field lines. The PDF has an exponential shape at scales between 1 and 10 Mm, with a constant characteristic decay distance, indicating the absence of preferred convection scales in the mesogranular range. Our results support the view that mesogranulation is not an intrinsic convective scale (in the sense that it is not a primary energy-injection scale of solar convection), but also give quantitative confirmation that, nevertheless, the magnetic elements are preferentially found along mesogranular lanes.

• OSTI ID: 21560547
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 2 Vol. 727; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ATMOSPHERES
DISTANCE
DISTRIBUTION
FABRICATION
FUNCTIONS
GRANULATION
MAGNETIC FIELDS
MAGNETIC FLUX
MAIN SEQUENCE STARS
PHOTOSPHERE
PROBABILITY DENSITY FUNCTIONS
SOLAR ATMOSPHERE
STARS
STELLAR ATMOSPHERES
SUN
SURFACES