Published March 1, 2017 | Version v1
Journal article

Convectively Driven Sinks and Magnetic Fields in the Quiet-Sun

  • 1. Instituto de Astrofísica de Andalucía (CSIC), Apdo. de Correos 3004, E-18080 Granada (Spain)
  • 2. National Solar Observatory, 3665 Discovery Drive, Boulder, CO 80303 (United States)
  • 3. Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, D-37077 Göttingen (Germany)
  • 4. Kiepenheuer-Institut für Sonnenphysik, Schöneckstr. 6, D-79104 Freiburg (Germany)

Description

We study the relation between mesogranular flows, convectively driven sinks and magnetic fields using high spatial resolution spectropolarimetric data acquired with the Imaging Magnetograph eXperiment on board Sunrise. We obtain the horizontal velocity flow fields of two quiet-Sun regions (31.2 × 31.2 Mm2) via local correlation tracking. Mesogranular lanes and the central position of sinks are identified using Lagrange tracers. We find 6.7 × 10 2 sinks per Mm2 in the two observed regions. The sinks are located at the mesogranular vertices and turn out to be associated with (1) horizontal velocity flows converging to a central point and (2) long-lived downdrafts. The spatial distribution of magnetic fields in the quiet-Sun is also examined. The strongest magnetic fields are preferentially located at sinks. We find that 40% of the pixels with longitudinal components of the magnetic field stronger than 500 G are located in the close neighborhood of sinks. In contrast, the small-scale magnetic loops detected by Martínez González et al. in the same two observed areas do not show any preferential distribution at mesogranular scales. The study of individual examples reveals that sinks can play an important role in the evolution of quiet-Sun magnetic features.

Availability note (English)

Available from http://dx.doi.org/10.3847/1538-4365/229/1/14

Additional details

Identifiers

Publishing Information

Journal Title
Astrophysical Journal, Supplement Series
Journal Volume
229
Journal Issue
1
Journal Page Range
[11 p.]
ISSN
0067-0049
CODEN
APJSA2

INIS

Country of Publication
United States
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
51034910
Subject category
S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
Descriptors DEI
CONVECTION; MAGNETIC FIELDS; PHOTOSPHERE; POLARIMETERS; SINKS; SPATIAL DISTRIBUTION; SPATIAL RESOLUTION; SPECTROSCOPY; SUN
Descriptors DEC
ATMOSPHERES; DISTRIBUTION; ENERGY TRANSFER; HEAT TRANSFER; MAIN SEQUENCE STARS; MASS TRANSFER; RESOLUTION; SOLAR ATMOSPHERE; STARS; STELLAR ATMOSPHERES