Measurements of solar magnetic element dispersal

被引：86

作者：

Berger, TE ^{[1
]}

Löfdahl, MG ^{[1
]}

Shine, RA ^{[1
]}

Title, AM ^{[1
]}

机构：

[1] Lockheed Martin Adv Technol Ctr, Palo Alto, CA 94304 USA

来源：

ASTROPHYSICAL JOURNAL | 1998年 / 506卷 / 01期

关键词：

Sun; faculae; plages; Sun : magnetic fields; Sun : photosphere;

D O I：

10.1086/306228

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

The dispersal of magnetic elements in the solar photospheric flow field is studied by tracking individual "magnetic bright points" (MBPs) identified in a G-band 4305 Angstrom filtergram time series obtained at the 50 cm Swedish Vacuum Solar Telescope on La Palma, Spain. The time series spans approximately 70 minutes with a field of view of 29 " x 29 " near disk center. All images in the time series are restored to near the telescope diffraction limit (similar to 0." 2 in the G band) using partitioned phase diverse speckle techniques. Regions of enhanced magnetic network and quiet Sun are examined. In the network region, automated tracking of individual MBPs reveals approximately Gaussian diffusion, with indications for slightly "superdiffusive" dispersal. The inferred Gaussian diffusion coefficient is 60.4 +/- 10.9 km(2) s(-1). In the quiet-Sun region, local correlation tracking velocity measurements show the dispersal of artificial tracers to be non-Gaussian over most of our data set with indications of an asymptotic approach to a 285 km(2) s(-1) Gaussian diffusion.

引用

页码：439 / 449

页数：11

共 37 条

[11] GONG observations of solar surface flows [J].

Hathaway, DH ;

Gilman, PA ;

Harvey, JW ;

Hill, F ;

Howard, RF ;

Jones, HP ;

Kasher, JC ;

Leibacher, JW ;

Pintar, JA ;

Simon, GW .

SCIENCE, 1996, 272 (5266) :1306-1309

[12] CAN THE FRACTAL DIMENSION OF IMAGES BE MEASURED [J].

HUANG, Q ;

LORCH, JR ;

DUBES, RC .

PATTERN RECOGNITION, 1994, 27 (03) :339-349

[13]

KOMM RW, 1995, SOL PHYS, V158, P213

[14] DIFFUSION OF MAGNETIC-FLUX ELEMENTS ON A FRACTAL GEOMETRY [J].

LAWRENCE, JK .

SOLAR PHYSICS, 1991, 135 (02) :249-259

[15] ANOMALOUS DIFFUSION OF MAGNETIC ELEMENTS ACROSS THE SOLAR SURFACE [J].

LAWRENCE, JK ;

SCHRIJVER, CJ .

ASTROPHYSICAL JOURNAL, 1993, 411 (01) :402-405

[16] TRANSPORT OF MAGNETIC FIELDS ON SUN [J].

LEIGHTON, RB .

ASTROPHYSICAL JOURNAL, 1964, 140 (04) :1547-&

[17] Preparation of a dual wavelength sequence of high-resolution solar photospheric images using phase diversity [J].

Lofdahl, MG ;

Berger, TE ;

Shine, RS ;

Title, AM .

ASTROPHYSICAL JOURNAL, 1998, 495 (02) :965-+

[18]

LOFDAHL MG, 1994, ASTRON ASTROPHYS SUP, V107, P243

[19]

LOFDAHL MG, 1996, THESIS U STOCKHOLM

[20]

Mosher J. M., 1977, THESIS CALTECH

← 1 2 3 4 →