Volume 3,Issue 1
Fall 2023
A Study of Supergranulation through Its Parameters
Supergranulation is examined through its various parameters such as Area, perimeter, circularity and fractal dimension. A connection amongst these parameters throws light on the turbulent aspect of this convective feature. Area and perimeter at various latitudes are also studied in detail. The spread shows an asymmetric dispersion with a minimum dimension at around ±25º because there is a theoretical calculation which indicates that the enhanced fields will reduce the supergranular cell sizes (Chandrasekhar, 1961) around these latitudes. A different technique of analysis on a larger sample could consolidate these findings.
1. Noyes R W. The Sun, Our Star (Harvard University Press,1982).
2. Berrilli F, Florio A, Ermolli I. On the geometrical properties of chromospheric network. Solar physics 1998; 180 (1-2): 29-45
3. Berrilli F, Ermolli I, Florio A, Pietropaolo E . Average properties and temporal variations of the geometry of solar network cells. Astronomy and Astrophysics 1999 ; 344: 965-972.
4. Chandrashekar S, Hydrodynamic and Hydromagnetic stability (Clarendon Press, Oxford 1961).
5. De Rosa Marc L, Toomre J. Evolution of solar supergranulation. ApJ 2004; 616 /2 1240-1260
6. Ermolli I , Berrilli F, Florio A, and Pietropaolo E. : Chromospheric Network Properties Derived from One Year of PSPT Images.in Synoptic Solar Physics: 18th NSO/SP Summer Workshop, Sunspot New Mexico, 9-12 September, 1997. K.S. Balasubramaniam, J.W. NSO Publications, 1985-1999 Page 52 Harvey, and D.M. Rabin, eds. (Astron. Soc. Pacific), 223-230
7. Gilman P A : in S. Jordan (ed.), The Sun as a Star. NASA SP 1981; 450: 231.
8. Harvey K L: in R J Rutten and C J Schrijver (eds.). Solar Surface Magnetism, Kluwer Academic Publishers, Dordrecht,The Netherlands, 1994; 347.
9. Krishan V. A model of solar granulation through inverse cascade, MNRAS 1991 ; 250:50-53
10. Krishan V. Structure of Turbulence in the Solar Convection Zone. BASI 1996; 24(2): 285-289.
11. Krishan V, Paniveni U, Singh J, Srikanth R. Relationship between horizontal flow velocity and cell size for supergranulation using SOHO Dopplergrams, MNRAS 2002 : 334(1) : 230-232
12. Leighton R B, Noyes R W, Simon G W. Velocity fields in the solar atmosphere. Astrophysical Journal 1962; 135: 474.
13. Meunier N. Fractal Analysis of MDI Magnetograms: A contribution to the study of the formation of Solar Active Regions. Astrophysical Journal 1999; 515 (2): 801-811.
14. Meunier N, Complexity of magnetic structures: Flares and cycle phase dependence. Astronomy and Astrophysics, 2004: 420 (1), 333-342.
15. Paniveni U, Krishan V, Singh J, Srikanth R. Relationship between horizontal flow velocity and cell lifetime for supergranulation from SOHO Dopplergrams. Monthly Notices of Royal Astronomical Society 2004: 347, 1279-1281.
16. Paniveni U, Krishan V, Singh J, Srikanth R. On the fractal structure of Solar Supergranulation. Solar Physics 2005; 231: 1-10.
17. Paniveni U, Krishan V, Singh J, Srikanth R. Activity dependence of solar supergranular fractal dimension. Monthly Notices of Royal Astronomical Society 2010; 402(1): 424-428.
18. Raju K P, Srikanth R, Singh J. The Dependence on chromospheric Ca II K network cell sizes on solar latitude. Solar Physics 1998; 180 (1-2): 47-51.
19. Rimmele T, Schroter E. Variation of the cell size and velocities of the supergranulation with Heliographic Latitude. Astronomy and Astrophysics 1989; 221: 137-145.
20. Singh J, Bappu M K V. A dependence on solar cycle of the size of Ca+ network. Solar Physics 1981; 71: 161.
21. Srikanth R. Chapter 3. Ph.D Thesis 1999: Indian Institute of Science.
22. Srikanth R, Singh J, Raju K P. Distribution of Supergranular sizes. ApJ 2000; 534: 1008-1019
23. Sykora J. Time and shape changes of supergranular network. Solar physics 1970; 13 (2): 292-300.