Latitudinal dependence of supergranular Area and Fractal dimension

Authors

  • Paniveni Udayashankar Inter University centre for Astronomy and Astrophysics

DOI:

https://doi.org/10.18063/eoaa.v2i1.347

Keywords:

Sun, granulation-Sun, activity-Sun, photosphere

Abstract

Abstract: A dependence of the area of supergranular cells with respect to the Latitude is studied and it is found that the cells are situated symmetrically about the ±250 latitude.

Fractal dimension of the supergranular cells also shows a marginal latitudinal dependence, variation being in the range 1.6–1.7 in the latitudinal limits of ±300. Fractal dimension D for supergranulation is obtained according to the relation P ∝ AD/2 where ‘A is the area and ‘P’ is the perimeter of the supergranular cells. A difference in the fractal dimension between the active and quiet region cells is noted which is conjectured to be due to the magnetic activity level.

Supergranular cells are essentially a manifestation of convective phenomena. They can shed light on the physical conditions in the convection zone of the Sun. Moreover, supergranules play a key role in the transport and dispersal of magnetic fields as it is an important step in our quest to understand the solar cycle.

Author Biography

Paniveni Udayashankar, Inter University centre for Astronomy and Astrophysics

Name: Dr. PANIVENI UDAYASHANKAR
Designation: Professor in the Department of Physics

Academic Honors and Distinctions:
• Recipient of National Merit Scholarship throughout academic career.
• Won a Rotary award and a shield for my school, St.Joseph’s Girls High School in Bellary based on the performance in the 10th grade (SSLC).
• Rank holder throughout SSLC, B.Sc. and M.Sc.
50th rank in SSLC for the state of Karnataka, 4th rank in Final B.Sc at the
Karnatak University, 1st rank in Solid State Physics branch in M.Sc.
• Selected as ‘Research Associate Of Inter-University centre for Astronomy and Astrophysics (IUCAA) Pune, India’ from 1st Aug 2007 till date.
• My name is entered into the 10th Edition of ‘Who’s Who of International and Business Women’ for achievements in Science and Music , published by the ‘American Biographical Society’, America.            

• Indragandhi Sadbhavana Gold medal award for ‘Research and Education’ in view of outstanding contribution and service to the nation, instituted by ‘Global Economic Progress and Research Association’, India.                                                                      

• Travel grants received for attending international conferences abroad from ‘CSIR’, ‘INSA’, ‘COSTED’, ‘AICTE’ and International Funding bodies such as IAU etc.                                                                          

• Recognized as Research Guide in Physics by VISVESVARAYA Technological University, Belgaum, Karnataka, India.

Work experience:
1. Worked as a JRF for 6 months at II Sc., Bangalore for a project ‘Characterization of ultra-thin oxide layer in Schottky barrier Solar cells’.
2. Teaching Experience : 33 years of Teaching Physics at the undergraduate level , graduate level and Postgraduate level.
3. Administrative Experience : Worked as In-charge Principal a few times between 2009 and 2011. Professor and HOD for 2 year and 8months between 2009 and 2011.

4. Fifteen Years of Research Experience
Completed part-time research work at the Indian Institute of Astrophysics, Koramangala, Bangalore-34, under the guidance of Prof.Jagdev Singh and Prof. Vinod Krishan.
5. Worked for a very short term funded research project in the field of solar supergranulation at the Observatory of ‘Cote de Azur’ , Nice , France in 2005.
6. Worked for a short term funded research project on ‘activity dependence of solar supergranular fractal dimension’ using Ca II K Kodaikanal data at Indian Institute of Astrophysics, Koramangala, Bangalore – 34 in 2008.
7. Conducted a comprehensive viva in April 2014 for the student ‘Punith Kumar V.’, a registrant of VTU for research on the topic ‘Growth and investigation of structural, electrical transport and magnetic properties of Bismuth based multiferroic perovskite-oxide’
8. Evaluated the thesis titled ‘Study of Solar chromospheres’ : Variation of Ca K line profiles with Solar cycle’ in November 2015 submitted by the student G. Sindhuja who had worked at Indian Institute of Astrophysics and registered with Mangalore University.
9. Conducted the final Ph.d viva of the student ‘G.Sindhuja’ on 29th Jan 2016 at the department of physics, Mangalore University.
10. Guiding three students for Ph.D

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Published

2018-02-26

Issue

Vol 2, No 1 (Published)

Section

Original Research Articles

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