Abstract Details

Affiliation: Ph.D scholar
Conference ID: ASI2017_1104
Title : Variation in Coronal Rotation with altitude
Authors and Co-Authors : Rupal Trivedi H. & H. B. Kotak Institute of Science, Rajkot, India. Som Kumar Sharma Physical Research Laboratory, Ahmedabad, India. Hari Om Vats Physical Research Laboratory, Ahmedabad, India.
Abstract Type : Poster
Abstract Category : Sun and the Solar System
Abstract : The coronal differential rotation is estimated by using the disk-integrated daily measurements of 11 frequencies: (275, 405, 670, 810, 925, 1080, 1215, 1350, 1620, 1755 MHz and 2800) MHz The data used from 1997 June 1–1999 July 31 and analyzed by flux modulation method. To obtain rotation period, Gaussian analysis for curve fitting of first secondary maxima of autocorrelogram is used. No results can be obtained easily from 275MHz and 405MHz due to noise in data of low frequencies. Best estimation can be achieved from curve fitting analysis. The rotation period is obtained by using earth based observations, thus the sidereal rotation period is calculated. Aschwanden & benz (1995) suggests that lower frequencies comes out from outer part of corona and higher frequencies comes out from inner part of corona. The investigations indicate that the sidereal rotation period at the highest frequency 2800 MHz is highest and lower frequencies have lower the rotation period. The difference is only ~1.4 days with increasing order. Hence, the conclusion is as altitude increases, the rotation period decreases in corona.