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Here we report in depth reanalysis of a paper by Vats et al. (2001)[Astrophys. J. 548, L87] based on the measurements of differential rotationwith altitude as a function of observing frequencies (as lower and higherfrequencies indicate higher and lower heights, respectively) in the solarcorona. The radial differential rotation of the solar corona is estimated fromdaily measurements of the disc-integrated solar radio flux at 11 frequencies:(275, 405, 670, 810, 925, 1080, 1215, 1350, 1620, 1755 MHz and 2800 MHz). Weuse the same data as were used in Vats et al. (2001), but instead of the 12thmaxima of autocorrelograms used there, we use the 1st secondary maxima toderive the synodic rotation period. We estimate synodic rotation by Gaussianfit of the 1st secondary maxima. Vats et al. (2001) reported that the siderealrotation period increases with increasing frequency. The variation found bythem was from 23.6 to 24.15 days in this frequency range with a difference ofonly 0.55 days. The present study finds that sidereal rotation period increaseswith decreasing frequency. The variation range is from 24.4 to 22.5 days anddifference is about three times larger (1.9 days). However, at 925 MHz bothstudies give similar rotation period. In Vats et al. (2001) the Pearson factorwith trend line was 0.86 whereas present analysis obtained a ~ 0.97 Pearsonfactor with the trend line. Our study shows that the solar corona rotatesslower at higher altitudes, which is in contradiction to the findings reportedin Vats et al. (2001).  Key words: Solar radio flux- flux modulation method- Gaussian fit- siderealrotation period.

Variations in the Solar Coronal Rotation with Altitude - Revisited