Spectroscopic determinations of solar rotation

  title={Spectroscopic determinations of solar rotation},
  author={Robert Howard and J. W. Harvey},
  journal={Solar Physics},
Spectral line shift data obtained from full-disk magnetograms recorded at Mt. Wilson are analyzed for differential rotation. The method of analysis is discussed and the results from the data for 1966 through 1968 are presented. The average equatorial velocity over this period is found to be 1.93 km/sec or 13.76 deg/day (sidereal). This corresponds to a sidereal period of 26.16 days. The average results areω = 2.78 × 10-6 - 3.51 × 10-7 sin2B - 4.43 × 10-7 sin4B rad/sec, whereB is the solar… 

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