3 papers
astro-ph.SR2023
Photospheric Velocities Measured at Mt. Wilson Show Zonal and Sectoral Flows Compose the Torsional Oscillations
Roger K. Ulrich, Tham Tran, John Boyden
The methods for reducing the observations from the 150-foot Tower Telescope on Mt.~Wilson are reviewed and a new method for determining the North/South (sectoral) and the East/West…
astro-ph.SR2018
Solar Sources of Interplanetary Magnetic Clouds Leading to Helicity Prediction
Roger K. Ulrich, Pete Riley, T. Tran
This study identifies the solar origins of magnetic clouds that are observed at 1 AU and predicts the helical handedness of these clouds from the solar surface magnetic fields. We…
astro-ph.SR2016
Generation of a North/South Magnetic Field Component from Variations in the Photospheric Magnetic Field
Roger K. Ulrich, Tham Tran
We address the problem of calculating the transverse magnetic field in the solar wind outside of the hypothetical sphere called the source surface where the solar wind originates.…