SWOOPS (Solar Wind Observations Over the Poles of the Sun) Data

This data is equivalent to that put up at http://swoops.lanl.gov/jop-112/ by Dave McComas.  Two things have been added: (i) Markers showing the time distortion. (ii) An unshifted time scale.  These are explained below, after the first and second panels.

Ulysses SWOOPS data shifted in time back to the Sun using the "Constant Velocity Approximation".

The constant velocity approximation is used to project solar wind plasma data observed in situ at Ulysses back to the Sun. The assumption is that the solar wind speed is independent of radius. Using the radius of observation, the time it takes for the plasma to travel from the Sun (1 RSUN) to the radius of observation is computed and subtracted from the time the observation was made. This gives the origin time - the time plotted along the horizontal axis in this figure.     Markers appear in the proton speed (Vp) panel. These markers can be used to understand how time is distorted in the constant velocity approximation by comparing them with the corresponding markers below in the constant time shift mapping back to the Sun. Click here for a pdf file of the above.

Solar wind plasma data can also be mapped back to the Sun assuming  a constant speed for all the solar wind plasma independent of what speed was actually measured for that parcel. There is still a small amount of time distortion since the radius of Ulysses is changing with time (see Introduction for how the radius changes). However, the distortion is slight. The markers in the Vp panel here are therefore almost in the same relative positions as in the original data (note: there is a small data gap on 11 June so the marker that would lie in the gap is placed instead at the end of the gap). Therefore comparing the markers from this figure with those in the constant velocity approximation helps to understand  the time distortion introduced by the constant velocity approximation.     Along the bottom of this figure is the original observation time/date. Click here for a pdf file of the above.

Above is the magnetometer data mapped back to the Sun using the constant velocity approximation. The three components, in RTN coordinates, are shown. Top is the radial field, next is the meridional component defined so that it is zero if the field is radial, negative is that component point south, and positive if that component point north. Next is the azimuthal (east-west) component defined so that it is positive if it points west. Finally the total field magnitude is shown.  Click here for a pdf file of the above.

Solar wind magnetic field data can also be mapped back to the Sun assuming  a constant speed for all the solar wind plasma independent of what speed was actually measured for that parcel. There is still a small amount of time distortion since the radius of Ulysses is changing with time (see Introduction for how the radius changes). However, the distortion is slight.     Along the bottom of this figure is the original observation time/date. Click here for a pdf file of the above.

Finally, the data above is on anisotropies, the nonradial components of the flow vector, and the Alfven speed - here mapped back to the Sun using the constant velocity approximation. The parallel to perpendicular temperature is a very noisy number and not extremely reliable in an absolute sense. But, over this limited interval in time it probably gives a reasonable representation of relative variations. The flow vector can be used for many things. Here the azimuthal (phi) component seems to indicate the presence of a CIR. Click here for a pdf file of the above.

This is the same data as above but here mapped back to the Sun using the constant time interval shift corresponding to a flow speed of 360 km/s. Click here for a pdf file of the above.