Phase space ellipses

Figure 13. Two-dimensional phase space ellipse representing the spatial and angular deviation of the electron beam in the (vertical) and direction. Note that the shape of the ellipse is upright at z = 0 (a) but changes at different points of the ring say at z = 1 (b) but the area is conserved. If a slit (SQ and Su) is placed at the z = 1 position, it can be projected back to the origin, (c) and (d) show the same transformation. Note that the area intersected by the slit boundaries is also conserved. The synchrotron light ellipse (SR) is also shown. [Used by permission of the editor, Springer-Verlag, from Gudat (1979), Fig. 3.7, p. 68]...

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