Six wiggler lattice

November 27, 2002 Lattice: ~dlr/bmad_devel/6wigs/bmad_6wigs.lat

Lattice with 6 wigglers all in the east in configuration anticipated after Spring 2003 shutdown. There will be two adjacent 7 pole wigglers between Q13E and Q14E with opposite polarity. There will be an 8 pole wiggler between Q14E and Q15E, and 3 8 pole wigglers between Q18E and Q19E. Optics are designed so that phase advance from IP to L3 is half of total and so that alpha and etap are zero at L0 and L3. The IR superconducting quads and skew quads as well as Q3 and Q4 are east west symmetric. Quads Q27 and north are east west symmetric. Q5-Q26 are east west asymmetric.
Initial design is based on bmad style wiggler. East west symmetric sextupoles give near zero tonality, unit chromaticity and small 1-det

• lattice constraints
• Optical parameters and orbits
• table
• gif or png

December 10, 2002

Replace bmad simple wigglers with fitted field and symp_lie_bmad tracking and matrix calculation.The new lattice is dlr/bmad_devel/6wigs/bmad_6wig_fit_field.lat

The result is

• Distorted beta in the east. The distortion is most evident horizontally, presumably due to the horizontal nonlinearity of the wiggler that is not part of the simple bmad wiggler.
• Tonality is no longer near zero, but now a few kHz
• alpha* and beta* both horizontally and vertically are different for electrons and positrons This is first calculated with /nonlinearity/test using both twiss at start computed for electron and positron orbits respectively and then at least the tune difference was confirmed using nonlinearity. Subroutine electron_positron computes twiss parameters everywhere for particle= positron and then electron and is stored in nonlin%non_ele_pos_(i) and nonlin%ele_ele_(i) and constraints added to bmadz

With symmetric sextupoles, and using new constraints, set bmadz to clean up horizontal distortion in east, reduce difference in alpha* and beta* using quads.

January 6, 2003 Lattice: ~dlr/bmad_devel/6wigs/bmad_6wigs_1.lat

Go back to simple wigglers. Rework to minimize difference for electrons and positrons for beta*, alpha*, emittance, curly_d.

The result is pretty good

• lattice constraints
• Optical parameters and orbits
• table
• gif or png

February 28, 2003 Lattice: ~dlr/bmad_devel/6wigs/bmad_2_26_03.

Use sextupoles along with constraints to minimize differences. Then return to quadrupoles. Extend east west asymmetry of quads when find that it is high vertical beta at crossing points in B35E that are limiting.

• lattice constraints
• Optical parameters and orbits
  • table
  • Orbit, eta, beta plot png and ps
  • Tune scan png and ps and initialization , (earlier version bmad_2_18_03.) Starting point for tracking is 2.2mm,5um,3e-3
  • Dynamic aperture tracking png and ps Qx=0.54, Qy=0.6, Qs=-0.1
  • Dynamic aperture tracking png and ps Qx=0.54, Qy=0.58, Qs=-0.1
  • Tune scan png and ps and initialization , Starting point for tracking is 2.2mm,20um,6e-3
  • Dynamic aperture tracking png and ps Qx=0.54, Qy=0.615, Qs=-0.1

March, 18, 2003 Lattice: ~dlr/bmad_devel/6wigs/bmad_6wigs_3_18_03.lat

Replace layout, ~dlr/bmad_devel/6wigs/cesrc_6wig_mod_layout.bmad with ~dlr/bmad_devel/layout/cesr_c1_layout.bmad. The old layout had missing bend in both east and west. The new layout corresponds to geometry that scott will use to survey dipoles, quads, and wigglers in east. Also, in the previous, the chess wigglers had been inadvertently left on. Use all quads east and west independently in alternating groups to reoptimize.

• lattice constraints
• lattice
• Optical parameters and orbits
  • table
  • Orbit, eta, beta plot png and ps
  • Tune scan png and ps and initialization
  • Tune scan of bunch 1, train 1 positrons vs 9X5X0.0001mA/bunch electron png and ps and initialization Track for only 100 turns to check that splits for lrbbi are ok 4/4/03
  • Tune scan of bunch 1, train 1 positrons vs 9X5X0.0001mA/bunch electron png and ps and initialization Track for 1000 turns. Should be the same as scan with no parasitic crossings. 4/7/03.
  • Tune scan of bunch 1, train 1 positrons vs 9X4X1mA/bunch electron png and ps and initialization 4/7/03.
  • Dynamic aperture tracking png and ps Qx=0.54, Qy=0.615, Qs=-0.1
  • Dynamic aperture tracking (another tune) png and ps Qx=0.54, Qy=0.625, Qs=-0.1
  • Dynamic aperture tracking of bunch 1 positrons with 9X5X2ma/bunch of electrons png and ps and initialization Qx=0.54, Qy=0.6155, Qs=-0.1