1. Magnet design issues and discussion David Harding for Vladimir Kashikhin 3 April 2005

2. Electron Model FFAG Magnet Design Issues 2 Very early thoughts First notions of requirements Challenges A concept More questions To be continued tomorrow morning

3. 3 April 2005 Electron Model FFAG Magnet Design Issues 3 Magnet types One combined function magnet One quadrupole magnet –Carol says Fermilab Linac quad with new coils is good for this

4. 3 April 2005 Electron Model FFAG Magnet Design Issues 4 Fermilab Linac quad

5. 3 April 2005 Electron Model FFAG Magnet Design Issues 5 General requirements Slot length –100 mm Aperture (good field) –50 mm wide –25 mm high Also –Space for BPM –Make up vacuum –And so forth

6. 3 April 2005 Electron Model FFAG Magnet Design Issues 6 Magnetic needs Integrated dipole –Fixed strength –5 T-mm ( 1kG x 5 cm) Integrated quadrupole –Adjustable strength –Up to 0.2 T-mm/mm (1 kG/2.5 cm x 5 cm) Field uniformity –+/- 1%

7. 3 April 2005 Electron Model FFAG Magnet Design Issues 7 Challenges Aspect ratio (gap to length) Squeeze so much into such a short slot Current density Getting the heat out End field

8. 3 April 2005 Electron Model FFAG Magnet Design Issues 8 Concept Power the dipole component with permanent magnets –Compact –No power issues Power the quadrupole component with a (modified) Panofsky coil –Compatible with rectangular aperture –Relatively short ends

9. 3 April 2005 Electron Model FFAG Magnet Design Issues 9 First look – dipole only field lines

10. 3 April 2005 Electron Model FFAG Magnet Design Issues 10 Dipole plus quad field lines

11. 3 April 2005 Electron Model FFAG Magnet Design Issues 11 By(x)

12. 3 April 2005 Electron Model FFAG Magnet Design Issues 12 Questions Is this dipole field adequate? If BL if fixed, can we vary L (and B)? Is this quadrupole gradient adequate? Can we reduce the range of gradients? What magnet spacing is really required?