IR Design Status and Update

1. IR Design Status and Update M. Sullivan For M. Boscolo, K. Bertsche, E. Paoloni, S. Bettoni, F. Bosi, P. Fabbricatore, P. Raimondi, M. Biagini, P. Vobly, I. Okunev, A. Novokhatski, S. Weathersby, et al. SuperB Meeting XVII La Biodola, Isola d’Elba, Italy May 28 - June 2, 2011

2. Outline • Review of present IR design • Engineering input • Next Steps • Summary and Conclusions

3. Present Parameters? (V12 lattice)

4. Parameters used in the IR designs Parameter HER LER Energy (GeV) 6.70 4.18 Current (A) 1.89 2.45 Beta X* (mm 26 32 Beta Y* (mm 0.253 0.205 Emittance X (nm-rad) 2.00 2.46 Emittance Y (pm-rad) 5.0 6.15 Sigma X (m) 7.21 8.87 Sigma Y (nm) 36 36 Crossing angle (mrad) +/- 30

5. General IR Design Features • Crossing angle is +/- 30 mrads • Cryostat has a complete warm bore • Both QD0 and QF1 are super-conducting • PM in front of QD0 • Soft upstream bend magnets • Further reduces SR power in IP area • BSC to 30 in X and 100 in Y (7 fully coupled) • SR scanned to 20 in X and 45 in Y

6. Details of the permanent magnet slices • Z from IP Len. R1 R2 G • Name Beam m cm mm mm T/cm • QDPA LER 0.30 1 7.5 12.5 1.392 • QDPB LER 0.31 1 7.5 13.0 1.473 • QDPC LER 0.32 1 7.5 13.5 1.547 • QDPD LER 0.33 1 7.5 14.0 1.616 • QDPE LER 0.34 1 7.5 14.5 1.680 • QDPF LER 0.35 1 7.5 15.0 1.740 • QDPG LER 0.36 1 7.5 15.5 1.796 • QPDH drift 0.37 1 • QDPI HER 0.38 1 7.5 16.5 1.899 • QDPJ HER 0.39 1 7.5 17.0 1.945 • QDPK HER 0.40 1 7.5 17.5 1.989 • QDPL HER 0.41 1 7.5 18.0 2.030 • QDPM HER 0.42 1 7.5 18.5 2.070 • QDPN HER 0.43 1 7.5 19.0 2.107 • QDPO HER 0.44 1 7.5 19.5 2.142 • QDPP HER 0.45 1 7.5 20.0 2.175 • QDPQ HER 0.46 1 7.5 20.5 2.207 • QPDR HER 0.47 1 7.5 21.0 2.238 • QDPS HER 0.48 1 7.5 21.5 2.266

7. Vanadium Permendur Design • We allow for 3 mm of space for the coils (new information from Ivan – actually 2.6 mm) • The central steel section can be very thin because the magnetic field in the steel is nearly cancelled from the twin windings • The QD0 magnet is aligned as much as possible to the beam axis, however we must slant it with respect to the beam axis in order to accommodate the increasing horizontal size of the beam-stay-clear

8. Vanadium Permendur “Russian” Design

9. VP design details • PM as described earlier • Magnet QD0 QD0H QF1 QF1H • IP face (m) 0.55 0.90 1.25 1.70 • Length (m) 0.30 0.15 0.40 0.25 • Angle wrt beam (mrad) 13.33 0 2 1 • G (T/cm) 0.956 0.706 0.408 0.381 • Steel aperture (mm) 40 50 74 78 • Max. Field (T) 1.91 1.77 1.51 1.49

10. Air-Core “Italian” Design • We replace the shared QD0 and QF1 parts of the VP design with the air-core design • Also place QD0 and QF1 parallel to the detector axis • Then we have the same field strengths and the LER and HER pieces are the same strength as the VP design

11. Air core “Italian” QD0, QF1 Picture Out of Date

12. AC design details • PM as described above • Magnet QD0 QD0H QF1 QF1H • IP face (m) 0.55 0.90 1.25 1.70 • Length (m) 0.30 0.15 0.40 0.25 • Axis offsets (mm) 0.5 --- 4 --- • Angle wrt beam (mrad) 30 0 27 1 • G (T/cm) 0.956 0.706 0.408 0.381 • Aperture (mm) 35 50 73 78 • Max. Field (T) 1.67 1.77 1.49 1.49

13. SR power (VP design) 115 52 8 295 56 17 42 32 390 205

14. SR power (AC design) 115 57 8 311 57 17 43 35 402 215

15. Current IR Analysis Status • SR backgrounds are under control • SR power inside the cryostats looks managable • Beam-gas, Touschek and Coulomb backgrounds are under control (see Manuela’s talk) • Beta functions are reasonable • Preliminary designs for solenoid compensation • Magnetic fields (Bertsche) • Lattice corrections (Nosochkov)

16. SVT and MDI • Good progress • Filippo Bosi has developed an initial layout of SVT hardware and has an initial design of the Be beam pipe with vacuum connecting flanges • Cable layout and how the SVT signals and power lines get in and out needs to be developed • The W shield (with/without) noses also needs to be incorporated

17. Next Steps in the IR Design • Permanent Magnet Study • Model the PM slices and make sure that the design parameters can be achieved • Computer model used for the PEP-II magnets can tell us dimensional, positional and strength tolerances • Mechanical engineer to design fixturing for magnet slice assembly and installation

18. Cryostat Design • Pasquale Fabbricatore has taken a first look at the cryostat and magnet designs (presentation follows) • We may need to give him more space • Probably more z space – this will alter the magnet designs • Need to generate a new IR design with these engineering constraints • Need to get an initial estimate because this impacts the inner diameter of the DCH

19. Cryostat supports • Need an engineer to start looking at how the cryostats are supported • Involves the detector steel and how we get rapid access to the SVT and central Be chamber • Vibration control • Also involves how the cryogenic plant hooks up to the cryostats – can we keep the cryostats cold when performing a rapid access

20. Summary • We have a good IR design that meets our requirements • Now we welcome the engineers that can come in and tell us what is impossible • Then we need to decide how to change the design with the guidance of the engineers so we can still build what we want • We may have to compromise some of the IR parameters…

21. Conclusion • We are at a good starting point • The parameter space of the IR has been studied fairly thoroughly giving us some sense of possible change directions • The next round is to now work with the engineers and together figure out how we can actually build what we want and need • This also involves the detector so stick around for the next session!