1. IR Summary M. Sullivan For
M. Boscolo, K. Bertsche, E. Paoloni, S. Bettoni,
F. Bosi, P. Fabbricatore, S. Farinon, N. Carmignani,
P. Raimondi, M. Biagini, P. Vobly, I. Okunev,
A. Novokhatski, S. Weathersby, R. Cenci, A. Perez, et al.
SuperB General Meeting XVII
La Biodola, Isola d’Elba, Italy
May 28 - June 2, 2011

2. Outline Current IR design Beam backgrounds QD0 (and QF1)
Vibration budget and control
MDI issues (in case Eugenio missed something) and the next steps in the design
Summary

3. Present Parameters (V12 lattice)

4. Parameters used in the IR designs
Parameter HER LER
Energy (GeV)
Current (A)
Beta X* (mm
Beta Y* (mm
Emittance X (nm-rad)
Emittance Y (pm-rad)
Sigma X (m)
Sigma Y (nm)
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. Air-Core “Italian” Design
The shared QD0 and QF1 parts of the VP design are the air-core design
The QD0 and QF1 are 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

7. Air core “Italian” QD0, QF1

8. SR backgrounds No photons strike the physics window
We trace the beam out to 20 X and 45 Y
The physics window is defined as +/-4 cm for a 1 cm radius beam pipe
Photons from particles at high beam sigmas presently strike 7-10 cm downstream of the IP
However, the highest rate on the detector beam pipe comes from points that are a little farther away
This is true for both the vanadium permendur and the air-core design

9. Beam Backgrounds
Manuela Boscolo gave us an update on beam related backgrounds
BGB
Touschek
Coulomb
She mentioned that radiative Bhabhas and 2 photon e+e- production are the primary luminosity backgrounds
In summary the backgrounds are under control

12. Collimator settings are about 25-35 

13. Radiative Bhabhas
We had a presentation on backgrounds from radiative bhabhas from Alejandro Perez
A great deal of work has gone into simulating the beam line components
Magnetic fields but not yet material
Some “hot spots” have been identified and more work is needed to see how these might be reduced

16. Current IR Analysis Status
SR backgrounds are under control
However need to extend the SR beam scan out to at least 25 and check that the high sigma particle density is high enough
SR power inside the cryostats looks manageable
Also preliminary look at SR energy penetration
Beam-gas, Touschek and Coulomb backgrounds are under control
Collimator location ranges are about 25-35
Beta functions are reasonable
Vibration control has been studied
Preliminary designs for solenoid compensation completed
Magnetic fields (Bertsche)
Lattice corrections (Nosochkov)

17. QD0
Work is continuing toward building a prototype QD0 magnet (Eugenio’s talk)
Pasquale Fabbricatore and Stefania Farinon from Genoa are helping us design real magnets and cryostats
This is a major step forward. The design needs to be shaken down with just this type of work.

18. E. Paoloni

21. QD0 Field simulation
We had a very interesting presentation on the modeling of the QD0 field by Nicola Carmignani
This is a sophisticated simulation and will be very useful for developing more detailed dynamic aperture studies and the effect of the final focus elements on the dynamic aperture
From Nicola’s presentation

22. From Nicola’s presentationBz By Bx

23. Vibration Control for the FF and Measurements of the Tor Vergata Site Ground Motion
We had two very nice presentations on vibration control and measurements
Kirk Bertsche showed further analysis of the FF vibrations
Laurent Brunetti showed new data on ground motion measurements at Tor Vergata (John’s talk)

24. Vibration control for the FF
Kirk Bertsche refined his analysis of the vibration issues for the final focus magnets and what we need to achieve in motion control to keep the beams in collision – he now includes tolerances for the rest of the ring
One primary conclusion is that the Tor Vergata site is better than the Frascati site for vibration control at the IP
In addition, it has occurred to him that the source points for the synchrotron people may turn out to have the most stringent stability requirements – this should be checked

27. MDI and IR issues Cryostat size W shielding Rapid access
Vibration control
Cryostat supports
SVT supports
SVT services and signals
These are all inter-related as general MDI issues

28. IR Permanent magnet design details QD0 and QF1 design details
QD0H and QF1H Panofsky style design details
Anti-solenoid design details
Vacuum cooling, BPMs and assembly

29. Summary We have a design that is flexible and has good:
SR backgrounds
Beam backgrounds
Lattice functions
Beam apertures
The design options are:
Vanadium Permendur for QD0 and QF1
Parallel air-core dual quads for QD0 and QF1
Both designs include additional vanadium permendur Panofsky quads on the HER

30. Summary (2) The IR design demonstrates robustness
We have two separate QD0 designs
The direction of the beams can be either way with a weak preference for the incoming beams to be from the outside rings due to the location of the SR power on the cryostat beam pipe
The design has good beam energy flexibility
Tau-charm threshold should be rechecked
Different boost values

31. Summary (3) Good progress is being made on the design of the QD0
A prototype of the air-core design is being built
This will test the feasibility of the air-core design
Design details are encouraging a redesign of the IR – trying to maintain our overall parameter set
An overall vibration control design is being developed for the FF magnets. The measurements of the Tor Vergata site are very encouraging and the fact that the beams tend to move together with QD0 motion has significantly loosened the vibration tolerance requirements on cryostat motion

32. Conclusions The IR design is now getting feedback from design details
As engineering concerns are uncovered we will have to make modifications to the design but I believe this design has the room and robustness to respond to these demands