1. KEK IR status
Shuji Tanaka
KEK
DEPFET workshop 2011/2/7-9 1

2. Latest design of IP chamber
Straight section
Kohriki
Very simple Be structure
Cooling route is change (back) to feed forward type
Worry for cooling dead region (end point of IP)
Forward manifold is placed on crotch part
Be part is only within “Physics window” .
-> other region can add materials (ex 100um Au for SR)
Be structure is simple barrel type -> very cheap 2

3. Narrow Space issue between PXD and IP
At present, it seems that we can avoid space problem by
optimizing beam pipe shape( still should pay attention) 3

4. Cooling test mockup
Nakayama

5. Connection technology choice
Brazing
Be: 1M yen
EBW or Brazing
EBW
Weak point by EBW
HIP: Hot lsostatic Pressing
HIP
EBW: Electron Beam Welding
Be: 34M yen
Pros. : very simple structure and cheap Be part
Cons. : Be-SUS region face with vacuum part 5

6. Tests before IP chamber production
Mechanical analysis of beam pipe (KEK)
Mockup production of crotch part by Al.
To evaluate howto make sawtooth structure
Ta-SUS HIP welding test production
Brazing test
EBW test -> to see thermal effects of pipe (deformation, vacuum sealing)
Be part test production (NGK insulators Co. Lid.)
Check the precision of structure
-> cut into some pieces
Be-SUS Connection test next year (before next summer) 6

7. Mechanical analysis Deformation by self weight Koike
equivalent stress ：Max 22MPa
　　　　　　　(support point)
Deformation：Max　0.0082mm
Support point : End of flange and
+/- 350 mm from IP 拡大
Near IP
equivalent stress ：Max 1.2MPa

8. Mechanical analysis (cantilever)
equivalent stress ：Max 176MPa
Deformation ：Max　6.7mm
equivalent stress Max

9. Mechanical analysis Self weight + coolant pressure 10atm IP region
equivalent stress ：Max 93MPa
変位：Max　0.014mm Be
Equivalent stress：Max42MPa
Deformation：Max　～0.011mm

10. Ta-SUS HIP welding test production
1, make Ta-SUS HIP (diffusion bonding) test pieces 2, applying thermal stress by EBW 3, check the vacuum level and mechanical deformation (This procedure will be used on joining ,inner and outer pipes)

11. Mockup production of crotch part by Al
In order to evaluate the production procedures how to cut inside(Saw tooth) of crotch part beam pipe. ->will be finish before the end of Mar.

12. IR design (top view:KEK)
BPM move to
QC side
Japan group will take care and assemble SVD 3rd layer
KEK: CDC design, Endflange, Beam pipe SVD endring, SVD 3rd

13. Immanuel Gfall (HEPHY Vienna)
Space Requirement SVD
Two types of design(Vienna and KEK) will be discussed on next B2GM
18 November 2010
Immanuel Gfall (HEPHY Vienna) 13

14. IR design (side view) We start discussion about bracket
of beam pipe now.

15. Space allocation of inner tracker
Heavy Metal
support
End flange (Ta?)
End ring
Some suspension
Structure for beam pipe
IP flange position
CFRP 1mm
Total weight will be ~100kg

16. End-Flange prototyping
This bracket has a role of shielding
Material: Heavy Metal (>1.5cm t) 16

17. SVD installation

18. SVD installation
Kohriki

19. SVD installation (mechanics)

20. QCS-SVD-joint Pin（φ10） Main block Long pipe（M8） Clamp（ M8ナット）
SVD could be kept by CDC by releasing Pin.
(to be Independent with QC cryostat)
Kohriki 20

21. SVD Mechanical Analysis
equivalent stress：Max 25MPa
Deformation：Max　0.015mm
Mechanical distortion is enough small
＝SVD can keep structure by sustain each end
最大主応力：Max 15MPa

22. SVD+IR installation procedure
Find a solution for installing this IR structure.
~ Establish a reasonable procedure to connect vacuum chamber flanges.
Belle II is fully equipped.
IP chamber is supported by SVD frame.
SVD is supported by CDC.
QCS cryostats can move out.
Connection flanges for vacuum chambers.
Top view
Little work space to access flanges.
It is impossible to connect flanges in this configuration.
Some work spaces to access flanges.
It will be possible to make use of these spaces.

23. DISCUSSION ITEMS 23

24. Touschek BG estimation ( High energy neutron BG) http://kds. kek

26. Ohnishi

29. Nakayama

31. Photonuclear peak

32. BEAST Operation (idea)
The baseline of BEAST II operation is no collision of beams, because of no Belle magnetic field.
Preparing new solenoid magnet to study BG level.(just idea)
Inner diameter ~60 cm
setup some radiation monitors
Need more cost ~ 1 Oku-en.
Difficulty shaping outer magnetic field (need return yoke?)
KEKB group prefer to use Belle detector because of easiness of operation-> schedule will delay 1~1.5 years

33. CO2 cooling
We had meeting with KEK cryogenic group about CO2 cooling last month.
They said:
The cooling power of CO2 system should be less than 3 Reitou- tons( Japanese unit: it means pumping power should be less than 7.5 kW, and parallel ). If our system satisfy this requirement, there are no limitation for system production.
If our system power will be higher than requirement, we need permission for each sub-parts.
KEK group agree to maintain CO2 system on Belle II operation,
then it is better to start discussing about our system outline and schedule (Next B2GM).

34. Summary The basic design of beam optics is finished
Inner structure of beam pipe is almost fixed (on schedule).
Still need Sawtooth optimization (beam test on next year)
Space assignment with PXD and SVD should be discuss in detail (in particular near 3rd layer SVD)
Mechanical analysis estimation and connection test (IP) (OK)
Vacuum test on Be-SUS connection (within 1 year)
Mockup production (crotch part)
BEASTII and neutron simulation discussion are started
There are still some open issues (cabling, cooling) 34

35. Schedule ~2011 Mar. Mechanical design and joint test
Mockup production of crotch part
2011-
Mechanical design fix (Ridge(Sawtooth), cooling…)
Optimizing production procedure
Service space allocation
SR beam test (May and July:X-ray keV)
2012
Beam pipe production
2013
IR Assembly 35

36. bkup 36

37. General IR design IR design based on Nano-beam scheme
Beam energy was changed to 7x4 GeV (vertical beam size: 940 nm- >59nm)
To save the short lifetime for LER(Touschek effect)
Crossing angle 83 mrad
To make QCS magnets closer to IP
Separated final quadrupole magnets
Use both of superconducting and permanent magnets
Boundary conditions between accelerator and detector are same as the present
Angle of 41.5 mrad between HER orbit and Belle
To save vertical emittance increase by anti-solenoid fringe fields 37