Challenges for FCC-ee MDI mechanical design BINP Challenges for FCC-ee MDI mechanical design A.Krasnov, E.Levichev, S.Pivovarov, S.Sinyatkin BINP, Novosibirsk Workshop on the Circular Electron-Positron Collider , 24-26th May 2018, Rome Workshop, 24-26 May 2018, Rome

FCC-ee IR new design: motivations BINP There are following problems with the baseline FCC-ee IR design: A cryostat does not fit the detector requirement of 100 mrad lost angle. A space before the cryostat for accelerator components such as beam position monitors, bellows, flanges, etc. can hardly be found. There is no space for remotely controlled flange and hence the procedure of the IR assembling is not clear. Contribution of the compensation solenoid field in the vertical emittance excitation is rather high. Taking above into account we consider an alternative design discussed below. Workshop, 24-26 May 2018, Rome

3D conceptual design Interaction Region. BINP 100 mrad cone IP Anti solenoid. Correction coils IP QC2 Cryostat QC1 Cryostat LumiCal Workshop, 24-26 May 2018, Rome

3D conceptual design Interaction Region. BINP QC2.2 QC2.1 QC1.3 QC1.2 QC1.1 Screening sol. Cryostat “walls” thickness. QC1.1 Outer SS wall 10 mm Remote flange 10 mm vacuumn HOM Absorber Thermal shield 3 mm 10 mm vacuum LumiCal Inner wall 6 mm Correct. sol.(4) In total: ~40…45 mm Anti-sol. Cooling Anti sol. Two bellows BPM Connection Be-Cu Workshop, 24-26 May 2018, Rome Compens. colls

3D views QC2.1 QC1.3 Top view Side view QC2 Cryostat QC1 Cryostat BINP Top view QC1.1 Anti-sol HOM abs Flange Side view BPM LumiCal Transition 30 mm  40 mm Flanges QC2.1 QC1.3 QC2 Cryostat QC1 Cryostat Bellows BPMs BPMs Workshop, 24-26 May 2018, Rome

Conceptual design of beam pipe inside cryogenic magnets Inner stainless steel tube, 0.7 mm thickness with inner Cu coating Gap 0.7 mm with water flow and wire spacers Stainless steel tube 0.7 mm thickness with outer Ag coating Vacuum gap 0.9 mm with Ultem spacers Outer stainless tube, thickness 1 mm, T=4.2K Correction coil If ID=30 mm, the OD is 38 mm Maximum power load on vacuum beam pipe with ID=30mm due to resistivity losses (assuming Cu) and HOM absorption is 50….100 W/m. Therefore the pipe needs an active cooling. Here we are considering multilayer beam pipe with water cooling: Workshop, 24-26 May 2018, Rome

Design of 3 layers vacuum chamber. Ultem ball (0.9 mm) Stainless wireless (0.7 mm) Chamber (1 mm) Chambers (0.7 mm) In half a year we plan to produce a prototype of the 3-layers vacuum tube. We plan to test the cooling water capacity with LHe temperature out of the prototype and the heater (imitating the beam) inside the camber. Workshop, 24-26 May 2018, Rome

Stand for testing the vacuum chamber. Cryocooler SRDK-415 liquid cooling 3 layers Vacuum Chamber Vacuum Water 100W 4.5K Shield 80K Cryostat liquid cooling Now we are preparing a stand for testing the 3 layers vacuum chamber with a length of 1 m. Workshop, 24-26 May 2018, Rome

BINP Remote flange prototype Flange outer dimensions for two beam pipes: Flange 2*radius(2*43)+ distance between beams At s=1385 mm Flange outer size Receiving part 1385*0.03+86 ≈ 128 mm Incoming part with mechanics 128+6≈134 mm Length 64 mm 43 Workshop, 24-26 May 2018, Rome

BINP Remote flange prototype P=100…200 bar. Gasket (Al) Rotatable Ring We designed the prototype of remote flange and after the manufacture we will test the flange connection. Workshop, 24-26 May 2018, Rome

BINP Remote flange prototype Workshop, 24-26 May 2018, Rome

Summary We have started a realistic design of the FCC-ee final focus area which, we believe, satisfies all the requirements both from the detector and accelerator sides. We plan to proceed with development and design of the most critical parts including   (1)    The IR vacuum system, (2)    The remotely connecting flange, (3)    The anti-solenoid with individual correctors, (4)    The first FF quadrupole. Production of the prototypes is highly desirable. Workshop, 24-26 May 2018, Rome

Thanks for your attention Workshop, 24-26 May 2018, Rome