IR Beam Transport Status C. Hutton, F. Lin, V. Morozov, R. Rajput-Ghoshal, G. Wei, & M. Wiseman March 1, 2018

Outline Overall area view Magnet design status Area and cryostat designs Remaining high level plan 3/1/2018

IR Area The design thus far has been considered six distinct areas Detector Solenoid ( 4 m) SB1 dipole (1.5 m) SB2 dipole (~4.6 m) Ion entrant side cryostat (~8.7 m) Electron entrant cryostat between the SB1 and Detector Solenoid (~2.6 m) Ion down beam cryostat between the two dipoles (~11.1 m) Our work so far has focused on the three beam transport areas Paul Brindza has done some preliminary work on the detector solenoid, SB1, and SB2 magnets 1 2 5 6 3 4 ~32 m i e 3/1/2018

Detector Solenoid and IR Vacuum Chamber The detector solenoid as modeled 4m long, inner radius 150 cm and 10 cm thick Don’t know if this matches the P. Brindza work 3T field used in beam transport studies The vacuum chamber geometry defined by Charles Hide “Interaction Region Optics and Beam Stay Clear for Ion Injection: Impact on Central Vacuum Pipe Design” Dec. 13, 2017 This is being used in impedance, vacuum, and detector studies 160 cm 240 cm e i Interaction point 3/1/2018

SB1 & SB2 Dipole Models SB2 SB1 (CF Ion) SB1 – P. Brindza 6/23/17 P. Brindza 9/8/17 SB1 and SB2 based on the above designs from P. Brindza Cryostat w warm bore (blue) & yoke steel (grey) Other designs are being considered for the SB1 SB1 (CF Ion) SB2

Magnet Design Status 3/1/2018

Magnet Design Status 3/1/2018

Magnet-Magnet Interaction Currently looking at the interaction between two closest magnets QFFDS2 and QFFB1_US Looking at the following parameters Stored Energy of the magnet Field from one magnet on the axis of the other magnet Field from one magnet on the good field radius of the other magnet Effect of one magnet on the gradient of the other magnet Effect on higher order multipoles Shielding IPUSCORR2 QFFDS1 IPUSCORR1 QFFB1_US QFFDS2 QFFDS3 e i 3/1/2018

Magnet-Magnet Interaction QFFB1_US QFFDS2 QFFB1_US and QFFDS2 Simulated together Three Simulations: Simulation 1: Both Magnets at Full current Simulation 2: QFFDS2 at 0A and QFFB1_US at full current Simulation 3: QFFB1_US at 0A and QFFDS2 at full current Stored Energy Simulation 1: 83828 J Simulation 2: 70984 J Simulation 3: 12405 J Additional stored energy due to mutual inductance is approximately 438 J Field at the Axis 3/1/2018

Magnet-Magnet Interaction Three Simulations: Simulation 1: Both Magnets at Full current Simulation 2: QFFDS2 at 0A and QFFB1_US at full current Simulation 3: QFFB1_US at 0A and QFFDS2 at full current Effect on Gradient QFFB1_US QFFDS2 3/1/2018

Magnet-Magnet Interaction- Higher order Multipoles 3/1/2018

Magnet-Magnet Interaction- Higher order Multipoles 3/1/2018

Magnet-Magnet Interaction Shielding Iron (passive shield) Coil (active shield) Results from 10 mm thick passive shields Parallel magnet configuration QFFB1_US QFFDS2 With Shielding With Shielding 3/1/2018

Magnet-Magnet Interaction Next step Waiting for simulation to complete with 10 mm iron shield with QFFB1_US inclined Change iron shield thickness based on the 10 mm thick shield results Simulate an active shield Study effect of magnet on the beam line of other magnets (some of the magnets are even closer to the beam line of other ring) 3/1/2018

Quad with nested skew quad Ion Supply Side Design efforts to date have focused on the ‘Z’ spacing of the magnets As a rule of thumb we have tried to reserve 10 cm on each magnet end for field optimization, coil clamps etc. Just starting to look at the radial design and magnet fringe fields Three identical quads in electron line with nested skew quads No multipole correctors planned Three quads in ion line Still to add nested skew quads and multipole correctors 1.2 m solenoid in each line (same design) Two horizontal/vertical correctors in ion line near IP Quad with nested skew quad IPUSCORR2 QFFDS1 IPUSCORR1 QFFB1_US QFFDS2 QFFB2_US EL SOL ANTI_DS QFFDS3 AASOLEUS QFFB3_US 1st dipole in Compton chicane e i 3/1/2018

Ion Supply Side Currently looking at stray fields in two ‘worst case’ locations Between QFFDS1 and QFFB1_US quads Plan to look near QFFDS1 and other areas as time permits Requirements, spacing and size of the of ion correctors still being looked at Common magnet design for now Do not have the desired 10 cm of space on each end yet IPSCORR2 is close to the electron vacuum line (~1.5cm) and the detector solenoid (~16 cm along beam line) IPUSCORR2 QFFDS1 IPUSCORR1 QFFB1_US QFFDS2 QFFDS3 i e 3/1/2018

Ion Supply Side All magnets based on cold bore design Required for the ion beam quads, optional for the electron beam ones One cryostat for all magnets ~ 8.7 m long on Ion beam line (~0.026 m beamline contraction) Little room between magnets for smaller cryostats 18 + (?) magnets - 6 quads, 6 skew quads, 2 X&Y correctors, 2 anti-solenoids, (?) multipole correctors, & (?) shielding coils Super KEKB IR cryostats have 25 and 30 magnets Cryogenic connections and leads (location TBD) ~8.7m 3/1/2018

Cryostat ends Additional considerations at the beam line ends of each cryostat Example shown on next slide Interconnects (space between cryostats and other components) Reserve 10 to 20(?) cm for bellows, vacuum pumping, assembly etc. Warm to cold beam tube transitions Reserve 30 cm for cold bore designs If we include a bellows this could be less Since a bellows is also desired in the interconnects for installation, tried to avoid a bellows here to minimize the number of RF shielded bellows Could be reduced to 10 cm for warm bore designs With the current beam transport design some of this will end up inside the detector solenoid and SB1 dipole ~8.7m 3/1/2018

Warm to Cold Transitions and Bellows 10 cm 4 cm 30 cm ~34 cm inside detector solenoid Vacuum vessel end wall RF shielded bellows Vacuum vessel bellows 10 cm for coil shaping, collar, etc. 30 cm warm to cold transition to flange Trying to keep bellows out of the beam tube for now Thin beam tube to minimize conduction, ~0.030” Includes 4 cm for helium vessel, thermal shield, MLI, vacuum space 10 to 20 cm for shielded bellows, vacuum pumping, etc. Vacuum vessel and bellows will extend inside the detector solenoid space Cartoon shown on one vacuum tube only Similar requirements on the ion down beam side around the detector solenoid and SB1 dipole e ion corrector Quad w skew quad 3/1/2018

Ion Down Beam #1 Tried to keep all magnets outside of the SB1 dipole – Self imposed constraint Common electron beam quad with nested skew quad Still to add a H/V corrector on ion line Design specification in progress Large bore SB1 dipole shown QFFUS1 IPDSCORR1 ? QFFUS2 SB1 e i 3/1/2018

Synchrotron radiation intercept Ion Down Beam #1 Intercept needed for synchrotron radiation in the electron line Placeholder shown as a ‘waist’ in the vacuum tube Located ~33 cm from QSFFUS1, so within the space needed for a warm to cold transition May be able to move this when we look at the synchrotron radiation Could push us to change to warm bore design in this area QFFUS1 e i Synchrotron radiation intercept ~33 cm ~53 cm ~4 cm 3/1/2018

Cryogenic connections and magnet leads Ion Down Beam #1 One vacuum vessel between detector solenoid and SB1 ~2.6 m long on e beam line Both beam lines may need to be included in the cryostat 6 + (?) magnets - 2 quads, 2 skew quads, X&Y corrector, & (?) shielding coils Most in e beam line Vacuum vessel warm to cold beam tubes will extend into the SB1 ~23 cm between QFFUS02 and SB1 Warm bore magnet designs might avoid this Could consider combining with SB1 Area is closely coupled to SB1 and detector designs Cryogenic connections and magnet leads ~2.6 m 3/1/2018

Ion Down Beam #2 Tried to keep all magnets outside of the SB1 dipole – Self imposed constraint Common electron beam quad with nested skew quad (QFFUS3) Solenoid in electron line same design as on ion supply side (EL SOL ANTI_DS) Large bore solenoid in ion beam line (AASOLEDS) Three large bore, high strength quads in ion line (QFFB1, 2, 3) Working on multipole correctors Four separate skew quads in ion line – final locations TBD (QFFDS01S, 02S, 22S, 03S) Space is tight for the first one and may need more room between QFFB3 and the solenoid Working on a corrector design located near the SB1 dipole in ion line (IPDSCORR2) QFFUS3 IPDSCORR2 ? QFFB1 EL SOL ANTI_US QFFB2 QFFDS02S QFFDS01S QFFDS22S QFFB3 QFFDS03S AASOLEDS Warm Quad (not all shown) SB1 SB2 e i 3/1/2018

Ion Down Beam #2 Area near the SB1 is crowded ~8 cm between QFFUS3 and SB1 As shown, ~2 cm to QFFDS01S and SB1 - final location TBD IPDSCORR2 corrector design in progress Closely coupled to the SB1 design Still need to consider detector requirements QFFUS3 IPDSCORR2 ? QFFB1 EL SOL ANTI_US QFFB2 QFFDS02S QFFDS01S SB1 3/1/2018

Probably one vacuum vessel between the dipoles Ion Down Beam #2 Probably one vacuum vessel between the dipoles ~11.1 m long along the ion line (~0.033 m cool down change in length) Both beam lines included (at least near SB1) ~13 + magnets - 4 quads, 5 skew quads, X&Y corrector, 2 anti-solenoids, (?) Multipole correctors, & (?) shielding coils Vacuum vessel warm to cold beam tubes will extend into the SB1 ~11.1 m Cryogenic connections and leads (location TBD) 3/1/2018

Near Term Plan Incorporate detector requirements as needed for the pCDR Look at stray field mitigation in worst locations Incorporate the multipole corrector designs in at least one ion quad Magnet and cryostat radial design for space in the worst location Investigate the magnet stress in worst large bore ion quad Generate the preliminary corrector designs for the ion beam line As time permits, optimize the magnet ends, investigate forces, multipoles, etc. in other magnets Support vacuum, impedance, detector background studies, etc 3/1/2018

Back Up Slides

9/7/17 Electron Beam Entrant Quads QFFB2e_US QFFB3e_US EL SOL ANTI_US e QFFB1e_US I IPDSCORR1 SB1 IPDSCORR2

10/27/17 Electron Beam Entrant Quads QFFUS1 QFFUS3 QFFUS2 IPDSCORR1 SB1