BI.BSW Chicane Magnets review

BI.BSW Chicane Magnets review D. Aguglia, B. Balhan, J. Borburgh, C. Bracco, B. Goddard, D. Nisbet

Contents Bump closure Influence from the main dipoles Multi turn (>2) variants feasibility Chicane powering Review follow up on PSB 160 MeV H- injection

Bump closure simulation 1/3 (action 6,7,8) • 4 BSW’s (1 ring) modelled in single FE model (Vector Fields). • No cross talk between magnets observed. • Bump closure simulated at nominal current: bump is closed within the accuracy of the model (mesh size ~2mm). Complete field map available. Review follow up on PSB 160 MeV H- injection

Bump closure simulation 2/3 Not to scale Review follow up on PSB 160 MeV H- injection

Bumpclosure 3/3required/assumedtolerances • The non-closure amplitude is estimated assuming 66 mrad deflection and 6 m average H beta function, with uncorrelated errors • *Note that for the vertical orbit non-closure, the roll angle tolerance of the dipole magnets is about 1 mrad (much more sensitive) • Tolerances are typically 1e-3, and 1 mrad alignment, except yaw which can be 20-30 mrad • Tracking accuracy of individual supplies will need to be better than 1e-3 Review follow up on PSB 160 MeV H- injection

Influence of the main dipoles (action 8, 22) • A very large model with a ¼ of BHZ and BS1(ring 3 and 4) was created in Vector Fields. • Field has been analysed to study effect on BS1 at injection (160 MeV). • Model was made available to the MSC group to assess the impact of the BSW’s on the BHZ. Review follow up on PSB 160 MeV H- injection

Influence of BHZ on BS1 at injection Small reduction of ∫B.dl of BSW (~3‰) Very limited effect on field homogeneity Effect on BS4 still to be quantified Complete field map available Review follow up on PSB 160 MeV H- injection

Multi-turn BSW variants (action 9) • 8 turn version feasible for window frame variants (BSW2,3,and4). • Only 2 or possibly 4 turn variant possible for septum (BSW1). Depending on leak field requirements (still to be defined and calculated). Review follow up on PSB 160 MeV H- injection

Chicane powering (action 5) 1/3 2 different nominal currents (BSW1 and BSW2-4), with separate power supplies for each. Current setting individually adjustable for each magnet (±5% w.r.t nominal setting). Transformers in tunnel from BSW1’s (4 in total) in case 2 turn magnets. Transformers might be put farther from injection area in case of 4 turn magnets. No transformers needed in tunnel for 8-turn BSW’s. Review follow up on PSB 160 MeV H- injection

Chicane powering (action 5) 2/3 • Powering solution 1 • BSW1 at 13.5kA individual (4x), BSW2,3&4 3.4 kA individual (12x). • Powering solution 2 • BSW1 at 13.5kA individual (4x), BSW2&3 3.4 kA in series (4x), BSW4 3.4 kA individual (4x). • Powering solution 3 • BSW1 power supplies 13.5 kA (4 x), BSW2-4 power supplies 3.4 kA (4 x), Trim power supplies for BSW4 and BSW3 (200A, 8 x). Review follow up on PSB 160 MeV H- injection

Chicane powering (action 5) 3/3 Solution 1 Solution 2 Solution 3 • Powering solution 1: full optics control, Power conv. low development risk, the most voluminous. • Powering solution 2: reduced optics control, Power conv. low development risk, less voluminous w.r.t. solution 1. • Powering solution 3: full optics control, Power conv. increased development risk, least voluminous solution, more complex controls, NEEDS MORE DEVELOPMENT EFFORTS. Possible circuit diagrams Review follow up on PSB 160 MeV H- injection

BI.BSW Chicane Magnets review