Speaker
Description
The Interaction Regions (IR) for the FCC-ee collider as envisioned by the CERN FCC Feasibility Study requires a variety of superconducting correction coils that must be integrated with the main IR focusing quadrupoles. The design of corrector magnets takes advantage of BNL’s Direct Wind coil technology to essentially print multiple nested corrector layers, with small diameter superconductor wire, on a common support tube. As with the main quadrupole coils, because there is no magnetic yoke material between the side-by-side coils, these corrector coils must include a deliberate, longitudinally varying, admixture of field harmonics to self-consistently compensate for field crosstalk between neighboring coils. This talk will cover the design of correctors for FCC-ee IR using multi-functional canted cosine theta direct wind magnets with longitudinal varying harmonics. Electromagnetic design for corrector assembly for final focusing quadrupoles will be discussed. BNL is working on developing a demonstrator multi-functional canted cosine theta direct wind magnet with longitudinal varying harmonics for annulling cross talk in vicinity of an existing direct wind quadrupole magnet. Design status of this magnet along with preliminary electromagnetic design of screening solenoid magnet will also be discussed in the talk. Talk will also touch base on recent nano-meter level magnetic field vibration measurements carried out jointly by BNL and KEK. Such measurements will be crucial for nano-meter beam colliders.
