Status on Work for Splitter FS and Dilution System FS Christoph Hessler TT20 for BDF Meeting 06/03/2017

Assumed Beam Parameters Value Energy (GeV) 400 Norm. horizontal emittance (μm) 14.9 Norm. vertical emittance (μm) 14.2 Phys. horizontal emittance (m) 3.503619e-08 Phys. vertical emittance (m) 3.335715e-08 Beta_x (m) 31.468311 Beta_y (m) 137.60468 Alpha_x -1.533736 Alpha_y -3.738247 Mu_x 0.47825 Mu_y 0.33557 D_x -0.2291 DP_x 0.01359 D_y 0.289 DP_y 0.00348 From tracking simulations From official optics 06 March 2017 C. Hessler

Present Optics for TT20 2016 optics for TT20 (T2) as found on /afs/cern.ch/eng/ps/cps/TransLines/TT20/2016 Beta function for other targets even higher. → Are these optics really used in practice? 06 March 2017 C. Hessler

Preliminary Beam Line Design (I) Preliminary beam line design by Brennan Goddard and Matthew Fraser: 17 new MBBs, 5 new quadrupoles Dispersion suppression scheme 06 March 2017 C. Hessler

Beam Optics (I) Beam matched to 10 mm sigma at the target Dispersion well suppressed 06 March 2017 C. Hessler

Aperture (I) But: Partially only 2 sigma aperture! 06 March 2017 C. Hessler

Preliminary Beam Line Design (II) 5 new MBBs, 18 new MBNs, 6 new quadrupoles. Beam from SPS matched to the FODO structure of the beam line. Beam matched to the FODO structure of the new part of the line. Beam not yet matched to the target Dispersion not yet suppressed at target. Work in progress 06 March 2017 C. Hessler

Aperture (II) Now there are some problems in the existing part of the line, but not as severe. More optimization needed. 06 March 2017 C. Hessler

Aperture studies for splitting magnet Based on Matthew’s preliminary beam line design Beam envelope (6 sigma) and the position of the beam deflected by 8.2 mrad in total calculated in the enlarged MSSB. Error distributions for quadrupole alignment errors, main dipole field and tilt errors and injection errors added and beam coordinates for 1000 random values of these error distributions calculated. In the attached pictures you can see the cross section at the start of the 1st splitter magnet, after each splitter magnet and after BTV.211743 . Each trajectory shows a red spot (not really visible) surrounded by an ellipse defining the 6 sigma beam radius. The green spot and ellipse is the non-deflected beam. The beam direction is out of the plane. By averaging over all trajectories I got the following values for the transverse position of the beam centre: 06 March 2017 C. Hessler

Aperture studies for splitting magnet <x>= 0.08 mm <x>= 6.51 mm <x>= 28.11 mm <x>= 64.88 mm <x>= 83.46 mm 06 March 2017 C. Hessler

Next Steps Survey matching to the good target position → Where is it? CCS coordinates? Using good beam parameters. Match beam to the target Dispersion suppression. Get aperture problem fixed. Add dilution kickers. → Which magnet type? Proposal MPLH/MPLV. 06 March 2017 C. Hessler