1. K.B. Beard1#, S.A. Bogacz2, V.S. Morozov2, Y.R. Roblin2[
SIMULATIONS OF A MUON LINAC FOR A NEUTRINO FACTORY* *
K.B. Beard1#, S.A. Bogacz2, V.S. Morozov2, Y.R. Roblin2
1Muons Inc, 2Jefferson Lab
Muons, Inc.
146 m
ABSTRACT
The Neutrino Factory baseline design1 involves a complex chain of accelerators including a single-pass linac, two recirculating linacs and an FFAG. The first linac follows the capture and bunching section and accelerates the muon of both signs from about 244 to 900 MeV2,3. It must accept a high emittance beam about 30 cm wide with a 10% energy spread.4 This linac uses counterwound, shielded superconducting solenoids and 201 MHz superconducting cavities. Simulations have been carried out using several codes including Zgoubi, OptiM5, GPT6, Elegant7 and G4beamline8, both to determine the optics and to estimate the radiation loads on the elements due to beam loss and muon decay. 1
Beta functions and matching calculated using OptiM5,9.
146 m 3m 5m 8m
G4beamline8 model of whole neutrino factory linac showing lower, middle, and upper cryomodules.
OptiM
G4beamline (initial phasing)
G4beamline (rephased)
t[nS]
KE[MeV]
Details of the G4beamline v2.08 upper cryomodule.
Bunches sampled along the linac (centroids shifted for clarity).
CONCLUSIONS AND FUTURE PLANS
Generally, the GPT, OptiM, elegant, and G4beamline (with some RF phase adjustments) simulations are in good agreement. Work is ongoing to greatly improve G4beamline’s RF phasing ability, and when that is complete, the transverse matching between the sections will be revisited. After that, extensive simulations will be run to calculate the heat and radiation loads on all the components of the linac. While some collective effects have already been addressed9, G4beamline has recently added a space charge calculation.10
~ oncrest
~ 1 synch period
t[nS]
Pz[MeV/c]
References
A bunch at the end of the linac with and without induced synchrotron motion.
[1] Interim Design Report, IDS-NF 020,
[2] C. Bontoiu et al., IPAC'10, Kyoto, Japan, May 2010, pp
[3] J. S. Berg et al., Phys. Rev. ST Accel. Beams, 9:011001,2006.
[4] S.A. Bogacz. Nucl. Phys. B Proc. Suppl., 149:309–312, 2005
[5] V. Lebedev, OptiM -
[6] B. van der Geer and M. J. de Loos. General Particle Tracer -
[7] M. Borland, Elegant -
[8] T.J.Roberts, G4beamline -
[9] J. Pozimski et al., IPAC'10, Kyoto, Japan, May 2010, pp
[10] T.J. Roberts et al., “Particle Tracking in Matter Dominated Beam Lines”, these proceedings
Acknowledgements
*Supported in part by US DOE STTR Grant DE-FG02-08ER86351