Test of the High-Field \Nb3\Sn Dipole Magnet HD3b.

Authors :: Marchevsky, M.
Caspi, S.
Cheng, D. W.
Dietderich, D. R.
DiMarco, J.
Felice, H.
Ferracin, P.
Godeke, A.
Hafalia, A. R.
Joseph, J.
Lizarazo, J.
Roy, P. K.
Sabbi, G.
Salmi, T.
Turqueti, M.
Wang, X.
Prestemon, S.
Source :: IEEE Transactions on Applied Superconductivity; Jun2014, Vol. 24 Issue 3, p1-6, 6p
Publication Year :: 2014
Abstract: We report test results for the one meter long dipole HD3b, a block-type accelerator quality \Nb3\Sn magnet built at LBNL with operational bore fields in the range of 13–15 T. The magnet is an upgrade of the previously reported HD2 and HD3a versions, with several modifications implemented to improve conductor positioning, reduce cable “hard-way” bending radius, and strengthen electrical insulation between cables and coil parts. The magnet exhibited long training behavior, but showed a good “memory” of the trained state upon thermal cycling. Ramp-rate dependence of the quench current, field quality performance characteristics, and protection heater studies were conducted. Quench propagation velocity and quench locations were determined based on the voltage signals; quench localization was further improved using inductive quench antenna and acoustic emission sensors. Short- and long-term acoustic precursors to quenching were observed. [ABSTRACT FROM PUBLISHER]