Superconducting Toroidal Spectrometer

TREK setup

Superconducting toroidal magnet

toroidal Magnet

E246 experiment at KEK-PS

KEK-PS E246 detector system

Main parameters of the Super-conducting Toroidal Spectrometer

Type of the magnet Toroidal magnet with iron cores
Number of gaps and coils 12
Field type Superposition of dipolar and toroidal fields
Maximum central field strangth 1.8 T
Analysis momentum range ∼ 300 MeV/c
Source position Center of the magnet
Solid angle acceptance ∼ 10 %
Magnet cooling Forced two-phase He flow

Detector configuration

Kaon target Scinitillating fiber bundle (60 - 100 mm in diameter)
Tracker MWPCs and GEMs at entrance and exitt of the magnet gaps
Typical momentum resolution 1.0 % at 250 MeV/c
Particle ID TOF, aerogel Cherenkov counter and Lead glass counter
EM calorimeter CsI(Tl) barrel with 768 modules with muon holes
Muon polarimeter Measurement of transverse and longitudinal polarization

Technical papers

Total detector system J.A. Macdonald et al. Nucl. Instr. Method, A506 (2003) 60
CsI(Tl) calorimeter D.V. Dementyev et al. Nucl. Instr. Method, A379 (1996) 499
CsI(Tl) calorimeter Y. Kudenko et al. Nucl. Instr. Method, A411 (1998) 437
CsI(Tl) calorimeter D.V. Dementyev at al. Nucl. Instr. Method, A440 (2000) 151
Target ring counter A.P. Ivashkin et al. Nucl. Instr. Method, A394 (1997) 321
Magnet field T. Ikeda et al. Nucl. Instr. Method, A401 (1997) 243