1. Upgrade magnets and power supplies
Large Area RICH JLab/CLAS12
Measure polarized ep, ed Deep-Inelastic-Scattering at high luminosity (~ 1035 cm-2 s-1)
Hadron structure in 3D !!!!!
Hall B
Central
Detector
Forward Detector
Beam current mA
Beam polarization 85 %
CHL-2
CEBAF 12 GeV
upgrade in 2013
Upgrade magnets and power supplies
Basic Requirements
Hadron ID from 3 to 8 GeV/c
Pion rejection > 100
Additional system requirements of the PID detectors:
non invasive: small and uniform material budget
Minimize photon detector surface (minimize cost)
operate in large background environment
(GeV/c)
K/ ratio ~
M. Contalbrigo, E. Cisbani, P .Rossi
RICH 2010, 6-7 May, Cassis 1 1

2. Mean pk separation (5-8 GeV)
Preliminary design of the large area RICH
B ~ 40 G
Projective geometry: 6 radial sectors
~ 1 m gap
B ~ 500 G
RHIC
TOROID
RHIC
Mean pk separation (5-8 GeV)
Mean p.e. number (5-8 GeV)
Radiator: Aerogel
 3 cm thickness
 refraction index
K-p separation > 4s at 8 GeV with
smaller than 1 cm detector pixel
Optmized geometry
Photon detector options with light
concentrator (a` la COMPASS)
 MAPMT’s
 SiPM with narrow time window
to suppress background
M. Contalbrigo, E. Cisbani, P .Rossi
RICH 2010, 6-7 May, Cassis 2