TK, Oct.06, 2004
Possible 2km Detector configuration
with 8inch PMTs
• Old design for the water Cherenkov
detector (20inch PMTs)
• New design for the water Cherenkov
detector (8inch PMTs)
• Extra space for FGD
Old design for the water Cherenkov detector
(20inch PMTs)
14.0m
2m
8m
φ4m
Φ8.0m
Φ9.3m
2m
2m
16.0m
4m
New design for the water
Cherenkov detector
Criteria
• The fiducial mass should not change (100tons)
• The diameter of the TANK should not change (9.3m)
• The definition for the fiducial volume should not change:
2m
2m
4m
beam
2m
20 and 8 inch PMTs
25cm
Tank wall
New design (8 inch PMTs)
2m
Φ4.5m
Fid. Mass=
100tons
(same as
before)
Φ8.5m
Φ9.3m
(same as before)
2m
4m
6.3m
2m
12.3m
13.8m
(2.2m shorter)
Number of PMTs (new tank)
•
•
•
•
Assume: 40% photo-coverage (i.e., every 28.7cm)
Barrel: 42×93=3906
Top and bottom: 2×877=1754
Total: 5660
Extra space for FGD
New water
cherenkov
detector
8.7m (3.0+3.0+0.5+2.2)
For FGD
(such as LAr)
(Stairways and
others need to be
reconsidered.)