1. `Final’ Detector Design
Harry Nelson
Meeting
April 3, 2008
University of California, Santa Barbara

2. n Detector Meeting - Harry Nelson
Signal from γ’s from Neutron Capture in 0.2% GdCl3 From Super-K (courtesy of Mark Vagins UCI)
About 22 pe
(5 pe/MeV)
Acceptance… 40%
U/Th Chain
April 3, 2008
n Detector Meeting - Harry Nelson

3. n Detector Meeting - Harry Nelson
April 3, 2008
n Detector Meeting - Harry Nelson

4. A `Box of Rain’ – Calculate 5 pe/MeV
Two Super-K Tubes – need low level coincidence
60 cm (24”)
White Diffusive
Reflector
Water + GdCl3
200 cm (79”)
April 3, 2008
n Detector Meeting - Harry Nelson

5. Formulas for Collection Efficiency
April 3, 2008
n Detector Meeting - Harry Nelson

6. Required Diffuse Reflectivity
200 x 100 x 60 cm3 → 2 Super-K PMTs → φ=3.8%
for ε >40%, need R>94% (8.4 bounces)
Next Prototype: Cube
40 x 40 x 40 cm3 → 2 8” SK Veto PMTs → φ=5.9%
for ε >40%, need R>90%,
(5 bounces)
Take this to Soudan…
April 3, 2008
n Detector Meeting - Harry Nelson

7. n Detector Meeting - Harry Nelson
Schedule….
Proceed with 40 x 40 x 40 detector – 2 months (?)
Susanne has scoped out halon manufacture
Give up on scintillator (95% confident)
Major acquisitions split between FY2008/2009
April 3, 2008
n Detector Meeting - Harry Nelson