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Water Sensitivity

Neutrons are extremely sensitive to small amounts of water. To quantify and calibrate this sensitivity we use known thicknesses of water and measure this effect directly. Using a wedge of water formed by incrementally milling steps in a block of aluminum a well known range of steps are formed from 0.050 mm to 2 mm in increments of 0.050 mm. Radiographs of the wedge when wet and dry can be compared to yield the water steps alone. From this the sensitivity of the method can be shown.


Steps machined with 50 micrometer

Steps machined in increments of 0.050 mm.
Images showing scattered density of water
The process of analyzing an image is illustrated here with the water cuvet. The image with wet cuvet is divided pixel by pixel with the image of the dry cuvet leaving only the water image. Finally the negative nautral log of each pixel yields the scattering density of water in 0.050 mm.
Temporal sensitivity in silicon detector
New amorphous silicon detector should have a least a factor of 7 improvement in temporal sensitivity.


Inquiries or comments: David Jacobson

Online: May 2006