Moderated neutron sensor
A moderated neutron detector includes a neutron detector having a first volume. A moderating enclosure is positioned around the neutron detector and encloses a second volume. The second volume is between 2 and 80 times larger than the first volume. A method for increased neutron detection includes the following steps: positioning a neutron detector within a moderating enclosure, wherein the neutron detector has a first volume, wherein the moderating enclosure encloses a second volume, and wherein the second volume is between 2 and 80 times larger than the first volume; increasing a quantity of neutrons impingent upon the neutron detector; and measuring the quantity of neutrons impinging upon the neutron detector.
1. A moderated neutron sensor, comprising:
a single, cylindrically-shaped neutron detector having a diameter dimension, D 1 ; and
a moderating enclosure positioned around the single, cylindrically-shaped neutron detector and enclosing the single, cylindrically-shaped neutron detector therein, the moderating enclosure having a width dimension, D 2 , measured between opposing interior sidewalls having a closest distance therebetween of all sidewalls of the moderating enclosure, wherein a sensitivity of the single, cylindrically-shaped neutron detector is a function of a ratio between D 1 and D 2 , wherein D 2 is equal to or greater than D 1 plus substantially 1.0 inch.
2. The moderated neutron sensor of claim 1 , wherein the single, cylindrically-shaped neutron detector is centrally located within the moderating enclosure.
3. The moderated neutron sensor of claim 1 , wherein a thickness of the moderating enclosure is between 0.5 and 2.0 inches.
4. The moderated neutron sensor of claim 1 , wherein the single, cylindrically-shaped neutron detector further comprises a Helium-3 (He3) detector.
5. A moderated neutron sensor, comprising:
a single, non-cylindrically-shaped neutron detector having an elongated axial length, a first width dimension, D 1 , and a second width dimension, D 2 , wherein D 1 and D 2 are measured perpendicular to the elongated axial length; and
a non-cylindrically-shaped moderating enclosure positioned around the single, non-cylindrically-shaped neutron detector, the non-cylindrically-shaped moderating enclosure has a third width dimension, D 3 , as measured between opposing interior sidewalls of the moderating enclosure, and a fourth width dimension, D 4 , as measured between opposing interior sidewalls of the moderating enclosure, wherein D 3 and D 4 are axially aligned with D 1 and D 2 , respectively, wherein a sensitivity of the single, non-cylindrically-shaped neutron detector is a function of a ratio between at least one of: D 1 and D 3 or D 2 and D 4 , wherein D 3 is equal to or greater than D 1 plus substantially 1.0 inch and D 4 is equal to or greater than D 2 plus substantially 1.0 inch.
6. The moderated neutron sensor of claim 5 , wherein the single, non-cylindrically-shaped neutron detector is centrally located within the non-cylindrically-shaped moderating enclosure.
7. The moderated neutron sensor of claim 5 , wherein a thickness of the non-cylindrically-shaped moderating enclosure is between 0.5 and 2.0 inches.
8. The moderated neutron sensor of claim 5 , wherein the single, non-cylindrically-shaped neutron detector further comprises a Helium-3 (He3) detector.
9. A method for increased sensitivity of neutron detection, comprising the steps of:
positioning a single neutron detector within a moderating enclosure, whereby a minimum spaced distance is formed between an exterior surface of the single neutron detector and an interior surface of the moderating enclosure at a closest distance therebetween, wherein a difference between a depth of the single neutron detector and a depth of the moderating enclosure is larger than a difference between a length of the single neutron detector and a length of the moderating enclosure; and
detecting a quantity of neutrons with the single neutron detector, wherein a sensitivity level of the single neutron detector correlates with a radial volume formed within the minimum spaced distance between the exterior surface of the single neutron detector and the interior surface of the moderating enclosure.
10. The method of claim 9 , wherein the single neutron detector is centrally located within the moderating enclosure.
11. The method of claim 9 , wherein the radial volume is between 2 and 20 times larger than a volume of the single neutron detector.
12. The method of claim 9 , wherein the radial volume is between 5 and 10 times larger than a volume of the single neutron detector.
13. The method of claim 9 , wherein a thickness of the moderating enclosure is between 0.5 and 2.0 inches.
14. The method of claim 9 , wherein the sensitivity level of the single neutron detector is increased over a neutron detector having a close fit moderator by a factor greater than 1.3.
15. The method of claim 9 , wherein the sensitivity level of the single neutron detector is increased over a neutron detector having a close fit moderator by a factor greater than 1.5.
16. The method of claim 9 , wherein the single neutron detector further comprises a Helium-3 (He3) detector.