A moderated neutron sensor, comprising: a single, sheet form neutron detector having a first volume; and a moderating enclosure surrounding and enclosing the single, sheet form neutron detector, wherein the moderating enclosure encloses a second volume, the second volume determined from an interior width, interior depth, and interior length of the moderating enclosure, characterized in that: a difference in a depth direction between the first volume and the second volume is larger than a difference in length between the first volume and the second volume, wherein the depth direction is measured orthogonally across an end face of the single, sheet form neutron detector, wherein a spaced distance, as measured between an exterior surface of the single, sheet form neutron detector and an interior surface of the moderating enclosure, is larger in the depth direction than a length direction, and wherein the spaced distance is at least 1.27 cm (0.5 inch), wherein a sensitivity of the single, sheet form neutron detector is a function of moderating enclosure depth measurement relative to the single, sheet form neutron detector, wherein the sensitivity of the single, sheet form neutron detector increases as the moderating enclosure depth measurement increases. a single, sheet form neutron detector having a first volume; and a moderating enclosure surrounding and enclosing the single, sheet form neutron detector, wherein the moderating enclosure encloses a second volume, the second volume determined from an interior width, interior depth, and interior length of the moderating enclosure, characterized in that: a difference in a depth direction between the first volume and the second volume is larger than a difference in length between the first volume and the second volume, wherein the depth direction is measured orthogonally across an end face of the single, sheet form neutron detector, wherein a spaced distance, as measured between an exterior surface of the single, sheet form neutron detector and an interior surface of the moderating enclosure, is larger in the depth direction than a length direction, and wherein the spaced distance is at least 1.27 cm (0.5 inch), wherein a sensitivity of the single, sheet form neutron detector is a function of moderating enclosure depth measurement relative to the single, sheet form neutron detector, wherein the sensitivity of the single, sheet form neutron detector increases as the moderating enclosure depth measurement increases. a difference in a depth direction between the first volume and the second volume is larger than a difference in length between the first volume and the second volume, wherein the depth direction is measured orthogonally across an end face of the single, sheet form neutron detector, wherein a spaced distance, as measured between an exterior surface of the single, sheet form neutron detector and an interior surface of the moderating enclosure, is larger in the depth direction than a length direction, and wherein the spaced distance is at least 1.27 cm (0.5 inch), wherein a sensitivity of the single, sheet form neutron detector is a function of moderating enclosure depth measurement relative to the single, sheet form neutron detector, wherein the sensitivity of the single, sheet form neutron detector increases as the moderating enclosure depth measurement increases.