Neutron Source for Neutron Capture Therapy

1 . A therapy apparatus for producing thermal neutrons at a tumor site in a patient comprising:

a plurality of fast neutron sources surrounding a moderator;

a fast neutron reflecting media around the fast neutron sources;

a gamma-ray and neutron shielding media surrounding the fast neutron reflecting media; and

a patient chamber positioned inside the moderator;

wherein the fast neutron sources are positioned around the moderator to maximize and direct the neutron flux to said tumor site.

2 . The therapy apparatus according to claim 1 wherein the moderator maximizes the neutron flux, delivers a uniform dose and a high and uniform therapeutic ratio across the cancer site.

3 . The therapy apparatus according to claim 1 wherein the patient chamber's position and material of the moderator are selected to produce the maximum, uniform thermal neutron flux and uniform therapeutic ratio at the said tumor sites.

4 . The therapy apparatus according to claim 1 wherein the fast neutron sources are positioned at a fixed radius and equally spaced in a circle around the moderator.

5 . The therapy apparatus according to claim 1 wherein the fast neutron sources are moveable and positioned to maximize the neutron flux at the cancer site.

6 . The therapy apparatus according to claim 1 wherein said fast neutron sources are moveable and are positioned to maximize the neutron flux at the cancer site, to deliver a uniform dose across the cancer site greater than 1 Gy per session with a 10% or less variation, and to deliver a therapeutic ratio at the cancer site greater than 2, and with a uniformity across the cancer site of 10% or less variation.

7 . A therapy apparatus according to claim 1 wherein said moderator is cylindrical in shape.

8 . A therapy apparatus according to claim 1 wherein the moderator is hemispherical in shape.

9 . The therapy apparatus according to claim 1 wherein the moderator is ellipsoidal in shape.

10 . A therapy apparatus for producing thermal neutrons at tumor sites in a patient comprising:

a plurality of fast neutron sources;

a moderator disposed inside the fast neutron sources;

a patient chamber disposed inside and center of the moderator; and,

a neutron reflector and shielding apparatus disposed around the fast neutron generating target.

11 . A therapy apparatus for producing thermal neutrons at a tumor site in a patient comprising:

a plurality of ion sources;

a cylindrical electron shield disposed coaxially inside the said ion sources;

a cylindrical fast-neutron generating target disposed coaxially inside said electron shield that includes an ion entrance aperture disposed to have ions emitted from the ion source impact a fast-neutron-generating target;

a cylindrical moderator disposed coaxially inside the said cylindrical fast-neutron-generating target;

a patient chamber disposed coaxially inside said cylindrical moderator; and

a neutron reflection and shielding means disposed coaxially around said ion beam sources.