DEVICE AND METHOD FOR PRODUCING NEUTRONS

Abstract

The invention relates to a method for producing and/or capturing neutrons, including the following steps: a) exposing nuclei selected among protons, deuterons and/or tritons to an electric field in order to extract said nuclei and to direct said nuclei thus extracted towards a target (20) containing free electrons; b) for example, exposing said nuclei to a spatial and/or temporal gradient of a first magnetic field so as to give a predefined orientation to the magnetic moments of the nuclei; c) either exposing the target to a second magnetic field so as to give a predefined orientation to the magnetic moments of the free electrons of the target; d) or using an electron-donor superparamagnetic material so that the electrons of the free layers of these materials are oriented in preferred directions generated by the orientation of the resulting magnetic moment of the superparamagnetic material; e) for example, in the case of using a superparamagnetic material, not exposing the proton beam and/or the target to the external magnetic fields. A heating device and/or a device for generating magnetic fields may be required in order to activate the superparamagnetic properties of the material.

Claims

1. A method for producing and/or capturing neutrons, comprising the following steps: a) subjecting nuclei chosen from among protons, deuterons and/or tritons to an electrical field in order to extract said nuclei and direct the duly extracted nuclei toward a target (20) containing free electrons, b) subjecting said nuclei to a spatial and/or temporal gradient of a first magnetic field so as to give a predefined orientation to the magnetic moments of the nuclei, and c) subjecting the target to a second magnetic field so as to give a predefined orientation to the magnetic moments of the free electrons of the target.

2. The method as claimed in claim 1, in which the magnetic moments of the nuclei and the magnetic moments of the free electrons are aligned in the same direction or are parallel to the direction of displacement of the nuclei toward the target, being in the same direction or in the opposite direction.

3. (canceled)

4. The method as claimed in claim 1, in which the nuclei are obtained by creating a plasma of hydrogen and/or of deuterium and/or of tritium by application of radiofrequencies or of an electrical discharge.

5. The method as claimed in claim 1, in which said nuclei are subjected to radiofrequencies so as to give a predefined orientation to the magnetic moments of the nuclei.

6. The method as claimed in claim 1, in which the target contains ferromagnetic and/or superparamagnetic materials and the target is subjected to a magnetic field so as to give a predefined orientation to the magnetic moments of the free electrons of the target.

7. The method as claimed in claim 1, in which the target is subjected to radiofrequencies so as to give a predefined orientation to the magnetic moments of the free electrons of the target.

8. The method as claimed in claim 4, in which the radiofrequencies are applied using a radiofrequency generator (8), at a frequency lying between 10 kHz and 50 GHz.

9. The method as claimed in claim 1, in which the electrical field applied is obtained by one or more electrode(s).

10. The method as claimed in claim 1, in which the first magnetic field applied has a spatial gradient lying between 0.001 Tesla/meter and 1000 Tesla/meter over the volume of an enclosure (2) containing said nuclei.

11. The method as claimed in claim 1, in which the free electrons of the target are subjected to a spatial and/or temporal gradient of the second magnetic field, and/or in which the target (20) is metal, and/or in which the target (20) is heated to a temperature which lies between 100 C. and 4000 C.

12. (canceled)

13. (canceled)

14. A device for producing and/or capturing neutrons, comprising: a) an enclosure (2) in which the nuclei chosen from among protons, deuterons and/or tritons can be placed, b) means for applying a spatial and/or temporal gradient of a first magnetic field so as to give a predefined orientation to the magnetic moments of the nuclei present in the enclosure, c) means for applying an electrical field in order to extract said nuclei and direct the duly extracted nuclei toward electrons, and d) means for applying a second magnetic field to said electrons so as to give a predefined orientation to the magnetic moments of the electrons.

15. The device as claimed in claim 14, in which the magnetic moments of the nuclei and the magnetic moments of the free electrons are aligned in the same direction or are parallel to the direction of displacement of the nuclei in the enclosure, being in the same direction or in the opposite direction.

16. (canceled)

17. The device as claimed in claim 14, comprising a radiofrequency generator surrounding the enclosure, making it possible to create a plasma of hydrogen or of deuterium and/or tritium in the enclosure.

18. The device as claimed in claim 14 the means for applying the gradient of the first magnetic field comprising a first electromagnet (10) to produce the first magnetic field.

19. (canceled)

20. The device as claimed in claim 14, the means for applying the electrical field comprising one or more electrode(s) and one or more ground(s), each electrode or pair of electrodes being borne by an electrode holder (24, 23, 26).

21. The device as claimed in claim 20, in which the electrode holder (24, 23, 26) is in the form of a ring, comprising two housings for the electrode and the ground, which can be of identical form.

22. The device as claimed in claim 20, in which the electrode holder (24, 23, 26) comprises transverse orifices, for at least one out of passage for electrical connections, passage for spacers, and/or to balance pressures in the device and for the circulation of the gases.

23. The device as claimed in claim 14, the means for applying the second magnetic field to said electrons comprising a second electromagnet (14) to produce the second magnetic field.

24. The device as claimed in claim 14, comprising a source of electrons making it possible to produce an electron beam.

25. The device as claimed in claim 14, comprising a target (20) containing electrons, intended to receive the nuclei, and/or the target containing ferromagnetic and/or superparamagnetic materials.

26. The device as claimed in claim 14, comprising cooling means and/or energy harvesting means for the production of energy.

Description

DESCRIPTION OF THE FIGURES

[0181] The invention will be better understood on reading the following detailed description, of nonlimiting examples implemented thereof, and on studying the attached drawing, in which:

[0182] FIG. 1 is a schematic and partial perspective view of an example of a neutron production and/or capture device according to the invention,

[0183] FIG. 2 is a view according to the arrow II,

[0184] FIG. 3 is a view in longitudinal cross section according to III-III of the device of FIGS. 1 and 2,

[0185] FIG. 4 is a schematic and partial perspective view of a detail of the device of FIGS. 1 to 3,

[0186] FIG. 5 is a view according to the arrow V,

[0187] FIG. 6 is a view in longitudinal cross section according to VI-VI of the device of FIGS. 4 and 5,

[0188] FIG. 7 is a schematic and partial perspective view of an electrode holder assembly and its electrodes,

[0189] FIG. 7a is a schematic and partial perspective view of the assembly of FIG. 7,

[0190] FIG. 7b is a schematic and partial perspective view of the electrode holder of FIGS. 7 and 7a,

[0191] FIGS. 7c to 7e are views respectively according to the arrows C, D and E of the electrode holder of FIGS. 7, 7a and 7b,

[0192] FIG. 8 is a schematic and partial perspective view of the target surrounded by the associated electrode,

[0193] FIGS. 8a and 8b are views respectively according to the arrows A and B of the cathode of FIG. 8, and

[0194] FIGS. 9 and 10 are views similar to FIG. 3 of variant embodiments.

[0195] FIGS. 1 to 3 schematically illustrate a device 1 according to the invention, comprising an enclosure 2 in which nuclei can be placed at a pressure controlled by a vacuum gauge 5. The enclosure 2 has a generally cylindrical form, and comprises, toward its output end 2c, two lateral branches 2a and 2b, one 2a allowing the passage of the electrical connections 7, and the other 2b the discharging of the gases to the vacuum pump which is not represented. The output end 2c can serve as output for the neutrons produced and/or is input and output for a heat transfer fluid used to cool and/or harvest energy in the heat exchanger or exchangers.

[0196] The nuclei can be chosen from protons (hydrogen nuclei), deuterons (deuterium nuclei) and/or tritons (tritium nuclei) and are obtained for example by introducing into the enclosure a neutral hydrogen or deuterium and/or tritium gas through a gas input 6. The gas can be transformed into plasma by means of a radiofrequency generator 8 comprising an antenna 9 surrounding the enclosure 2.

[0197] The device 1 further comprises means for applying a spatial and/or temporal gradient of a first magnetic field, so as to give a predefined orientation to the magnetic moments of the nuclei present in the enclosure 2. This is, in the example described, an electromagnet 10 with core 10a. The core 10a comprises a channel 10b allowing the input of the gas.

[0198] The device 1 also comprises means for applying an electrical field in order to extract said nuclei and direct the duly extracted nuclei toward electrons. In the example described, these means are an electrode 12, which is an anode in the example described, associated with a ground 13 placed on the other side of an insulating electrode holder 24, as illustrated in more detail in FIGS. 7 and 7a to 7e.

[0199] As can be seen in these figures, the electrode 12 and the ground 13 are identical, to within their polarity, and the electrode holder 24 takes the form of a ring, comprising two housings 40 for the electrode 12 and the ground 13, which are of identical form.

[0200] Furthermore, the electrode holder 24 is pierced with radial orifices 41, two of them in the example described, and which are diametrically opposite. These radial orifices 41 can be used for fixing the electrode holder in the device.

[0201] The electrode holder 24 also comprises transverse orifices 42, 43 and 44. The orifices 42 can be used for the passage of electrical connections 7, on the sides of the enclosure 2, being furthest away from the central axis of the enclosure. These orifices 42 are also of smaller diameter. In the example described, there are six of them, being placed symmetrically around the central axis of the enclosure.

[0202] The transverse orifices 43 can be used for the passage of spacers 30, which allow for the maintaining of the electrodes and for the support of the target. These spacers can be used for the circulation of one or more heat transfer fluid(s) and the extraction of the heat produced in the device. There are four of them in this example, like the spacers 30, and they are placed symmetrically around the central axis of the enclosure.

[0203] Finally, the other transverse orifices 44 can be kept free, being thus able to be used to balance pressures in the device and for the circulation of the gases. There are six of them in the example described being placed symmetrically around the central axis of the enclosure.

[0204] The abovementioned electrons are, in the example described, derived from a beam of electrons extracted from a target 20 held by an insulating electrode holder 23, behind an extraction electrode 25 and a focusing electrode 21. The focusing electrode 21 has a generally tapered form, as illustrated in FIGS. 8a and 8b. The extraction electrode 25 is held on an electrode holder 26, identical to the electrode holder 24 previously described in detail, and the target and the focusing electrode 21 are held on the electrode holder 23, also identical to the electrode holders 24 and 26. The radial orifices 41 can generally be used to fix the target 20 in the electrode holder 23 as illustrated in FIGS. 8, 9 and 10.

[0205] The focusing electrode 21 can be, in the example described, a cathode, brought for example to a potential of 300 V, the extraction electrode 25 then being a ground. In a variant, it could of course be otherwise, the focusing electrode 21 being brought to the ground and the extraction electrode 25 being an anode, for example brought to a potential of approximately +300 V. The extraction electrode 25 can thus be brought to different potentials depending on the mode of use: ground, or positive. The focusing electrode 21, illustrated in more detail in FIG. 8, is a cathode or a ground.

[0206] The electrons from the target 20 are extracted from the target by the action of the extraction electrode 25 which is linked to the ground or brought to a positive potential, and focused toward the nuclei by means of the focusing electrode 21, which is a cathode in this example, or a ground.

[0207] The device could comprise only one electrode out of the extraction electrode and the focusing electrode, without departing from the scope of the present invention.

[0208] Each of the electrodes can be produced in the form of a metal grating, and is borne by a corresponding electrode holder with an outline of ceramic or plastic material, allowing the insulation of the connections from one another.

[0209] The collision takes place in the intermediate space 28 between the electrodes 13 and 25 both linked to the ground, in the case where the electrons are emitted in beam form.

[0210] The device comprises, after the electromagnet with core 10 and electrodes 12 and 13, means for applying a second magnetic field to said electrons so as to give a predefined orientation to the magnetic moments of the electrons. This is in the example described a coreless electromagnet 14. At the core of this electromagnet 14 there are the electrode 13 (ground), the electrode 25 (ground), the electrode 21 (cathode) and the target 20 on its support 23, as illustrated. Thus, the electrons are subjected to the second magnetic field before their collision with the nuclei from the plasma.

[0211] At the output, a beam of neutrons is then obtained, that can be harvested at the end 2c of the enclosure 2.

[0212] In the variant embodiment illustrated in FIG. 9, the device can comprise a specific radiofrequency antenna 50 for modulating the second magnetic field, such that the electrons are subjected to a combination of the second magnetic field of the electromagnet 14 and of the radiofrequency emitted by the antenna 50. This antenna 50 is placed inside the magnet 14, around the enclosure 2.

[0213] In the examples which have just been described, the production of a beam of neutrons is obtained by the capture of the electrons having been extracted from the target 20 by the nuclei of the beam.

[0214] The electrons can, as a variant, be contained in the target, which in this case is intended to receive the nuclei. In this case, the electron/nuclei collision can take place directly on or in the target 20 to generate neutrons by virtue of the alignment of the magnetic moments thereof, and it is possible to obtain a transmutation of the atoms (nuclei) of the target by the capture of the neutrons produced. In this exemplary embodiment of neutron production and capture directly in the target, the electrodes and/or ground 12, 13 and 25 can be used as radiofrequency antennas, in order to improve the rate of alignment of the magnetic moments of the nuclei and/or of the electrons of the target, and thus increase the number of neutrons produced. To this end, they can in the variant illustrated in FIG. 10 be connected to a suitable radiofrequency generator.

[0215] As an example, FIG. 10 illustrates a device which differs from those previously described by the presence of a target 20 without electrode 21, and which is connected to the ground. Furthermore, the electrode 25 is used only for radiofrequency production and is not subjected to a fixed voltage. In a variant embodiment not illustrated, this electrode 25 could even be eliminated.

[0216] The target 20 can have an elongate form, particularly in the direction of the output 2c, so as to facilitate the transmutation of the greatest possible number of atoms. The target 20 can be solid, or fluid, being liquid or including a powder.

[0217] The expression comprising a should be understood to mean comprising at least one.