Electric discharge device for producing interactions between nuclei

Philo T. Farnsworth, Fort Wayne, Indiana, assignor to International Telephone and Telegraph Corporation. Filed January 11, 1962, Serial No. 165,639. 26 Claims. (Cl. 176-1). Patented June 28, 1966.

This application is a continuation-in-part of Philo T. Farnsworth application Serial No. 583,291, filed May 5, 1956, now abandoned, and application Serial No. 63,411, filed October 18, 1960, now abandoned.

The present invention relates to a space charge device, and more particularly to a space charge device having utility for producing nuclear reactions.

In producing nuclear reactions, this invention utilizes unique apparatus for creating an electric field in space within which charged nuclear particles are oscillated at a sufficient velocity that resulting collisions of particles produces nuclear reactions. One such apparatus is an electron tube structure having concentrically arranged cathode and anode elements, the anode element being electron permeable and supported within the cathode element. Electrons emitted by the cathode permeate the anode element and approach the center thereof at which point they exert electrical repulsion forces on each other. As a consequence, the velocities of the electrons as they approach the anode center decrease, giving rise to a space charge buildup which correspondingly reduces the space potential with respect to the anode, and very near the exact center of the anode the electrons, for all practical purposes, nearly stop, thereby producing a small virtual cathode.

Atomic particles in the anodic space are ionized by collision with the electrons, the ion density being greatest at the anodic center on virtual cathode. Ions formed inside the anode are oscillated at nuclear-reacting velocities through the anodic center by the forces of the anodic space potential, so that nuclear collisions result which produce nuclear reactions. The magnitude of energy liberation and character of reactant products of such reactions will depend upon the nuclear compositions of the atomic particles used, the kinetic energies involved, and the other factors pertinent to nuclear reactions, the particular parameters and constituents used depending upon the type of reaction and energies desired.

It is therefore an object of this invention to provide a virtual cathode in free space which may be utilized in conjunction with means for ionizing atomic particles.

It is another object to provide a device for oscillating projectile particles through a region of free space in sufficient numbers to cause collisions thereof which generate nuclear reactions.

It is another object to provide improved means for controlling the introduction of atomic particles into the anodic space whereby the neutral gas density in the electron tube may be independently adjusted.

It is yet another object to provide improved means for generating ions whereby power loss in the use of electrons from the electron space current may be appreciably reduced.

It is another object to provide means for controlling the balance between the quantities of electrons and ions in the tube.

It is a further object to provide electron optical means whereby an electric space charge field is developed in which ions will be trapped to execute long-lived oscillations through a point-like region in an anodic space. As a corollary, it is another object to reduce electron temperature to a minimum whereby circulatory currents of high order magnitude may be achieved.

Another object is to provide a method of converging a space current onto a common point-like region for developing an electrical field which oscillates ions through said region until the ions interact with each other.

A further object is to provide a method of producing nuclear reactions by establishing an electric field in free space, this field having a potential minimum in a given point-like region and a potential maximum in a surface surrounding said region, then introducing ions into said field which are thereby propelled repeatedly through said region until collisions occur.

Yet another object is to provide a method of producing ionic oscillations through a point-like region in space by concentrating electron flow onto said region for producing a potential gradient which increases progressively radially outwardly from said region, and then introducing ions into the field of said potential gradient, these ions thereby being oscillated through said region.

Other objects will become apparent as the description proceeds.

The above and other objects are accomplished by an electric discharge device comprising means for forming a space current, means for converging said space current toward a reference point in said free space to produce a localized virtual cathode adjacent to that point, and means for propelling projectile particles through said virtual cathode at nuclear-reacting velocities whereby particle collisions will result in nuclear reactions.

For one form of the invention the electric discharge device is of spherical geometry in which a cathode concentrically surrounds an electron permeable anode having an inner, concentric cavity or space. Electrically, this space is spherical. In operation, an electrical discharge composed of high order magnitude electron and ion currents, in this space, develops a radial potential distribution which is, generally speaking, a minimum at the center and a maximum adjacent to the anode. Ions created at points intermediate this center and the anode fall toward and oscillate through the center at velocities dependent upon operating potentials used. With potentials of sufficiently high magnitude, the ions are propelled at nuclear-reacting velocities whereupon ion collisions at the center produce nuclear reactions.

The anode and cathode are uniquely designed and assembled such as to form an electron-optical system wherein the anodic space (spherical in shape) is maintained completely filled with the electrical discharge without the electrons reaching the anode structure itself. Traversing electrons follow radial paths through the space and are kept from being intercepted by the anode, the electron optics directing the electrons through the permeable portions of the anode toward the outer, structural cathode. Electron temperature is maintained at a minimum value resulting in the development of a high order magnitude electron circulatory current which serves in producing the necessary potential gradient in the anodic space.

An ion gun attached to the cathode generates and injects ions directly into the anodic space, means being provided for controlling the quantity of ions so injected. This provides means for adjusting the neutral gas pressure as well as eliminating power losses which are involved if ions are produced by the electron current itself.

Reactant products of the ion or particle collisions at the center vary depending upon operating parameters and gases used; typical of these products are neutrons, X-rays and isotopes.

The above-mentioned and other features and objects of this invention and the manner of attaining them will become more apparent and the invention itself will be best understood by reference to the following description of various embodiments of the invention taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a cross-sectional view, in schematic form, of one embodiment of this invention;

FIG. 2 is a graph used in explaining the operation of the device of FIG. 1;

FIG. 2a is a graph similar to FIG. 2 used in explaining the operation of the invention;

FIG. 3 is a schematic cross-section of the device of FIG. 1 with an inlet gas tube added;

FIG. 4 is a diagrammatic illustration of the space inside the anode element of the preceding figures depicting ionic concentration;

FIG. 5 is a graph used in explaining the operation of the invention;

FIGS. 6a, 6b, and 6c are graphs used in explaining the operation of this system;

FIG. 7 is a schematic cross-section illustration of a complete system utilizing the device of FIG. 1;

FIG. 8 is a perspective illustration of a suitable anode construction;

FIG. 9 is a sectional illustration taken substantially along section line 9-9 of FIG. 8;

FIG. 10 is a cross-sectional view of another embodiment of this invention;

FIG. 11 is a schematic illustration of the device of FIG. 10 showing a plot of the equipotential surfaces produced at the anode;

FIG. 12 is an enlarged sectional view of the anode of FIG. 10;

FIG. 13 is a sectional view, in schematic form, of another embodiment of this invention;

FIG. 14 is a graph used in explaining the operation of the embodiment of FIG. 13;

FIG. 15 is an illustrative graph of the potential distribution within the tube of FIG. 13 due to the combined effects of both the ion and the electron discharge;

FIG. 16 is a curve similar to FIG. 15 of potential distribution inside the anodic space for one mode of operation;

FIG. 17 is a curve similar to that of FIG. 16 but illustrating a different mode of operation;

FIG. 18 is a diagram illustrating the principle of ion bunching in the anodic space;

FIG. 19 is a waveform used in achieving the ion bunching in FIG. 18;

FIG. 20 is a partial sectional illustration of another operating embodiment of this invention utilizing the principles associated with FIGS. 13-19, certain portions thereof being shown in section and others schematically;

FIG. 21 is an enlarged illustration of the anode of FIG. 20;

FIGS. 22 and 23 are partial sectional illustrations of the supports for the two anode elements used with the tube of FIG. 20;

FIG. 24 is a simplified hemispherical illustration of the basic tube structure of FIG. 20 with the anode element removed therefrom;

FIG. 25 is a fragmentary view of the tube of FIG. 20 partially broken away and sectioned and with the dynode elements removed for clarity;

FIG. 26 is a simplified sectional illustration of the tube of FIG. 20 showing the ion gun, the mechanical supports for the anode elements being omitted;

FIG. 27 is a fragmentary sectional illustration of one embodiment of the electron-optical assembly of FIG. 20;

FIG. 28 is a diagrammatic illustration of the electron optics shown in FIG. 27;

FIGS. 29 and 30 are diagrammatic illustrations of alternative forms of electron optics; and

FIGS. 31 and 32 are sectional and front views, respectively, of an alternative collector construction.

Electric field generation

Referring to the drawings, and more particularly to FIG. 1, an evacuated spherical electron tube structure is shown which comprises a spherical cathode shell 20, a spherical anode shell 21, and an intermediate spherical control grid 22, these electrodes being concentrically arranged as shown. The anode 21 and control grid 22 are electron permeable and in this exemplification may be considered as open mesh electrodes. The anode may be the electrical equivalent of 99% open while the control grid may be 95% open. Suitable connections are made to these various electrodes, a lead 23 being connected to the anode 21, a wire 24 leading to the cathode 20, and a wire 25 leading to the control grid 22. Potentials of proper polarity and suitable parameters are applied as shown, the bias potential applied between the control grid and cathode 20 being such as to control electron flow from cathode to anode. The inner surface of the cathode 20 carries an electron-emitting material or apparatus.

With the cathode 20 supplying copious quantities of electrons, a cloud of electrons, or in other words a space charge, is developed in the space between the cathode and the negatively biased control grid. From this cloud, electrons permeate the control grid to oscillate through the tube until captured or intercepted by the anode. Any electrons which may happen to pass back through the control grid will re-enter the electron cloud and thereby not be lost.

With suitable potentials applied to the electrodes, electrons emitted by the cathode surface converge along essentially radial paths toward the center of the tube. Electron flow is accelerated toward the anode by reason of the electric field established between the anode and cathode so that when the electrons reach the vicinity of the anode, they are travelling at high velocity. Inasmuch as the anode is an essentially open structure, in one embodiment being 99% open, the anode itself may be considered as a spherical equipotential electron-permeable surface which exerts an accelerating force on the electrons emitted by the cathode. Upon reaching the anode surface, the electrons will have a velocity corresponding to the potential through which they have fallen and will thereupon travel onwardly, along the same radial paths, toward the geometric center of the anode.

If at this point only a single electron is considered as existing in the space inside the control grid, this electron will travel diametrically through the control grid space as well as the anode space. Because of the potential differential between the control grid and the anode, the velocity of the electron will be affected correspondingly, but because of the fact that the potential inside the anode is uniform, that is to say, constant throughout the anodic space which is free of tangible structure, the electron will experience no velocity-changing force while travelling therethrough. Thus, the electron, upon entering the control grid space, oscillates diametrically across the tube inside the control grid, the electron being considered as starting its travel at or near a given point on the control grid, accelerating toward the anode, traveling with constant velocity through the anode space (which may be characterized as a volume of free space), and then decelerating from the anode to the control grid, the velocity of the electron just before reaching the control grid being zero. This electron will continue its oscillatory travel until it is intercepted by the anode, it being desired that the electron make as great a number of trips as possible before being so lost.

The significance of this single-electron consideration is two-fold, the first recognizing that the normal space potential inside anode 21 is uniform at the value of the anode potential, whereupon an electron travelling across the anodic space does so with uniform velocity and energy, and the second being that the electron oscillates within the space of the control grid a relatively large number of times before it is lost by anode interception.

As the next step in considering tube operation, let it be supposed that only two electrons simultaneously start movement from diametrically opposite points on the control grid. Both of these electrons will be propelled radially toward the exact center of the anodic space so that these electrons will collide at the exact center 26 in the absence of any mutually repelling forces. Inasmuch as the two electrons are negatively charged particles, they will exert mutually repelling forces on each other the moment the anodic space is penetrated so that their respective velocities will progressively decrease until the electrons very nearly touch at the exact center 26. At this point, their respective velocities drop to zero. However, in a practical embodiment the approach of the electrons is not head-on, whereupon they pass each other at minimum velocity rather than stopping. Upon passing each other, the electrons are accelerated outwardly by the mutually repelling forces thereof. Upon leaving the anode, continued return movement results in the electrons losing velocity until they stop adjacent the control grid, whereupon the cycle is repeated.

It may now be noted that, even though the unipotential space inside the sphere 21 exerts no force on a single electron passing therethrough, two electrons approaching each other along a diametral path experience coulomb repulsion and velocity change which serves to create an electric field in the anodic space. This may be thought of as a space charge effect.

Now assuming that a copious quantity of electrons emitted from the cathode permeates the control grid, such electrons will follow diametral paths indicated by the arrows 27 which cross near the center. These electrons will converge toward the center 26 at progressively decreasing velocities until they reach a minimum velocity and thereafter diverge outwardly along essentially the same diameters, accelerating until they pass out through the anode surface 21. As the electrons pass through the interior of the anode 21, they contribute a negative charge to the anodic space so as to progressively decrease the space potential as the center is approached. Thus, at the anodic center a virtual cathode will be produced which can be made to have a potential essentially the same as that of the cathode 20. The total space current (including both inward and outward flow) that is needed to establish the virtual cathode at the center of the anodic space for typical embodiment of this invention is 1500 amperes for an anode potential of 100 kilovolts. This can be shown by calculations based on formulae such as those developed by Langmuir and Blodgett for similar geometries (see Physical Review, vol. 24, p. 53, July 1924). The space current generated in this invention oscillates back and forth through the permeable anode since it does not re-enter the cathode from which it was emitted. It builds up to values much higher than the anode current because the permeance of the anode allows the interception of only a very small fraction of the space current. The instantaneous space current, including both inward and outward flow, is related to the cathode current by the following series:

I(space) = I(cathode) × the sum from 0 to k of Pᵏ

where “P” is the decimal expressing the ratio of open anode area to total anode area and “k” is the number of trips through the anode in both directions made by an electron which started from the cathode at time zero. The variation in space current with time may be found by determining the electron transit time “t” for an electron between its inner and outer limits of travel since this determines how often it passes the anode. Then the current at a specified time T is determined by substituting K = T/t in Equation 1 above. The relation between the anode current and cathode current is the following:

I(anode) = I(cathode) × (1 − P) × the sum from 0 to k of Pᵏ

From 1 and 2 it is clear that

I(anode) = I(space) × (1 − P)

Thus the actual space current in the tube is many times greater than the anode current by a factor corresponding to the reciprocal of the quantity of one minus the effective anode openness “P.” For the previous given effective anode openness of 99%, this factor is 100, giving an anode current of 15 amperes for the 1500 ampere space current requirement above.

The establishment of the space charge inside the anode may be better understood by reference to the graph of FIG. 2 wherein the abscissa represents the diameter of the tube and the ordinate represents the potential distribution inside the tube. Inasmuch as the magnitude of the space charge is dependent upon the amount of space current flowing in the anodic space, the different curves of the graph illustrate the potential of the center 26 for different quantities of current. For a minute quantity of current, it will be seen that the negative charge contribution will reduce the potential at the center according to the curve (a). A larger current will produce a potential distribution according to curve (b), which makes the center more negative. Progressively higher currents produce more pronounced curves (c), (d) and (e), curve (d) representing the preferred operating condition of nearly zero potential at the center, or in other words a center potential slightly positive with respect to the cathode 20. It will be understood that these curves (a) through (e) are representative only to illustrate the fact that intense electron densities at the anodic center 26 are required to drive the potential thereof to the desired value.

Still considering this set of curves, the potential distribution across the entire diameter of the tube due to electrons only starts from zero at the cathode, decreases slightly between the cathode and the grid, and then increases toward the anode potential, while inside the anode sphere 21 it again diminishes to nearly zero at the center 26. This potential distribution has spherical symmetry.

It may now be appreciated that it is possible without any physical means other than space current flow to produce a non-uniform potential distribution in a space enclosed by a permeable equipotential surface (anode 21).

Ion generation

Having explained the basic electronic features of this invention, the next phase of the tube construction and operation will be considered.

This involves the creation inside the anode space of positively charged ions which are controlled in such a manner as to produce a nuclear reaction.

Referring to FIG. 3, like numerals will indicate like parts. A tubular element 28 opens into the interior of the tube through a suitable conductive screen 29. A window or suitable radiation filter 30 is secured over the end of the element 28 to permit viewing ultraviolet or other radiation emitted from the interior of the tube. Laterally extending from the element 28 is an exhaust tubulation 31 which is coupled to a suitable vacuum pump 32 (see FIG. 7). It may be stated at this point that the tube is evacuated by operation of a vacuum pump 32 and associated valving, this vacuum pump being operated continuously or intermittently as needed to achieve the desired operation which will become more apparent from the following description.

It may now be generalized that the anode 21 is supported in the exact center of the cathode 20 by means of a supporting structure comprising a metallic gas inlet tube 33 and a suitable insulator 34. The material forming the tubular element 33 must be able to withstand high temperatures, as is true of the insulator 34. Still further, the tubular element 33 is used to conduct the anode potential to the anode.

As was explained earlier, the cathode 20 is called upon to emit copious quantities of electrons. Preferably, cathode 20 comprises a photoelectric material which may be excited by intense ultraviolet radiation. Under intense ultraviolet radiation, it has been found that aluminum or germanium is photoelectric; therefore, the cathode 20 as well as the supporting structure may consist of aluminum. Still further, to obtain better out-gassing during evacuation, the cathode 20 may be constructed of copper with the electron-emitting surface being coated with a photoelectric material, such as aluminum or germanium, which will emit copious quantities of electrons in response to ultraviolet excitation.

The purpose of the tubular element 28 and window 30 is to permit viewing of the interior of the tube during operation. As will be explained more fully in the following, once the tube becomes fully operative, it will generate its own ultraviolet excitation at or near the center 26, which will serve to produce electron emission from the cathode.

While certain specific design information and details will be given in the following, it is to be understood that this invention is not limited thereto, and that such design details and information are given only for the purpose of describing more clearly and fully the construction and operation of the invention. It will occur as obvious to a person skilled in the art that these design details may be modified in order to secure different performance characteristics; however, these modifications can be made without departing from the scope of this invention as defined by the appended claims.

The order of vacuum which the pump 32 (FIG. 7) must develop is a pressure of 10⁻⁶ to 10⁻⁷ millimeters of mercury in order to permit good outgassing and to insure that inleakage is low so that contaminants will be at a minimum. However, it should be understood at this point that while the pump 32 (FIG. 7) is required to develop this vacuum, the tube will actually be operated at a much higher pressure.

By means of the inlet tube 33 or alternative inlet means small quantities of suitable gasses such as hydrogen, deuterium, tritium, or the like are admitted to the interior of the tube. While different gas pressures may be used, one type of tube operation is achieved by allowing sufficient gas to enter the tube as will raise the pressure to about 10⁻⁴ millimeters of mercury. Of course, the exact pressure will depend upon preferred design characteristics. The pump 32 and associated valving (FIG. 7) is operated in such a manner as to hold this particular degree of vacuum or pressure.

As gas atoms diffuse into the anode 21 and into the paths of the converging electrons, collision of the electrons with the neutral atoms results in positive ion formation. As was explained in connection with FIGS. 1 and 2, there exists a potential distribution inside the anode 21 of nearly zero potential at the center 26 and maximum positive potential at the surface of the anode 21. Thus the positive ions will be attracted toward the center 26 and will attain a maximum velocity corresponding to the potential through which they fall in passing from the point where they are born to the center 26. FIG. 4 is a cross-sectional illustration of the anode 21 only, with the character of ion concentration being indicated by stippling.

If it is assumed that an ion is born or created in that part of the anodic space where the potential difference with respect to center 26 is 50 kilovolts, then the ion will be attracted toward the center. In its flight toward the center, the ion will gain sufficient momentum to carry it beyond the exact center, after which the flight will diminish in velocity until the ion reaches a point in space which again has a potential difference with respect to the center 26 of about 50 kilovolts. The ion will there experience a force of repulsion which will cause it to return toward and through the center again. From this it will be seen that an ion born at some point in space having a potential positive with respect to the center 26 will oscillate along radial paths through the center 26, the length of the oscillating path being determined by the space potential at which the ion was born.

The ions born in the regions adjacent the anode surface 21 will fly toward the zero potential center 26 with extremely high acceleration and velocity and will travel through along a diametral path to the opposite point of the anodic space until the original energy level is attained. Then they return toward the center and repeat this oscillatory transit the same as those ions born near the center. This ion movement is graphically illustrated by means of double-ended arrows in FIG. 4 wherein the arrow 35 indicates the oscillatory path followed by an ion born near the anode surface 21, the arrow 36 indicating the oscillatory path followed by an ion born closer to the center and, lastly, the arrow 37 indicating the oscillatory path followed by ions born adjacent the center 26. All of these ions, since they pass through the center, contribute to the high ion-density which develops therein. However, by far the largest contribution to this ion density is attributable to those ions possessing an energy in excess of 30,000 electron volts. In a typical embodiment of the invention these ions can exceed 95% of the total. The space of heavy ion concentration can have a radius as small as one (1) millimeter. Certain of the slowly moving ions will recombine with an electron near the center 26 and thereby reduce to a neutral atom which experiences no force of movement. Such atoms will tend to drift outwardly and either will be reionized with probability of reappearance of ions of higher energy or will escape from the anodic space and be lost. It is important to avoid reionization of neutralized ions since this will result either in loss of average ion energy or loss from radiation. This is accomplished by utilizing a potential distribution similar to curve (e) of FIG. 2 in which the electrons near the center have insufficient energy to produce appreciable ionization. The proper choice of curve (e) as against curves (d) or (c), for example, is obtained by adjusting the control grid 22 bias. Other slow ions will receive energy from fast ions producing two intermediate velocity ions which are then converted into high energy ions as is explained more fully hereafter. Thus the slow moving ions are effectively scavenged from the center, leaving a high percentage (95%, as previously mentioned) of high energy ions contributing to the center 26 density. Particle concentration inside the anode is graphically illustrated by the curves of FIG. 5, the ion density being represented by the two curves 38.

The ion motion described thus far was based on a potential distribution near the center of the device, which was derived on the assumption that only electrons are present. This distribution will be somewhat affected by the presence of the ions. In FIG. 2a, curve (e) is the potential curve from FIG. 2, in the absence of ions. Curve (f) shows the actual potential curve as resulting from the combined negative electron and positive ion space charges. It is seen that the point P₁, where the electrons reach their lowest velocity, shifts inwardly toward P₂, and that in the space between P₂ and the center, the potential increases to a maximum of P₃.

Take now an ion born at radius r₁ in FIG. 2a. If only electrons were present, it would oscillate through the center of the anodic space for the distance corresponding to the length of double arrow 93. With the corrected potential curve (f), the ion will oscillate through the center for the distance corresponding to the double arrow 94. This motion, generally speaking, is at a higher energy level than that along arrow 93 which is a favorable effect. Simultaneously with the birth of this ion, an electron will be born moving outwardly from the center (arrow 95).

Next, take an ion born at r₂ or r₃. Its oscillation path through the anodic center is indicated by double arrow 96. If the ion originates at r₂, there will also be an electron generated, moving outward as indicated by arrow 97. If, however, r₃ is the point where both the ion and the electron are born, the electron will locally oscillate through the center, as shown by the double arrow 98.

This latter group of electrons which oscillate locally through the center will counteract the positive space charge generated by the ions, because they reduce the potential hump P₃ at the center. This is desirable, because the phenomenon increases the energy of high velocity ions (along arrow 94) which are the ones which initiate the desired nuclear reaction, as described later. It also permits a greater ion density at the center.

The exact quantitative relations will depend on the position of point P₁ which is determined by the original electron current and can therefore be controlled, e.g., by the bias of control grid 22.

Since the space adjacent to and surrounding the anode center, indicated by the symbol P₂, is a relative potential minimum, this space or region is characterized as a virtual cathode. Similarly, since the central point P₃ is a relative potential maximum with respect to the potentials in the center of the anode, it may be termed a virtual anode. Either of these (virtual cathode and virtual anode) may be designated a virtual electrode.

The ion transit time, that is, the time which an ion takes for one traversal of its path, is proportional to the ion path length and inversely proportional to its velocity. In FIG. 4, path 35 corresponds to the higher ion velocity but this path is also longer than the other paths (36, 37). Calculations show that the transit time of the higher energy ion following path 35 is larger than the transit time of lower energy ions such as the ones following the paths 36 and 37. However, the differences in transit times for ions of different energies are not large for the interval from about 30,000 electron volts to 100,000 electron volts.

As has already been explained, the high energy ion will oscillate radially through the anodic space. This oscillatory action will continue until one of three possibilities occurs:

(1) The ion path is changed by the scattering process;

(2) The ion captures an electron and becomes a neutral atom; or

(3) The ion is absorbed by a nuclear reaction.

By scattering process is meant the phenomenon of the forces of repulsion experienced by two ions approaching each other from different directions. For example, assuming that one ion is stationary at the center 26 and another ion is travelling radially inwardly toward this central ion, as the travelling ion approaches the center it will experience a coulomb force of repulsion which will tend to set the central ion into motion and to reduce the velocity of the incident ion. Thus, an energy transfer occurs from the moving ion to the stationary ion, which tends to slow down the moving ion. The net effect is that instead of a fast ion and one at rest, two ions of intermediate velocities are produced. Average energy transfer per encounter is very small, but finally the condition of equi-partition of energy between the particles will be approached.

In the case of capture, an ion gains an electron from a neutral atom which becomes an ion of lower energy than the original ion. This leaves the total number of ions unchanged. This ion must then be accelerated to a higher energy as in the case mentioned above. A nuclear reaction on the other hand will usually remove two ions, which, of course, must be replaced.

In order to increase the probability of the occurrence of nuclear reactions, it is preferable to maintain the oscillatory flight of the high speed incident ions. This means, then, that when an incident ion loses energy upon passing through the center, this energy must be restored.

In order to maintain projectile oscillation, the control grid 22 is modulated for the purpose of varying periodically the space charge potential of the anodic center 26 with respect to the anode 21. The modulating signal is preferably a sine wave having a frequency whose period is slightly greater than the transit or flight time of the ionic particle (projectile) in its travel from one side of the anodic space to the other. FIG. 6a is illustrative of the sine wave modulation which is applied to the control grid 22. This modulation will vary periodically the intensity of the space current converging on the center 26 and will thereupon modulate the potential of this center 26 with respect to the anode 21 as shown in 6b. This center 26 modulation is illustrated in FIG. 6c (similar to FIG. 2 by the dashed line portion 40 of curve (d)) whereby it is shown that the center 26 periodically varies from a potential near zero volts (curve (d)) to a slightly higher potential (curve 40). The limits of this potential variation may be adjusted by means of the grid bias and the modulation amplitude controls.

As a result of this modulation, projectile ions whose transit time is greater than the modulation period will have energy imparted thereto of a reinforcing nature, thereby maintaining their state of oscillation. Ions whose transit times are shorter than the modulation period will lose energy and drop to a longer transit time. It will now appear that the frequency of the modulation is important with two criteria setting the upper and lower frequency limits respectively. The upper frequency limit is determined by the highest ion energy desired. The lower frequency limit is set by the need for preventing ion escape from the anodic space. Preferably the actual frequency is adjusted to fall within these limits.

As will be recalled, a high speed, projectile ion loses an increment of energy upon passing through the anodic center by reason of the scattering process described previously. If this particular ion has a transit time shorter than the modulation period, this increment of energy will be restored, whereupon the projectile will continue its oscillatory flight with increasing amplitude and velocity. As a consequence, the ion exists for a greater length of time with greater probability of producing a nuclear reaction.

Nuclear reaction

If any oscillatory ion should collide with another ion with suitable energy, a nuclear reaction will be produced. There are a very great number of nuclear reactions which are possible. Fusion reactions of an exothermic nature will be specifically considered as one type of reaction which this invention seeks to attain. Power production by such reactions is theoretically proportional to both the amount of energy, Q, released per reaction and the number of reactions taking place per unit time. The number of reactions per unit time is obtained by taking the product of the nuclear cross-section, which expresses the probability for a specific nuclear reaction to occur, the number of ions in the center region 26, and the number of projectile particles passing through this region per unit time. The nuclear cross-section or the probability that a nuclear reaction will occur is a function of the velocity or energy of the projectile particle which in this device is a function of the potential difference between the maximum point of outward travel by the projectile and the center 26. From the above, it is clear that good power-producing reactions require a large nuclear cross-section and also a large Q or reaction energy release.

One reaction which theoretically is outstanding in meeting the above requirements is the tritium reaction with deuterium. The nuclear equation for the process is as follows:

₁H³ + ₁H² + Eₚ → ₂He⁴ + ₀n¹ + (Q + Eₚ)

This states that a triton plus a deuteron plus the sum of their kinetic energies, Eₚ, results in a nuclear reaction whose products are helium 4, a neutron, and the sum of the reaction energy released, Q, and the kinetic energy, Eₚ, possessed by the original triton and deuteron. The reaction energy release, Q, is 17.6 mev. for the example above. This Q value is large compared with the Q values for other possible reactions which in most cases are 3 or 4 million electron volts (mev.). The nuclear cross-section for the reaction shown in 4 peaks at a value of about 5 × 10⁻²⁴ cm.² for projectile energies of 100 kilo-electron volts (kev.). This cross-section value is about 10² times larger than that for most competing reactions when compared at the same projectile energies.

Additional possible reactions are the following:

(5) ₁H² + ₁H² → ₀n¹ + ₂He³ + 3.3 mev.

(6) ₁H² + ₁H² → ₁H¹ + ₁H³ + 4.0 mev.

(7) ₂He³ + ₁H² → ₁H¹ + ₂He⁴ + 18.3 mev.

Reactions 5 and 6 have a lower Q value and a lower 100 kev. cross-section value than reaction 4. Reaction 7 has about the same Q value but a lower 100 kev. cross-section value, making it second in preference to reaction 4.

Power generation

Referring to FIG. 7, the devices of FIGS. 1 and 3 are shown incorporated in a system for producing power. When a suitable anode potential is applied, the current emitted by the cathode 20 is eventually intercepted by the anode, as explained hereinbefore. This current can range as high as 20 amperes with an applied anode potential of 120 kilovolts. The high temperatures produced at the anode by the interception of this current must be dissipated sufficiently rapidly. A heat exchange unit for this purpose is illustrated in FIG. 7 as comprising a spherical water tank 47 in intimate thermal contact with the outer surface of the cathode 20. Enclosing the heat exchange unit 47 is a biological safety shield 48 which may comprise any of the well-known shield materials lead, water, or concrete. A suitable source 49 of gas is connected to the inlet pipe 33 and a power supply 50 is connected between the anode and cathode. A source 51 of modulating voltage and bias is coupled to the control grid 22 for developing the modulated space current previously discussed.

By use of suitable material in the heat exchanger, the heat developed inside the tube may be quickly conducted away and, further, the energy of the reactant products or particles may be transformed by the heat exchanger into heat which is then utilized in a conventional manner to produce power. The above energy of the reactant products will be released in the form of kinetic energy stored in the fusion products, which are alpha particles and neutrons. The total energy, Q + Eₚ (as defined previously), will be about 17.7 mev. and will divide between the alpha particle and neutron inversely as their mass ratio. The alpha will then have an average energy of 3.5 mev. and the neutron an average energy of 14.2 mev. The 3.5 mev. alpha will transfer most of its energy to the tube electrodes where the energy is transformed to heat, that is, in turn, radiated and conducted to the heat exchanger surrounding the tube. The 14.2 mev. neutron will leave the tube and penetrate into the liquid of the heat exchanger. The liquid is selected not only for its efficiency in heat removal, but also for its ability to absorb the neutron's energy as heat. A hydrogenous material or moderator is best suited to absorb the neutron's energy. Light water is especially good for it absorbs the neutrons after moderating their energy, thus giving some shielding effect as well as resulting in the production of heavy water. Heavy water is a good moderator without the large neutron absorption characteristic of light water. The heavy water would be used where it is desirable to produce large quantities of thermal energy neutrons which could be used in conjunction with ₃Li⁶ (lithium-six) to produce tritium with additional thermal energy output as well.

In FIG. 8 is illustrated one form of construction for the anode 21, the preferred material being tungsten and the construction consisting primarily of suitably thin crossed vanes in the form of discs having central apertures punched therein. One particular anode structure is 4 centimeters outside diameter and 2 centimeters inside diameter. Inside diameter for the cathode is 12.7 cm. and that for the control grid is about 12 cm. It will obviously appear that these dimensions may be altered in order to achieve different performance characteristics.

The insulator 34 of FIG. 3 preferably is made of high resistivity aluminum oxide (alumina) of non-porous variety which is capable of contributing to a tight vacuum seal for the tube. As just explained, the anode material is tungsten, this being necessary to withstand the relatively high temperatures generated by anode dissipation, these temperatures ranging as high as 2000° C. The control grid 22 may comprise a gold-plated perforated metal shell which is 95% open and which produces at the most only negligible electron emission. The cathode 20 may be composed of hydroformed hemispherical cups of copper to provide a spherical wall which may be covered with suitable photoelectric material, such as aluminum or germanium, capable of emitting copious quantities of electrons under intense ultraviolet radiation.

The power supply should deliver about 100 kilovolts direct current, e.g., while the control grid bias should be adjusted to the best operating value between plus and minus five (5) volts. The radio frequency supply should deliver about ten (10) volts plus or minus 5 volts in the vicinity of 10⁸ cycles per second.

Summary of operation

At the moment the power supply 50 (see FIG. 7) is turned on, there will be some stray electrons emitted from the cathode 20. This results in the production of a limited number of ions which, in the generation thereof, release a number of secondary electrons by cathode bombardment to produce additional ions. This process is cumulative until the virtual cathode is formed which appears as a tiny spot of light. Ultraviolet radiation resulting from recombination of ions serves to excite further electron emission from the cathode 20. This latter process becomes the major factor in maintaining the electron discharge. Following the establishment of the virtual cathode 20, the resulting ion interaction produces nuclear reactions. The nuclear reactions may serve as a source of power or alternatively the radiations accompanying them may be used for other purposes.

Design summary

From the values for focal length, it is obvious that the dimensions of the electron lens may be calculated, the anode and cathode structure being a part of this lens. Also, as explained under the heading of Capture and Recombination, the gas density may be calculated and adjusted to provide the operating characteristics desired.

In the following tabulation are given typical dimensions of the last-described operating embodiment of this invention, it being understood that these dimensions are given as exemplary only and not as limitations.

Suitable materials:

| Part | Material or value | |---|---| | Dynode 127, 128 | Beryllium copper | | Anode 101a, 125 | Stainless steel (low boron content) | | Cathode shell 100a | Stainless steel (low boron content) | | Collector 130 | Stainless steel | | Bushings 132 | Boron nitride | | Probes 135 and 135a | Sapphire or boron nitride | | Gas used | Tritium and deuterium in equal portions | | Neutral gas pressure | 2 × 10⁹ to 2 × 10¹⁰ neutral atoms per cubic centimeter at 0° C. | | Gas temperature (introduced) | Room temperature | | Anode 101a voltage | 140 or 160 kilovolts | | Anode element 125 voltage | 50% to 75% anode 101a voltage | | RF supply voltage | 0 to 150 volts adjustable at 10⁶ to 10⁸ cycles per second |

While I have described above the principles of my invention in connection with specific apparatus, it is to be clearly understood that this description is made only by way of example and not as a limitation to the scope of my invention.

Claims

What is claimed is:

1. In an electric discharge device for producing nuclear reactions, an envelope having a cathode therein, said cathode having a generally spherical inner surface, an anode positioned inside said cathode and having portions mutually defining an open region in the center portion of said spherical inner surface to provide an equipotential field throughout said region, said anode having other portions respectively which bound a space current region extending diametrically across said cathode through the central portion of said open region, said anode being electron permeable and free of all tangible structure in said space current region, masking elements fixedly positioned between said anode and cathode and extending into the marginal portions of said space current region to intercept electrons in said marginal portions, electron optical means including said anode and said cathode for forming a space current which occupies said space current region and converges toward said central portion, circuit means for applying an electron-collecting potential to said masking elements, means for supplying fusion reactive gas to said open region, and means connected to said cathode and anode for developing said space current to an intensity which produces a virtual electrode surrounding said central portion and a potential gradient which accelerates ions of said gas through said central portion at nuclear reacting velocities.

2. In an electric discharge device for producing nuclear reactions, cathode means for emitting electrons, an electron permeable anode enclosing a region of space free of tangible structure, said means surrounding said anode, means including said cathode means and said anode for forming a space current and for converging said space current toward a reference point in said region for producing a localized virtual cathode, means for preventing the interception of a portion of said space current by said anode, said space current being of a magnitude which produces a potential distribution in said region of minimum negative value adjacent to said virtual cathode and of maximum positive value radially outwardly therefrom adjacent to said anode, ions in said region of space, said minimum and maximum potential values being such as to propel ions through said virtual cathode at nuclear-reacting velocities, and means for periodically varying the radial position of said virtual cathode at a frequency which produces bunching of the ions in said region.

3. In an electric discharge device for producing nuclear reactions, anode means providing an equipotential surface defining a given volume free of tangible structure, means for introducing gas atoms into said volume, cathode means disposed radially outwardly from said anode means, electron-optical means including said cathode means and said anode means for focusing electrons emitted by said cathode means toward a point in said volume to form a virtual cathode in the vicinity of said point, and power supply means for applying a potential to said cathode means and anode means of such magnitude as results in propelling ions of said gas through said virtual cathode at nuclear reacting velocities.

4. In an electric discharge device for producing nuclear reactions, an envelope having a cathode therein, an anode positioned inside said cathode and having portions defining an open region, said anode having other portions respectively which bound a space current region extending rectilinearly through and beyond directly opposite sides of said anode, said space current region having an electron cross-over point in the center portion of said open region and diverging radially outwardly from said point, that portion of the space current region which extends through said anode being free of all tangible structure, and means for providing a gas in the open region of said anode.

5. In an electric discharge device for producing nuclear reactions, an anode having an open interior, said anode and said open interior being generally spherical in shape and concentric with respect to each other, said anode having a plurality of apertures, said apertures being arranged in diametrically opposite pairs, an envelope surrounding said anode and having a plurality of electron emissive surfaces which are in radial registry with said apertures, means including said anode apertures and the respective electron emissive surfaces for producing and focusing a plurality of electron beams onto the center of said open interior thereby providing a virtual cathode in said open interior, there being one electron beam for each of said aperture pairs, and means for admitting a fusion-reactive gas to said open interior.

6. In an electric discharge device for producing nuclear reactions, an anode which bounds a sphere of space, said anode having open areas on diametrically opposite sides of said sphere of space to provide a space current region, said space current region being free of all tangible structure, cathode means having an electron emissive surface radially spaced outwardly from said sphere of space, said anode open areas being essentially in registry with said electron emissive surface so that said space current region extends to said electron emissive surface, a control grid interposed between said anode and cathode means and across said space current region, a predetermined quantity of fusion-reactive gas inside said anode, and means for applying operating potentials to said anode, cathode and control grid.

7. In an electric discharge device for producing nuclear reactions, an anode having an open interior, said anode and said open interior being generally spherical in shape and concentric with respect to each other, said anode having a plurality of apertures, said apertures being arranged in diametrically opposite pairs, an envelope surrounding said anode and having a plurality of electron emissive surfaces which are in radial registry with said apertures, means including said anode apertures and the respective electron emissive surfaces for producing and focusing a plurality of electron beams onto the center of said open interior thereby providing a virtual cathode in said open interior, there being one electron beam for each of said aperture pairs, means for collecting electrons in the peripheral portions of said beams to prevent such electrons from reaching the anode, and means disposed radially beyond said anode for generating and injecting ions into said open interior.

8. In an electric discharge device for producing nuclear reactions, a cathode assembly of spherical configuration, a spherical anode concentrically positioned inside said cathode assembly and having a concentric spherical open region in the center thereof, said anode having a plurality of open portions therethrough which respectively bound space current regions extending diametrically across said cathode assembly and having a common electron cross-over point in the central portion of said open region, said anode being electron permeable and free of all tangible structure in said space current regions, said cathode assembly including a plurality of dynodes radially aligned with said anode open portions respectively, each dynode having an electron-emitting surface facing radially inwardly, means for introducing a gas into said anode open region, and a plurality of collector elements, there being one collector element for each dynode, each collector element surrounding each dynode surface and extending radially inwardly thereof toward said anode, whereby electrons in the outer fringe portions of the respective space current regions are collected by said collector elements.

9. In an electric discharge device for producing nuclear reactions, a cathode assembly of spherical configuration, a spherical anode concentrically positioned inside said cathode assembly and having a concentric spherical open region in the center thereof, fusion-reactive gas in said open region, said anode having a plurality of open portions therethrough which respectively bound space current regions extending diametrically across said cathode assembly and having a common electron cross-over point in the central portion of said open region, said anode being electron permeable and free of all tangible structure in said space current regions, said cathode assembly including a plurality of dynodes radially aligned with said anode open positions respectively, each dynode having an electron-emitting surface facing radially inwardly, the perimeter of each dynode surface being spaced inwardly a given distance from the periphery of the respective space current region, said perimeter being circular and the dynode surface being concave facing said anode, a plurality of collector elements, there being one collector element for each dynode, each collector element being tubular in shape and surrounding the dynode surface perimeter in a location which is intersected by an annular portion of the respective space current region, each collector element extending from the perimetral region of the respective dynode surface inwardly toward said anode, a frusto-conically shaped grid on each dynode extending inwardly toward said anode from each dynode surface perimeter, said grid being electron permeable and disposed inside and radially spaced from said collector element to thereby serve as a suppressor.

10. The method of producing nuclear reactions comprising the steps of (a) converging positive ions of a fusion-reactive gas from spherically arranged sources toward a point-like region in free space, (b) converging electrons from spherically arranged sources toward the same region to thereby form a space charge of ions and electrons around said region, (c) controlling the charge distribution within said space charge to provide a virtual cathode in said region and a bounding virtual anode, and (d) establishing the value of the potential difference between said virtual cathode and virtual anode such that positive ions within said space charge will be propelled through said virtual cathode at nuclear-reacting energies.

11. In a device for producing nuclear reactions, cathode means and anode means disposed one inside the other, the innermost of said cathode and anode means defining a volume centrally located with respect to both which is free of tangible structure, a fusion-reactive gas within said volume, the inner of said cathode and anode means having openings for the traversal therethrough of charged particles, and means including said cathode means and said anode means for accelerating ions of said gas to fusion-reacting energies along paths which converge from a plurality of zones lying on an imaginary spherical surface and intersect in a point-like region within said volume.

12. In a device for producing nuclear reactions comprising cathode means and anode means disposed one inside the other, the innermost of said cathode and anode means defining a volume centrally located with respect to both which is free of tangible structure, a fusion reactive gas within said volume, the inner of said cathode and anode means having openings for the traversal therethrough of charged particles, means including said cathode means, said anode means and ions of said gas forming a space charge in the central portion of said volume, said space charge including electrons and ions of said gas which are so distributed as to produce a substantially spherical electric field which confines target ions in a point-like region in said central portion and oscillates projectile ions through said region at nuclear-reacting energies, whereby fusion reactions result from collisions between said projectile and target ions.

13. The device of claim 12 wherein the inner of said cathode and anode means includes a conductive shell-like element provided with a plurality of peripherally arranged apertures which receive ions and electrons therethrough, said element enclosing said volume and said space charge.

14. The device of claim 12 wherein the inner of said cathode and anode means includes a conductive shell-like element provided with a plurality of peripherally arranged apertures which receive ions and electrons therethrough, said element enclosing said volume and said space charge, and source means disposed adjacent to the outer of said cathode and anode means for generating and projecting ions of said gas into said volume toward said point-like region.

15. In a device for producing nuclear reactions, cathode means and anode means disposed one inside the other, the innermost of said cathode and anode means defining a volume centrally located with respect to both which is free of tangible structure, a fusion-reactive gas within said volume, the inner of said cathode and anode means having openings for the traversal therethrough of charged particles, means including said cathode means, said anode means and ions of said gas for forming a space charge in the central portion of said volume, said space charge including electrons and ions of said gas arranged in a configuration which provides a plurality of enveloping potential sheaths of positive and negative polarity, each sheath being of a polarity different than the adjacent sheath radially outwardly therefrom, the potential of the innermost sheath being adequate to trap and confine a multiplicity of ions as targets, the potential of an outer sheath being of a magnitude which accelerates and oscillates ions as projectiles through said innermost sheath at nuclear-reacting energies, whereby collisions of projectile ions with target ions produce nuclear reactions.

16. In an electric discharge device for producing nuclear reactions, first electrode means providing a spherical chamber free of tangible structure, second electrode means surrounding said first electrode means, third means for applying a potential between said first and second electrode means, means including charged particles, said first, second and third means for producing a potential distribution in said chamber which increases from a minimum value in the central portion of said chamber toward a more positive value radially outwardly from said central portion, means for supplying fusion-reactive gas to said chamber, means for ionizing said gas, the difference of potential between said minimum and positive values being of a magnitude which propels ions of said gas through said central portion at velocities which cause nuclear reactions.

17. In an electric discharge device for producing nuclear reactions, first electrode means defining a volume free of tangible structure, said first means having openings for the traversal therethrough of charged particles, second electrode means surrounding said first electrode means, third means for applying a potential between said first and second electrode means, means including said first, second and third means for producing a potential distribution in said volume which increases from a minimum value in the central region of said volume toward a more positive value radially outwardly from said region, and means for ionizing a fusion-reactive gas at a location external to said volume and for directing these ions through said openings into said volume, the difference of potential between said minimum and positive values being of a magnitude which accelerates ions in said volume through said central region at nuclear-reacting energies.

18. In a device for producing nuclear reactions, cathode means and anode means disposed one inside the other, the innermost of said cathode and anode means defining a volume centrally located with respect to both which is free of tangible structure, the inner of said cathode and anode means being open to the flow of gaseous particles therethrough, a fusion-reactive gas within said volume, means supplying a potential between said cathode and anode means for establishing an electric field therebetween, said cathode means having electron-emissive surface portions facing said volume, means including said cathode and anode means and said potential-supplying means for focusing electrons and ions along converging radial paths in said volume and also for accelerating ions to fusion-reacting energies along said paths.

19. The device of claim 18 wherein said volume is substantially spherical in shape, and said paths have a common intersection in the central portion of said volume, and further including means maintaining said fusion-reactive gas at sub-atmospheric pressure.

20. The device of claim 18 wherein the inner of said cathode and anode means has an inner surface which bounds and defines said volume, said inner surface being substantially spherical in shape and said paths having a common intersection in the central portion of said volume, the outer of said cathode and anode means having spherically arranged conductive portions spaced from the inner of said cathode and anode means and concentric with said volume.

21. The method of producing nuclear reactions in a conductive device permeable to gas flow and a spherically arranged conductive electrode concentrically surrounding said conductive device, said conductive device defining and surrounding a substantially spherical cavity, comprising the step of (a) evacuating said spherical cavity, (b) introducing a heavy hydrogen isotope gas into said cavity at sub-atmospheric pressure, (c) applying a potential between said conductive device and said electrode and ionizing said gas, and (d) establishing the magnitude of said potential at a value at which ions of said gas are directed toward the center of said cavity with sufficient energy to produce nuclear reactions.

22. The method of producing nuclear reactions comprising (a) evacuating a substantially spherical cavity disposed within concentrically arranged and radially spaced anode and cathode devices, one of said devices being inside the other, the inner of said devices being permeable to gas flow, (b) introducing a heavy hydrogen isotope gas into said cavity at sub-atmospheric pressure, (c) applying a potential between said anode and cathode devices for producing an electric field therebetween, and (d) establishing the magnitude of said field and the pressure of said gas at values at which nuclear reactions are produced within said cavity.

23. The method of producing nuclear reactions in an electric discharge device having cathode and anode devices, one of said cathode and anode devices being disposed inside the other and surrounding and defining a volume of free space, the other of said cathode and anode devices surrounding said inside one, comprising the steps of (a) converging electrons within said volume toward a point-like region therein, (b) converging positive ions of a fusion-reactive gas within said volume toward the same region to thereby form a space charge of ions and electrons around said region, (c) and applying a potential to said cathode and anode devices of such value that some of said ions will be propelled through said point-like region at nuclear reacting energies.

24. The method of producing nuclear reactions in an electric discharge device having cathode and anode devices, one of said cathode and anode devices being disposed inside the other and surrounding and defining a volume of free space, comprising the steps of (a) introducing a fusion-reactive gas into said volume, (b) applying a potential between said cathode and anode devices and ionizing said gas, (c) converging electrons within said volume of free space toward a point-like region therein, (d) converging ions of said gas toward the same region thereby to form a space charge of ions and electrons around said region, (e) establishing the magnitude of said potential at a value which produces a space-charge distribution within said volume such that a multiplicity of spaced virtual electrodes of alternating polarity are created, one of said virtual electrodes being innermost and the others enveloping each other successively radially outwardly, said potential further being of a magnitude that develops a difference of potential between two of said virtual electrodes sufficient to accelerate ions through the inner of said two virtual electrodes at nuclear-reacting energies.

25. In a device for producing nuclear reactions, an anode means centrally disposed inside a cathode means, said anode means defining and surrounding a volume centrally located with respect to both means, said volume being free of tangible structure, a fusion-reactive gas within said volume, said anode means being at least partially open to the flow of said gas therethrough, means including said cathode means and said anode means for accelerating ions of said gas to fusion-reacting energies along converging radial paths within said volume having a common intersection, said accelerating means including electron-optical means for focusing electrons in said volume toward said intersection.

26. In a device for producing nuclear reactions, cathode means and anode means disposed one inside the other, the innermost of said cathode and anode means defining a volume centrally located with respect to both which is free of tangible structure, a fusion-reactive gas within said volume, the inner of said cathode and anode means being at least partially open to the flow of said gas therethrough, means including said cathode means, said anode means and ions of said gas for forming a space charge in the central portion of said volume, said space charge including electrons and ions of said gas arranged in a configuration which provides a plurality of enveloping potential sheaths of positive and negative polarity, each sheath being of a polarity different than the adjacent sheath radially outwardly therefrom, the potential of the innermost sheath being adequate to trap and confine a multiplicity of ions as targets, the potential of an outer sheath being of the magnitude which accelerates and oscillates ions as projectiles through said innermost sheath at nuclear-reacting energies, whereby collisions of projectile ions with target ions produce nuclear reactions, and ion gun means disposed adjacent to the outermost of said cathode and anode means for generating ions and projecting the same into said volume toward the region occupied by said innermost sheath.

References Cited by the Examiner

United States patents: 2,189,358 (2/1940) Farnsworth; 2,200,722 (5/1940) Pierce et al.; 2,489,436 (11/1949) Salisbury; 2,884,559 (4/1959) Cooper et al.; 2,928,972 (3/1960) Nelson; 2,994,801 (8/1961) Hanks; 3,022,236 (2/1962) Ulrich et al.; 3,071,525 (1/1963) Christofilos.

Foreign patents: 654,306 (12/1962) Canada.

Reuben Epstein, Primary Examiner.