KR100648407B1 - Tandem target unit and multiple production method for producing c-11 and f-18 simultaneously - Google Patents

Abstract

A method and a composite target unit for simultaneously producing both C-11 and F-18 are provided to effectively produce the C-11 and F-18 by generating nuclear reaction between protons and N2 gas and an H218O condensation material. A composite target unit for simultaneously producing both C-11 and F-18 includes a receiving portion(21), a gas target unit(20), and a condensation material target unit(40). N2 gas is contained in the receiving portion, which is arranged on an illumination path of protons. The gas target unit includes the inlet/outlet holes formed at both sides of the receiving portion for ingress and discharge of protons to and from the receiving portion. An H218O condensation material is contained in the condensation material target unit, which includes a cavity unit having cavities arranged on the illumination path of the protons. The condensation material target unit is coupled with the gas target unit.

Description

Tandem target unit and multiple production method for producing C-11 and F-18 simultaneously}

1 is a view schematically showing an example of a conventional ¹¹ C production target device.

2 is a view schematically showing an example of a conventional ¹⁸ F production target device.

3 is a cross-sectional view schematically showing a composite target unit for simultaneously producing ¹¹ C and ¹⁸ F according to an embodiment of the present invention.

4 is a schematic exploded perspective view of the composite target unit shown in FIG. 3 cut in a plane perpendicular to its longitudinal direction.

5 is an exploded perspective view of the energy attenuator shown in FIG. 3.

6 is a graph schematically showing the relationship between the degree of nuclear reaction between protons and N ₂ gas and the energy of protons.

7 is a graph schematically showing the relationship between the degree of nuclear reaction between the proton and the H ₂ ¹⁸ O concentrate and the energy of the proton.

<Description of the symbols for the main parts of the drawings>

10 ... Flange member

20.Gas targeting device 21 ... Receiving part

22,34 ... Inlet 23,35 ... Outlet

24 ... Space 25,82 ... Inflow channel

26,83 Exhaust Euro 30 Energy Attenuator

31.Front plate 32 ... Front plate

33 Spatial section 40 Concentration target device

50 ... cavity member 51 ... cavity

60 ... front reinforcing member 61 ... front thin film

62,72 through-hole 63 ... front grating

70.Rear reinforcement 71Rear thin film

73. Rear lattice section 80 Cooling element

81 Space unit 100 Target unit

The present invention relates to a complex target unit and a complex production method for producing ¹¹ C and ¹⁸ F simultaneously.

Positron emission tomography is widely used for early diagnosis of tumors and various diseases.

Recently, the scope of diagnosis using Positron Emission Tomography has been expanded, and accordingly, positron emitting radiopharmaceuticals labeled with various positron emitting isotopes have been developed. The most representative of these radiopharmaceuticals include FDG (2- [ ¹⁸ F] Fluoro-2-deoxy-D-glucose), which is used to diagnose cancer, and L- [ ¹¹ C-methyl] methionine, which is useful for the diagnosis of brain tumor among cancer types. There is this.

Isotopes for positron emission tomography, on the other hand, include ¹⁸ F, ¹¹ C, ¹⁵ O and ¹³ N. Of these isotopes, ¹⁵ O and ¹³ N have a short half-life of 10 minutes, which limits their use. However, ¹⁸ F and ¹¹ C have a half-life of 20.4 minutes and 109.7 minutes, respectively, which are longer than ¹⁵ O and ¹³ N to form various compounds. It is used to.

As described above, in order to produce a wide range of ¹⁸ F and ¹¹ C, a target device for producing ¹⁸ F and ¹¹ C should be separately provided. FIGS. 1 and 2 show an example of a conventional target device. It is.

The target device 200 for producing ¹¹ C shown in FIG. 1 includes a receiving portion 210 in which N ₂ gas is accommodated, and a coolant flows to cool heat generated during nuclear reaction between the N ₂ gas and a positron. And a space portion 220 and an inlet 221 and an outlet 222 through which the coolant is introduced and discharged.

In the target device 200, the receiving portion 210 is filled with N ₂ gas, and driven by a separate pumping device (not shown), the cooling water flows into the inlet 221 and the outlet 222 By circulating the space 220 by being discharged to. Thereafter, a positron beam is generated from a particle acceleration device such as cyclotron to cause a nuclear reaction between the N ₂ gas contained in the accommodating portion 210 and the positron, and as a result, ¹¹ C is produced.

On the other hand, the target device 300 for producing ¹⁸ F shown in FIG. 2 is a H ₂ ¹⁸ O concentrate containing H ₂ O in which H ₂ ¹⁸ O is concentrated at least 95%, and the cavity is open at one side. 311 and a cavity member 310 having a space portion 312 through which cooling water flows, a thin film 320 disposed to cover an open portion of the cavity member 310, and a front side from the thin film 320. The other thin film 330 is spaced apart from each other to form a space 325 in which helium flows together with the thin film 320.

In the targeting apparatus 300, the cavity 311 is filled with H ₂ ¹⁸ O concentrate, and a separate pumping device is driven to induce and discharge helium in the direction indicated by the arrow in FIG. In addition to allowing 325 to flow, cooling water flows into the space 312, thereby making it possible to cool the heat generated during the nuclear reaction between the H ₂ ¹⁸ O concentrate and the positron. Thereafter, when the protons generated in the particle acceleration device such as cyclotron are irradiated toward the H ₂ ¹⁸ O concentrate contained in the cavity 311, the protons pass through the thin films 320 and 330 to concentrate the H ₂ ¹⁸ O concentrate. Nuclear reactions result in the production of ¹⁸ F.

However, as described above, the target device 200 for producing ¹¹ C and the target device 300 for producing ¹⁸ F are separately manufactured, and the proton beam is irradiated for each target device 200, 300 to produce ¹¹ C. and after producing ¹⁸ F, respectively, or, if it is not possible to provide a proton beam for each target device (200 300) includes, for example by examining the proton beam to the target device (300) for producing ¹⁸ F produces ¹⁸ F ¹¹ C was produced by replacing the target device 300 for producing ¹⁸ F with the target device 200 for producing ¹¹ C. Therefore, conventionally, ¹¹ C and according to the production of ¹⁸ F had to configure each of the target devices (200,300), ¹¹ C and ¹⁸ F to produce in time as this is required as a significant amount of radiation exposure in the process of replacing the target device There was a problem that can not be avoided.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a composite target unit for simultaneously producing ¹¹ C and ¹⁸ F.

Another object of the present invention is to provide a complex production method for producing ¹¹ C and ¹⁸ F simultaneously.

In order to achieve the above object, the complex target unit according to the present invention produces ¹¹ C by nuclear reaction between protons and N ₂ gases irradiated in one direction and ¹⁸ F by nuclear reaction between the protons and H ₂ ¹⁸ O concentrate. In a composite target unit for producing a, the N ₂ gas is contained in the receiving portion disposed on the irradiation path of the proton, and the receiving for the inlet of the proton into the receiving portion and the discharge of the proton in the receiving portion A gas target device having inlets and outlets respectively formed on both sides of the unit; And a cavity member having a cavity containing the H ₂ ¹⁸ O concentrate and having a cavity disposed on an irradiation path of protons passing through an outlet of the gas targeting device, the concentrate targeting device being coupled to the gas targeting device. It is characterized by including.

In addition, in order to achieve the above another object, the composite production method according to the present invention produces ¹¹ C by the nuclear reaction between the protons and N ₂ gas irradiated in one direction and at the same time the nuclear reaction between the protons and H ₂ ¹⁸ O concentrate In the composite production method for producing ¹⁸ F by the gas target apparatus having a receiving portion for receiving the N ₂ gas, and a concentrate targeting apparatus having a cavity in which the H ₂ ¹⁸ O concentrate is accommodated. An arrangement step of sequentially arranging the irradiation path; Filling the N ₂ gas into a receiving portion of the gas targeting device and filling the H ₂ ¹⁸ O concentrate into a cavity of the concentrate targeting device; An energy calculation step of calculating energy of protons capable of producing ¹¹ C and ¹⁸ F simultaneously; And irradiating protons having the energy calculated in the energy calculation step with the gas targeting device and the concentrate targeting device, wherein the protons are sequentially nuclear reacted with the N ₂ gas and the H ₂ ¹⁸ O concentrate to produce ¹¹ C and ¹⁸ F. It characterized in that it comprises a production step to produce at the same time.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a cross-sectional view schematically showing a composite target unit for simultaneously producing ¹¹ C and ¹⁸ F according to an embodiment of the present invention, Figure 4 is a plane perpendicular to the longitudinal direction of the composite target unit shown in FIG. FIG. 5 is an exploded perspective view of the energy attenuator shown in FIG. 3, and FIG. 6 is a graph schematically showing the degree of nuclear reaction between protons and N ₂ gas and the correlation between proton energies. 7 is a graph schematically showing the relationship between the degree of nuclear reaction between the proton and the H ₂ ¹⁸ O concentrate and the energy of the proton.

3 to 7, the composite target unit 100 of the present embodiment produces ¹¹ C by nuclear reaction ( ¹⁴ N (p, α) ¹¹ C) between protons and N ₂ gases irradiated in one direction. To produce ¹⁸ F by nuclear reaction ( ¹⁸ O (p, n) ¹⁸ F) between the proton and the H ₂ ¹⁸ O concentrate. The composite target unit 100 includes a flange member 10, a gas target device 20, an energy attenuator 30, and a concentrate target device 40.

The flange member 10 is connected to the proton beam line of the particle acceleration device, such as cyclotron.

The gas targeting device 20 is for producing ¹¹ C by nuclear reaction between the protons and the N ₂ gas. The gas targeting device 20 is made of a metal such as aluminum. The gas targeting apparatus 20 includes a receiving portion 21, an inlet 22, an outlet 23, a space 24, an inlet 25, and an outlet 26.

The N ₂ gas is accommodated in the accommodating portion 21, and the accommodating portion 21 is disposed on the irradiation path of the proton. The accommodating part 21 is formed long in the irradiation direction of the said proton. The cross section of the accommodating portion 21, that is, the cross section with respect to the plane perpendicular to the irradiation direction of the protons, is circular. The cross-sectional area of the accommodating portion 21 is formed to increase from the inlet 22 toward the outlet 23. Since the size of the cross-sectional area of the accommodating portion 21 is changed as described above, even if the proton has a characteristic that the cross-sectional area of the plane perpendicular to the one direction increases as the proton proceeds in one direction, the proton loses energy. The nuclear reaction can be minimized.

The inlet 22 and the outlet 23 are formed at both sides of the receiving portion 21, respectively. The protons are introduced into the receiving portion 21 through the inlet 22, and the protons introduced into the receiving portion 21 are discharged through the outlet 23.

The space 24 is a portion in which cooling water circulates to cool heat generated during nuclear reaction between the protons and the N ₂ gas.

The cooling water is supplied to the space portion through the inflow passage 25, and the cooling water supplied to the space portion is discharged through the discharge passage 26. That is, the cooling water flows through the inflow passage 25 by a pumping device (not shown), passes through the space portion 33 of the energy attenuator to be described later, and is supplied to the space portion 24 for circulation. It flows out through (26), so that the heated N ₂ gas is cooled during the nuclear reaction.

The energy attenuator 30 is provided between the inlet port 22 of the gas target device and the flange member 10. Since a known O-ring (not shown) is installed at each of the flange member 10 and the inlet port 22 of the gas target device, the energy attenuator 30 is the inlet port 22 of the gas target device. And the flange member 10 in a hermetically sealed state. The protons are generated from a particle acceleration device such as cyclotron, and the generated protons generally have high energy, and thus do not react well with N ₂ gas. Therefore, the energy attenuator 30 serves to attenuate the proton energy to such an extent that the proton can efficiently nuclearly react with the N ₂ gas.

The energy attenuator 30 includes a front plate 31 and a rear plate 32, a space 33, an inlet 34, and an outlet 35. The front plate 31 and the back plate 32 are disposed to face each other, each made of a metal such as aluminum. The space portion 33 is formed between the front plate 31 and the back plate 32, the cooling water flows in the space 33, the cooling water is the heat generated during irradiation of the protons Cool. Since the inlet 34 is connected to the inlet passage 25, the coolant introduced into the inlet passage 25 is introduced into the space 33 through the inlet 34, and the introduced coolant is It is discharged through the outlet 35. In addition, since the outlet 35 is through the space 24, the cooling water discharged through the outlet 35 is supplied to the space 24. By controlling the thickness of the front plate 31 and the back plate 32 and the width of the space 33, it is possible to determine the degree of attenuation of the energy of the proton.

The energy range of the proton with the best efficiency in the nuclear reaction between the proton and the N ₂ gas is around 7 MeV as shown in FIG. 6, and the most efficient proton in the nuclear reaction between the proton and the H ₂ ¹⁸ O concentrate. The energy range of is around 5 MeV as shown in FIG. However, since the protons pass through the N ₂ gas, their energy is reduced, so if the protons passing through the energy attenuator have energy around 7 MeV, the nuclear reaction between the protons and the N ₂ gas occurs well, but the protons are N _2. As it passes through the gas, it is attenuated to have an energy of 5 MeV or less, making it difficult to react well with the H ₂ ¹⁸ O concentrate. Thus, productivity of ¹¹ C can be increased while productivity of ¹⁸ F is very low. Since the productivity of ¹¹ C and the productivity of ¹⁸ F cannot be maximized at the same time, the energy level of the positron to be investigated must be optimized to adequately guarantee the productivity of ¹¹ C and the productivity of ¹⁸ F.

Set In view of the N ₂ gas and the energy band of the nuclear protons to 13MeV vicinity and setting the energy band of the proton nuclear reaction with H ₂ ¹⁸ O enriched water with 7MeV vicinity, when the use of these energy bands of ¹¹ C Productivity And ¹⁸ F productivity. In addition, in order to produce ¹¹ C and ¹⁸ F using the energy band, the gas targeting device 20 should be disposed earlier on the irradiation path of the proton than the concentrate targeting device 40.

The concentrate targeting device 40 is coupled to the gas targeting device 20. The concentrate targeting device 40 is such that the protons that have passed through the N ₂ gas of the gas targeting device 20 nuclearly react with the H ₂ ¹⁸ O concentrate contained in the concentrate targeting device 40 to produce ¹⁸ F. It is prepared for.

The concentrate target device 40 includes a cavity member 50, a front thin film 61 and a rear thin film 71, a front reinforcement member 60 and a rear reinforcement member 70, and a cooling member 80. Equipped.

The cavity member 50 is made of a metal such as titanium (Ti). The cavity member 50 is formed with a cavity 51 in which the H ₂ ¹⁸ O concentrate is accommodated, and the front and rear of the cavity 51 are open. The H ₂ ¹⁸ O enriched water refers to H ₂ O in H ₂ ¹⁸ O is concentrated to above 95%.

The protons that have passed through the gas targeting device 20 are directed toward the cavity 51, and the protons that are irradiated are such that all of their energy is absorbed by the H ₂ ¹⁸ O concentrate contained in the cavity 51.

The front thin film 61 and the rear thin film 71 are disposed to block the front and the rear of the cavity 51, respectively. The H ₂ ¹⁸ O concentrate filled in the cavity 51 by the front thin film 61 and the rear thin film 71 is kept in the cavity 51 without flowing out. The front thin film 61 and the rear thin film 71 are made of a metal such as titanium (Ti), and the thickness thereof is generally several tens of micrometers.

The front reinforcement member 60 and the rear reinforcement member 70 are coupled to the cavity member 50 so as to support the front thin film 61 and the rear thin film 71, respectively, and thus are shown in FIG. As described above, a front thin film 61 is disposed between the front reinforcement member 60 and the cavity member 70, and a rear thin film 71 is disposed between the rear reinforcement member 70 and the cavity member 50. have. In addition, the front thin film 61 and the rear thin film 71 are coupled in a sealed state by a sealing member (not shown) such as polyethylene. The front reinforcement member 60 and the rear reinforcement member 70 are disposed on the irradiation path of the protons. The front reinforcement member 60 and the rear reinforcement member 70 are made of metal such as aluminum (Al).

The front reinforcement member 60 and the back reinforcement member 70 may be formed of the front thin film 61 and the rear thin film due to the pressure increase in the cavity 51 during the nuclear reaction between the protons and the H ₂ ¹⁸ O concentrate. 71) to prevent each swelling. That is, the H ₂ ¹⁸ O concentrate phase changes due to heat generated during the nuclear reaction, and part of the H ₂ ¹⁸ O concentrate changes into H ₂ ¹⁸ O water vapor, and the front thin film 61 by the pressure increase caused by the H ₂ ¹⁸ O water vapor. ) And the rear film 71 are prevented from bulging in opposite directions, respectively.

The front reinforcement member 60 is provided with a plurality of through-holes 62 penetrating the front reinforcement member 60 in the irradiation direction of the proton. The total area of the through holes formed in the front reinforcing member 60 corresponding to the front opening of the cavity 51 is 80% or more of the total area of the front opening of the cavity 51. The proton is the front grating portion 63, that is, the through holes 62 are not formed in the front reinforcing member 60 and do not pass through the portion between the through holes 62. Protons that do not pass through portion 63 will appear to lose energy. Therefore, the total area of the through holes 62 to be less than 80% of the total area of the front opening of the cavity 51 generates excessive energy loss of the protons, thereby lowering the production efficiency of the ¹⁸ F. Not desirable

The rear reinforcement member 70 is provided with a plurality of through holes 72 penetrating the rear reinforcement member 70 in the proton irradiation direction. The rear grating portion 73, ie, the portion of the rear reinforcing member 70 in which the through holes 72 are not formed and between the through holes 72, not only increases the heat dissipation area but also cooling described later It is formed to form a vortex in the cooling water forcedly circulated in the space portion 81 of the member 80 to more efficiently release the heat generated during the nuclear reaction.

The cooling member 80 is coupled to the rear reinforcement member 70. In the cooling member 80, in order to cool the heat generated during the nuclear reaction, a space portion 81 in which cooling water is forced to convection by a collision jet is formed. The cooling water is introduced into the space portion 81 through an inflow passage 82 as indicated by an arrow in FIG. 3 by a separate pumping device (not shown), and the introduced cooling water is discharged through the discharge passage 83. It is discharged from the space portion 81.

Hereinafter, an example of a process of simultaneously producing ¹¹ C and ¹⁸ F using the composite target unit 100 of the present embodiment configured as described above will be described.

First, the H ₂ ¹⁸ O concentrate is filled into the cavity 51 of the concentrate targeting device 40, and the N ₂ gas is filled into the receiving portion 21 of the gas targeting device 20.

Next, the cooling water is circulated to the space 81 of the cooling member 80 of the concentrate target device 40, and the cooling water is circulated to the space 24 of the gas target device 20. The circulation of the cooling water is to cool the heat generated during the nuclear reaction between the protons and the N ₂ gas and between the protons and the H ₂ ¹⁸ O concentrate.

Subsequently, using SRIM 2003, which is commonly used as an energy loss program, nuclear reaction with N ₂ gas with energy near 13 MeV and nuclear reaction with H ₂ ¹⁸ O concentrate with energy near 7 MeV Optimize the energy of positrons that can be produced by optimizing ¹¹ C and ¹⁸ F.

First, the parameter that affects the energy calculation in the energy calculation step is set as follows.

The front plate 31 and the back plate 32 constituting the energy attenuator 30 are made of aluminum having a density of 2.698 g / cm 3 and have a thickness of 0.75 mm, respectively, and the space between the front plate and the back plate The depth of the portion 33 was set to 3.5 mm, and the cooling water flowed through the entire space portion 33. In addition, the length of the receiving portion 21 of the gas targeting device 20 is 100 mm, and the front thin film 61 of the concentrate targeting device 40 is made of titanium having a density of 4.519 g / cm 3 and the thickness thereof is It was configured to be 0.05mm. The space portion 33 of the energy attenuator is filled with cooling water having a density of 1 g / cm 3, and the receiving portion 21 of the gas target device is filled with N ₂ gas having a pressure of 12 bar (0.015 g / cm 3).

Next, it is assumed that a proton having an energy of 28 MeV, 30MeV, 32MeV, and 35MeV from the cyclotron is irradiated to the composite target unit 100 having the above-described parameters, respectively. In addition, the energy value at the time when the proton having energy passes through the gas target device 20 and the concentrate target device 40 sequentially and irradiates the N ₂ gas and the H ₂ ¹⁸ O concentrate is SRIM 2003 program. Was calculated using the following results.

(1) When proton having energy of 28MeV is investigated

 Part Name  Dimension (mm)  Density (g / cm 3)  Incident energy (MeV)  Post Pass Energy (MeV)  Front panel  0.75 thickness  2.698  28  24.785  Space  3.5 depth  One  24.785  15.528  Backplane  0.75 thickness  2.698  15.528  9.779  Receptacle  100 length  0.015 (pressure: 15 bar)  9.779  0  Front thin film  0.05 thickness  4.519  -  -

As shown in the table, when protons of 28 MeV are irradiated, the protons sequentially pass through the front plate 31, the space 33 and the back plate 32 of the energy attenuator, respectively, and are 24.785 MeV and 15.528MeV, respectively. , Attenuated to have an energy of 9.779MeV. Accordingly, protons having an energy of 9.779 MeV enter the receiving portion 21 of the gas target device, thereby producing ¹¹ C by nuclear reaction between the protons and the N ₂ gas.

On the other hand, as shown in the above table, the protons are all absorbed by the N ₂ gas and thus cannot be irradiated with the concentrate target device, thus failing to produce ¹⁸ F.

(2) When proton having energy of 30MeV is investigated

 Part Name  Dimension (mm)  Density (g / cm 3)  Incident energy (MeV)  Post Pass Energy (MeV)  Front panel  0.75 thickness  2.698  30  26.962  Space  3.5 depth  One  26.962  18.593  Backplane  0.75 thickness  2.698  18.593  13.877  Receptacle  100 length  0.015 (pressure: 15 bar)  13.877  8.328  Front thin film  0.05 thickness  4.519  8.328  7.535

As shown in the table above, when protons of 30 MeV are irradiated, the energy of the protons is attenuated by energy of 13.877MeV and is incident on the receiving portion 21 of the gas target device, and thus the nuclear reaction between the protons and the N ₂ gas. Will produce ¹¹ C.

In addition, unlike the case of irradiating 28 MeV energy, the protons having passed through the N ₂ gas have an energy of 8.328 MeV, which passes through the front membrane 61 of the concentrate target device 40 to be 7.535 MeV. The energy is irradiated with the H ₂ ¹⁸ O concentrate contained in the cavity 51. Thus, a nuclear reaction between the proton and the H ₂ ¹⁸ O concentrate occurs, thus producing ¹⁸ F.

(3) When proton having energy of 32MeV is investigated

 Part Name  Dimension (mm)  Density (g / cm 3)  Incident energy (MeV)  Post Pass Energy (MeV)  Front panel  0.75 thickness  2.698  32  29.130  Space  3.5 depth  One  29.130  21.450  Backplane  0.75 thickness  2.698  21.450  17.343  Receptacle  100 length  0.015 (pressure: 15 bar)  17.343  13.042  Front thin film  0.05 thickness  4.519  13.042  12.488

As shown in the table, when protons of 32MeV are irradiated, the protons are sequentially attenuated, and the H ₂ contained in the concentrate targeting device 40 is 17.343MeV in the N ₂ gas contained in the gas targeting device 20. ₂ ¹⁸ O concentrate was irradiated with 12.488MeV. However, the proton energies irradiated to the N ₂ gas and the H ₂ ¹⁸ O concentrate, respectively, were 17.343MeV and 12.488MeV, respectively, which were optimized by optimizing ¹¹ C and ¹⁸ F as described above with reference to FIGS. 6 and 7. It is not desirable as it is beyond the range of energy that can be produced efficiently.

(4) When proton having energy of 35MeV is investigated

 Part Name  Dimension (mm)  Density (g / cm 3)  Incident energy (MeV)  Post Pass Energy (MeV)  Front panel  0.75 thickness  2.698  35  32.345  Space  3.5 depth  One  32.345  25.454  Backplane  0.75 thickness  2.698  25.454  21.946  Receptacle  100 length  0.015 (pressure: 15 bar)  21.946  18.522  Front thin film  0.05 thickness  4.519  18.522  18.101

As shown in the table above, when protons of 35MeV are irradiated, the protons are sequentially attenuated, so that the N ₂ gas contained in the gas targeting device 20 is 21.946MeV, and the H contained in the concentrate targeting device 40. ₂ ¹⁸ O concentrate is irradiated with 18.101MeV. However, the proton energies irradiated to the N ₂ gas and the H ₂ ¹⁸ O concentrate, respectively, are 21.946MeV and 18.101MeV, respectively, which were optimized by optimizing ¹¹ C and ¹⁸ F as described above with reference to FIGS. 6 and 7. It is not desirable as it is beyond the range of energy that can be produced efficiently.

In summary, the positron irradiated to the N ₂ gas can be set to have an energy around 13 MeV only when protons having an energy of 30 MeV are irradiated, and the positron irradiated to the H ₂ ¹⁸ O concentrate. Can be set to have an energy around 7 MeV, thus producing ¹¹ C and ¹⁸ F most efficiently. In addition, the energy range of protons capable of optimally producing ¹¹ C and ¹⁸ F in the vicinity of 30 MeV is calculated in the same manner, and it can be seen that they are 29.5 MeV to 30.5 MeV.

Therefore, the protons should be set to have an energy of 29.5 MeV to 30.5 MeV. If the protons irradiated from the particle acceleration device such as cyclotron have an energy of less than 29.5 MeV, the protons are only absorbed by the N ₂ gas contained in the gas target device 20 after passing through the energy attenuator 30 and concentrated. It will not be possible to irradiate the H ₂ ¹⁸ O concentrate contained in the water targeting device, and thus will not be able to produce ¹¹ C and ¹⁸ F simultaneously. On the other hand, if the protons irradiated from the particle acceleration device such as cyclotron have an energy greater than 30.5 MeV, the energy of the positron irradiated to the N ₂ gas and the H ₂ ¹⁸ O concentrate becomes excessively high, resulting in ¹¹ C and ¹⁸ F. It is not desirable to produce optimally.

Based on the results obtained in the energy calculation step as described above, if the proton having an energy of 29.5MeV to 30.5MeV is irradiated with the composite target unit 100, the protons are sequentially concentrated in the N ₂ gas and H ₂ ¹⁸ O concentrate. Nuclear reaction results in the production of ¹¹ C and ¹⁸ F simultaneously.

On the other hand, as described above, in order to confirm that ¹¹ C and ¹⁸ F can be produced simultaneously, the following experiment was performed.

The front plate 31 and the back plate 32 constituting the energy attenuator are made of aluminum having a density of 2.698 g / cm 3 and have a thickness of 0.75 mm, respectively, and a space portion 33 between the front plate and the back plate. ) Was set to 3.5 mm and set such that the coolant flows through the entire space 33. In addition, the length of the receiving portion 21 of the gas targeting device 20 is 100 mm, and the front thin film 61 of the concentrate targeting device 40 is made of titanium having a density of 4.519 g / cm 3 and the thickness thereof is It was configured to be 0.05mm. Then, the space portion 33 of the energy attenuator is filled with cooling water having a density of 1 g / cm 3, and the receiving portion 21 of the gas target device is filled with N ₂ gas having a pressure of 12.8 bar, and the cavity of the concentrate target device. (51) was charged with H ₂ ¹⁸ O concentrate.

Then, the energy of the proton beam was set to 30 MeV, and the proton beam was irradiated for 1 hour while the current of the proton beam was raised from 5 μA to 20 μA and maintained at 20 μA. This proton beam irradiation produces ¹¹ C and ¹⁸ F by 300 mCi and 585 mCi, respectively.

As mentioned above, the present invention has been described in detail with reference to preferred embodiments, but the present invention is not limited to the above embodiments, and various modifications may be made by those skilled in the art within the technical idea of the present invention. It is obvious.

According to the present invention of the above-described configuration, by investigating protons capable of producing ¹¹ C and ¹⁸ F at the same time, by making the protons nuclear reaction with the N ₂ gas and H ₂ ¹⁸ O concentrate sequentially ¹¹ C and ¹⁸ F Can be produced at the same time.

Claims (8)

In the ¹¹ C by the nuclear reaction between the proton and the N ₂ gas is irradiated in one direction, and at the same time producing a composite target unit for the production of ¹⁸ F by the nuclear reaction between the protons and H ₂ ¹⁸ O enriched water, A receiving part which receives the N ₂ gas and is disposed on an irradiation path of the proton, A gas target device having inlets and outlets respectively formed at both sides of the accommodating unit for inflow of the protons into the accommodating unit and discharge of the protons in the accommodating unit; And And a cavity member having a cavity containing the H ₂ ¹⁸ O concentrate and having a cavity disposed on an irradiation path of the protons passing through the outlet of the gas targeting device, the concentrate targeting device being coupled to the gas targeting device. Complex target unit, characterized in that. The method of claim 1, The receiving portion of the gas target device is formed long in the irradiation direction of the proton, The cross section with respect to the plane perpendicular | vertical to the irradiation direction of the said proton of the said accommodating part is formed so that the cross-sectional area may become large from the said inlet toward the said outlet. The method of claim 1, And an energy attenuator for attenuating the energy of the protons flowing into the inlet of the gas target device. The method of claim 3, wherein The energy attenuator is a composite target unit, characterized in that it is disposed opposite to each other and having a front plate and a back plate forming a space portion for the cooling water flow therebetween. The method of claim 1, The cavity of the cavity member is opened forward and rearward, The concentrate target device, A front thin film and a rear thin film arranged to block the front and the rear of the cavity; A front reinforcement coupled to the cavity member to support the front thin film and the rear thin film, respectively, to prevent the thin films from swelling due to a rise in pressure in the cavity during the nuclear reaction. Member and rear reinforcement member, And the plurality of through holes penetrating the front reinforcing member in the irradiation direction of the protons. In the composite production method for producing ¹⁸ F by the nuclear reaction between the proton and the H ₂ ¹⁸ O concentrate while producing ¹¹ C by nuclear reaction between the proton and N ₂ gas irradiated in one direction, Arranging a gas target device having a receiving portion for accommodating the N ₂ gas and a concentrate targeting device having a cavity for accommodating the H ₂ ¹⁸ O concentrate on the irradiation path of the protons; Filling the N ₂ gas into a receiving portion of the gas targeting device and filling the H ₂ ¹⁸ O concentrate into a cavity of the concentrate targeting device; An energy calculation step of calculating energy of protons capable of producing ¹¹ C and ¹⁸ F simultaneously; And The protons having the energy calculated in the energy calculation step are irradiated with the gas targeting device and the concentrate targeting device, and the protons are sequentially nuclear reacted with the N ₂ gas and the H ₂ ¹⁸ O concentrate to obtain ¹¹ C and ¹⁸ F. Composite production method characterized in that it comprises a production step to produce at the same time. The method of claim 6, The gas target device is a composite production method characterized in that the energy attenuator for attenuating the energy of the protons flowing into the N ₂ gas. The method according to claim 6 or 7, The energy of the protons calculated in the energy calculation step is 29.5MeV to 30.5MeV, characterized in that the composite production method.

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