In-situ reconstruction method for temperature time evolution process of radiation source on surface of sample in ICF black cavity

Abstract

The invention discloses an in-situ reconstruction method for the temperature and time evolution process of a radiation source on the surface of a sample in an ICF black cavity, and the method comprises the steps: injecting laser into the black cavity to generate an X-ray radiation field, and carrying out the synchrotron radiation ablation of a thick Al shock wave sample and a thin Al ablation sample which penetrate through a diagnosis hole in an equatorial plane; obtaining experimental data such as the moment when shock waves of the shock wave sample come out of the interface of the sample, the average transmission speed of the shock waves in the sample, and burn-through radiation flow of multiple energy sections of the ablated sample through precise measurement; constructing a radiation source temperature curve model, and generating a one-dimensional simulation data set of the time when the Al sample shocks out of the interface and the average speed by using a one-dimensional radiation fluid program; adopting a Bayesian inversion method to carry out probability matching on a shock wave interface-out moment, an average speed and a simulation data set which are measured by an experiment, and establishing posterior probability distribution of an intracavity radiation source temperature model parameter so as to solve and obtain an MAP solution; and the prediction accuracy of the MAP solution on the radiation ablation characteristic of the ablation sample is simulated and verified through a radiation fluid program.

Description

Technical Field

[0001] This invention relates to the field of X-ray radiation flow detection technology in ICF, specifically to an in-situ reconstruction method for the time evolution of the radiation source temperature on the sample surface inside the ICF black cavity. Background Technology

[0002] In ICF physics research, the laser-to-X-ray conversion efficiency calculated by various models through radiation fluid simulations is generally higher than the experimentally measured values. This discrepancy indicates the existence of physical mechanisms that have not been fully considered by existing models, leading to energy loss—the long-standing "energy deficit" problem in ICF research. This problem directly results in a decrease in the accuracy of implosion performance predictions, becoming one of the core bottlenecks restricting the realization of high-gain fusion.

[0003] Indirect ICF (Inductively Coupled Flame) propulsion involves injecting multiple laser beams into the surface of a black cavity made of high-Z material. This ablation of the cavity walls generates soft X-ray radiation. The X-rays are repeatedly reflected within the black cavity, forming a near-blackbody radiation source. This source then irradiates a target containing deuterium-tritium fusion material at its center, driving it to undergo implosion compression and fusion reactions. In ICF engineering research, accurately characterizing the evolution of the X-ray radiation flux intensity sensed on the target surface within the black cavity over time is crucial for achieving ignition and high gain.

[0004] Currently, traditional methods measure the evolution of radiation energy flow overflowing from the black cavity inlet over time. Under the assumption of uniform radiation temperature within the black cavity, this is equivalent to the time evolution of radiation temperature on the sample surface within the cavity. In Europe and America, the Dante broadband spectrometer is primarily used, while in my country, the FXRD flat-response X-ray radiation flow detector is mainly employed. However, the diagnostic physical quantity of this method is the radiation flow overflowing from the black cavity inlet, which mainly originates from X-ray radiation reflected from the cavity walls, not from the X-ray radiation incident on the sample or target surface. Influenced by factors such as spatial inhomogeneity of the radiation field, intracavity plasma motion, and the diagnostic response characteristics of X-ray radiation flow, it is difficult to represent the radiation temperature evolution experienced by the sample surface.

[0005] Another method involves irradiating the sample with X-rays within a black cavity. A portion of the radiation is reflected or absorbed by the sample and then re-emitted, while the remaining radiation is absorbed by the sample material and converted into matter energy, forming a forward-propagating shock wave within the sample. The reflected or re-emitted X-ray radiation flow is measured using XRD or other radiation flow meters. Simultaneously, the propagation velocity of the shock wave is measured using SOP (Striped Pyrometer) or VISAR (Velocity Interferometer System for Arbitrary Reflectors). Combining this with radiation fluid simulation programs, theoretical and experimental results, the radiation source temperature at the incident sample surface is simulated and inverted. Because the measured radiation energy flow at the sample is low and easily interfered with by surrounding radiation, the diagnostic requirements are extremely high. Early methods, limited by technology and lacking the capability to measure reflected and re-emitted radiation flow, employed radiation fluid simulations to learn the calibration relationship between the peak radiation temperature at the sample and the shock wave velocity. This allowed for the in-situ determination of the peak radiation temperature at the sample, given only the shock wave velocity, but it could not provide the time history behavior. Since 2015, my country has proposed combining X-ray radiation flow detection technology from FXRD with pinhole imaging technology to develop spatially resolved X-ray radiation flow diagnostic technology. Experimentally, this technology can simultaneously measure the shock wave propagation velocity within a sample and the time evolution data of the reflected / re-emitted radiation flow. This marks the initial development of a method for retrieving the time history behavior of in-situ radiation flow. However, this method relies on multidimensional radiation fluid simulation. Only when the simulation results for shock wave velocity and re-emitted radiation flow data match the experimental results can the simulation indirectly provide the time evolution history of the radiation source temperature of the incident sample. This method is highly dependent on complex radiation fluid simulations. As is well known, current radiation fluid simulation programs still suffer from a series of problems. For example, the accuracy of material parameters such as radiation opacity and equations of state is questionable; the completeness of non-local effects such as self-generated magnetic field effects and kinetic effects in electronic heat conduction models is insufficient. Often, numerous phenomenological, non-physical correction factors need to be introduced to achieve a match between the simulated and experimentally measured shock wave velocity and re-emitted radiation flow. This results in insufficient accuracy and hinders widespread application of the method.

[0006] Therefore, there is an urgent need to invent a new method that does not rely on complex multidimensional radiation fluid simulation and can diagnose the temperature evolution of radiation sources inside black cavities or on sample surfaces in situ, in order to solve the existing technical problems. Summary of the Invention

[0007] In view of this, the present invention provides an in-situ reconstruction method for the time evolution of the radiation source temperature on the sample surface inside an ICF black cavity. This method does not rely on a complex multidimensional radiation fluid simulation iterative process.

[0008] To achieve the above objectives, the technical solution of the present invention is as follows:

[0009] A method for in-situ reconstruction of the time evolution of the radiation source temperature on the surface of a sample within an ICF black cavity, the key of which includes the following steps:

[0010] Step S1: The black cavity is fixed at the center of the vacuum target chamber using a special target frame. Both the upper and lower ends of the black cavity are provided with injection holes.

[0011] Step S2: Multiple laser beams are injected into the black cavity through injection holes at both ends, generating strong X-rays and forming a rising radiation source. A flat-response radiation flow detector is used to measure the temperature evolution of the radiation source within the black cavity over time through the injection holes. ;

[0012] Step S3: Two through-hole diagnostic holes are opened on the equatorial plane of the black cavity. A shock wave sample 1 is placed on one end of the diagnostic hole, and an ablation sample 25 is placed on the other end. The ablation sample 25 is made of the same material as the shock wave sample 1. The X-ray radiation generated by the black cavity irradiates and ablates the surfaces of the shock wave sample 1 and the ablation sample 25. The X-ray radiation stream forms a shock wave in the shock wave sample 1 and exits the rear surface of the shock wave sample 1. The X-ray radiation stream burns through the ablation sample 25 and exits from the rear surface of the ablation sample 25.

[0013] Step S4: Using a time-resolved shock wave diagnostic instrument, measure the shock wave exit time of shock wave sample 1. and shock wave speed The radiation burn-through energy flow curves penetrating the surface of the ablated sample 25 were measured using a radiation dosimeter.

[0014] Step S5 yields the radiation source temperature curve model in exponential function form:

[0015] (1)

[0016] In the above formula, The pulse width of the laser. The peak radiation source temperature, The time evolution factor of radiation source temperature. This is the ratio of the radiation source temperature on the sample surface at the peak time to the radiation source temperature measured by the injection orifice plane response radiation flow detector, etc. To balance the injection orifice radiation source temperature measured by a radiation flow detector, a radiation source distribution function after the laser beam ends is given. These two parameters together constitute the radiation source temperature distribution function over time throughout the entire period. This is achieved by adjusting the radiation source temperature parameter in the formula. and A series of radiation source temperature distribution curves over time were obtained and used as input for radiation fluid simulation. The radiation fluid program was then used to calculate the moment when the shock wave penetrated the back interface during the interaction between the radiation source and the shock wave sample 1. and shock wave speed From a one-dimensional simulation dataset, a quantitative mapping relationship between radiation source temperature parameters and shock wave characteristic diagnostic quantities was extracted;

[0017] Step S6: Using the Bayesian inversion method, the radiation source temperature parameters of the incident sample are established by probabilistically matching the experimentally measured shock wave exit time and velocity with the simulated dataset. and The posterior probability distribution is obtained by solving for the maximum a posteriori probability solution. , This is the radiation source temperature on the sample surface;

[0018] Step S7, based on the reconstructed sample surface radiation source temperature The radiation ablation energy flux of sample 25 was simulated and calculated, and compared with the experimental measurement results to cross-validate the reconstructed radiation source temperature.

[0019] By employing the aforementioned structure and innovatively introducing the moment of shock wave exiting the sample interface as a key constraint parameter, and combining it with multiple physical quantities such as shock wave velocity for inversion, in-situ reconstruction of the temporal evolution history of the radiation source temperature was achieved. Furthermore, cross-validation was conducted using experimental data on radiation burn-through energy flux across multiple energy bands, significantly improving the accuracy and precision of the reconstructed radiation source temperature evolution history.

[0020] Preferably, in step S1, the black cavity is a cylindrical cavity, a spherical cavity, or an irregularly shaped cavity.

[0021] Preferably, the substrate thickness of the shock wave sample 1 is... Greater than The thickness of the ablation sample 25 .

[0022] Preferably, in step S4, the time-resolved shock wave diagnostic instrument is a stripe radiation pyrometer or an arbitrary reflective surface velocity interferometer system.

[0023] Preferably, in step S4, the radiation dosimeter includes a local radiation flow measurement system and a three-chromatograph.

[0024] Preferably, the material of the shock wave sample 1 is Al.

[0025] Preferably, the shock wave sample 1 is a five-step sample with a base thickness of 60 μm and a step thickness of 20 μm, and the ablation sample 25 is a planar sample with a thickness of 26 μm.

[0026] Preferably, the laser is a square wave laser.

[0027] Compared with the prior art, the beneficial effects of the present invention are:

[0028] 1. The in-situ reconstruction method for the temporal evolution of radiation source temperature on the sample surface within an ICF black cavity, provided by this invention, innovatively introduces the moment of shock wave exiting the sample interface as a key constraint parameter. Combined with multiple physical quantities such as shock wave velocity, inversion is performed, achieving in-situ reconstruction of the radiation source temperature temporal evolution. Simultaneously, cross-validation is conducted using experimental data from radiation burn-through energy flux across multiple energy bands, significantly improving the accuracy and precision of the radiation source temperature evolution reconstruction.

[0029] 2. Compared with traditional methods that only use shock wave velocity to constrain the physical process, this method adds constraint on the moment when the shock wave passes through the sample interface, which improves the accuracy of reconstructing the radiation temperature.

[0030] 3. By introducing Bayesian probability analysis, a one-to-one mapping relationship between parameterized radiation temperature and shock wave can be quickly established. This avoids the problem of traditional methods being heavily dependent on the accuracy of multidimensional radiation fluid simulation models and material property parameters, thus improving the efficiency of the method and reducing the difficulty of its implementation. Furthermore, since the iterative process of multidimensional radiation fluid simulation is extremely computationally intensive, the new method can save computational resources. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the process of the present invention;

[0032] Figure 2 This is a schematic diagram of the target structure according to an embodiment of the present invention;

[0033] The components include: 1 black cavity, 11 diagnostic port, 2 injection port, 3 laser, 4 shock wave sample 1, 5 ablation sample 25, 6 stripe radiation pyrometer (SOP), 7 local radiation flow measurement system (SRFD), 8 three-color chromatograph (XSC), and flat response radiation flow detector (FXRD).

[0034] Figure 3 The image shown is a time-stamped shock wave image measured in an embodiment.

[0035] Figure 4 The figure shows the temperature-time evolution curve of the radiation source on the sample surface, reconstructed in situ in the embodiments. Radiation source temperature profile measured with injection hole Comparison chart;

[0036] Figure 5 This is a table comparing experimental measurement results with simulation results. Detailed Implementation

[0037] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0038] Please refer to Figure 1 and2 An in-situ reconstruction method for the time evolution of radiation source temperature on the sample surface within an ICF black cavity is proposed. This method aims to reverse the evolution of radiation temperature over time at a local location within the cavity of an X-ray generated by a square laser pulse irradiating a high-Z black cavity. The steps are as follows:

[0039] Step S1: The black cavity 1 is fixed at the center of the vacuum target chamber by a special target frame. Both the upper and lower ends of the black cavity 1 are provided with injection holes 2.

[0040] Step S2, laser irradiation of a high-Z black cavity target to generate a strong X-ray source: Multiple laser beams 3 are injected into the black cavity 1 through injection holes 2 at both ends. The laser beams 3 interact with the cavity walls to generate X-ray radiation, i.e., strong X-rays, forming a near-Planck spectrum radiation source. The requirement is to generate a rising radiation source, i.e., in... During the time period, the radiation source temperature showed an increasing trend over time; the temperature evolution data of the radiation source inside the black cavity 1 was measured from the injection hole 2 using an FXRD (flat response radiation flow detector 9). In this embodiment, laser 3 is a square wave laser, and black cavity 1 is a cylindrical cavity, spherical cavity, or irregular cavity, wherein the irregular cavity can be U-shaped, I-shaped, or drum-shaped.

[0041] Step S3: X-ray irradiation and ablation of the sample within the black cavity: Two through-hole diagnostic holes 11 are opened on the equatorial plane of the black cavity 1. A shock wave sample 14 is placed on one end of the diagnostic hole 11, and an ablation sample 25 of the same material is placed on the other end. The shock wave sample 14 is a standard thickness sample, and the ablation sample 25 is a thin sample. Both samples are made of Al (aluminum) material. The substrate thickness of the shock wave sample 14 is... Must satisfy greater than The thickness of ablation sample 25 Must meet The unit of thickness is μm. The unit is ns. The peak radiation source temperature is expressed in eV.

[0042] The X-ray radiation generated inside the black cavity 1 drives the ablation of the cavity wall or the surface of the shock wave sample 14 and the ablation sample 25 inside the cavity. In this embodiment, the X-ray radiation generated inside the black cavity 1 irradiates and ablates the surface of the shock wave sample 14 and the ablation sample 25. The thicker shock wave sample 14 cannot be burned through, and the shock wave formed by the X-ray radiation flow will pass through the rear surface of the shock wave sample 14. The thinner ablation sample 25 can be burned through by the X-ray radiation flow. After burning through, the radiation flow passes through the rear surface of the ablation sample 25.

[0043] Step S4: Obtain high-precision experimental data on the time, velocity, and burn-through radiation flow of the shock wave exiting the sample interface: Using a time-resolved shock wave diagnostic instrument, simultaneously measure the time of the shock wave exiting the interface of the shock wave sample 14 from the rear surface of the shock wave sample 14. and shock wave speed The evolution of X-ray radiation flux through a certain spectral energy band or point from the surface of the ablated sample 25 over time is measured using a radiation dosimeter to obtain the radiation burn-through energy flux curve. In this embodiment, the radiation burn-through energy flux through multiple spectral energy bands from the surface of the ablated sample 25 can be measured using a radiation dosimeter to obtain high-precision experimental data.

[0044] In this embodiment, the time-resolved shock wave diagnostic instrument is a striped radiation pyrometer (SOP) or an arbitrary reflective surface velocity interferometer system (VISAR). Preferably, the time-resolved shock wave diagnostic instrument is a striped radiation pyrometer 6. The radiation dosimeter includes a localized radiation flow measurement system 7 (SRFD) and a three-chromatograph 8 (XSC).

[0045] Step S5: Generate a radiation shock wave simulation dataset and construct a radiation source temperature curve model: using a pulse width of A square-wave laser generates an X-ray radiation source with an upward trend, resulting in a radiation source temperature curve model in the form of an exponential function, i.e. At that time, the radiation source temperature curve on the sample surface approximates an exponential function, as shown in the following formula:

[0046] (1)

[0047] In the above formula, The pulse width of the laser. The peak radiation source temperature, The time evolution factor of radiation source temperature. This is the ratio of the radiation source temperature on the sample surface at the peak moment to the radiation source temperature measured by the radiation flow detector 9 at injection hole 2. To measure the radiation source temperature of injection hole 2 as measured by radiation flow detector 9, the radiation source distribution function after the square wave laser ends is given. Together, these two functions form the radiation source temperature distribution function over time for the entire period. This is achieved by adjusting the radiation source temperature parameter in formula (1). and A series of radiation source temperature distribution curves over time were obtained and used as input for radiation fluid simulation. The radiation fluid program was then used to calculate the moment when the shock wave penetrated the back interface during the interaction between the radiation source and the shock wave sample 14. and shock wave speed From a one-dimensional simulation dataset, the radiation source temperature parameter was extracted. , ) and shock wave characteristic diagnostic quantity (exit time) ,speed The quantitative mapping relationship of ).

[0048] Step S6, invert to obtain the maximum a posteriori probability solution. Using the Bayesian inversion method, the radiation source temperature parameters of the incident sample are established by probabilistically matching the experimentally measured shock wave exit time and velocity with the simulated dataset. and The posterior probability distribution is obtained by solving for the maximum a posteriori probability solution. This study achieves the optimal solution inversion of the time evolution history of the radiation source temperature in a black cavity based on multiple physical quantity constraints. This is the radiation source temperature of the sample surface.

[0049] Step S7: Cross-validate the inversion results using radiation ablation experimental data: based on the reconstructed sample surface radiation source temperature. Radiation fluid simulations were conducted on ablation sample 25 to obtain simulation data of radiation burn-through energy flow in multiple spectral bands, i.e., simulation calculations were performed using a radiation fluid simulation program. Radiation ablation sample 25 was performed, and the radiation ablation energy flow from multiple spectral bands that emerged from the surface of the ablated sample 25 was compared with the experimental measurement results to cross-verify the reconstructed radiation source temperature.

[0050] Next, we will verify the feasibility of this method through experiments. The specific steps are as follows:

[0051] Step 1: 48 laser beams are used, with 24 beams injected into each of the two ends of the black cavity 1 through injection holes 2. The wavelength of the laser is 351nm, the energy of a single laser beam is ~3000J, and the laser pulse width is a ~3.2ns shaping pulse. Among them, 0~2ns is a square wave, which is used to generate a radiation source temperature with a continuously rising temperature, and 2~3.2ns is a shaping pulse, which is used to generate a radiation source temperature with a peak radiation temperature greater than 200eV that is approximately isothermal.

[0052] Step 2, taking the black cavity 1 as an example with two cylindrical cavities at both ends, the cavity length is 3800µm and the diameter is 2300µm. Injection holes 2, each with a diameter of 1400µm, are opened at both the top and bottom ends of the black cavity. Two through-hole diagnostic holes 11 are opened on the wall of the black cavity 1 at the equatorial plane. Diagnostic holes 11 are square holes with dimensions of 900µm × 500µm. Shock wave sample 14 and ablation sample 25 are placed in the two diagnostic holes 11, respectively. The cavity wall material of the black cavity 1 is gold (Au), with a thickness of 25~50µm. Both the shock wave sample 14 and the ablation sample 25 placed on the cavity wall of the black cavity 1 are, for example, Al. The shock wave sample 14 is a five-step sample with a base thickness of approximately 60µm and each step thickness of approximately 20µm. The ablation sample 25 is a planar sample with a thickness of approximately 26µm.

[0053] Step 3: Measure the temperature profile of the radiation source inside the cavity through injection port 2 using a flat-response radiation flow detector 9. This is used to determine the temperature-time behavior of the radiation source after a square wave laser (>2ns).

[0054] Step 4: Using a striped radiation pyrometer 6, measure the self-illumination image of the sample from the rear surface of the standard shock wave sample 14 to obtain a shock wave image with time scale (e.g., Figure 3 As shown in the figure, the analysis gives the surface time after the shock wave penetrates the 2nd to 4th steps. , and And the average velocity of the shock wave in the adjacent 2nd-3rd and 3rd-4th steps. and .

[0055] Step 5: Using the local radiation flow measurement system 4, the radiation burn-through energy flow curves in the 100-4000 eV energy range are measured from the back surface of the ablated sample 25; In addition, the burn-through images in two energy ranges (187-215 eV and 510-794 eV) are measured from the back surface of the ablated sample 25 using a three-chromatograph 8, and the radiation burn-through energy flow curves in each energy range are analyzed and given.

[0056] Step 6, Peak temperature of the radiation source 39 points were uniformly sampled within the range of 190–228 eV, and the time evolution factor was... 28 points were uniformly sampled within the range of 0.03-0.3, and a series of radiation source temperature distribution curves over time were generated according to equation (1). These curves served as the input source for the radiation fluid simulation. The one-dimensional radiation fluid program Multi1D was used to simulate and calculate the moment when the shock wave passed through the interface after the third step. and shock wave velocity ( and A one-dimensional simulated dataset.

[0057] Step 7: Based on the simulated dataset, use the Bayesian inversion method to determine the experimentally measured shock wave exit time at the interface. ,speed and The reconstructed sample surface radiation source temperature is obtained by probabilistic matching with a one-dimensional simulation dataset. ,like Figure 4 As shown. The reconstructed radiation source Radiation source measured with injection hole 2 compared to, The rise is faster, and the peak temperature is lower. This difference leads to significant discrepancies in the simulated shock wave exit moment and velocity. (Refer to...) Figure 5 Compared with the experimental results, using The calculated impact exit point was too early and too fast, both outside the error range of the experimental results. However, using the reconstructed... As the input radiation source, the simulation calculations obtained the shock wave exit time and velocity of shock wave sample 14, which were within the experimental error range and consistent with the experimental results. Meanwhile, using... The calculated radiation burn-through energy flux of ablated sample 25 is also consistent with the experimental results, and the radiation source temperature of the surface of the reconstructed sample is accurate.

[0058] This invention innovatively proposes to simultaneously use the moment the shock wave exits the sample interface and the shock wave velocity as key constraint parameters for describing the physical process. By constructing a parameterized Bayesian probability mapping relationship between the radiation temperature and the shock wave, in-situ reconstruction of the temporal evolution history of the radiation source temperature in the ICF black cavity is achieved. Compared with existing methods for reconstructing radiation temperature at the sample, this method has the following advantages: First, compared with traditional methods that only use the shock wave velocity to constrain the physical process, the addition of the constraint of the moment the shock wave exits the sample interface improves the accuracy of the reconstructed radiation temperature; Second, by introducing Bayesian probability analysis, a one-to-one mapping relationship between the parameterized radiation temperature and the shock wave can be quickly established, thus avoiding the problem of traditional methods' strong dependence on the accuracy of multidimensional radiation fluid simulation models and material property parameters, improving the efficiency of the method and reducing the difficulty of implementation. Furthermore, since the iterative process of multidimensional radiation fluid simulation calculation is extremely computationally intensive, the new method can save computational resources.

[0059] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention. Those skilled in the art, under the guidance of the present invention, can make various similar representations without departing from the spirit and claims of the present invention, and such modifications all fall within the protection scope of the present invention.

Claims

1. A method for reconstructing in-situ the time evolution of the temperature of a sample surface irradiated in an ICF hohlraum, characterized in that, The method comprises the following steps: S1, fixing the black cavity (1) at the center of the vacuum target chamber by a special target holder, and providing an injection hole (2) at each end of the black cavity (1); Step S2, using multi-beam laser (3) from the injection hole (2) on the upper and lower ends of the black cavity (1) injection black cavity (1), and produce strong X-ray, form the rising radiation source, using the flat response radiation flow detector (9) from the injection hole (2) measurement black cavity (1) in the radiation source temperature evolution data with time as ; S3, providing two diagnostic holes (11) passing through the equatorial plane of the black cavity (1), one of the diagnostic holes (11) is provided with an impact wave sample 1 (4), and the other is provided with an ablation sample 25 (5), the ablation sample 25 (5) is made of the same material as the impact wave sample 1 (4), the X-ray radiation generated by the black cavity (1) irradiates the surface of the impact wave sample 1 (4) and the ablation sample 25 (5), the X-ray radiation flow forms an impact wave in the impact wave sample 1 (4), the impact wave passes through the rear surface of the impact wave sample 1 (4), the X-ray radiation flow burns through the ablation sample 25 (5), and the radiation flow passes through the rear surface of the ablation sample 25 (5); Step S4, measure the shock breakout time of shock sample 1 (4) using a time resolved shock diagnostics instrument and shock velocity measure the radiation burnthrough flux curve from the back surface of ablation sample 25 (5) using a radiation dosimeter S5, obtaining a radiation source temperature curve model in the form of an exponential function: （1） In the above formula, is the pulse width of the laser, is the peak radiation source temperature, is the radiation source temperature time evolution factor, is the ratio of the radiation source temperature at the sample surface at the peak moment to the radiation source temperature measured by the flat response radiation flow probe (9) and the like at the injection hole (2), is the radiation source temperature of the injection hole (2) measured by the flat response radiation flow probe (9) and the like, giving the radiation source distribution function after the laser ends, and the two together constitute the radiation source temperature distribution function with time in the whole period; by adjusting the radiation source temperature parameters and in formula (1), a series of radiation source temperature distribution curve data are obtained as the input source of the radiation fluid simulation, and using the radiation fluid program, one-dimensional simulation data sets of the time at which the shock wave formed by the interaction of the radiation source and the shock wave sample 1 (4) penetrates the back interface and the shock wave velocity are obtained, and the quantitative mapping relationship between the radiation source temperature parameters and the shock wave characteristic diagnostic quantities is extracted; Step S6, using the Bayesian inversion method, by matching the experimental measured shock wave out of interface time, speed and simulation data set, the radiation source temperature parameter of the incident sample is established and The posterior probability distribution of , , that is, the radiation source temperature of the sample surface; Step S7, reconstructing the sample surface radiant source temperature The reconstructed radiant source temperature is cross-verified by simulating the fluence of the radiation ablation of the sample 25 (5) and comparing it with the experimental measurements.

2. The method of claim 1, wherein the method further comprises: determining the temperature of the sample surface in the ICF hohlraum at a plurality of times during the experiment. In step S1, the black cavity (1) is a column cavity, a spherical cavity or a special-shaped cavity.

3. The method of claim 1, wherein the method further comprises: determining the temperature of the sample surface in the ICF hohlraum at a plurality of times during the irradiation of the sample surface by the laser beam. The base thickness of the shock wave sample 1 (4) greater than The thickness of the ablation sample 25 (5) .

4. The method of claim 1, wherein the method further comprises: determining the temperature of the sample surface in the ICF hohlraum at a plurality of times during the experiment. In step S4, the time-resolved impact wave diagnostic instrument is a streak radiation pyrometer or an arbitrary reflective surface velocity interferometer system.

5. The method of claim 1, wherein the method further comprises: determining the temperature of the sample surface in the ICF hohlraum at a plurality of times during the irradiation of the sample surface by the laser beam. In step S4, the radiation dosimeter comprises a local radiation flow measurement system (7) and a three-color spectrometer (8).

6. The method of claim 1, wherein the method further comprises: The material of the impact wave sample 1 (4) is Al. ​ 7. The method of claim 6, wherein the method further comprises: determining the temperature of the sample surface in the ICF hohlraum at a plurality of times during the irradiation of the sample surface by the laser beam. The impact wave sample 1 (4) is a five-step sample, the base thickness is 60 μm, and the thickness of each step is 20 μm, and the ablation sample 25 (5) is a planar sample with a thickness of 26 μm.

8. The method of claim 1, wherein the method further comprises: determining the temperature of the sample surface in the ICF hohlraum at a plurality of times during the experiment. The laser (3) is a square wave laser.

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