Transmission simulation method of X-ray free electron laser pulse

Abstract

The invention provides an X-ray free electron laser pulse transmission simulation method. The method comprises the steps that a three-dimensional light field of an X-ray free electron laser pulse light field generated through simulation is acquired; according to the type of the X-ray free electron laser pulse, different dimension reduction methods are selected, and a probability density distribution function of the X-ray free electron laser pulse in the six-dimensional phase space is determined; and selecting the random scatter points based on the probability density distribution function corresponding to the X-ray free electron laser pulse, and determining a target light source model of the X-ray free electron laser pulse light field in the six-dimensional phase space so as to evaluate the free electron laser pulse in the beam line. Six-dimensional phase space distribution is reduced to low dimension, six-dimensional phase space scatter points are obtained, transmission simulation of free electron laser pulses in a beam line is further carried out, the calculation speed is higher compared with a wave optics method, and rapid evaluation of transmission of XFEL pulses in the beam line is achieved.

Description

Technical Field

[0001] This application relates to the field of optical technology, and more specifically, to a method for simulating the transmission of X-ray free electron laser pulses. Background Technology

[0002] Free-electron lasers (FELs), as representatives of fourth-generation light sources, possess excellent characteristics such as high brightness, good coherence, and short pulses, and have broad application prospects in physics, chemistry, biology, and other fields. The construction process of an FEL pulsed light source typically involves three key steps: first, simulating the interaction between the electron beam and the radiation field in the undulator by numerically solving differential equations to generate a three-dimensional pulsed light field; second, extracting its six-dimensional phase space distribution information from the three-dimensional light field; and finally, generating scattered points satisfying the six-dimensional phase space intensity distribution using the Monte Carlo method. However, the numerical calculation of the six-dimensional Wigner function involves high-dimensional integrals and a massive amount of data, posing significant challenges to numerical implementation, including high storage requirements and computational complexity. Especially for coherent X-ray sources like FELs with high brightness characteristics, their light field distribution often exhibits complex spatial structures and temporal evolution characteristics, making the numerical calculation of six-dimensional phase space reconstruction even more difficult. Summary of the Invention

[0003] The purpose of this application is to provide a method for simulating the transmission of X-ray free electron laser pulses, in order to solve the technical problems of large computational load and slow computational efficiency in the existing FEL pulse source simulation process.

[0004] In a first aspect, the present invention provides a method for simulating the transmission of X-ray free-electron laser pulses. The method includes acquiring the three-dimensional light field of the simulated X-ray free-electron laser pulse light field; selecting different dimensionality reduction methods according to the type of X-ray free-electron laser pulse to determine the probability density distribution function of the X-ray free-electron laser pulse in a six-dimensional phase space; and discarding random scattered points based on the probability density distribution function corresponding to the X-ray free-electron laser pulse to determine the target light source model of the X-ray free-electron laser pulse light field in a six-dimensional phase space, so as to evaluate the free-electron laser pulse in the beamline.

[0005] In an optional implementation, when the X-ray free-electron laser pulse is a chirped X-ray free-electron laser pulse and the X-ray free-electron laser pulse is located at the source point, the probability density distribution function of the X-ray free-electron laser pulse in the six-dimensional phase space is determined by the following method. , : ; ; in, X-ray free electron laser pulses in a three-dimensional light field Intensity distribution of the domain, For X-ray free electron laser pulses in a three-dimensional light field ( Intensity distribution of the domain.

[0006] In an optional implementation, the following methods are used to determine : ; ;

[0007] ; in, The three-dimensional optical field of an X-ray free-electron laser pulse. denoted as the wavenumber corresponding to different frequency light fields.

[0008] In an optional implementation, when the X-ray free-electron laser pulse is a chirped or defocused three-dimensional pulse, the probability density distribution function of the X-ray free-electron laser pulse in the six-dimensional phase space is determined by the following method: The three-dimensional light field of X-ray free electron laser pulses is obtained by using singular value decomposition algorithm. Decomposed into a one-dimensional light field With two-dimensional light field The product; The two-dimensional light field of X-ray free electron laser pulses is obtained by using the singular value decomposition algorithm. Decomposed into a one-dimensional light field With one-dimensional light field The product; For one-dimensional light field , , The corresponding Wigner phase space distributions were determined respectively. , , In order to calculate the corresponding probability density distribution function.

[0009] In an optional implementation, the distribution of the X-ray free-electron laser pulse field in the six-dimensional phase space is determined by the following method. : .

[0010] In an optional implementation, the propagation path of the beam line through the optical element is traced in six-dimensional phase space using a target light source model of the X-ray free electron laser pulse light field in six-dimensional phase space; when the optical element is a slit, the method further includes wave optics calculation based on the distribution of the X-ray free electron laser pulse light field, so as to correct the tracing result in six-dimensional phase space according to the wave transmission result.

[0011] In an optional implementation, selection is made in the following manner: The target range is determined based on the curve of the probability density distribution function; Randomly generate scattered points within the target area; Retain the points that lie below the curve of the probability density distribution function.

[0012] Secondly, the present invention provides a transmission simulation device for X-ray free electron laser pulses, the device comprising: The acquisition module is used to acquire the three-dimensional light field of the simulated X-ray free electron laser pulse light field; The dimension reduction module is used to select different dimension reduction methods based on the type of X-ray free electron laser pulse to determine the probability density distribution function of the X-ray free electron laser pulse in the six-dimensional phase space. The selection module is used to select random points based on the probability density distribution function corresponding to the X-ray free electron laser pulse, and determine the target source model of the X-ray free electron laser pulse light field in six-dimensional phase space, so as to evaluate the free electron laser pulse in the beamline.

[0013] Thirdly, the present invention provides an electronic device, comprising: a processor, a memory, and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor communicates with the memory via the bus, and the processor executes the machine-readable instructions to perform the steps of the X-ray free electron laser pulse transmission simulation method as described in any of the foregoing embodiments.

[0014] Fourthly, the present invention provides a computer-readable storage medium storing a computer program, wherein the computer program, when executed by a processor, performs the steps of the X-ray free electron laser pulse transmission simulation method as described in any of the foregoing embodiments.

[0015] This application provides a method for simulating the propagation of X-ray free-electron laser pulses. The method includes acquiring the three-dimensional optical field of the simulated X-ray free-electron laser pulse; selecting different dimensionality reduction methods according to the type of X-ray free-electron laser pulse to determine the probability density distribution function of the X-ray free-electron laser pulse in a six-dimensional phase space; and discarding random points based on the probability density distribution function corresponding to the X-ray free-electron laser pulse to determine the target source model of the X-ray free-electron laser pulse optical field in the six-dimensional phase space for evaluation of the free-electron laser pulse. By reducing the six-dimensional phase space distribution to a lower dimension, six-dimensional phase space scatter points are obtained, and then the propagation simulation of the free-electron laser pulse in the beamline is performed. This method is faster than wave optics methods and enables rapid evaluation of XFEL beamlines. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A flowchart illustrating the steps of a simulation method for the transmission of an X-ray free-electron laser pulse, provided for an embodiment of this application; Figure 2 A schematic diagram of a probability distribution provided for an embodiment of this application; Figure 3 A schematic diagram of the structure of a simulation device for the transmission of X-ray free electron laser pulses provided in this application embodiment; Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application; Figure 5(a) is a schematic diagram of six-dimensional phase space tracing of a beamline when it passes through a reflector, provided in an embodiment of this application. Figure 5(b) is a schematic diagram of six-dimensional phase space tracing of a beamline when it passes through a grating, according to an embodiment of this application. Figure 5(c) is a schematic diagram of six-dimensional phase space tracing of a beamline when it passes through free space, provided in an embodiment of this application. Figure 5(d) is a schematic diagram of six-dimensional phase space tracing of a beamline when it passes through a slit, according to an embodiment of this application. Figure 6 This is a schematic diagram of the projection of a diffraction-corrected beamline provided in an embodiment of this application. Detailed Implementation

[0018] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0019] Example 1 Figure 1 A flowchart illustrating the steps of a simulation method for the transmission of an X-ray free-electron laser pulse, provided in an embodiment of this application. Figure 1 As shown, in one embodiment of this application, a method for simulating the transmission of an X-ray free-electron laser pulse is provided, the method comprising: S1. Obtain the three-dimensional light field of the simulated X-ray free electron laser pulse light field.

[0020] In step S1, the three-dimensional optical field at the saturation point or undulator exit position can be generated using the existing software GENESIS 1.3. The interaction between the electron beam and the radiated optical field in the undulator can be simulated by numerically solving differential equations to determine the simulation parameters.

[0021] In a specific example, the simulation parameters input to GENESIS can be as shown in Table 1 below.

[0022] Table 1

[0023] The simulated three-dimensional light field here can be stored as a... In the three-dimensional matrix of sampling points, where, and Represents the horizontal coordinate The number of sampling points, Represents the vertical coordinate The number of sampling points.

[0024] Furthermore, the distribution of the X-ray free-electron laser pulse field in six-dimensional phase space can be determined in the following way. : .

[0025] Theoretically, it is possible to base it on the Wigner six-dimensional phase space light intensity distribution. (As a probability density distribution) generates light rays Scattered points. However, the numerical computation of six-dimensional functions is large, so it is necessary to reduce the computational load.

[0026] S2. Based on the type of X-ray free electron laser pulse, different dimensionality reduction methods are selected to determine the probability density distribution function of the X-ray free electron laser pulse in the six-dimensional phase space.

[0027] In one feasible embodiment, dimensionality reduction can be performed using a projection method. When the X-ray free electron laser pulse is a non-chirped X-ray free electron laser pulse and is located at the source point, the probability density distribution function of the X-ray free electron laser pulse in the six-dimensional phase space can be determined as follows: , : ; ; in, Let X represent the intensity distribution of an X-ray free-electron laser pulse in the (x,y,t) domain within a three-dimensional optical field. For X-ray free electron laser pulses in a three-dimensional light field ( Intensity distribution of the domain.

[0028] Specifically, it can be determined in the following ways. : ; ;

[0029] ; in, The three-dimensional optical field of an X-ray free-electron laser pulse. denoted as the wavenumber corresponding to different frequency light fields.

[0030] The XFEL three-dimensional light field is converted into scattered points, and the distribution of light intensity corresponds to the probability density of the scattered points.

[0031] In another feasible embodiment, principal component analysis is also provided for dimensionality reduction, which is suitable for... When the dimensional coupling is relatively low, it can be applied to chirped and defocused 3D pulses.

[0032] Specifically, when the X-ray free electron laser pulse is a chirped or defocused X-ray free electron laser pulse, the probability density distribution function of the X-ray free electron laser pulse in the six-dimensional phase space can be determined in the following way: The three-dimensional light field of X-ray free electron laser pulses is obtained by using singular value decomposition algorithm. Decomposed into a one-dimensional light field With two-dimensional light field The product; The two-dimensional light field of X-ray free electron laser pulses is obtained by using the singular value decomposition algorithm. Decomposed into a one-dimensional light field With one-dimensional light field The product; For one-dimensional light field , , The corresponding Wigner phase space distributions were determined respectively. , , In order to calculate the corresponding probability density distribution function.

[0033] Principal component analysis is performed on the three-dimensional light field, and the principal components are obtained using the singular value decomposition method. If the energy percentage of the principal component is close to 1, then The three dimensions can be approximated as decoupling. We can then obtain: ; From the scene Obtain the Wigner phase space The scatter points were obtained using a two-dimensional discarding method. Similarly, dimension values ​​can also be obtained through... and Scatter points were obtained respectively and Dimension value.

[0034] Specifically, this can be achieved through singular value decomposition (SVD) of the three-dimensional light field. The corresponding three-dimensional matrix First convert it into OK, The two-dimensional matrix of columns is then decomposed into singular value matrices. ,in, Given a diagonal matrix, if the first row and first column of this matrix are significantly larger than the other matrix elements, then the principal modulus of the matrix corresponding to the first row and first column is: ; If the diagonal matrix The diagonal elements are respectively , ... The energy percentage of the main mode is: ; If the ratio is close to 1, such as 99%, then we can conclude that... .

[0035] In another feasible embodiment, a hybrid approach combining projection and singular decomposition is also provided for dimensionality reduction. Specifically, principal component analysis can be used to analyze the strength of coupling between the six dimensions, such as principal components. If the percentage is close to 1, then... Project to , , , The selection of spaces is handled using a discarding method.

[0036] Principal component analysis shows that if the proportion of the principal modulus component is close to 1, then... ,Right now and Dimensional decoupling, i.e. and Dimensional independence, through calculate , right Perform singular value decomposition, if and If the dimensions are independent, then the projection intensity is used. , Calculate the probability density: ; .

[0037] S3. Based on the probability density distribution function corresponding to the X-ray free electron laser pulse, random scattered points are discarded to determine the target source model of the X-ray free electron laser pulse light field in the six-dimensional phase space, so as to evaluate the free electron laser pulse in the beamline.

[0038] In step S3, scatter points conforming to the probability distribution can be generated based on the Wigner function, specifically using the discarding method in the Monte Carlo method. Specifically, discarding can be performed in the following way: The target range is determined based on the probability density function curve, and scattered points are randomly generated within the target range. Points located below the probability density function curve are retained.

[0039] Figure 2 This is a schematic diagram of a probability distribution provided for an embodiment of this application. For example... Figure 2 As shown in the figure, the curve represents the probability distribution corresponding to the Wigner function. Randomly scattering points within the rectangular area of ​​the figure, selecting points below the curve and discarding those above, leaves points that satisfy the probability distribution. When the dimensions of the probability distribution function are independent, a one-dimensional function rejection method is used. When there is coupling between two dimensions, a two-dimensional function rejection method is used, such as in chirped pulsed light. When the pulse has spatiotemporal coupling, a three-dimensional or even higher-dimensional function rejection method is required.

[0040] Example 2 In one embodiment of this application, a diffraction correction method for six-dimensional phase space geometric tracing is provided.

[0041] The scattered pulses generated by the light source model can be geometrically traced to obtain scattered pulses at different positions of the beamline. When passing through the slit of the diffractive optical element, the scattered pulses need to be corrected. Specifically, the propagation path of the beamline through the optical element can be traced in six-dimensional phase space using a target light source model of the X-ray free electron laser pulse light field in six-dimensional phase space.

[0042] The traditional four-dimensional phase space ray vector is Propagating in a straight line in free space, its propagation direction changes after passing through mirrors and gratings. As shown in Figures 5(a)-(d), after phase-space tracing by optical elements, except for lateral information... Vertical information This means that the frequency of light is the same before and after propagation, i.e. The time it takes for light to travel is the input time plus the time difference, where the time difference is the optical path difference divided by the speed of light. The optical path difference is the distance traveled by each ray minus the distance traveled by the rays along the principal optical axis, i.e. .

[0043] When the optical element is a slit, it also includes wave optics calculation based on the X-ray free electron laser pulse light field distribution, so as to correct the tracking result in the six-dimensional phase space according to the wave transmission result.

[0044] The simulation method described in the aforementioned embodiment, being based on geometric optics principles, generates diffraction when optical elements such as slits are present along the beamline. To describe this diffraction phenomenon, a diffraction correction method is employed. First, the Wigner phase space distribution... Estimating the light field distribution The distribution is then analyzed, followed by wave optics calculations, and corrections are made based on the wave propagation results. distributed.

[0045] For example, when the pulsed light passes through the slit at the focusing position of the grating, The scatter points of direction are filtered out. Light spot size in the direction It becomes smaller, according to the diffraction limit relationship divergence angle As a result, it increases. At this point, we assume the light field distribution... The light field was calculated using the Fourier transform method. The far-field angular distribution is then expanded into multiple rays, with each ray centered on its initial direction. The far-field angular distribution is a probability density distribution that is randomly shifted.

[0046] In six-dimensional phase space tracing, the diffraction-limiting relation also includes When the grating slit size decreases, The bandwidth of the pulse remains unchanged. It will decrease, assuming The corresponding frequency domain distribution is calculated using Fourier transform. The original value of light. With the center point, As a probability density distribution, a single ray is expanded into multiple rays. For example... Figure 6 As shown, Figure 6 This is a schematic diagram of the projection of a diffraction-corrected beamline provided in an embodiment of this application.

[0047] Example 3 Figure 3 This is a schematic diagram of the structure of a simulation device for the transmission of X-ray free electron laser pulses provided in an embodiment of this application. Figure 3 As shown, based on the same inventive concept, this application also provides an X-ray free electron laser pulse transmission simulation device 30, the device comprising: The acquisition module 310 is used to acquire the three-dimensional light field of the simulated X-ray free electron laser pulse light field; The dimension reduction module 320 is used to select different dimension reduction methods according to the type of X-ray free electron laser pulse and determine the probability density distribution function of the X-ray free electron laser pulse in the six-dimensional phase space. The selection module 330 is used to select random scattered points based on the probability density distribution function corresponding to the X-ray free electron laser pulse, and determine the target source model of the X-ray free electron laser pulse light field in the six-dimensional phase space for evaluation of the free electron laser pulse.

[0048] In a preferred embodiment, when the X-ray free-electron laser pulse is a chirped X-ray free-electron laser pulse and the X-ray free-electron laser pulse is located at the source point, the probability density distribution function of the X-ray free-electron laser pulse in the six-dimensional phase space is determined by the following method. , : ; ; in, The intensity distribution of an X-ray free-electron laser pulse in the time domain within a three-dimensional optical field. This represents the frequency domain intensity distribution of an X-ray free-electron laser pulse in a three-dimensional optical field.

[0049] In a preferred embodiment, the following method is used to determine : ; ;

[0050] ; in, The three-dimensional optical field of an X-ray free-electron laser pulse. denoted as the wavenumber corresponding to different frequency light fields.

[0051] In a preferred embodiment, when the X-ray free-electron laser pulse is a chirped X-ray free-electron laser pulse or a three-dimensional pulse at a defocus position, the probability density distribution function of the X-ray free-electron laser pulse in the six-dimensional phase space is determined by the following method: The three-dimensional light field of X-ray free electron laser pulses is obtained by using singular value decomposition algorithm. Decomposed into a one-dimensional light field With two-dimensional light field The product; The two-dimensional light field of X-ray free electron laser pulses is obtained by using the singular value decomposition algorithm. Decomposed into a one-dimensional light field With one-dimensional light field The product; For one-dimensional light field , , The corresponding Wigner phase space distributions were determined respectively. , , In order to calculate the corresponding probability density distribution function.

[0052] In a preferred embodiment, the distribution of the X-ray free-electron laser pulse field in the six-dimensional phase space is determined by the following method. : .

[0053] In a preferred embodiment, the distribution of the X-ray free electron laser pulse light field is estimated using a target light source model of the X-ray free electron laser pulse light field in six-dimensional phase space.

[0054] In a preferred embodiment, wave optics calculations are performed based on the X-ray free electron laser pulse light field distribution to correct the distribution in the six-dimensional phase space according to the wave propagation results.

[0055] In a preferred embodiment, selection is performed in the following manner: The target range is determined based on the curve of the probability density distribution function; Randomly generate scattered points within the target area; Retain the points that lie below the curve of the probability density distribution function.

[0056] Example 4 Please see Figure 4 , Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 4 As shown, the electronic device 400 includes a processor 410, a memory 420, and a bus 430.

[0057] The memory 420 stores machine-readable instructions that can be executed by the processor 410. When the electronic device 400 is running, the processor 410 and the memory 420 communicate via the bus 430. When the machine-readable instructions are executed by the processor 410, the steps of a transmission simulation method for an X-ray free electron laser pulse as described in the above method embodiment can be executed. For specific implementation details, please refer to the method embodiment, which will not be repeated here.

[0058] This application also provides a computer-readable storage medium storing a computer program. When the computer program is run by a processor, it can execute the steps of a transmission simulation method for an X-ray free electron laser pulse as described in the above method embodiments. For specific implementation details, please refer to the method embodiments, which will not be repeated here.

[0059] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0060] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0061] Furthermore, the units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0062] Furthermore, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0063] It should be noted that if the function is implemented as a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0064] In this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, without necessarily requiring or implying any such actual relationship or order between these entities or operations.

[0065] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for simulating the transmission of X-ray free-electron laser pulses, characterized in that, The method includes: Obtain the three-dimensional optical field of the simulated X-ray free electron laser pulse light field; Based on the type of X-ray free electron laser pulse, different dimensionality reduction methods are selected to determine the probability density distribution function of the X-ray free electron laser pulse in the six-dimensional phase space; By discarding random scattered points based on the probability density distribution function corresponding to the X-ray free electron laser pulse, the target source model of the X-ray free electron laser pulse light field in the six-dimensional phase space is determined, so as to evaluate the free electron laser pulse in the beamline.

2. The method according to claim 1, characterized in that, When the X-ray free electron laser pulse is a non-chirped X-ray free electron laser pulse and is located at the source point, the probability density distribution function of the X-ray free electron laser pulse in the six-dimensional phase space is determined by the following method. , : ； ； in, X-ray free electron laser pulses in a three-dimensional light field Intensity distribution of the domain, For X-ray free electron laser pulses in a three-dimensional light field ( Intensity distribution of the domain.

3. The method according to claim 2, characterized in that, Determined in the following ways : ； ； ； in, The three-dimensional optical field of an X-ray free-electron laser pulse. denoted as the wavenumber corresponding to different frequency light fields.

4. The method according to claim 1, characterized in that, When the X-ray free electron laser pulse is a chirped or defocused X-ray free electron laser pulse, the probability density distribution function of the X-ray free electron laser pulse in the six-dimensional phase space is determined by the following method: The three-dimensional light field of X-ray free electron laser pulses is obtained by using singular value decomposition algorithm. Decomposed into a one-dimensional light field With two-dimensional light field The product; The two-dimensional light field of X-ray free electron laser pulses is obtained by using the singular value decomposition algorithm. Decomposed into a one-dimensional light field With one-dimensional light field The product; For one-dimensional light field , , The corresponding Wigner phase space distributions were determined respectively. , , In order to calculate the corresponding probability density distribution function.

5. The method according to claim 1, characterized in that, The distribution of the X-ray free-electron laser pulse field in six-dimensional phase space was determined by the following method. : 。 6. The method according to claim 1, characterized in that, Using a target light source model of X-ray free-electron laser pulses in six-dimensional phase space, the propagation path of the beam line through optical elements is traced in six-dimensional phase space; When the optical element is a slit, it also includes wave optics calculation based on the X-ray free electron laser pulse light field distribution, so as to correct the tracking result in the six-dimensional phase space according to the wave transmission result.

7. The method according to claim 1, characterized in that, The following methods can be used to discard selections: The target range is determined based on the curve of the probability density distribution function; Randomly generate scattered points within the target area; Retain the points that lie below the curve of the probability density distribution function.

8. A simulation device for the transmission of X-ray free-electron laser pulses, characterized in that, The device includes: The acquisition module is used to acquire the three-dimensional light field of the simulated X-ray free electron laser pulse light field; The dimension reduction module is used to select different dimension reduction methods based on the type of X-ray free electron laser pulse to determine the probability density distribution function of the X-ray free electron laser pulse in the six-dimensional phase space. The selection module is used to select random points based on the probability density distribution function corresponding to the X-ray free electron laser pulse, and determine the target source model of the X-ray free electron laser pulse light field in six-dimensional phase space, so as to evaluate the free electron laser pulse in the beamline.

9. An electronic device, characterized in that, include: The device includes a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor communicates with the memory via the bus, and the processor executes the machine-readable instructions to perform the steps of the X-ray free electron laser pulse transmission simulation method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, performs the steps of the X-ray free electron laser pulse transmission simulation method as described in any one of claims 1 to 7.

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