25 results about "Free-electron laser" patented technology

The invention provides a sample positioning method suitable for an X-ray free electron laser monopulse experiment, and relates to the field of X-ray free electron laser experiments. The method comprises the following steps: step 1), acquiring an initial sample image of a sample to be detected; step 2), processing the initial sample image to obtain a target sample image; 3) identifying the contour of the target sample in the target sample image, and obtaining the pixel coordinates of the target sample; 4) performing visual proportion calibration on the target sample image to obtain a visual proportion coefficient; 5, based on the visual proportionality coefficient and the pixel coordinates of the target sample, the positioning coordinates of the target sample on the experimental platform are calculated in combination with datum point information.According to the method, accurate coordinate mapping and positioning can be achieved, the experimental performance is improved, and automation of the experimental process is promoted.

The invention discloses an integrated free electron laser on-line collimation and visible indication laser system and method, and the system employs a theoretical center line representing a magnetic axis of an undulator as a reference, and a collimation system completes the coincidence collimation of an electron beam axis and an optical axis with the theoretical center line; the visible light indication system provides a reference visible light beam for downstream beam line commissioning, where the reference visible light beam coincides with the theoretical centerline, and the system can be independently commissioned out of vacuum. The collimation system and the visible light indication system are mutually independent, are coupled through the upstream reflector and the downstream reflector, do not influence each other, and can be permanently used on line.

The present application provides a fixed-target sample scanning method and system based on an X-ray free electron laser. The method comprises: acquiring a fixed target sample image of an X-ray free electron laser; performing sample identification on the basis of the fixed target sample image to obtain an identified sample image; acquiring a pulse point of the X-ray free electron laser, and sorting sample coordinates in the identified sample image on the basis of coordinates of the pulse point, to determine a scanning path of a fixed target sample; and performing fixed-point scanning on the fixed target sample on the basis of the scanning path. The present application realizes the identification and fixed-point scanning of a fixed target sample of an X-ray free electron laser, thereby improving the utilization rate, and further improving the experimental efficiency and the quality of data.

The application relates to a liquid sheet injection system and method for X-ray free electron laser experiments, which comprises a pneumatic nozzle device, a flow control device, a signal acquisition device and a vacuum device; the pneumatic nozzle device and the signal acquisition device are respectively arranged in the vacuum device, the pneumatic nozzle device comprises a tube assembly, a gas capillary and a liquid capillary are respectively arranged in the tube assembly, and the gas capillary and the liquid capillary are connected with the flow control device; the end of the liquid capillary comprises two symmetrically arranged flow guide inclined surfaces, two symmetrically arranged abutting inclined surfaces and a bottom surface, the flow guide inclined surfaces and the abutting inclined surfaces are alternately distributed around the bottom surface, and a first outlet is arranged on the bottom surface; a gas micro-flow channel is formed between the end inner wall of the tube assembly and the flow guide inclined surface, and a second outlet is arranged at the end of the tube assembly. The application utilizes the compression and shearing effect of high-speed gas on liquid to generate a free-flowing liquid sheet with a sub-micron thickness under vacuum.

The invention provides an adjustable tapering undulator and device based on beat frequency superposition and a method for broadening a spectrum, and is applied to the technical field of synchrotron radiation and the technical field of free electron laser. The undulator comprises a first magnetic array structure which comprises a plurality of groups of first permanent magnet units and is used for generating a first magnetic field; the second magnetic array structure comprises a plurality of groups of second permanent magnet units and is used for generating a second magnetic field; the phase shift driving structure is used for responding to a target superposed magnetic field after the beat frequency superposition of the first magnetic field and the second magnetic field, and determining the beat frequency magnetic period length of the target superposed magnetic field according to the first magnetic period length and the second magnetic period length; and according to the tapering requirement of the undulator, determining a target phase shift from a target beat frequency envelope constructed based on the attribute parameters of the adjustable tapering undulator and the beat frequency magnetic period length, and driving the phase shift driving structure to enable the first magnetic array structure and / or the second magnetic array structure to translate along the advancing direction of the electron beam.

The application discloses an ultrathin diamond clamping device, which comprises, from top to bottom, a graphite pressing block, a polycrystalline diamond limiting sheet, a polycrystalline diamond bottom sheet, a graphite bottom plate and graphite screws for fixing the above-mentioned elements; the polycrystalline diamond limiting sheet is provided with at least one rectangular notch, and the limiting groove for positioning the ultrathin diamond crystal sheet is formed by the rectangular notch and the polycrystalline diamond bottom sheet; the graphite pressing block covers the ultrathin diamond crystal sheet, the graphite screws pass through the graphite pressing block, the polycrystalline diamond limiting sheet and the polycrystalline diamond bottom sheet in sequence and are connected with the graphite bottom plate, the graphite pressing block is extruded by twisting the graphite screws, pressure is applied to the ultrathin diamond crystal sheet to realize clamping. According to the application, the ultrathin diamond clamping device has the advantages of low thermal load, small clamping stress, small radiation damage and the like, reliably supports the stable and efficient generation of the seed laser by the monochromator, and finally helps to realize the high-stability operation of the fully-coherent free electron laser.

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.

This invention relates to an X-ray free-electron laser shutter system, comprising a vacuum chamber. The vacuum chamber has an entrance flange on its front side and an exit flange on its rear side. The light beam enters the vacuum chamber through the entrance flange and exits outwards through the exit flange. The key feature is that the vacuum chamber is equipped with a front light-blocking arm and a rear light-blocking arm. Another technical solution of this invention provides a control method for the X-ray free-electron laser shutter system. This invention achieves both damage resistance and radiation blocking by combining a damage-resistant light-blocking plate with a heavy metal light-blocking plate. The easily removable damage-resistant light-blocking plate acknowledges its potential for damage and utilizes its working lifespan to achieve light blocking. An interlocking mechanism that burns through the detector ensures that the shutter will not damage downstream equipment due to failure. The use of dual light-blocking arms and an electromagnet to control the on / off time difference between the two light-blocking arms achieves a millisecond-level window time, greatly reducing the requirements for light-blocking arm movement control.

The present application relates to the technical field of precision adjustment device of free electron laser accelerator, especially to a displacement table limiting device. The displacement table limiting device comprises a pitch angle limiting component, a yaw angle limiting component and a displacement limiting component. The pitch angle limiting component, the yaw angle limiting component and the displacement limiting component are arranged to independently undertake the functions of pitch angle over-limit limiting triggering, yaw angle over-limit limiting triggering and horizontal and vertical displacement over-limit limiting triggering, so that the angle limiting and the displacement limiting are independent of each other in function and do not interfere with each other, the decoupling of the angle limiting and the displacement limiting is realized, the accuracy and reliability of the limiting are improved, and the collision of the focusing coil and its support seat with the surrounding equipment due to excessive movement can be effectively prevented, and the safety of the equipment is ensured.

The invention relates to a small-signal free radical infrared spectrum detection method. The method comprises the following steps: 1, acting photolysis laser on a precursor molecular beam source to obtain a free radical and precursor mixed beam source; 2, infrared laser and free electron laser act on the free radical and precursor mixed beam source to obtain a semi-excitation mixed ion beam source; 3, after the semi-excitation mixed ion beam source passes through an accelerator, a flight time difference T is formed between precursor ions and free ions in the semi-excitation mixed ion beam source; 4, the ion beam source enters a deflection electric field, a first electrode of the deflection electric field applies a voltage pulse signal set according to the flight time difference T, precursor ions deflect, move and are discharged when the voltage pulse signal exists, and the ion beam source enters a detector after passing through a reflector when the voltage pulse signal does not exist. Deflection, movement and discharge of precursor ions are realized in the deflection electric field, free radical ion signals can be increased, and measurement of small-signal free radical infrared spectrum is realized.

The application discloses a light source device, a system and a water window band full-coherent free electron laser generating method. The device comprises: a harmonic generation unit for connecting an electron beam and a seed laser and generating low-order harmonics; at least two cascaded amplifier units connected with the harmonic generation unit, for connecting the low-order harmonic radiation and generating coherent harmonic radiation, and for tuning the coherent harmonic laser to high-order harmonic radiation to obtain water window band full-coherent free electron laser pulses. The application constructs a multi-stage amplifier unit in the rear stage of the harmonic generation unit, and each subsequent amplifier unit is configured to resonate on a high-order harmonic of the radiation output by the previous amplifier unit, so that the harmonic radiation of the previous stage is used as the effective seed of the subsequent stage, the frequency is up-converted stage by stage, the frequency of the coherent radiation is converted to the target high-order harmonic stage by stage, and the water window band full-coherent free electron laser is obtained.

The invention provides a device for realizing single pulse absorption spectrum measurement by using free electron laser, and relates to the technical field of spectral analysis. The device comprises an XFEL light source, a pumping laser light source, a sample table and a delay table, the XFEL light source is used for emitting XFEL, the pumping laser light source is used for emitting pumping laser, and the delay table is arranged in a light path of the pumping laser; a front monopulse spectrometer, a rear monopulse spectrometer and a time diagnosis mechanism are sequentially arranged in a light path of the XFEL along the propagation direction of the XFEL, and a sample is positioned in the light path of the XFEL and the pumping laser. According to the invention, high-precision spectral measurement under single pulse of XFEL can be realized, the absorption spectrum of the sample to be measured can be accurately calculated, and the problem of instability of spectrum, intensity and position of each pulse of XFEL is solved. Meanwhile, by recording the data of each single pulse of the XFEL, the influence caused by instability is eliminated, and high-precision spectral measurement is realized.

The invention provides a compression storage method for high-repetition-frequency free electron laser diffraction imaging data, and relates to the crossing field of data compression storage and high-energy physical experiment technologies. The method comprises the following steps: 1) reading a data set from an original diffraction image, and uniformly converting the data set into an integer type; 2) determining the size parameter of the diffraction image; 3) traversing effective photon events in each frame of diffraction image, converting two-dimensional coordinates of the effective photon events into one-dimensional coordinates, storing the one-dimensional coordinates, and then, if the photon events are multi-photon events, independently storing pixel values of the multi-photon events; and 4) writing the data of the effective photon events compressed in the step 3) into a file according to a fixed sequence. Zero value pixel storage without signals can be eliminated, only the number, coordinates and counting information of the effective photon events are reserved in the compression process, zero value pixel storage without signals is eliminated, and the data volume is remarkably reduced.

The invention discloses an ultrathin diamond clamping device which comprises a graphite pressing block, a polycrystalline diamond limiting piece, a polycrystalline diamond bottom piece and a graphite bottom plate which are sequentially arranged from top to bottom, and graphite screws used for fixing the elements. At least one rectangular notch is formed in the polycrystalline diamond limiting piece, and a limiting groove used for positioning the ultrathin diamond crystal piece is defined by the rectangular notch and the polycrystalline diamond bottom piece; the graphite pressing block covers the ultra-thin diamond crystal wafer, the graphite screw sequentially penetrates through the graphite pressing block, the polycrystalline diamond limiting piece and the polycrystalline diamond bottom piece and then is connected with the graphite bottom plate in a matched mode, the graphite pressing block is extruded by twisting the graphite screw, and pressure is applied to the ultra-thin diamond crystal wafer so that clamping can be achieved. According to the invention, the device has the advantages of low thermal load, small clamping stress, small radiation damage and the like, provides reliable support for a monochromator to stably and efficiently generate self-seed laser, and finally assists in realizing high-stability operation of full-coherent free electron laser.

The invention relates to a free electron laser, a light source device and a photoetching machine system. The free electron laser comprises a resonant cavity; a first undulator group, the first undulator group is arranged in a manner that an emergent light path is located on a resonant light path of the resonant cavity, the first undulator group is configured to interact with an electron beam to generate modulated light radiation, and the modulated light radiation is configured to modulate the electron beam; and a second undulator group, the second undulator group being arranged such that its emergent light path is located outside the resonant light path of the resonant cavity, the second undulator group being located downstream of the first undulator group, and the second undulator group being configured to interact with the modulated electron beam to generate target optical radiation.

The invention discloses tail field equipment, and relates to the technical field of particle acceleration, the tail field equipment is used for regulating and diagnosing free electron laser beam flow, and the tail field equipment comprises a vacuum chamber which extends along the beam flow direction and is used for providing a vacuum environment; the inner beam assembly is arranged in the vacuum chamber, the inner beam assembly comprises four groups of corrugated beams which are uniformly distributed in the circumferential direction of the vacuum chamber, the four groups of corrugated beams are symmetrically arranged relative to the center of the axis of the beam, a gap between every two adjacent corrugated beams extends in the radial direction of the vacuum chamber, and the four groups of corrugated beams define a beam channel through which the beam passes; the vacuum chamber is fixedly arranged on the supporting structure; the transmission structure is arranged on the supporting structure, each folded beam is at least provided with a hanging rod, and the transmission structure is in driving connection with the hanging rods so as to drive the four sets of folded beams to synchronously move in the radial direction, and then the distance between the four sets of folded beams is adjusted. According to the technical scheme, the tail field intensity of the tail field equipment is convenient to adjust.

The application relates to a seed laser focusing and delaying device and method of a free electron laser, the free electron laser comprising an electron beam generating device, a first modulation section, a first dispersion section, a second modulation section, a second dispersion section and a radiation section, the seed laser focusing and delaying device being integrated in a vacuum chamber of the first dispersion section, the seed laser focusing and delaying device comprising a delay plate, a first lens and a second lens, the delay plate being used for time matching of an optical delay amount of the seed laser and an electron beam delay amount of the first dispersion section, and the first lens and the second lens being used for spatial matching of the seed laser and the electron beam in the second modulation section.

The application discloses an infrared free electron laser cavity system, which comprises a support mechanism, a vacuum chamber, a vacuum pump, a mirror frame mechanism, a mirror changing mechanism and a fine adjustment mechanism; the vacuum chamber is installed on the support mechanism, the vacuum pump is installed on the vacuum chamber and communicates with the vacuum chamber; the fine adjustment mechanism is installed on the support mechanism, and the mirror changing mechanism is installed on the fine adjustment mechanism; the mirror frame mechanism is installed in the vacuum chamber, and both ends of the mirror frame mechanism are connected with the mirror changing mechanism after extending out of the vacuum chamber. The mirror changing mechanism and the fine adjustment mechanism are arranged outside the vacuum chamber, so that the size of the vacuum chamber is reduced, the structure of the vacuum chamber is simplified, and the overall layout of the oscillator is facilitated. Meanwhile, the fine adjustment mechanism can be separated from the heavy vacuum chamber system, cost is reduced, precision is improved, and higher reliability is obtained.

This invention provides a beam positioning system and method for X-ray free electron lasers based on visible light lasers. This invention uses visible light lasers to directly indicate the beam direction instead of XFELs, reducing the radiation risk associated with direct beam adjustment using XFELs. It can be used for beam adjustment in an atmospheric environment and is easy to operate. Through the combination of various components, it can work stably on the beamline station for a long time, effectively improving the optical path adjustment efficiency of XFEL experiments.

A light source includes a linear accelerator for accelerating an electron bunch to a relativistic energy. The light source further includes a first grating, downstream of the linear accelerator and arranged such that the electron bunch is transmitted through the grating to produce a diffraction pattern. The light source further includes an emittance exchange device, downstream of the first grating, that rotates the diffraction pattern to a direction substantially parallel to a direction of propagation of the electron bunch. The light source further includes a laser that produces a pulse of light. The light source is configured such that the pulse of light from the laser interacts with the electron bunch in an overtaking geometry at an interaction point, downstream of the emittance exchange device, while the diffraction pattern is substantially parallel to the direction of propagation of the electron bunch to produce light via inverse Compton scattering.

The application relates to the technical field of large scientific devices, and discloses a plasma attenuator for a high-repetition-frequency soft X-ray free electron laser, which comprises a vacuum pipeline, a plasma source and two annular superconducting magnet systems, the vacuum pipeline is used for passing the soft X-ray free electron laser; the plasma source is arranged on the vacuum pipeline; the two superconducting magnet systems are sleeved on the vacuum pipeline and coaxially arranged and used for providing an axial magnetic field; the two superconducting magnet systems are respectively arranged on the two sides of the plasma source and form a plasma window to constrain the plasma in the vacuum pipeline. By adopting the pre-ionized and magnetically confined plasma as an absorption medium, the traditional neutral gas attenuation scheme is replaced, the nonlinear effects such as density hole and beam filamentation which are easily generated in the attenuation process of the soft X-ray free electron laser under the condition of megahertz repetition frequency are solved, stable and linear light intensity attenuation is realized, and the attenuation magnitude is continuously adjustable.

The invention provides a sample detection method, system and equipment and a medium. The sample detection method comprises the following steps: acquiring a sample to-be-detected image of an X-ray free electron laser monopulse experiment; performing conversion processing on the to-be-detected image of the sample to obtain a binary image of the sample; performing contour recognition processing according to the sample binary image to obtain at least one sample contour data; and carrying out screening processing on the sample contour data based on a preset rule so as to obtain sample contour data meeting conditions and generate a visual image. According to the sample detection method, detection treatment of batch samples can be achieved, compliant samples are automatically obtained, and the screening efficiency and accuracy are improved.

The application discloses a kind of ultra-high vacuum four-knife slits suitable for soft X-ray free electron laser beam collimation, characterized in that, including ultra-high vacuum cavity and the four-knife slit completely located in ultra-high vacuum cavity, after soft X-ray free electron laser pulse enters ultra-high vacuum cavity from the front CF100 flange of ultra-high vacuum cavity, from the rear CF100 flange of ultra-high vacuum cavity, wherein: four-knife slit includes vertical direction double-knife slit and horizontal direction double-knife slit, respectively, to form constraint from horizontal and vertical direction to X-ray free electron laser beam.The application has the characteristics of high precision, high reliability, compact, simple structure, can work in ultra-high vacuum environment, etc.

The invention discloses a light source device, a light source system and a water window wave band full-coherence free electron laser generation method. The device comprises a harmonic generation unit used for accessing an electron beam and seed laser and generating low-order harmonics; and the at least two stages of cascaded amplifier units are connected with the harmonic generation unit, and are used for accessing low-order harmonic radiation, generating coherent harmonic radiation and tuning the coherent harmonic laser into high-order harmonic radiation so as to obtain the water window wave band full-coherent free electron laser pulse. According to the invention, the multi-stage amplifier units are constructed at the rear stage of the harmonic generation unit, and each subsequent amplifier unit is configured to resonate on a higher harmonic output and radiated by the previous amplifier unit, so that the harmonic radiation of the previous stage is used as an effective seed of the next stage, and the step-by-step up-conversion of the frequency is realized; and converting the frequency of the coherent radiation to a target higher harmonic step by step to obtain the water window wave band full-coherent free electron laser.

The application discloses a free electron laser system based on a plane metal grating, which is composed of an electron gun, a metal grating and a collector.The system generates periodic electron bunch strings through the electron gun, and when the electron bunch strings pass over the metal grating in parallel, the resonant mode of the metal grating is excited.Because the electron bunch strings are periodic, when the frequency of the electron bunch strings is consistent with the frequency of the resonant mode, the energy of the resonant mode is outputted in the form of Smith-Purcell super radiation, and the intensity of the coherent radiation will be much greater than the intensity of the ordinary spontaneous radiation generated by the continuous electron beam.In addition, when the resonant mode is near the continuous domain bound state, the Smith-Purcell super radiation will be further enhanced.The application utilizes the periodic electron bunch strings to excite the metal grating to generate coherent spontaneous radiation, and has the characteristics of low cost and strong practicability.