JP3241779B2 - Method and apparatus for generating high-brightness synchrotron radiation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The disclosed technology belongs to the field of technology for generating photons such as undulator light used in research divisions such as medicine, physics, and chemistry, and in practical facilities.

[0002]

2. Description of the Related Art As is well known, the rise of industry largely depends on rapidly developing science and technology, and in particular, the development of industrial technology based on physics such as electronics and quantum mechanics. There are remarkable applications and uses of light and laser in advanced industries that extend to micro-worlds as well as huge industries.

[0003] Recently, computer technology has been applied to various industries, and in lithography used for producing integrated circuits such as IC parts, if the wavelength of light is short in order to form a fine circuit pattern, The shorter the distance, the more accurate patterns can be drawn, so that ultraviolet rays are used instead of those that used to use visible light, and recently, X-ray lithography using X-rays with a submicron wavelength beyond the electron beam. And other technologies are also being used.

On the other hand, laser scalpels and the like are used for treatments such as metal surface processing and medical surgical operations, and laser utilization techniques for holography and the like are actively researched, developed and used, and have high accuracy and high energy. There is a demand for an excellent laser technology that can be used for a long time.

Among such optical techniques, as described above, the technique of using short-wavelength light such as X-ray lithography from the use of visible light has been used for nuclear power and elementary particle experimental physics. In electron beam accelerators such as trons, free electrons that are injected and fly around the storage ring receive acceleration at the deflecting unit to generate light, and use the light extracted at the deflecting unit, etc. Secondary optics, which should have nothing to do with the acceleration function for free electrons,
The light generated by the deflecting unit has a continuous wavelength, and
A spectroscope is required to select monochromatic light of the required wavelength from white light, and the system design is limited due to the arrangement of bending magnets in the deflection part of the storage ring, etc. And the maintenance and inspection become extremely complicated, resulting in high cost. In addition, since a predetermined monochromatic light is selected and extracted from the light generated in all directions in the deflecting unit, the spatial direction is extremely large. There is a disadvantage in that there is a problem that there is a loss in terms of energy, and there is a loss in the energy input.

[0006] In a system using such a spectroscope, not only the complicated installation of the spectroscope but also its management, control, and control.
It requires long-term experience and a high degree of skill to make adjustments and requires special skills.Therefore, there is a drawback that lacks versatility.In addition, sharp monochromatic light can be obtained due to the characteristics of the spectrometer during operation. There was a difficulty that it was difficult.

However, as an actual industrial requirement, for example, in a technical field such as a sample analysis in a metal industry or the like, an operation such as continuous scanning of light having different wavelengths is required. The potential for synchrotron radiation is latent.

In particular, recently, in the latest medical technology and IC technology, technologies using ultraviolet light having a short wavelength of, for example, 300 nm to 100 nm have been highlighted, and from visible light to ultraviolet light having the short wavelength. There has been a strong demand for the emergence of a system that enables selective extraction of scalp.

In some small electron storage rings, a so-called undulator or wiggler is provided in a linear portion to give fluctuation to free electrons in flight and emit light, but the output is weaker by orders of magnitude than FEL. In addition, it has both generation of synchrotron radiation and generation of laser light,
There is no device that can be used selectively.

On the other hand, Japanese Patent Application Laid-Open No.
As disclosed in Japanese Patent Application Laid-Open Publication No. H10-209, there is a configuration in which a plurality of synchrotrons are configured to circulate around a storage ring. However, in the above-described technology, the plurality of synchrotrons are arranged in a matrix. Since the deflection angles of the charged particle beam trajectories are all the same, the damping time is lengthened, and there is a bottleneck in that monochromatic light with high luminance can be obtained.

Further, since the beam trajectory is branched, a mechanism for suppressing the divergence of light is required.

Further, as described above, since the matrix structure is employed, there is a problem that the production and the management and control are complicated.

If the size of the conventional storage ring is reduced in size, the energy level of electrons that can be stored is reduced, but a sufficient amount of photons of uniform energy cannot be obtained. Had.

On the other hand, chemical lasers that have been widely used so far emit only a single color or only a few types of monochromatic systems. Therefore, separate devices are required depending on the application, and deterioration of the devices over time may occur. In addition, the oscillation wavelength is limited in steps, and there is a disadvantage that it does not always meet the demands of the industry.

In addition, various dedicated photon generators must be provided, and there is a disadvantage that they cannot be shared with the synchrotron radiation used for the X-ray lithography and the like.

To cope with this, for example, Japanese Patent Application No. 3-84391 (Japanese Unexamined Patent Application Publication No. Hei 7-222) of the prior application of one of the applicants.
As disclosed in the invention of No. 00, a free electron laser light (FEL) generator of a considerably large size has been developed.

The free electron laser beam (FE)
L) The generator 1 is briefly described with reference to FIG. 9. The free electrons 2 injected from a predetermined accelerator are flown along an equilibrium orbit by a septum magnet 3, a kicker magnet and the like, and the RF cavity 4 and a predetermined bending An undulator light is generated by a process of being turned by magnets 5, 5 and being bent by an undulator or wiggler inserted light source 6 by an alternating magnetic field, etc.
Undulator light 8 of a predetermined wavelength that is resonated at
As being taken out.

As for the operation of the RF system, as shown in FIG. 10, the RF transmitter 9 operates the RF amplifier 10 to operate the RF cavity 4.

[0019]

As described above, when radiated light such as the undulator light 8 is used for various advanced industries and practical technology development research, high-brightness radiated light, that is, the undulator light 8 is used. There is a strong demand for the emission of monochromatic light having high brightness as described above, and the potential demand for not only emission light having a constant brightness but also pulse waves and emission light having repetition is increasing depending on the application.

Therefore, in the conventional type undulator light generating device 1 as shown in FIGS.
The free electrons 2 orbiting the insertion light source 6 such as the F cavity 4 and the undulator or wiggler have a property of being scattered in the orbiting process, and conversely, a control technique for suppressing the property has been developed. .

If the diffusing force accumulates in the process in which the free electrons 2 circulate, a phenomenon in which the free electrons 2 protrude from the orbit (so-called instability) occurs. To suppress this phenomenon, a shorter so-called damping time is required. good.

The damping time is equal to the free electrons 2
It is known that the damping time becomes shorter as the circumference becomes shorter in a ring storing electrons of the same energy.

By the way, since the emittance of the beam of the storage ring is proportional to the square of the energy, it is difficult to design a storage ring having a high energy to obtain a low emittance.

In a single resonance system, the length of the suppression pulse of the undulator light 8 generated and the repetitive attitude are determined by the bunch and the number of bunches of the accumulated free electron beam.

In the comparatively large undulator light generating apparatus 1 as shown in FIGS. 9 and 10, the size of each mechanism is increased, and therefore, the design of the storage ring in the initial construction and assembling is ensured. There was a problem that it was difficult to obtain high accuracy.

When the damping time becomes longer,
After the light gains and amplifies due to the resonance between the light and the free electrons 2 in the insertion light source 6, the energy width of the free electrons 2 is widened. There is a potential problem that the effect is weakened, and as a result, emission of monochromatic light of high luminance cannot be obtained.

Although the wavelength region and the brightness of the radiated light such as the undulator light 8 vary depending on the storage ring, the shorter the wavelength and the higher the brightness of the light, the higher the energy inserted into the large storage ring. Although it is obtained from the light source 6, a system that can freely change the wavelength, pulse interval, and repetition rate has not been obtained so far, and its appearance is strongly expected in the industrial and research fields. It has been rare.

[0028]

SUMMARY OF THE INVENTION An object of the invention of this application is to provide an undulator generating apparatus such as an RF cavity and a bending magnet based on the above-mentioned prior art and an insertion light source, etc. The unit light source of the preceding unit system and the insertion light source of each unit system have a common free electron equilibrium orbit, and the undulator light from the upstream side is inserted into the insertion light source of each next unit system. An excellent method of generating high-brightness synchrotron radiation that benefits the energy technology application field in various advanced industrial research by enabling light and electrons to interact and obtain high-brightness monochromatic synchrotron with a short wavelength and high output. And to provide a device for direct use in the method.

[0029]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the configuration of the invention of this application, which has the above-mentioned object and aims at the above objects, has a short wavelength, high luminance and high energy. In obtaining monochromatic radiation, septum magnets, kicker magnets for free electrons inserted in the peripheral orbit, bending magnets in RF cavities, and undulators equipped with undulators with resonance systems and wiggler insertion light sources Make the device as compact as possible and form it in a series of vertically arranged multiple unit systems, and set the insertion light source of each unit system along the same linear axis, etc. The light from the insertion light source of the system, that is, the undulator light generated by the insertion light source of the unit system on the most upstream side The undulator light resonates with the free electrons in each insertion light source and is inserted into the light source sequentially in series in series and resonates, and the undulator light amplifies the energy. Return to narrow the spread of energy, shorten the damping time, obtain monochromatic radiation of high-brightness undulator light, and resonate so that the spread of energy does not change for each unit system. By doing so, monochromatic radiation of the undulator light can be obtained, and various high brightness can be generated by adjusting the phase of the RF cavity of the storage ring of each unit system according to a predetermined rule. In addition, since the above-mentioned unit systems can be assembled as standard in mass production, installation and adjustment can be performed accurately and cost can be reduced. The one in which has taken the technical means.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

9 and 10 will be described using the same reference numerals.

In the embodiment shown in FIG. 1, reference numeral 1 'denotes a high-brightness synchrotron radiation generator which forms the center of one aspect of the invention of the present application, and the high-brightness synchrotron radiation generator 1' is as shown in FIG. .. Shown in FIG. 2 are vertically arranged in multiple stages in series with the number of set stages as a unit system of the same structure mechanism (of course, this embodiment is merely one embodiment). 2), as shown in FIG. 2, RF cavities 3 having septum magnets 3 and kicker magnets into which free electrons 2 accelerated by a predetermined accelerator are injected and run on an equilibrium orbit are respectively provided at four corners in a direction perpendicular to each other. The storage ring 9 has bending magnets 5, 5,....

An insertion light source 6 of an undulator or a wiggler is interposed between a predetermined pair of bending magnets 5 and 5, and transmits the undulator light 8 to the insertion light source 6 of the next unit system 11 adjacent to the undulator light. The undulator light 8 from the previous stage is coaxially inserted directly into the insertion light source 6 in the next stage.

As shown in FIG. 4, the high-brightness synchrotron radiation generator 1 'is provided with a master RF oscillator 12, which is connected to the phase adjusters 13, 13,... Of each unit system 11, respectively. Connected to RF amplifier 14 and RF
It is connected to the cavity 4 so that the phase of each storage ring 9 can be adjusted.
As shown in FIG. 5, when the time t is plotted on the horizontal axis and the luminance L of light is plotted on the vertical axis, the phase of the RF cavity 4 is changed to
Undulator light 8 having high brightness in a spike shape shown in FIG.
In order to obtain an output as the undulator light 8 having a low luminance as shown in FIG. 6, and to obtain an output of the pulse-shaped undulator light 8 as shown in FIG. As shown in FIG. 8, a repetitive output wave determined by the bunch length of the pulse-like output can be obtained.

Note that T in FIGS. 5 to 8 indicates a cycle time of one pitch.

In the above configuration, the predetermined unit system 11
The free electrons 2 are injected into the storage ring 9 of FIG. 1, and the free electrons 2 injected by the septum magnet 3 are put on an equilibrium orbit to orbit the storage ring 9, and the phase of each RF cavity 4 is set to the master RF oscillator 12 (see FIG. 4). ), The undulator light 8 from the insertion light source 6 at the forefront (most upstream) is matched by the RF amplifier 14 via each phase adjuster 13, whereby mutual interference effect and resonance between light and free electrons 2 are caused. The light obtains energy by the action to perform amplification, and the widening of the energy width of the free electrons 2 is reduced by reducing the damping time to reduce the width of the energy. Undulator light 8 is generated.

In the process, as shown in FIG. 3, the undulator light 16 determined by the bunch length of the free electron group 15 resonates with the free electrons whose energy spread does not change in the storage ring of each unit 11, thereby increasing the brightness. Of the light pulse 17 can appear.

The embodiment of the invention of this application is not limited to the above-described embodiment. For example, the insertion light source 6 of each unit system 11 vertically connected in series as in the above-described embodiment is coaxial. And the undulator light 8 from the leading edge (most upstream) is not passed through the insertion light source 6 of each unit system 11 so that mutual interference and free electron resonance occur. Various modes can be adopted, such as providing a reflecting mirror or the like between them and inserting the undulator light 8 from the unit system 11 at the preceding stage into the insertion light source 6 of each unit system 11.

The configuration of the RF phase in each unit system uses the RF and electron phases of the already-developed linac klystron, which are within the scope of design change.

[0040]

As described above, according to the invention of this application, high-intensity radiation such as undulator light having a short wavelength and high energy, which is extremely deeply demanded in the electronics industry, the medical industry, and even these research institutions, etc. In generating the light, a system such as a free electron laser light (FEL) generator using the maximum undulator light is vertically arranged in a predetermined number of stages, and the undulator light from the upstream unit system, that is, from the upstream unit system, is provided. Directly penetrate an inserted light source such as an undulator of each unit system to cause mutual interference, and also resonate with the circulating free electrons to shorten the length of the linear portion including the RF cavity of the storage ring in each unit system. After reducing the damping time and amplifying the light output due to the resonance between the undulator light and the free electrons, this is returned to narrow the energy spread. Excellent effect that it is possible to obtain the radiation undulator light such a high brightness are obtained.

The bunch length of the accumulated free electron beam by adjusting the phase of the resonance system of each ring;
Also, the pulse length and the repetition time can be prevented from being restricted by the number of bunches, and the pulse width determined by the bunch length can be varied to obtain high-energy high-intensity radiation. It is possible to obtain higher-intensity radiation light than conventional free electron laser light (FEL), and it is also possible to produce high-intensity radiation light having various repetition modes from a constant luminance. The effect is achieved.

Further, there is also an effect that high-intensity radiated light of the same wavelength can be obtained with energy due to the series vertical arrangement of the undulator light generating device having a large storage ring and the small storage ring.

[Brief description of the drawings]

FIG. 1 is an overall schematic plan view of an apparatus of the present invention.

FIG. 2 is a schematic plan view of a unit of the apparatus.

FIG. 3 is a graph showing a correspondence relationship between a bunch of free electrons, high-brightness radiation, and a pulse.

FIG. 4 is a schematic diagram of an RF phase adjustment system.

FIG. 5 is a graph of a spike-like pulse of high-intensity radiation.

FIG. 6 is a graph of high-brightness emitted light having the same high brightness.

FIG. 7 is a graph of pulsed high-intensity radiation.

FIG. 8 is a unit diagram showing repeated generation of pulses.

FIG. 9 is a system schematic diagram of an undulator light generation device based on the prior art.

FIG. 10 is a schematic diagram of the same RF oscillation system.

[Explanation of symbols]

 Reference Signs List 2 free electron 4 RF cavity 6 insertion light source 9 storage ring 7,7 resonance system 1 high-brightness synchrotron radiation generator

Claims (2)

(57) [Claims] 1. A high-brightness synchrotron radiation generating method in which injected free electrons circulate around a storage ring through an insertion light source through an RF cavity to extract monochromatic undulator light with low emittance. The process of the ring orbit is performed in a plurality of unit systems vertically arranged in series, and the undulator light from the preceding unit system is directly inserted into the insertion light source of each stage unit system, so that the interaction between light and electrons is performed. A high-brightness synchrotron radiation generating method characterized by obtaining high-brightness monochromatic synchrotron radiation having a short wavelength and a large output. 2. A high-brightness synchrotron radiation generating apparatus using a storage ring provided with a septum magnet, an RF cavity, a bending magnet, and an insertion light source for free electrons to be injected, and a resonance system is provided in the insertion light source. And a unit system having a function from the septum magnet to the resonance system is vertically arranged in a plurality of stages in series.