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Volume 18, Issue 11
Displaying 1-18 of 18 articles from this issue
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Hiroaki ARITOME1990 Volume 18 Issue 11 Pages 855
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSDownload PDF (141K) -
Takayasu MOCHIZUKI1990 Volume 18 Issue 11 Pages 856-860
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSTarget atomic number dependence and laser wavelength dependence of the x-ray radiation spectrum from laser-produced plasmas are reviewed and a high power moving slab glass laser is described as a possible candidate driver to put the x-ray source into a practical use.View full abstractDownload PDF (498K) -
Hiroyuki DAIDO, Yoshiaki KATO1990 Volume 18 Issue 11 Pages 861-870
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSHigh brightness laser-plasma x-ray sources are reviewed. Recent progress in development of soft x-ray lasers including electron collisonal pumping and recombination pumping schemes is reported. The high brightness laser plasma incoherent x-ray sources for x-ray microscopy application are also described.View full abstractDownload PDF (1146K) -
Tamio HARA, Yoshinobu AOYAGI1990 Volume 18 Issue 11 Pages 871-878
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSAmplified spontaneous emission of Al ions was observed in a recombining plasma produced by a low-power driving laser of only 2 joules. This lasing was achieved by sharply focusing a pumping glass laser (5 ns FWHM) to a line 40 μm wide and 12 mm long onto a slab target. The spectral lines (time integrated) in the soft-X-rayregion were observed by a flat-field-type grazing incidence spectrograph which axially viewed the plasma with a spatial resolution of 200 μm. The measured gain coefficients are 3.4, 4.5, 3.4, and 3.5 cm-1 for the 105.7 Å (3d-51) and 154.7 Å (3d-4f) in Al XI and for the 123.Å (3d-5f) and 177.8 Å (3d-4f) in Al X, respectively. The gain was observed in a large area of 500μm×600 μm around z=0.8 mm. As Al XI line emissions continue during about 6 ns (FWHM), a soft-X-ray laser resonator is expected to be effective. Electron temperature in the plasma inthe neighborhood of the target was estimated by a filter absorption method to be 400±100 eV, which is hot enough to produce Al11+ ions with high density. It is considered that plasma is sequentially heated up to high temperature by a train of laser pulses of short time intervals.View full abstractDownload PDF (733K) -
Ikuo OKADA, Seiich ITABASHI, Yasunao SAITO, Hideo YOSHIHARA1990 Volume 18 Issue 11 Pages 879-884
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSEmploying a gas-puff-z-pinch plasma, a high brightness plasma x-ray source has been developed. The stable x-ray output is attained by using a fast-acting gas valve, capable of operating stably under gas plenum pressure below 300 Torr.. With this x-ray source, 1-1.4nm x-rays with 100J per pulse (300W average power) areobtained using Ne gas plasma in a 3pps repetition-rate discharge. In the axial direction of the columnar plasma, the x-ray spectral features vary from the primary profile due to x-ray absorption by high-density plasma. Damage to the x-ray extraction window is drastically reduced by forming a mass of gas swarm in front of the window to take away the remained particles, which could not be removed by the magnetic filed and plasma reflecting plate.View full abstractDownload PDF (927K) -
Hironari YAMADA1990 Volume 18 Issue 11 Pages 885-891
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSFive compact supeconducting light sources for synchrotron radiation (SR) are under development in the world. Some of them have already been utilized for lithography. Superconducting SR-source are not only small, but also have profitable features, high briliance and easier operation compared to a normal conducting SR source for a UV, VUV, and soft X-ray. This paper reports the present status of the superconducting SR soureces. Particularly, some detailes of AURORA which is made of a single superconducting magnet are presentd. Also mentioned is that the compact SR-source is useful to generate coherent millimeter or submillimeter waves.View full abstractDownload PDF (1461K) -
Hisao FUJISAKI1990 Volume 18 Issue 11 Pages 892-897
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe X-ray focusing efficiency of the Fresnel zone plate (FZP) used for X-ray microscopes is only 10%; this low efficiency necessiates a strong X-ray source and/or a long exposure time. This problem is at last partially overcome by usingthe phase zone plate (PZP). The PZP replaces the opaque zones of the FZP with transparentones which shift the phase of X-rays by π radians. The focusing efficiency of the ideal PZP is 40%. For such a PZP it is essential to find materials which have high transparency at a given thickness to induce a π-radian phase shift. The search of such materials and the investigation of the X-ray focusing properties of the PZP are performed by computer simulation and experiments using a nickel PZP, leading us to an idea of a new type of zone plate, a gradient refractive index phase zone plate (GRIPZP), whose focusing efficiency is higher than that of PZP's.View full abstractDownload PDF (865K) -
Koujun YAMASHITA1990 Volume 18 Issue 11 Pages 898-903
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSMultilayer reflectors play an important role in developing X-ray optical systems, such as X-ray telescope and microscpe in the wavelength region of 1-300A, where the normal incidence optics are no more applicable by making use of the total external reflection. The high reflectivity of multilayer reflectors in the limited wavelength band makes it possible to construct the normal incidence optical systems in the wavelength region of 30-300A. Moreover, their application to the reflecting surface of a grazing incidence mirror makes the reflectivity in the shorter wavelength region enhanced without squeezing the total reflection. We present here our recent progress in the fabrication of multilayer reflectors and their application to X-ray telescope and microscope.View full abstractDownload PDF (887K) -
Yoshikazu ISHII, Hisataka TAKENAKA1990 Volume 18 Issue 11 Pages 904-909
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSMultilayers can be used as dispersion elements ndfocusing mirrors for soft x-ray. We develop new reflective optical elements utilizing themultilayer . Flat and curved large area multilayers are fabricated using our newly developed magnetron sputtering method. The multilayers are uniform in layer period within about ±1%. The reflectivity of the multilayers agrees well with theoretical calculations. The focusing properties of the curved multilayers are in agreement with ray-tracing calculations. An excellent reflectivity of 46% at l3nm wavelength is obtained. This reflectivity is sufficient for use as the focusing mirror for soft x-ray.View full abstractDownload PDF (935K) -
Harumasa ITO, Etsuo BAN1990 Volume 18 Issue 11 Pages 910-915
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSWe developed a noncontact forming method to farbricate a grazing incidence X-ray mirror with a short focal length. The inner surface of a glass tube is very smooth, well reflecting even for a hard X-rays. To make use of this surface, we developed a technique with a combination of a pressurized gas from inside, an axial tension, and a thermal process applied to the tube by a heater programmed by a computer. A mirror of a focal length less than 300mm with a good reflectivity for X-rays is produced by “the thermal control method”. The mirrors show the properties as designed. A system of an X-ray microscope is constructed using the mirror as a condenser mirror and that as an object mirror. A system of a scanning system without the mirror is comparatively examined.View full abstractDownload PDF (772K) -
Shinya OHBA1990 Volume 18 Issue 11 Pages 916-922
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSScince 1981, the characteristics of solid state imaging devices such as charge coupled devices (CCD) have been improved and their sales have been increasing, due mainly to the popularization of home-use video cameras. Chip size has been down-sized from 2/3 inch lenz format to 1/3 inch. Sensitivity has been growing 100 times in the post 10 years. High definition format CCDs with 2 mega pixels were also proposed, leading to a small cell size of around 7μm×7μm. In this paper, the virtual phase CCD, which was developed for X-ray sensing, is also described.View full abstractDownload PDF (683K) -
Hiroshi TSUNEMI1990 Volume 18 Issue 11 Pages 923-930
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSX-ray detection below 10 keV has made great progress with a Charge Coupled Device (CCD). The greatest advantage to use CCD is that it has a good energy resolution as well as a high spatial resolution. Several efforts are done on the development of the X-ray CCD in Europe and in U. S. A. We present the results obtained with the CCD developed in MIT/Lincoln which is scheduled to be boarded on the next Japnese astronomy satellite Astro-D. Astro-D will be the first space observatory using the X-ray CCD. We also show the results obtained with CCD available in Japan. The requirements for the future X-ray CCD are discussed.View full abstractDownload PDF (1025K) -
Katsumi MIZUNOE1990 Volume 18 Issue 11 Pages 931-937
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSX-ray microscopes for observing biological specimens are discribed. Schematics of the x-ray microscopes are given for several types of imaging techniques, contact imaging, a projection x-ray, scanning x-ray, and imaging x-ray microscopes. X-ray optical arrangements of the imaging x-ray microscope using a laser-plasma x-ray source and zone plates are shown for estimating incident photon numbers on one pixel of CCD.View full abstractDownload PDF (631K) -
Masataka KADO, Kazuo A. TANAKA, Ryosuke KODAMA, Tatsuhiko YAMANAKA, Ko ...1990 Volume 18 Issue 11 Pages 938-943
Published: November 29, 1990
Released on J-STAGE: July 30, 2010
JOURNAL FREE ACCESSA Schwarzschild type x-ray microscope has been designed, constructed, and tested. We calculated ray traces for a working distance of 1500 mm and a magnification of 15, taking account of the x-ray scattering due to mirror surface roughness. The calculation shows that this x-ray microscope can achieve a spatial resolution less than 0.3 μm. Ni/Cmultilayers were used as x-ray mirrors, which have the thickness (2d) of 7 nm and 30 layer pairs. These mirrors were coated by an electron beam evaporation method, with the substrate being cooled with liquid nitrogen. The reflectivity was measured with Al-Ka line x-ray and found to be 6%. The microscope demonstrated a spatial resolution of less than 0.5 μm at the 15 magnification and x-ray wavelength of 7nm. When bright laser-produced plasmas were used as an x-ray source, images can be recorded in a 400 ps laser pulse.View full abstractDownload PDF (971K) -
Kunio SHINOHARA1990 Volume 18 Issue 11 Pages 944-950
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe progress in the application of X-ray microscopy to biology is reviewed with respect to the observation of human chromosomes. Isolated chromosomes, unstained and dried without fixative, were observed by X-ray contact microscopy at high resolution. The 'beadson- a-string' structure was observed in stretched portions of chromosome fibers. Detailed analysis of the results shows that the diameters of the thin filaments and small particles were 12.2± 2.1 nm and 31.4±13.2 nm, respectively. These sizes correspond to those of fibers composed of nucleosomes and particle units called superbeads revealed by electron microscopy. Progress in efforts toward the observation of hydrated specimens and three-dimensional observation is also reviewed. The problem of radiation damage tospecimens caused by imaging X-rays may become serious for the application of X-ray microscopy to hydrated intact biological organisms, but may be circumvented by making a proper choice of X-ray source and optics.View full abstractDownload PDF (1488K) -
Katsuhisa USAMI, Tatsumi HIRANO1990 Volume 18 Issue 11 Pages 951-958
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSHigh resolution, tunable monochromatic X-ray CT based on SR has been constructed and its functions are investigated. Some monolithic (channel cut) type monochromators are used to monochromate SR. An X-ray photo-diode array detector is used as a one dimensional detector and a high resolution X-ray pickup tube as a two dimensional detector. It is demonstrated that the distribution and concentration of a specific element in a sample can be obtained by means of an energy subtruction method, and a spatial resolution of 10 μm is achieved with the X-ray pickup tube.View full abstractDownload PDF (1688K) -
Kouichi MURAKAMI1990 Volume 18 Issue 11 Pages 959-963
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThis paper briefly reviews the laser-plasma pulse X-ray spectroscopy performed during laser annealing and laser ablation of silicon. A novel apparatus for the laser-plasma pulse X-ray spectroscopy introduced here enables us to measure a single event with one pulse of laser-plasma X-rays and is expected to be a very powerful technique for in-situ measurements during processing and the epitaxial growth of semiconductors and other materials.View full abstractDownload PDF (506K) -
1990 Volume 18 Issue 11 Pages plate1-plate2
Published: November 29, 1990
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSDownload PDF (5476K)
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