共查询到20条相似文献,搜索用时 46 毫秒
1.
LIU Zhen YANG Lin CHEN Bo CHEN Bin & CAO JianLin State Key Laboratory of Applied Optics Changchun Institute of Optics Fine Mechanics Physics Chinese Academy of Sciences Changchun China Graduate University of Chinese Academy of Sciences Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(3)
This paper first reviews an EUV normal incidence solar telescope that we have developed in our lab. The telescope is composed of four EUV telescopes and the operation wavelengths are 13.0 nm, 17.1 nm, 19.5 nm, and 30.4 nm. These four wavelengths, fundamental to the research of the solar activity and the atmosphere dynamics, are always chosen by the EUV normal incidence solar telescope. In the EUV region, almost all materials have strong absorption, so optics used in this region must be coated by the multila... 相似文献
2.
Bo Chen Zhen Liu Lin Yang Liang Gao Fei He XiaoGuang Wang QiLiang Ni 《中国科学G辑(英文版)》2009,52(11):1806-1809
In this paper we have reviewed our achievements in soft X-ray and extreme ultraviolet (EUV) optics. Up to now, the research
system of soft X-ray and EUV optics has been established, including light sources, detectors, calibrations, optical testing
and machining of super smooth mirrors, and fabrications of multilayer film mirrors. Based on our achievements, we have developed
two types of solar space telescopes for the soft X-ray and EUV space solar observations. One is an EUV multilayer normal incident
telescope array including 4 different operation wavelength telescopes. The operation wavelengths of the EUV telescope are
13.0, 17.1, 19.5 and 30.4 nm. The other is a complex space solar telescope, which is composed of an EUV multilayer normal
incident telescope and a soft X-ray grazing incident telescope. The EUV multilayer normal incident telescope stands in the
central part of the soft X-ray grazing incident telescope. The normal incident telescope and the grazing incident telescope
have a common detector. The different operation wavelengths can be changed by rotating a filter wheel. 相似文献
3.
4.
Propagation and Damping of Two-Fluid Magnetohydrodynamic Waves in Stratified Solar Atmosphere
下载免费PDF全文
![点击此处可从《中国物理快报》网站下载免费的PDF全文](/ch/ext_images/free.gif)
An extreme ultra-violet(EUV) wave is characterized as a bright pulse that has emanated from the solar eruption source and can propagate globally in the solar corona. According to one leading theory, the EUV wave is a fast magnetoacoustic wave, as the coronal counterpart of the Moreton wave in the chromosphere. However, previous observations have shown that the EUV wave differs significantly from the Moreton wave in both velocity and lifetime. To reconcile these differences, here we analyze the wave characteristics of a two-fluid MHD model in the stratified solar atmosphere with a height-dependent ionization rate. It is found that the collision between neutral and ionized fluids is able to attenuate the wave amplitude, while causing a slight change in its propagation velocity. Because the chromosphere has the lower ionization rate and the stronger magnetic fields than the corona,the velocity of the Moreton wave is much higher than that of the EUV wave. In contrast to the Moreton waves damped strongly by the collision between neutral and ionized fluids, the EUV wave in the fully ionized corona is able to propagate globally on a time scale of several hours. Our results support the previous theory that fast magnetoacoustic waves account for both EUV and Moreteon waves in the different layers of the solar atmosphere. 相似文献
5.
极紫外光谱观测和诊断是研究太阳大气基本物理过程的最重要手段之一。但因为波长短,很多可见光仪器的设计方案不再适用,且极紫外观测只能在太空中开展。国际上现有卫星上的太阳极紫外成像仪和光谱仪都有各自的不足,比如极紫外成像仪不能获得高光谱分辨率的谱线信息;狭缝式光谱仪通过扫描可得到活动区域的信息,但扫描时间过长,对于研究剧烈变化的太阳活动有很大的局限性。这些不足制约了对日冕物质抛射(CME)和耀斑等太阳活动的高精度观测及对其机理的研究:无法看到CME在内日冕的加速过程,而且无法将可见光看到的CME现象同极紫外看到的日面源区直接联系;缺少观测目标的视向速度信息,难以识别CME的触发过程。采用多级衍射成像方式的一种新型太阳极紫外成像仪,除实现传统极紫外成像仪功能外,还可以在太阳活动变化过程中同步获得全日面各区域的光谱信息。新型成像仪可以得到高光谱分辨率数据,用于反演低日冕的等离子体视向速度,获得全日面的速度分布,与同时得到的高空间分辨率图像相结合,可以识别太阳活动现象对应的物质运动, 为空间科学研究提供数据;因为没有狭缝和运动部件,可以实现对大视场的太阳活动区域的高时间分辨率成像,有利于捕捉日面活动的快速变化。新型成像仪采用无狭缝光谱分光成像的设计理念,即同一时间把一定光谱带宽的信息记录到一个二维的图像上,此过程可以看成是从某一个角度将空间和光谱数据立方体投影到一个面上,然后再利用反演得到空间分辨图像和光谱信息。多级光谱成像的光学设计与传统光谱仪最大的不同是其不存在逐行扫描的狭缝,这使得其能够同时获得大视场内太阳的空间信息和光谱信息。因为极紫外波段的特殊性,以及本仪器面向卫星遥感应用,不可能像可见光波段或者医用CT机一样实现很多衍射级的同时成像。因此,新型极紫外成像仪光学系统由反射镜、色散光栅和五个探测器组成,入射的太阳极紫外辐射经过光栅色散后分别由五个级次的探测器接收,其中四个探测器分部接收±1和±2衍射级图像,另外一个接收0级图像。空间信息可以直接从0级图像得到,而光谱信息则需要根据五个级次成像的反演结果得出。介绍了光学系统的设计以及反演算法,并分析了反演算法的误差。光路基于变间距光栅设计,可实现空间分辨率1.8 arcsec·pixel-1, 光谱分辨率7.8×10-3 nm·pixel-1,同时减小了体积和重量,适合空间应用。 相似文献
6.
I. M. Chertok A. V. Belov V. V. Grechnev 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(6):796-798
By data of the 23rd solar cycle, it is shown that close statistical relations exist between quantitative parameters of dimmings and arcades caused by solar coronal mass ejections (CMEs), on the one hand, and magnitudes of non-recurrent Forbush-decreases of the galactic cosmic ray flux, as well as the propagation time of disturbances from the Sun to the Earth, on the other hand. Parameters of dimmings and arcades, in particular their summarized magnetic flux of the prolonged field at the photospheric level, were calculated by data of the EUV SOHO/EIT telescope in the 195 Å Received results mean that the scale, characteristics, and propagation time of interplanetary disturbances to the Earth are determined to a large degree by measurable parameters of solar eruptions and may be estimated in advance by observations of dimmings and arcades in the EUV range. 相似文献
7.
8.
9.
10.
太阳过渡区是太阳色球层顶到日冕底部的大气薄层。厚度仅几百千米,但其间太阳等离子体参数变化剧烈。过渡区的辐射多为光学薄的远紫外、极紫外发射谱线和背景连续谱线。由于地球大气的吸收,过渡区紫外光谱需通过天基观测才能实现。近几十年来,星载仪器的成功发射为太阳过渡区的研究打开了新纪元。工作回顾了太阳过渡区紫外光谱的观测历史和各类星载仪器,特别介绍了近十几年几种重要的光谱仪器。详细阐述了过渡区紫外光谱的发生率、电子密度和电子温度的诊断原理。讨论了过渡区紫外谱线的形状,并以SOHO/SUMER光谱仪为例介绍了表征谱线的几种重要参量及其物理意义。 相似文献
11.
Zuppella P Monaco G Corso AJ Nicolosi P Windt DL Bello V Mattei G Pelizzo MG 《Optics letters》2011,36(7):1203-1205
We have developed an Ir/Si multilayer for extreme ultraviolet (EUV) applications. Normal incidence reflectance measurements of a prototype film tuned to 30 nm wavelength show superior performance relative to a conventional Mo/Si multilayer structure; we also find good stability over time. Transmission electron microscopy and electron dispersive x-ray spectroscopy have been used to examine the microstructure and interface properties of this system: we find amorphous Si layers and polycrystalline Ir layers, with asymmetric interlayer regions of mixed composition. Potential applications of Ir/Si multilayers include instrumentation for solar physics and laboratory EUV beam manipulation. 相似文献
12.
Christophe Hecquet Franck Delmotte Marie-Fran?oise Ravet-Krill Sébastien de Rossi Arnaud Jérome Fran?oise Bridou Fran?oise Varnière Evgueni Meltchakov Frédéric Auchère Angelo Giglia Nicola Mahne Stefano Nanaronne 《Applied Physics A: Materials Science & Processing》2009,95(2):401-408
In this paper, we present a study on two-channel multilayer mirrors which can operate at two wavelengths in Extreme Ultraviolet
(EUV) spectral range. We propose a new method to design two-channel EUV multilayer mirrors with enhanced spectral selectivity.
The mirror structure is a stack of two periodic multilayers separated by a buffer layer. We have defined the main parameters
which allow adjustment of the distance between different order Bragg’s peak and of wavelength positions of reflectivity minima.
Two mirrors have been designed and deposited for solar EUV telescope applications by using this method. The first mirror reflects
Fe IX–X line (17.1 nm) and Fe XVI (33.5 nm) lines with attenuation of the He II line (30.4 nm). The second mirror reflects
Fe IX–X and He II lines with attenuation of Fe XV (28.4 nm) and Fe XVI lines. Measurements with synchrotron radiation source
confirm that, in both cases, for these mirrors, we are able to adjust reflectivity maxima (Bragg peak position) and minima.
Such multilayers offer new possibilities for compact design of multi-wavelength EUV telescopes and/or for high spectral selectivity. 相似文献
13.
We have fabricated periodic multilayers that comprise either Si/Tb or SiC/Tb bilayers, designed to operate as narrowband reflective coatings near 60 nm wavelength in the extreme ultraviolet (EUV). We find peak reflectance values in excess of 20% near normal incidence. The spectral bandpass of the best Si/Tb multilayer was measured to be 6.5 nm full width at half-maximum (FWHM), while SiC/Tb multilayers have a more broad response, of order 9.4 nm FWHM. Transmission electron microscopy analysis of Si/Tb multilayers reveals polycrystalline Tb layers, amorphous Si layers, and relatively large asymmetric amorphous interlayers. Thermal annealing experiments indicate excellent stability to 100 degrees C (1 h) for Si/Tb. These new multilayer coatings have the potential for use in normal incidence instrumentation in a region of the EUV where efficient narrowband multilayers have not been available until now. In particular, reflective Si/Tb multilayers can be used for solar physics applications where the coatings can be tuned to important emission lines such as O V near 63.0 nm and Mg X near 61.0 nm. 相似文献
14.
In this article, we report that by using the intensity ratio of the (2-2) to (1-2) component of CI emission lines at about 165.7 nm, we determined the optical depth at the line center of the (2-2) component of CI emission lines by escape factor treatment. The optical depth at the line center of the (2-2) component is calculated to be 0.9998, which is a more reasonable value of solar spectral lines than the value that has been reported. The variation of the optical depth at the line center for different positions from the solar limb is discussed. Using the measured abundance of carbon and the results of ionization balance calculations, we estimate the electron density in the CI emitting region. The density of hydrogen is estimated in the CI emitting region by this method, and is testified to be a better value than the value that has been reported. This discussion will be significant in the analysis of opacity on the solar ultraviolet (UV) or extreme-ultraviolet (EUV) spectrum. 相似文献
15.
A laser-plasma EUV source is described, which is going to be utilized for characterization of EUV optical components and sensoric devices in the wavelength region from 11 to 13 nm. EUV radiation is generated by focusing a Nd:YAG laser into a double stream gas puff target. By the use of different target gases, broadband as well as narrow-band EUV radiation can be obtained. The emission characteristics of the radiation is monitored by the help of different diagnostic tools including a pinhole camera, an EUV spectrometer, and various EUV photodiodes, either directly or after reflection from multilayer mirrors. Theoretical calculations of collision-induced energy transfer are given in order to explain the observed high degree of electronic excitation in the utilized target gases. 相似文献
16.
P. W. Wachulak M. C. Marconi A. Isoyan L. Urbanski A. Bartnik H. Fiedorowicz R. A. Bartels 《Opto-Electronics Review》2012,20(1):1-14
Imaging systems with nanometer resolution are instrumental to the development of the fast evolving field of nanoscience and
nanotechnology. Decreasing the wavelength of illumination is a direct way to improve the spatial resolution in photon-based
imaging systems and motivated a strong interest in short wavelength imaging techniques in the extreme ultraviolet (EUV) region.
In this review paper, various EUV imaging techniques, such as 2D and 3D holography, EUV microscopy using Fresnel zone plates,
EUV reconstruction of computer generated hologram (CGH) and generalized Talbot self-imaging will be presented utilizing both
coherent and incoherent compact laboratory EUV sources. Some of the results lead to the imaging with spatial resolution reaching
50 nm in a very short exposure time. These techniques can be used in a variety of applications from actinic mask inspection
in the EUV lithography, biological imaging to mask-less lithographic processes in nanofabrication. 相似文献
17.
R. Rakowski A. Bartnik H. Fiedorowicz F. de Gaufridy de Dortan R. Jarocki J. Kostecki J. Miko?ajczyk L. Ry? M. Szczurek P. Wachulak 《Applied physics. B, Lasers and optics》2010,101(4):773-789
The paper describes a debris-free, efficient laser-produced plasma source emitting EUV radiation. The source is based on a double-stream Xe/He gas-puff. Its properties and spectroscopic signatures are characterized and discussed. The spatio-spectral features of the EUV emission are investigated. We show a large body of results related to the intensity and brightness of the EUV emission, its spatial, temporal, and angular behavior and the effect of the repetition rate as well. A conversion efficiency of laser energy into EUV in-band energy at 13.5 nm of 0.42% has been gained. The electron temperature and electron density of the source were estimated by means of a novel method using the FLY code. The experimental data and the Hullac code calculations are compared and discussed. The source is well suited for EUV metrology purposes. The potential of the source for application in EUV lithography was earlier demonstrated in the optical characterization of Mo/Si multi-layer mirrors and photo-etching of polymers. 相似文献
18.
S. D?ring F. Hertlein A. Bayer K. Mann 《Applied Physics A: Materials Science & Processing》2012,107(4):795-800
An EUV reflectometer for the analysis of surfaces and thin films regarding refractive index, surface roughness, and mass density at the wavelength of 12.98?nm was developed. The setup uses a laser produced plasma source with an oxygen gas puff target for the generation of narrow-band EUV radiation and a flexible Kirkpatrick–Baez optics for focusing. We present EUV reflectometry (EUVR) measurements conducted on a series of carbon thin films to determine thickness and mass density of the coatings. In case of the thickness measurements results are compared to data obtained from nondestructive standard methods, i.e., grazing incidence X-ray reflectometry and spectroscopic ellipsometry. In addition, we propose a method to deduce the mass density of a sample directly from the fitted index of refraction obtained from EUVR measurements. 相似文献
19.
采用波长13.5 nm的极紫外光作为曝光光源的极紫外光刻技术是最有潜力的下一代光刻技术之一, 它是半导体制造实现10 nm及以下节点的关键技术. 获得极紫外辐射的方法中, 激光等离子体光源凭借转换效率高、收集角度大、碎屑产量低等优点而被认为是最有前途的极紫外光源. 本文开展了脉冲TEA-CO2激光和Nd:YAG激光辐照液滴锡靶产生极紫外辐射的实验, 对极紫外辐射的谱线结构以及辐射的时空分布特性进行了研究.实验发现: 与TEA-CO2激光相比, 较高功率密度的Nd:YAG激光激发的极紫外辐射谱存在明显的蓝移; 并且激光等离子体光源可以认为是点状光源, 其极紫外辐射强度随空间角度变化近似满足Lambertian分布. 相似文献
20.
极紫外多层膜技术研究进展 总被引:2,自引:0,他引:2
在极紫外波段,任何材料都表现出极强的吸收特性,因此,采用多层膜实现高反射率是构建正入射式光学系统的唯一途径。本文总结了极紫外多层膜的发展进程,叙述了制备极紫外多层膜的关键技术(磁控溅射、电子束蒸发、离子束溅射)以及它们涉及的相关设备。由于多层膜反射式光学元件主要应用于极紫外光刻与极紫外天文观测,文中重点讨论了极紫外光刻系统对多层膜性能的要求,镀膜过程中的面形精度和热稳定性等问题;同时介绍了极紫外天文观测中使用的多层膜的特点,特别讨论了多层膜光栅的制备技术和亟待解决的问题。 相似文献