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Diffraction-limited imaging on the 200-inch telescope.

机译：200英寸望远镜上的衍射极限成像。

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摘要

We have used the technique of non-redundant masking at the Palomar 200-inch telescope and radio VLBI imaging software to make optical aperture synthesis maps of two binary stars, {dollar}beta{dollar} Corona Borealis and {dollar}sigma{dollar} Herculis. The dynamic range of the map of {dollar}beta{dollar} CrB, a binary star with a separation of 230 milliarcseconds is 50:1. For {dollar}sigma{dollar} Her, we find a separation of 70 milliarcseconds and the dynamic range of our image is 30:1. These demonstrate the potential of the non-redundant masking technique for diffraction-limited imaging of astronomical objects with high dynamic range.; We find that the optimal intergration time for measuring the closure phase is longer than that for measuring the fringe amplitude. There is not a close relationship between amplitude errors and phase errors, as is found in radio interferometry. Amplitude self calibration is less effective at optical wavelengths than at radio wavelengths. Primary beam sensitivity correction made in radio aperture is not necessary in optical aperture synthesis.; Effects of atmospheric disturbances on optical aperture synthesis have studied by Monte Carlo simulations based on the Kolmogorov theory of refractive-index fluctuations. For the non-redundant masking technique with {dollar}rsb{lcub}c{rcub}{dollar}-sized apertures, the simulated fringe amplitude gives an upper bound of the observed fringe amplitude. A smooth transition is seen from the non-redundant masking regime to the speckle regime with increasing aperture size. The limiting magnitude of optical aperture synthesis with {dollar}rsb{lcub}c{rcub}{dollar}-sized apertures and that with apertures larger than {dollar}rsb{lcub}c{rcub}{dollar} are derived.; Monte Carlo simulations are also made to study the sensitivity and resolution of the bispectral analysis of speckle interferometry. We present the bispectral modulation transfer function and its signal-to-noise ratio at high light levels. The signal-to-noise ratio of the bispectrum at arbitrary light levels is derived in the mid-spatial-frequency range.; The non-redundant masking technique is suitable for imaging bright objects with high resolution and high dynamic range, while the faintest limit will be better pursued by speckle imaging.
机译：我们已经在Palomar 200英寸望远镜和射电VLBI成像软件上使用了非冗余掩膜技术，制作了两个双星，即{beta} {dollar} Corona Borealis和{dollar} sigma {dollar}的光圈合成图大力神。 {dollar} beta {dollar} CrB（间隔为230毫秒）的双星的动态范围为50：1。对于{dollar} sigma {dollar}她，我们发现相隔70毫秒，图像的动态范围为30：1。这些证明了非冗余掩膜技术在具有高动态范围的天文物体的衍射极限成像中的潜力。我们发现，用于测量闭合相位的最佳积分时间比用于测量条纹幅度的最佳积分时间长。如在无线电干涉仪中发现的，幅度误差和相位误差之间没有紧密的关系。振幅自校准在光学波长下的效果比在无线电波长下的效果差。在光圈合成中，不需要在光圈中进行一次光束灵敏度校正。大气干扰对光学孔径合成的影响已通过基于Kolmogorov折射率波动理论的Monte Carlo模拟进行了研究。对于具有{dolb} rsb {lcub} c {rcub} {dollar}大小的孔径的非冗余遮罩技术，模拟条纹幅度给出了观察到的条纹幅度的上限。随着孔径的增加，可以看到从非冗余掩蔽方案到斑点方案的平滑过渡。推导了具有{dolb} rsb {lcub} c {rcub} {dollar}大小的孔径和大于{dollar} rsb {lcub} c {rcub} {dollar}的孔径的光学孔径合成的极限大小。还进行了蒙特卡洛模拟，以研究斑点干涉法双光谱分析的灵敏度和分辨率。我们提出了双光谱调制传递函数及其在高光照水平下的信噪比。双光谱在任意光水平下的信噪比是在中空间频率范围内得出的。非冗余掩膜技术适用于对具有高分辨率和高动态范围的明亮物体进行成像，而散斑成像将更好地追求最暗的极限。

著录项

  • 作者

    Nakajima, Tadashi.;

  • 作者单位

    California Institute of Technology.;

  • 授予单位 California Institute of Technology.;
  • 学科 Physics Astronomy and Astrophysics.
  • 学位 Ph.D.
  • 年度 1989
  • 页码 162 p.
  • 总页数 162
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 天文学;
  • 关键词

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