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引力波的直接观测已开启引力波天文学的新篇章,爱因斯坦的百年预言终获证实。空间引力波探测器使得探测0.1 m Hz~1 Hz频段丰富的引力波源成为可能,与地面引力波探测器互为补充,才可实现更加宽广波段的引力波探测,揭开宇宙早期的更多秘密。空间激光干涉引力波探测采用外差干涉测量技术,测量间距百万公里的两自由悬浮测试质量间10 pm量级的变化量。望远镜是激光干涉测量系统的重要组成部分,1 pm的光程稳定性及苛刻的杂散光要求,不同于传统的几何成像望远镜。本文根据空间太极计划任务需求,对望远镜的功能及技术要求进行了分析,并完成了原理样机的初步方案设计,针对百万公里远场波前分布,分析了望远镜系统的敏感性,同时完成了在轨光机热集成仿真,为后面原理样机的研制奠定了技术基础。 相似文献
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简述了引力波探测的历史,介绍了对质量谐振探测器、地面激光干涉引力波探测器、空间激光干涉引力波探测器,以及引力波在宇宙微波背景上极化效应的相关探测方案,评述了微波频带的高频引力波探测方案. 相似文献
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要察觉引力波的存在, Virgo (欧洲室女座天文台)和LIGO(美国激光干涉引力波天文台)需要能检测到激光干涉臂的微小改变——小到只有质子直径的万分之一.研究人员已经通过有效降低"技术"噪声(比如来自地震的扰动和电子设备的干扰),实现了如此灵敏的探测.此时探测器的噪声已经接近量子散粒噪声这个无法避免的基本限制.现在,... 相似文献
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元月美国LIGO(laser interferometer Gravitational Wave Observatory激光干涉引力波观测站)发布了一篇重要研究成果.他们宣布在对去年发生的宇宙珈玛射线爆跟踪观测过程中,未能发现引力波存在的证据.这一结果让很多对这次观测寄予厚望(发现引力波)的科学家感到失望. 相似文献
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Photon motion in a Michelson interferometer is re-analyzed in terms of both geometrical optics and wave optics.The classical paths of the photons in the background of a gravitational wave are derived from the Fermat principle,which is the same as the null geodesics in general relativity.The deformed Maxwell equations and the wave equations of electric fields in the background of a gravitational wave are presented in a flat-space approximation.Both methods show that even the envelope of the response of an interferometer depends on the frequency of a gravitational wave,but it is almost independent of the frequency of the mirror's vibrations. 相似文献
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W. Winkler K. Danzmann H. Grote M. Hewitson S. Hild J. Hough H. Lück M. Malec A. Freise K. Mossavi S. Rowan A. Rüdiger R. Schilling J.R. Smith K.A. Strain H. Ward B. Willke 《Optics Communications》2007,280(2):492-499
The optical layout of the interferometric gravitational wave detector GEO600 is described in detail. Criteria for the choice of the geometry of this power- and signal recycled interferometer are presented, including the beam shape inside the interferometer and the surface figure of the optical components. Light power limits for the present setup are discussed. In addition, the demands for the mode cleaners and their performance are given. 相似文献
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Biplab Bhawal 《Pramana》2004,63(4):645-662
The Caltech-MIT joint LIGO project is operating three long-baseline interferometers (one of 2 km and two of 4 km) in order
to unambiguously measure the infinitesimal displacements of isolated test masses which convey the signature of gravitational
waves from astrophysical sources. An interferometric gravitational wave detector like LIGO is a complex, non-linear, coupled,
dynamic system. This article summarizes various interesting design characteristics of these detectors and techniques that
were implemented in order to reach and maintain its operating condition. Specifically, the following topics are discussed:
(i) length sensing and control, (ii) alignment sensing and control and (iii) thermal lensing which changes the performance
and operating point of the interferometer as the input power to LIGO is increased. 相似文献
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Vacuum spacetimes endowed with two commuting spacelike Killing vector fields are considered. Subject to the hypothesis that there exists a shearfree null geodesic congruence orthogonal to the two-surface generated by the two commuting spacelike Killing vector fields,it is shown that, with a specific choice of null tetrad, the Newman-Penrose equations are reduced to an ordinary differential equation of Riccati type. fiom the consideration of this differential equation, exact solutions of the vacuum Einstein field equations with distribution valued Weyl curvature describing the propagation of gravitational impulsive and shock wave of variable polarization are then constructed. 相似文献
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Laser beam geometry variations such as beam jitter and frequency fluctuations are a critical source of noise in the output
signal of a laser interferometer gravitational wave detector. In order to minimise this noise a resonant vibration isolated
optical filter or mode-cleaner is required. For advanced gravitational wave detectors such a mode-cleaner is required to be
able to handle transmitted power ∼100 W, and an internal circulating power of 45 kW. This paper addresses the design requirements
of such a mode-cleaner. We characterise the mode-cleaner requirements and the effects of high laser power on the optics and
its consequence on the suppression of higher order modes. 相似文献
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The observation of GW150914 gave a new independent measurement of the luminosity distance of a gravitational wave event. In this paper, we constrain the anisotropy of the Universe by using gravitational wave events.We simulate hundreds of events of binary neutron star merger that may be observed by the Einstein Telescope. Full simulation of the production process of gravitational wave data is employed. We find that 200 binary neutron star merging events with the redshift in (0,1) observed by the Einstein Telescope may constrain the anisotropy with an accuracy comparable to that from the Union2.1 supernovae. This result shows that gravitational waves can be a powerful tool for investigating cosmological anisotropy. 相似文献
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Michael?Hohensee Shau-Yu?Lan Rachel?Houtz Cheong?Chan Brian?Estey Geena?Kim Pei-Chen?Kuan Holger?Müller
We study the use of atom interferometers as detectors for gravitational waves in the mHz–Hz frequency band, which is complementary
to planned optical interferometers, such as laser interferometer gravitational wave observatories (LIGOs) and the Laser Interferometer
Space Antenna (LISA). We describe an optimized atomic gravitational wave interferometric sensor (AGIS), whose sensitivity
is proportional to the baseline length to power of 5/2, as opposed to the linear scaling of a more conservative design. Technical
challenges are briefly discussed, as is a table-top demonstrator AGIS that is presently under construction at Berkeley. We
study a range of potential sources of gravitational waves visible to AGIS, including galactic and extra-galactic binaries.
Based on the predicted shot noise limited performance, AGIS should be capable of detecting type Ia supernovae precursors within
500 pc, up to 200 years beforehand. An optimized detector may be capable of detecting waves from RX J0806.3+1527. 相似文献
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The detection of gravitational waves by a cluster of satellites is considered. The detector is an optical interferometer formed of several satellites. The calculations for three spacecraft are given. The complete detector response to the monochromatic gravitational wave generated by a binary star is computed. 相似文献
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Andreas Freise Stefan Hild Kentaro Somiya Ken A. Strain Andrea Viceré Matteo Barsuglia Simon Chelkowski 《General Relativity and Gravitation》2011,43(2):537-567
The third generation of gravitational wave observatories, with the aim of providing 100 times better sensitivity than currently
operating interferometers, is expected to establish the evolving field of gravitational wave astronomy. A key element, required
to achieve this ambitious sensitivity goal, is the exploration of new interferometer geometries, topologies and configurations.
In this article we review the current status of the ongoing design work for third-generation gravitational wave observatories.
The main focus is the evaluation of the detector geometry and detector topology. In addition we discuss some promising detector
configurations and potential noise reduction schemes. 相似文献
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César H. Lenzi Nadja S. Magalhães César A. Costa Rubens M. Marinho Jr Helmo A. B. Araújo Odylio D. Aguiar 《General Relativity and Gravitation》2008,40(1):183-190
The direct detection of gravitational waves will provide valuable astrophysical information about many celestial objects.
Also, it will be an important test to general relativity and other theories of gravitation. The gravitational wave detector
SCHENBERG has recently undergone its first test run. It is expected to have its first scientific run soon. In this work the
data analysis system of this spherical, resonant mass detector is tested through the simulation of the detection of gravitational
waves generated during the inspiralling phase of a binary system. It is shown from the simulated data that it is not necessary
to have all six transducers operational in order to determine the source’s direction and the wave’s amplitudes. 相似文献