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      引力波

      2016-06-14 09:46:43
      中國學術期刊文摘 2016年7期
      關鍵詞:脈沖星引力波詞條

      ?

      引力波

      愛因斯坦于1916年提出了廣義相對論,根據(jù)廣義相對論,物理學家先后提出了4個預言,即光線在引力場中的偏折,光譜線在引力場中的紅移,引力波存在和黑洞存在。作為廣義相對論中最重要預言的引力波,由于其十分微弱,所以很難被探測到,一直以來都是物理學和天文學重點研究的對象。20世紀70年代,普林斯頓大學物理學家拉塞爾·赫爾斯和約瑟夫·泰勒觀測到一個脈沖星與另一個天體相互繞轉組成的雙星系統(tǒng),后來發(fā)現(xiàn)第二個天體是一個中子星。這個系統(tǒng)由于輻射引力波,導致脈沖星的軌道緩慢地縮小,觀測到的軌道變化率與相對論的預言高度一致,給出了引力波存在的第一個間接證據(jù)。2016年2月11日,激光干涉引力波天文臺(Laser Interferometer Gravitational Wave Observatory,簡稱LIGO)項目主管大衛(wèi)·萊茲在華盛頓舉行的新聞發(fā)布會上宣布人類首次直接探測到引力波的存在。相關論文發(fā)表在2016年2月11日在線出版的《Physical Review Letters》上。

      黑洞并合等天體物理過程產(chǎn)生的引力波還可以利用校準后的毫秒脈沖星、空間衛(wèi)星陣列等方式探測。此外還有一種尤為獨特的引力波,天文學家稱之為“原初引力波”。這種引力波產(chǎn)生于宇宙大爆炸的一瞬間,其波長跟整個宇宙的尺度差不多,所以只能通過宇宙微波背景輻射信號中留下的蛛絲馬跡來尋找原初引力波的信號。中國計劃在西藏阿里地區(qū)利用高海拔大氣高透過率的特點開展原初引力波的探測實驗。引力波的探測是當前物理學重要的前沿領域之一,有助于人類更加清楚地了解宇宙的起源和運行機制,為人類提供觀測宇宙的一個新窗口。

      本專題得到李芳昱教授(重慶大學物理學院)的大力支持。

      截至2016年2月29日,中國知網(wǎng)(CNKI)和Web of Science(WOS)的數(shù)據(jù)報告顯示,以“引力波”為詞條可以檢索到的期刊文獻分別為223與 4194條,本專題將相關數(shù)據(jù)按照:研究機構發(fā)文數(shù)、作者發(fā)文數(shù)、期刊發(fā)文數(shù)、被引用頻次進行排行,結果如下。

      研究機構發(fā)文數(shù)量排名(CNKI)    研究機構發(fā)文數(shù)量排名(WOS)

      作者發(fā)文數(shù)量排名(CNKI) 作者發(fā)文數(shù)量排名(WOS)

      期刊發(fā)文數(shù)量排名(CNKI)    期刊發(fā)文數(shù)量排名(WOS)

      根據(jù)中國知網(wǎng)(CNKI)數(shù)據(jù)報告,以“引力波”為詞條可以檢索到的高被引論文排行結果如下。

      國內數(shù)據(jù)庫高被引論文排行

      續(xù)表

      根據(jù)Web of Science統(tǒng)計數(shù)據(jù),以“引力波”為詞條可以檢索到的高被引論文排行結果如下。

      國外數(shù)據(jù)庫高被引論文排行

      基于Web of Science檢索結果,利用Histcite軟件選取LCS(Local Citation Score,本地引用次數(shù))TOP 30文獻作為節(jié)點進行分析,得到本領域推薦的經(jīng)典文獻如下。

      來源出版物:Physical Review, 1960, 117(1): 306-313

      Determining the hubble constant from gravitational-wave observations

      Schutz, BF Abstract: I report here how gravitational wave observations can be used to determine the Hubble constant, H0. The nearly monochromatic gravitational waves emitted

      by the decaying orbit of an ultra-compact, two-neutron-star binary system just before the stars coalesce are very likely to be detected by the kilometre- sized interferometric gravitational wave antennas now being designed. The signal is easily identified and contains enough information to determine the absolute distance to the binary, independently of any assumptions about the masses of the stars. Ten events out to 100 Mpc may suffice to measure the Hubble constant to 3% accuracy.

      來源出版物:Nature, 1986, 323(6086): 310-311

      The VIRGO Project: A wide band antenna for gravitational wave detection

      Bradaschia, C; Delfabbro, R; Divirgilio, A; et al.

      Abstract: The status of advancement of the VIRGO Project is presented: the first-generation results from the Pisa seismic noise super attenuator give an upper limit to the noise transfer function of 2×10ˉ8at 10 Hz. The upper limit to the absolute noise of the 400 kg test mass at 10 Hz has been measured to be 1.5×10ˉ13m/Hz. The scheme and the related problems of the VIRGO interferometer, which is supposed to work down to 10 Hz, are also presented. At the 3rd Pisa Meeting in 1986 we presented the idea of what could be a very efficient seismic noise reduction system able to give a sensitivity h~10ˉ25at 10 Hz, in a 3 km interferometer for 1 year integration time. Now we have two new facts to present: the first is that the attenuation has been built, is working in Pisa, and shows remarkable

      characteristics. The second is the Italian-French interferometer VIRGO, a 3 km long antenna for low and high frequency (10-1000 Hz) gravitational wave (GW) detection.

      來源出版物:Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1990, 289(3): 518-525

      The last 3 minutes: Issues in gravitational-wave measurements of coalescing compact binaries

      Cutler, C; Apostolatos, TA; Bildsten, L; et al.

      Abstract: Gravitational-wave interferometers are expected to monitor the last three minutes of inspiral and final coalescence of neutron star and black hole binaries at distances approach cosmological, where the event rate may be many per year. Because the binary's accumulated orbital phase can be measured to a fractional accuracy ? 10-3and relativistic effects axe large, the wave forms will be far more complex and carry more information than has been expected. Improved wave form modeling is needed as a foundation for extracting the waves’ information, but is not necessary for wave detection.

      來源出版物:Physical Review Letters, 1993, 70(20): 2984-2987

      Search templates for gravitational waves from inspiraling binaries: Choice of template spacing

      Owen, BJ Abstract: Gravitational waves from inspiraling, compact binaries will be searched for in the output of the LIGO-VIRGO interferometric network by the method of‘‘matched filtering’’—i.e., by correlating the noisy output of each interferometer with a set of theoretical wave form templates. These search templates will be a discrete subset of a continuous, multiparameter family, each of which approximates a possible signal. The search might be performed hierarchically, with a first pass through the data using a low threshold and a coarsely spaced, few-parameter template set, followed by a second pass on threshold-exceeding data segments, with a higher threshold and a more finely spaced template set that might have a

      larger number of parameters. Alternatively, the search might involve a single pass through the data using the larger threshold and finer template set. This paper extends and generalizes the Sathyaprakash-Dhurandhar (SD) formalism for choosing the discrete, finely spaced template set used in the final (or sole) pass through the data, based on the analysis of a single interferometer. The SD formalism is rephrased in geometric language by introducing a metric on the continuous template space from which the discrete template set is drawn. This template metric is used to compute the loss of signal-to-noise ratio and reduction of event rate which result from the coarseness of the template grid. Correspondingly, the template spacing and total number N of templates are expressed, via the metric, as functions of the reduction in event rate. The theory is developed for a template family of arbitrary dimensionality (whereas the original SD formalism was restricted to a single nontrivial dimension). The theory is then applied to a simple post1-Newtonian template family with two nontrivial dimensions. For this family, the number of templates N in the finely spaced grid is related to the spacing-induced fractional loss L of event rate and to the minimum mass Mmin of the least massive star in the binaries for which one searches by N~2×105(0.1/L) (0.2M⊙/Mmin)2.7for the first LIGO interferometers and by N~8×106(0.1/L)(0.2M⊙/Mmin)2.7for advanced LIGO interferometers. This is several orders of magnitude greater than one might have expected based on Sathyaprakash’s discovery of a near degeneracy in the parameter space, the discrepancy being due to that paper’s high choice of Mmin and less stringent choice of L. The computational power P required to process the steady stream of incoming data from a single interferometer through the closely spaced set of templates is given in floating-point operations per second by P~3×1010(0.1/L)(0.2M⊙/Mmin)2.7for the first LIGO interferometers and by P~4×1011(0.1/L) (0.2M⊙/Mmin)2.7for advanced LIGO interferometers. This will be within the capabilities of LIGO-era computers, but a hierarchical search may still be desirable to reduce the required computing power.

      來源出版物:Physical Review D, 1996, 53(12): 6749-6761

      Detection and generation of gravitational waves

      Weber, J

      Abstract:Methods are proposed for measurement of the Riemann tensor and detection of gravitational waves. These make use of the fact that relative motion of mass points, or strains in a crystal, can be produced by second derivatives of the gravitational fields. The strains in a crystal may result in electric polarization in consequence of the piezoelectric effect. Measurement of voltages then enables certain components of the Riemann tensor to be determined. Mathematical analysis of the limitations is given. Arrangements are presented for search for gravitational radiation. The generation of gravitational waves in the laboratory is discussed. New methods are proposed which employ electrically induced stresses in crystals. These give approximately a seventeen-order increase in radiation over a spinning rod of the same length as the crystal. At the same frequency the crystal gives radiation which is about thirty-nine orders greater than that of a spinning rod.

      文獻編號本領域經(jīng)典文章題目第一作者來源出版物1 Detection and generation of gravitational waves Weber, J Physical Review, 1960, 117(1): 306-313 2 Determining the hubble constant from gravitational-wave observations Schutz, BF Nature, 1986, 323(6086): 310-311 3The VIRGO Project: A wide band antenna for gravitational wave detection Bradaschia, C Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment , 1990, 289(3): 518-525 4 The last 3 minutes: Issues in gravitational-wave measurements of coalescing compact binaries Cutler, C Physical Review Letters, 1993, 70(20): 2984-2987 5 Search templates for gravitational waves from inspiraling binaries: Choice of template spacing Owen, BJ Physical Review D, 1996, 53(12): 6749-6761

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