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Measurement and Analysis of Vibration Effect of Free-falling Corner Cube Driving Mechanism in Free Fall Absolute Gravimeter
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作者 ZHANG Bing ZHU Xiaoyi +7 位作者 WU Qiong XUE Bing XING Lili WU Yanxiong SU Peng WANG Xiaolei WANG Yuru WANG Chuhan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期84-86,共3页
The vibration interference of the reference corner cube runs through the free flight process of the free-falling corner cube,which is superimposed on the whole laser interference fringes.Thus,it is necessary to solve ... The vibration interference of the reference corner cube runs through the free flight process of the free-falling corner cube,which is superimposed on the whole laser interference fringes.Thus,it is necessary to solve the interference fringes with the entire fringe to analyze the quantitative influence of vibration on gravity measurements. 展开更多
关键词 laser interference absolute gravimeter gravity measurement vibration influence
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First acceptance testing of multiple A10 absolute gravimeters in China and analysis of the comparison results 被引量:2
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作者 Xiaotong Zhang Hao Zhou +4 位作者 Ying Jiang Dulin Zhai Gongzhe Wei Hui Li Ziwei Liu 《Geodesy and Geodynamics》 EI CSCD 2023年第4期401-410,共10页
Three A10 absolute gravimeters(AGs) were first acquired in China by the Hubei Earthquake Agency under the Belt and Road Seismic Monitoring Network Project. Although AG measuring and testing technique is not new, the p... Three A10 absolute gravimeters(AGs) were first acquired in China by the Hubei Earthquake Agency under the Belt and Road Seismic Monitoring Network Project. Although AG measuring and testing technique is not new, the purchase and simultaneous testing of 3 A10 absolute gravimeters is unprecedented in China. This study conducted the first acceptance testing of the AGs at 3 locations(the Jiufengshan Gravity Observation Station, the Global Navigation Satellite System Observation Station in Wuhan, and the Jiugongshan Observation Station in Xianning). The results were compared using a method based on expert validation, and the acceptance testing scheme was formulated by referring to the Technical Regulations for Tectonic Environment Monitoring Networks in China and Specifications for Gravimetry Control. Based on the repeatability, precision, and consistency of the measured g values, the results from each instrument were evaluated using the air pressure precision test. Comparing the instrument reference values, the final test results can identify the indicator parameters for 3 A10 AGs, the effects of the surrounding environment, and the related parameters on measurement precision. The precision of A10-059, A10-058, and A10-057 exceeded 0.78 μGal, 0.79 μGal, and 0.42 μGal, respectively.This testing scheme can be used as a reference for conducting acceptance testing of AGs in the future and obtaining absolute gravimetric measurements. 展开更多
关键词 Gravitational acceleration Comparison of absolute gravimeters A10 absolute gravimeters Instrument precision
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A marine gravimeter based on electromagnetic damping and its tests in the South China Sea 被引量:1
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作者 Pengfei WU Lin WU +3 位作者 Lifeng BAO Long WANG Bo WANG Danling TANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第2期792-803,共12页
A new gravity sensor based on electromagnetic damping for the JMGrav marine gravimeter is presented.The new gravity sensor considered the advanced construction methods of the electromagnetic damping system of the grav... A new gravity sensor based on electromagnetic damping for the JMGrav marine gravimeter is presented.The new gravity sensor considered the advanced construction methods of the electromagnetic damping system of the gravimeter.The design features of the new system are discussed and the research survey data in the South China Sea are shown.Numerical simulations are applied to model the magnetic and mechanical characteristics of the system using finite element analysis and to evaluate the force distribution and the resulting damping effects.The performance characteristics of the system were tested on a motion simulator in laboratory,and the gravimeter was subjected to vertical accelerations of up to 100 Gal in 1-1000 s.It was found that the amplitude reduction of vertical accelerations in 3-15 s is 30-45 dB,with a time lag of 2-5 s,while the effect on gravity in period greater than 600 s is less than 0.5 dB,with a time lag of less than 100 s.The accelerations cause discrepancies of approximately only 1 mGal between the static value and the mean dynamic value.The sea tests were conducted in September 2020.Gravity measurements were taken with a JMGrav marine gravimeter onboard the R/V Dongfanghong 3,and the effective survey line exceeded 2000 km.Completely irregular accelerations with peaks up to 100 Gal yielded a reduction of approximately 40 dB in amplitude.The survey data were evaluated using ocean gravity field models and grid line tests.The results show that the accuracy of the gravity measurements is better than 2 mGal. 展开更多
关键词 electromagnetic damping JMGrav marine gravimeter marine gravity survey
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Optimal zero-crossing group selection method of the absolute gravimeter based on improved auto-regressive moving average model
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作者 牟宗磊 韩笑 胡若 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期347-354,共8页
An absolute gravimeter is a precision instrument for measuring gravitational acceleration, which plays an important role in earthquake monitoring, crustal deformation, national defense construction, etc. The frequency... An absolute gravimeter is a precision instrument for measuring gravitational acceleration, which plays an important role in earthquake monitoring, crustal deformation, national defense construction, etc. The frequency of laser interference fringes of an absolute gravimeter gradually increases with the fall time. Data are sparse in the early stage and dense in the late stage. The fitting accuracy of gravitational acceleration will be affected by least-squares fitting according to the fixed number of zero-crossing groups. In response to this problem, a method based on Fourier series fitting is proposed in this paper to calculate the zero-crossing point. The whole falling process is divided into five frequency bands using the Hilbert transformation. The multiplicative auto-regressive moving average model is then trained according to the number of optimal zero-crossing groups obtained by the honey badger algorithm. Through this model, the number of optimal zero-crossing groups determined in each segment is predicted by the least-squares fitting. The mean value of gravitational acceleration in each segment is then obtained. The method can improve the accuracy of gravitational measurement by more than 25% compared to the fixed zero-crossing groups method. It provides a new way to improve the measuring accuracy of an absolute gravimeter. 展开更多
关键词 absolute gravimeter laser interference fringe Fourier series fitting honey badger algorithm mul-tiplicative auto-regressive moving average(MARMA)model
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Data Quality Control Method of a New Drifting Observation Technology Named Drifting Air-Sea Interface Buoy
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作者 LI Shuo WANG Bin +3 位作者 DENG Zeng’an WU Baoqin ZHU Xiande CHEN Zhaohui 《Journal of Ocean University of China》 CAS CSCD 2024年第1期11-22,共12页
An integral quality control(QC)procedure that integrates various QC methods and considers the design indexes and operational status of the instruments for the observations of drifting air-sea interface buoy was develo... An integral quality control(QC)procedure that integrates various QC methods and considers the design indexes and operational status of the instruments for the observations of drifting air-sea interface buoy was developed in the order of basic in-spection followed by targeted QC.The innovative method of combining a moving Hampel filter and local anomaly detection com-plies with statistical laws and physical processes,which guarantees the QC performance of meteorological variables.Two sets of observation data were used to verify the applicability and effectiveness of the QC procedure,and the effect was evaluated using the observations of the Kuroshio Extension Observatory buoy as the reference.The results showed that the outliers in the time series can be correctly identified and processed,and the quality of data improved significantly.The linear correlation between the quality-controlled observations and the reference increased,and the difference decreased.The correlation coefficient of wind speed before and after QC increased from 0.77 to 0.82,and the maximum absolute error decreased by approximately 2.8ms^(-1).In addition,air pressure and relative humidity were optimized by 10^(-3)–10^(-2) orders of magnitude.For the sea surface temperature,the weight of coefficients of the continuity test algorithm was optimized based on the sea area of data acquisition,which effectively expanded the applicability of the algorithm. 展开更多
关键词 drifting air-sea interface buoy quality control oceanic variables meteorological variables continuity test
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Observing the air-sea turbulent heat flux on the trajectory of tropical storm Danas
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作者 Xuehan XIE Xiangzhou SONG +3 位作者 Marilena OLTMANNS Yangang LI Qifeng QIAN Zexun WEI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第5期1425-1437,共13页
Tropical cyclones constitute a major risk for coastal communities.To assess their damage potential,accurate predictions of their intensification are needed,which requires a detailed understanding of the evolution of t... Tropical cyclones constitute a major risk for coastal communities.To assess their damage potential,accurate predictions of their intensification are needed,which requires a detailed understanding of the evolution of turbulent heat flux(THF).By combining multiple buoy observations along the south north storm track,we investigated the THF anomalies associated with tropical storm Danas(2019)in the East China Sea(ECS)during its complete life cycle from the intensification stage to the mature stage and finally to its dissipation on land.The storm passage is characterized by strong winds of 10-20 m/s and a sea level pressure below 1000 hPa,resulting in a substantial enhancement of THF.Latent heat(LH)fluxes are most strongly affected by wind speed,with a gradually increasing contribution of humidity along the trajectory.The relative contributions of wind speed and temperature anomalies to sensible heat(SH)depend on the stability of the boundary layer.Under stable conditions,SH variations are driven by wind speed,while under near-neutral conditions,SH variations are driven by temperature.A comparison of the observed THF and associated variables with outputs from the ERA 5 and MERRA 2 reanalysis products reveals that the reanalysis products can reproduce the basic evolution and composition of the observed THF.However,under extreme weather conditions,temperature and humidity variations are poorly captured by ERA 5 and MERRA 2,leading to large LH and SH errors.The differences in the observed and reproduced LH and SH during the passage of Danas amount to 26.1 and 6.6 W/m^(2) for ERA 5,respectively,and to 39.4 and 12.5 W/m^(2) for MERRA 2,respectively.These results demonstrate the need to improve the representation of tropical cyclones in reanalysis products to better predict their intensification process and reduce their damage. 展开更多
关键词 tropical cyclone(TC) air-sea turbulent heat flux(THF) latent heat flux sensible heat flux buoy observation reanalysis product
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Joint observation of long period tremor signals with broadband seismometer,tiltmeter and gravimeter 被引量:25
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作者 张雁滨 蒋骏 +2 位作者 廖盈春 李胜乐 钟铁涛 《地震学报》 CSCD 北大核心 2008年第6期626-633,共8页
We report here the observation result of joint observation of long period tremor signals with broadband seismome-ter,tiltmeter and gravimeter at the HUST(Huazhong University of Science and Technology)station.The obser... We report here the observation result of joint observation of long period tremor signals with broadband seismome-ter,tiltmeter and gravimeter at the HUST(Huazhong University of Science and Technology)station.The observed data were compared and analyzed.Since 2005,the several tens of abnormal tremor signals which are weak,com-plex and duration of 2 to 3 days have been synchronously recorded by the different instruments.The tremor signals have the periodic domain in the range of 3 to 5 minutes,20 to 30 minutes and even more than 1 hour.The observa-tion shows such tremors are a physical existence.The analysis indicates that a part of the tremors caused by the typhoon from the western Pacific Ocean.These tremors have a close relationship with wind velocity of typhoon and distance between the typhoon center and the station.Except these,the cause of others is still unclear. 展开更多
关键词 宽频地震观测 重力观测 倾斜观测 长周期信号 震颤 台风
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Scintrex CG5 used for superconducting gravimeter calibration 被引量:6
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作者 Bruno Meurers 《Geodesy and Geodynamics》 2018年第3期197-203,共7页
The scale factor accuracy of superconducting gravimeters (SG) can be largely improved by a high repetition rate of calibration experiments. At stations where the availability of absolute gravimeters is limited, care... The scale factor accuracy of superconducting gravimeters (SG) can be largely improved by a high repetition rate of calibration experiments. At stations where the availability of absolute gravimeters is limited, carefully calibrated spring gravimeters can be used for providing the reference signal assuming the irregular drift is properly adjusted. The temporal stability of the SG scale factor is assessable by comparing the temporal variations of M2 tidal parameters observed at neighboring SG sites or from synthetic tide models. Combining these methods reduces the SG scale factor error to a few 0.1%0. The paper addresses the particular procedure required for evaluating the calibration experiments based on spring gravimeters and presents results obtained at Conrad observatory (Austria). Comparing the M2 amplitude factor modulation helped to reveal a SG scale factor offset of about 0.2%0 due to re-installation. 展开更多
关键词 Superconducting gravimeter CG-5 Scintrex gravimeterScale factor Calibration accuracy M2 tidal parameter variation
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Comparison of noise-levels between superconducting gravimeter and gPhone gravimeter 被引量:4
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作者 Kun Zhang Ziwei Liu +1 位作者 Xiaotong Zhang Ying Jiang 《Geodesy and Geodynamics》 2018年第6期498-503,共6页
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关键词 Superconducting gravimeter gPhone gravimeter Noise level SNM SSNM
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Calibration of the superconducting gravimeter based on a cold atom absolute gravimeter at NIM 被引量:1
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作者 Qiyu Wang Jinyang Feng +4 位作者 Shaokai Wang Wei Zhuang Yang Zhao Lishuang Mou Shuqing Wu 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第12期250-255,共6页
The scale factor of a superconducting gravimeter(SG) is usually calibrated by using simultaneous and co-located gravity measurements with the FG5-type absolute gravimeter(AG). In this paper, another new kind of absolu... The scale factor of a superconducting gravimeter(SG) is usually calibrated by using simultaneous and co-located gravity measurements with the FG5-type absolute gravimeter(AG). In this paper, another new kind of absolute gravimetercold atom gravimeter(CAG) is first reported to calibrate the SG. Five-day side-by-side gravity measurements have been carried out by using our CAG(NIM-AGRb-1) to calibrate the SG(iGrav-012) located at Changping Campus of the National Institute of Metrology(NIM) of China. A weighted least-squares method is applied to determine the scale factor and the result is given as(-928.01 ± 0.73) nm·s^(-2)·V^(-1) with a precision of 0.79‰. We have demonstrated that a calibration precision of 1‰ level can be achieved after 3 days of parallel observations at spring tide. The obtained calibration results are then compared with the previous calibration by FG5 X-249, which shows that the calibration precision obtained by using NIM-AGRb-1 was slightly higher than FG5 X-249 with the same time interval. The factors affecting the calibration precision are analyzed in the calibrations by means of different AGs. Finally, several calibration experiments for SG iGrav-012 are discussed. The final scale factor is estimated as(-927.58 ± 0.36) nm·s^(-2)·V^(-1) with an accuracy of 0.39‰. Our main results demonstrate that the CAGs can be used for high-precision calibrations of SGs. 展开更多
关键词 cold atom gravimeter CALIBRATION superconducting gravimeter scale factor
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Accurate determination of calibration factor for tidal gravity observation of a GWR-superconducting gravimeter 被引量:1
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作者 孙和平 陈晓东 +1 位作者 许厚泽 王勇 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2001年第6期692-700,共9页
It is recognized widely nowadays that the superconducting gravimeter (SG) is a kind of best relative gravimeter with high observing precision, good continuity and stability. However, it is necessary to calibrate the d... It is recognized widely nowadays that the superconducting gravimeter (SG) is a kind of best relative gravimeter with high observing precision, good continuity and stability. However, it is necessary to calibrate the direct output (change in voltage) by using scale value (calibration factor) before getting the change of the real gravity field. Studies show that the accuracy of the scale value will influence the late analysis and explanation of the observations. By using absolute gravity measurements of a FG5 absolute gravimeter (AG) at Wuhan international tidal gravity fundamental station (two campaigns each for 3 days) and by using known tidal parameters at the same station, the calibration factors of the SG and their precision are studied in detail in this paper. 展开更多
关键词 superconducting gravimeter absolute gravimeter tidal observation calibration factor preci-sion analysis
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Calibration of a compact absolute atomic gravimeter 被引量:6
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作者 Hong-Tai Xie Bin Chen +3 位作者 Jin-Bao Long Chun Xue Luo-Kan Chen Shuai Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第9期84-91,共8页
Compact atomic gravimeters are the potential next generation precision instruments for gravity survey from fundamental research to broad field applications.We report the calibration results of our home build compact a... Compact atomic gravimeters are the potential next generation precision instruments for gravity survey from fundamental research to broad field applications.We report the calibration results of our home build compact absolute atomic gravimeter USTC-AG02 at Changping Campus,the National Institute of Metrology(NIM),China in January 2019.The sensitivity of the atomic gravimeter reaches 35.5μGal/√Hz(1μGal=1×10-8 m/s2)and its long-term stability reaches 0.8μGal for averaging over 4000 seconds.Considering the statistical uncertainty,the dominant instrumental systematic errors and environmental effects are evaluated and corrected within a total uncertainty(2σ)of 15.3μGal.After compared with the reference g value given by the corner cube gravimeter NIM-3A,the atomic gravimeter USTC-AG02 reaches the degree of equivalence of 3.7μGal. 展开更多
关键词 atom interferometry absolute gravimeter systematic errors
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The influence of observation environment on background noise level of gPhone gravimeter 被引量:6
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作者 Xiaotong Zhang Ying Jiang +1 位作者 Kun Zhang Xinlin Zhang 《Geodesy and Geodynamics》 2017年第6期443-447,共5页
Based on the observations of 36 gPhone gravimeters in 2015, the background noise levels in the seismic frequency band(200-600 s) and sub-seismic band(1-6 h) are calculated. The differences in the PSD(power spectr... Based on the observations of 36 gPhone gravimeters in 2015, the background noise levels in the seismic frequency band(200-600 s) and sub-seismic band(1-6 h) are calculated. The differences in the PSD(power spectrum density) of each band of gPhone gravimetric gauges in different surrounding environments were analyzed and compared with Peterson's NLNM(new low-noise model) which is derived from the envelope at the power spectrum density of 75 seismograph stations around the world. The results showed that: the influence of station type on the noise magnitude of gPhone gravimeter is very small; The seismic band noise magnitude(hereinafter referred to as SNM) and the sub-seismic band noise magnitude(hereinafter referred to as SSNM) in the coastal gPhone gravimeter are higher than those of inland stations. Although the local hydrological change has a great influence on the gravity observation, the rainfall is not directly relative to the noise magnitude of the instrument. Except 3 coastal stations, the eight stations which had the highest amplitudes in the SNM were located near the seismic belt. This indicates that the SNM of the gPhone Gravimeter may reflect some seismic information.Compared with the NLNM model, the PSD of the gPhone gravimeter is lower than the NLNM model in the long period band(〈3×10^(-5)Hz), indicating that the gPhone gravimeter is more suitable for detecting long-period signals(〉10 h) than the seismometer. 展开更多
关键词 gPhone gravimeter Background noise level NLNM Observation environment
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Investigation of the thermal adaptability for a mobile cold atom gravimeter 被引量:1
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作者 王启宇 王兆英 +1 位作者 付志杰 林强 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第12期241-246,共6页
The cold atom gravimeter offers the prospect of a new generation of inertial sensors for field applications. We ac- complish a mobile atom gravimeter. With the compact and stable system, a sensitivity of 1.4× 10-... The cold atom gravimeter offers the prospect of a new generation of inertial sensors for field applications. We ac- complish a mobile atom gravimeter. With the compact and stable system, a sensitivity of 1.4× 10-7 g.Hz-1/2 is achieved. Moreover, a continuous gravity monitoring of 80 h is carried out. However, the harsh outdoor environment is a big challenge for the atom gravimeter when it is for field applications. In this paper, we present the preliminary investigation of the thermal adaptability for our mobile cold atom gravimeter. Here, we focus on the influence of the air temperature on the performance of the atom gravimeter. The responses to different factors (such as laser power, fiber coupling efficiency, etc.) are evaluated when there is a great temperature shift of 10 ℃. The result is that the performances of all the factors deteriorate to different extent, nevertheless, they can easily recover as the temperature comes back. Finally, we conclude that the variation of air temperature induces the increase of noise and the system error of the atom gravimeter as well, while the process is reversible with the recovery of the temperature. 展开更多
关键词 atom gravimeter the environmental adaptability atom intefferometer
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Far-field coseismic gravity changes related to the 2015 MW7.8 Nepal(Gorkha)earthquake observed by superconducting gravimeters in Chinese mainland 被引量:5
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作者 LeLin Xing ZiWei Liu +3 位作者 JianGang Jia ShuQing Wu ZhengSong Chen XiaoWei Niu 《Earth and Planetary Physics》 CSCD 2021年第2期141-148,共8页
Using data from five SGs at four stations in Chinese mainland,obvious permanent gravity changes caused by the 2015 MW7.8 Nepal(Gorkha)earthquake were detected.We analyzed the gravity effects from ground vertical defor... Using data from five SGs at four stations in Chinese mainland,obvious permanent gravity changes caused by the 2015 MW7.8 Nepal(Gorkha)earthquake were detected.We analyzed the gravity effects from ground vertical deformation(VD)using co-site continuous GPS(cGPS)data collocated at the Lijiang and the Wuhan station,and hydrological effects using GLDAS models and groundwater level records.After removing these effects,SG observations before and after the earthquake revealed obvious permanent gravity changes:−3.0μGal,7.3μGal and 8.0μGal at Lhasa,Lijiang and Wuhan station,respectively.We found that the gravity changes cannot be explained by the results of dislocation theory. 展开更多
关键词 the 2015 Nepal earthquake superconducting gravimeter coseismic gravity change
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Estimated Green's function extracted from superconducting gravimeters and seismometers 被引量:1
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作者 Xiangfang Zeng Zhongwen Zhan Yong Zheng 《Earthquake Science》 CSCD 2011年第2期143-150,共8页
Estimated Green’s function (EGF) between stations has been extracted from ambient seismic noise, direct surface wave and coda waves. It is also confirmed by laboratory experiments on ultrasonics and theoretical der... Estimated Green’s function (EGF) between stations has been extracted from ambient seismic noise, direct surface wave and coda waves. It is also confirmed by laboratory experiments on ultrasonics and theoretical derivations assuming diffusive wave field, equi-partition of modes or random sources on an enclosed surface. This method provides a new approach to study the crust and mantle structure at regional scale, continental scale and global scale. Following the achievements with seismometer records, the records of infrasonic station, hydrophone and microphone were also used to obtain the EGFs of different wave fields. Since superconducting gravimeter is a better long period instrument than regular seismometer, EGF at longer period is expected to be obtained with the cross correlation of gravity data. In this paper, we will show the EGFs extracted by cross-correlations between the superconducting gravimeters and the seismometers. Both the travel times and dispersion curves obtained from different data types are consistent. The result shows that it is possible to retrieve the deep structure by the cross correlation of gravity data. 展开更多
关键词 superconducting gravimeter noise cross-correlation estimated Green’s function
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Movable precision gravimeters based on cold atom interferometry 被引量:2
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作者 Jiong-Yang Zhang Le-Le Chen +5 位作者 Yuan Cheng Qin Luo Yu-Biao Shu Xiao-Chun Duan Min-Kang Zhou Zhong-Kun Hu 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第9期70-78,共9页
High precision atom interferometers have shown attractive prospects in laboratory for testing fundamental physics and inertial sensing.Efforts on applying this innovative technology to field applications are also bein... High precision atom interferometers have shown attractive prospects in laboratory for testing fundamental physics and inertial sensing.Efforts on applying this innovative technology to field applications are also being made intensively.As the manipulation of cold atoms and related matching technologies mature,inertial sensors based on atom interferometry can be adapted to various indoor or mobile platforms.A series of experiments have been conducted and high performance has been achieved.In this paper,we will introduce the principles,the key technologies,and the applications of atom interferometers,and mainly review the recent progress of movable atom gravimeters. 展开更多
关键词 atom interferometer absolute gravimeter precision measurement
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Least Squares Spectral Analysis and Its Application to Superconducting Gravimeter Data Analysis 被引量:2
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作者 YINHui SpirosD.Pagiatakis 《Geo-Spatial Information Science》 2004年第4期279-283,共5页
Detection of a periodic signal hidden in noise is the goal of Superconducting Gravimeter (SG) data analysis. Due to spikes, gaps, datum shrifts (offsets) and other disturbances, the traditional FFT method shows inhere... Detection of a periodic signal hidden in noise is the goal of Superconducting Gravimeter (SG) data analysis. Due to spikes, gaps, datum shrifts (offsets) and other disturbances, the traditional FFT method shows inherent limitations. Instead, the least squares spectral analysis (LSSA) has showed itself more suitable than Fourier analysis of gappy, unequally spaced and unequally weighted data series in a variety of applications in geodesy and geophysics. This paper reviews the principle of LSSA and gives a possible strategy for the analysis of time series obtained from the Canadian Superconducting Gravimeter Installation (CGSI), with gaps, offsets, unequal sampling decimation of the data and unequally weighted data points. 展开更多
关键词 least squares spectrum superconducting gravimeter data analysis
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Michelson laser interferometer-based vibration noise contribution measurement method for cold atom interferometry gravimeter 被引量:1
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作者 Ning Zhang Qingqing Hu +4 位作者 Qian Wang Qingchen Ji Weijing Zhao Rong Wei Yuzhu Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第7期85-91,共7页
The measurement performance of the atom interferometry absolute gravimeter is strongly affected by the ground vibration noise.We propose a vibration noise evaluation scheme using a Michelson laser interferometer const... The measurement performance of the atom interferometry absolute gravimeter is strongly affected by the ground vibration noise.We propose a vibration noise evaluation scheme using a Michelson laser interferometer constructed by the intrinsic Raman laser of the atomic gravimeter.Theoretical analysis shows that the vibration phase measurement accuracy is better than 4 mrad,which corresponds to about 10-^10 g accuracy for a single shot gravity measurement.Compared with the commercial seismometer or accelerometer,this method is a simple,low cost,direct,and fully synchronized measurement of the vibration phase which should benefit the development of the atomic gravimeter.On the other side,limited by equivalence principle,the result of the laser interferometer is not absolute but relative vibration measurement.Triangular cap method could be used to evaluation the noise contribution of vibration,which is a different method from others and should benefit the development of the atomic gravimeter. 展开更多
关键词 atomic gravimeter Raman laser vibration monitoring
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A high-precision borehole gravimeter
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作者 Li Jiaming Yao Zhigui +2 位作者 Wen Xingwei Gong Ping Wei Jin 《Geodesy and Geodynamics》 2011年第3期76-79,共4页
The paper describes the working principle and structure of a newly designed high-precision ( inicrogal) gravimeter, which is basically a vertically suspending spring-weight system, using a highly sensitive capacitan... The paper describes the working principle and structure of a newly designed high-precision ( inicrogal) gravimeter, which is basically a vertically suspending spring-weight system, using a highly sensitive capacitance sensor of movement in a controlled temperature environment in a borehole and a multi-frequency output for both earth-tide and earthquake monitoring. The preliminary test indicated that, while in a stabilization process, it had met all the technical requirements for a relative gravimeter used for earth tide and earthquake monitoring. 展开更多
关键词 borehole gravimeter working principle STRUCTURE broad band
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