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Proceedings of Conference on Precision Electromagnetic Measurements Digest最新文献

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Proton/electron mass ratio and the electron's "atomic mass" 质子/电子质量比和电子的“原子质量”
Proceedings of Conference on Precision Electromagnetic Measurements Digest Pub Date : 1994-12-31 DOI: 10.1109/CPEM.1994.333166
R. V. Van Dyck, D. Farnham, P. Schwinberg
{"title":"Proton/electron mass ratio and the electron's \"atomic mass\"","authors":"R. V. Van Dyck, D. Farnham, P. Schwinberg","doi":"10.1109/CPEM.1994.333166","DOIUrl":"https://doi.org/10.1109/CPEM.1994.333166","url":null,"abstract":"Summary form only given. The heart of the Penning trap mass spectrometer (PTMS) is a well-machined, quadrupole trap with hyperbolic surfaces of revolution formed about a common axis of symmetry. Equally as important from the point of view of precision, a strong magnetic field, aligned along this trap axis, must be highly stable and uniform. For our present solenoid, the long term drift is /spl sim/0.1-0.3 ppb/h and short-term fluctuations are <1 ppb. We are now using a quite uniform magnetic field (with B/sub 2/<2 G/cm/sup 2/). Also, a significant improvement in the X-band microwave system (multiplied up to 160 GHz) now allows us to use the relativistic mass shift (equivalent to /spl sim/-10 G/cm/sup 2/) in order to observe the electron's cyclotron frequency with a precision of /spl plusmn/5 ppb per measurement and with systematics that are expected to be at least an order of magnitude less than that obtained in our previous work. The comparison ion in this case is a fully stripped carbon atom such that the electron's atomic mass can be directly determined upon correcting for lost electrons and their binding energies. At the present time, our typical single measurement precision for the C/sup 6+/ cyclotron frequency is about /spl plusmn/1 ppb which yields a relative precision on the order of 0.2 ppb after a 24-h data-period. Altogether, the typical measurement precision of the electron/carbon comparison now exceeds 1 ppb (using about 100 h of data). To obtain m/sub p//m/sub e/, a comparison is made with the proton's atomic mass which has an accepted value with an accuracy of 0.5 ppb. Thus, an improvement in this important fundamental constant is expected to be an order of magnitude, limited only by our estimate of residual systematics.<<ETX>>","PeriodicalId":388647,"journal":{"name":"Proceedings of Conference on Precision Electromagnetic Measurements Digest","volume":"2010 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125609896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 10
The IMGC volume-density standards for the Avogadro constant 阿伏伽德罗常数的IMGC体积密度标准
Proceedings of Conference on Precision Electromagnetic Measurements Digest Pub Date : 1994-12-31 DOI: 10.1109/CPEM.1994.333194
A. Sacconi, A. Peuto, M. Mosca, R. Panciera, W. Pasin, S. Pettorruso
{"title":"The IMGC volume-density standards for the Avogadro constant","authors":"A. Sacconi, A. Peuto, M. Mosca, R. Panciera, W. Pasin, S. Pettorruso","doi":"10.1109/CPEM.1994.333194","DOIUrl":"https://doi.org/10.1109/CPEM.1994.333194","url":null,"abstract":"Within the project for the determination of the Avogadro constant, the IMGC has developed volume-density standards in the form of single-crystal silicon spheres. In addition to a first sphere previously characterised and intercompared with a similar artifact, a new sphere of nearly perfect form is now available. The absolute determination of its mass and volume is presented together with the expected improvements in the assignment of a density value to high-purity and near-perfect silicon single-crystals.<<ETX>>","PeriodicalId":388647,"journal":{"name":"Proceedings of Conference on Precision Electromagnetic Measurements Digest","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127959642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 22
Trapping and laser cooling of Ca/sup +/ ions toward future optical frequency standards: observation of clock transitions 面向未来光学频率标准的Ca/sup +/离子的俘获和激光冷却:时钟跃迁的观察
Proceedings of Conference on Precision Electromagnetic Measurements Digest Pub Date : 1994-12-31 DOI: 10.1109/CPEM.1994.333230
S. Urabe, K. Hayasaka, M. Watanabe, H. Imajo, R. Ohmukai
{"title":"Trapping and laser cooling of Ca/sup +/ ions toward future optical frequency standards: observation of clock transitions","authors":"S. Urabe, K. Hayasaka, M. Watanabe, H. Imajo, R. Ohmukai","doi":"10.1109/CPEM.1994.333230","DOIUrl":"https://doi.org/10.1109/CPEM.1994.333230","url":null,"abstract":"Experimental results of trapping and laser cooling of Ca/sup +/ ions for future optical frequency standards are reported. Ca/sup +/ ions were trapped and laser-cooled to below 1 K. To observe the electric-quadrupole-allowed transitions (clock transitions), the laser diode operated at low temperature was developed. With this laser, the clock transitions were observed using the shelved electron double resonance method.<<ETX>>","PeriodicalId":388647,"journal":{"name":"Proceedings of Conference on Precision Electromagnetic Measurements Digest","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117101666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Dielectric properties of materials at cryogenic temperatures and microwave frequencies 材料在低温和微波频率下的介电特性
Proceedings of Conference on Precision Electromagnetic Measurements Digest Pub Date : 1994-12-31 DOI: 10.1109/CPEM.1994.333364
R. Geyer, J. Krupka
{"title":"Dielectric properties of materials at cryogenic temperatures and microwave frequencies","authors":"R. Geyer, J. Krupka","doi":"10.1109/CPEM.1994.333364","DOIUrl":"https://doi.org/10.1109/CPEM.1994.333364","url":null,"abstract":"The permittivity and dielectric loss tangent of single-crystal quartz, cross-linked polystyrene (Rexolite), and polytetrafluoroethylene (Teflon) were measured at microwave frequencies and at temperatures of 77 K and 300 K using a dielectric resonator technique. Application of high-temperature superconducting (HTS) films as the endplates of the dielectric resonator made it possible to determine dielectric loss tangents of about 7/spl times/10/sup 6/ at 77 K. Two permittivity tensor components for uniaxially anisotropic crystalline quartz were measured. Although the permittivities at 77 K changed very little from their room temperature values at 300 K, large changes in dielectric losses were observed. The decreased loss characteristics of these microelectronic substrates can markedly improve the performance of many microwave devices at cryogenic temperatures.<<ETX>>","PeriodicalId":388647,"journal":{"name":"Proceedings of Conference on Precision Electromagnetic Measurements Digest","volume":"143 1-4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114045853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
High accuracy absolute laser powermeter calibrated over the whole range 在整个范围内校准的高精度绝对激光功率计
Proceedings of Conference on Precision Electromagnetic Measurements Digest Pub Date : 1994-12-31 DOI: 10.1109/CPEM.1994.333223
N. Miron, G. Korony, V. Velculescu
{"title":"High accuracy absolute laser powermeter calibrated over the whole range","authors":"N. Miron, G. Korony, V. Velculescu","doi":"10.1109/CPEM.1994.333223","DOIUrl":"https://doi.org/10.1109/CPEM.1994.333223","url":null,"abstract":"The main contribution to this laser powermeter is the capability of its detector to be electrically calibrated over the whole measuring range (0...100 W), with an accuracy better than 1%. This allows an improved accuracy in determining the second-order polynomial coefficients describing thermocouple electric response.<<ETX>>","PeriodicalId":388647,"journal":{"name":"Proceedings of Conference on Precision Electromagnetic Measurements Digest","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126192253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Intelsat two-way time transfer experiments between Japan, Korea and Taiwan 日本、韩国和台湾之间的国际通信卫星双向时间转移实验
Proceedings of Conference on Precision Electromagnetic Measurements Digest Pub Date : 1994-12-31 DOI: 10.1109/CPEM.1994.333283
B. Engelkemier, K. Imamura, F. Takahashi, T. Yoshino, N. S. Chung, C. Liao
{"title":"Intelsat two-way time transfer experiments between Japan, Korea and Taiwan","authors":"B. Engelkemier, K. Imamura, F. Takahashi, T. Yoshino, N. S. Chung, C. Liao","doi":"10.1109/CPEM.1994.333283","DOIUrl":"https://doi.org/10.1109/CPEM.1994.333283","url":null,"abstract":"This paper describes the first two-way time transfer experiments using Intelsat Ku-band-satellites in eastern Asia performed by Communications Research Laboratory (CRL: Japan), Korea Research Institute of Standard and Science (KRISS: Korea) and Telecommunication Laboratory (TL: Taiwan) in 1992. The experiments are based on the recommendation of Conference Generale des Poids et Mesures (CGPM) in 1987. Also they are based on the international cooperation program between CRL and KRISS, and institute-level cooperation between CRL and TL. The experiments attained the short-term precision better than 1 ns, which is much better than conventional GPS time transfer. Long-term precision was not so good as short-term one. We discuss the reasons of the long-term instabilities. We can also established the procedures to use Intelsat satellites under the support of Intelsat Headquarters and each countries' common carrier agents.<<ETX>>","PeriodicalId":388647,"journal":{"name":"Proceedings of Conference on Precision Electromagnetic Measurements Digest","volume":"161 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122626664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
GPS time precision enhancement between Telecommunication Laboratories, R.O.C. and Communication Research Laboratory, Japan 台湾电信实验室与日本通讯研究实验室之GPS时间精度提升
Proceedings of Conference on Precision Electromagnetic Measurements Digest Pub Date : 1994-12-31 DOI: 10.1109/CPEM.1994.333173
C.S. Liao, J.L. Shi, F. Takahashi
{"title":"GPS time precision enhancement between Telecommunication Laboratories, R.O.C. and Communication Research Laboratory, Japan","authors":"C.S. Liao, J.L. Shi, F. Takahashi","doi":"10.1109/CPEM.1994.333173","DOIUrl":"https://doi.org/10.1109/CPEM.1994.333173","url":null,"abstract":"We discuss how to reduce the GPS time transfer errors between the TL and CRL. A portable GPS receiver was used to measure the GPS instrumental time delay error of TL. The theory, the simulation results, and the experimental results of the GPS antenna position error correction were also discussed. Finally, we measured the ionosphere delay at the TL.<<ETX>>","PeriodicalId":388647,"journal":{"name":"Proceedings of Conference on Precision Electromagnetic Measurements Digest","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121291800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Measurements and analysis of the frequency stability of GPS Navstar clocks GPS导航星时钟频率稳定性的测量与分析
Proceedings of Conference on Precision Electromagnetic Measurements Digest Pub Date : 1994-12-31 DOI: 10.1109/CPEM.1994.333318
T. Mccaskill, M. Largay, O. J. Oaks, W. G. Reid, J. Buisson, H. E. Warren
{"title":"Measurements and analysis of the frequency stability of GPS Navstar clocks","authors":"T. Mccaskill, M. Largay, O. J. Oaks, W. G. Reid, J. Buisson, H. E. Warren","doi":"10.1109/CPEM.1994.333318","DOIUrl":"https://doi.org/10.1109/CPEM.1994.333318","url":null,"abstract":"Analysis of the frequency stability of Global Positioning System (GPS) on-orbit Navstar clocks is performed by the Naval Research Laboratory (NRL). Clock offsets for each Navstar clock are derived from smoothed pseudorange measurements collected as the Navstar space vehicle passes over the tracking station. The clock offsets are further smoothed and estimated at the time of closest approach (TCA) of the space vehicle over the tracking station. Analysis of more than 50 Navstar clocks by NRL shows that the majority of these clocks provide performance that exceeds the GPS frequency stability specification. This precision measurement technique is capable of determining one-day frequency stabilities of the Navstar GPS clocks to an accuracy of better than 1/spl times/10/sup -13/.<<ETX>>","PeriodicalId":388647,"journal":{"name":"Proceedings of Conference on Precision Electromagnetic Measurements Digest","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131370763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
An original passive device for on-wafer noise parameter measurement verification 一种原始的无源器件，用于晶圆上噪声参数测量验证
Proceedings of Conference on Precision Electromagnetic Measurements Digest Pub Date : 1994-12-31 DOI: 10.1109/CPEM.1994.333237
A. Boudiaf, C. Dubon-Chevallier, D. Pasquet
{"title":"An original passive device for on-wafer noise parameter measurement verification","authors":"A. Boudiaf, C. Dubon-Chevallier, D. Pasquet","doi":"10.1109/CPEM.1994.333237","DOIUrl":"https://doi.org/10.1109/CPEM.1994.333237","url":null,"abstract":"Using a thin film technology, we have designed and fabricated a new passive device for on-wafer noise parameter measurement verification. The main feature specifying this device is the same order of magnitude for input-output reflection coefficients and for noise parameters, as for low noise MESFET or HEMT transistors. This new device is ideal as a verification standard, and suited for on-wafer measurements due to its small size and wide operation bandwidth.<<ETX>>","PeriodicalId":388647,"journal":{"name":"Proceedings of Conference on Precision Electromagnetic Measurements Digest","volume":"124 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122418160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Corrections to hyperfine splitting and Lamb shift induced by diagrams with second order radiative insertions in the electron line 电子线中有二阶辐射插入的图引起的超精细分裂和兰姆位移的修正
Proceedings of Conference on Precision Electromagnetic Measurements Digest Pub Date : 1994-12-31 DOI: 10.1109/CPEM.1994.333250
M. I. Eides, S. Karshenboim, V. Shelyuto
{"title":"Corrections to hyperfine splitting and Lamb shift induced by diagrams with second order radiative insertions in the electron line","authors":"M. I. Eides, S. Karshenboim, V. Shelyuto","doi":"10.1109/CPEM.1994.333250","DOIUrl":"https://doi.org/10.1109/CPEM.1994.333250","url":null,"abstract":"Contributions to HFS and to the Lamb shift intervals of order /spl alpha//sup 2/(Z/spl alpha/)/sup 5/ induced by a gauge invariant set of nineteen topologically different graphs with two radiative photons inserted in the electron line are considered. Corrections both to HFS and Lamb shift induced by nine diagrams are calculated in the Fried-Yennie gauge.<<ETX>>","PeriodicalId":388647,"journal":{"name":"Proceedings of Conference on Precision Electromagnetic Measurements Digest","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1994-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123404435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
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