TECH R I.C. NAT’L INST. OF STAND & A111Q5 M05fi31 NBSIR 80-2165 Technical Activities 1980 Center for Absolute Physical Quantities Karl G. Kessler, Director Center for Absolute Physical Quantities National Measurements Laboratory National Bureau of Standards U.S. Department of Commerce Washington, DC 20234 October 1 980 .U56 80-2165 1080 r: c 1 2 National Bureau of Standards Department of Commerce Washington, DC 20234 - -C ^ RATIONAL BUREAU or STANDARDS LIBRARY SEP 1 6 1981 80-2165 NBSIR mol Clcc - Cl. #* * Qtioo TECHNICAL ACTIVITIES 1980 CENTER FOR ABSOLUTE PHYSICAL 7'/*' QUANTITIES vU " Karl G. Kessler, Director Center for Absolute Physical Quantities National Measurements Laboratory National Bureau of Standards U.S. Department of Commerce Washington, DC 20234 October 1 980 Prepared for: National Bureau of Standards Department of Commerce Washington, DC 20234 U.S. DEPARTMENT OF COMMERCE, Philip M. Klutznick, Secretary Luther H. Hodges, Jr., Deputy Secretary Jordan J. Baruch, Assistant Secretary for Productivity, Technology, and Innovation NATIONAL BUREAU OF STANDARDS, Ernest Ambler. Director " UHr.r ’ f"P.' 3; S38 ABSTRACT This report summarizes research projects, measurement method develop- ment, calibration and data evaluation activities carried during Fiscal Year 1980 in the NBS Center for Absolute Physical Quantities. These activities fall in the areas of: quantum metrology; measurements and standards for the electrical units, temperature and pressure, length and mass, time and frequency; and quantum physics. Key words: Electrical measurements and standards; length and mass measurements and standards; temperature and pressure measurements and standards; time and frequency; quantum metrology; quantum physics. i INTRODUCTION This book is Part II of the 1980 Annual Report of the Center for Absolute Physical Quantities and contains a summary of the technical activities of the Center for the period October 1, 1979 to September 30, 1980. The Center is one of the five resources and operating units in the National Measurement Laboratory. The summary of activities is organized in seven sections, one for the technical activities of the Center Office staff, one for the Quantum Metrology Group, and one each for the five divisions of the Center. Each division or group tells its own story in its own way. In general, there is an overview followed by a series of short reports on current projects. Then the publications, invited talks, committee participation and professional interactions during the year are listed. An organization chart of the Center is included at the end of the text. More information about particular work may be desired. To obtain this, the reader should address the individual scientists or their division, c/o Center for Absolute Physical Quantities, B160 Physics Building, National Bureau of Standards, Washington, D.C. 20234. i i . TABLE OF CONTENTS Page ABSTRACT i INTRODUCTION ii SUMMARY OF TECHNICAL ACTIVITIES Center Office 1 Quantum Metrology Group 5 Electrical Measurements and Standards Division 27 Temperature and Pressure Measurements and Standards Division . 72 Length and Mass Measurements and Standards Division 113 Time and Frequency Division 122 Quantum Physics Division 150 CENTER ORGANIZATIONAL CHART 229 . • CENTER OFFICE SUMMARY OF ACTIVITIES FISCAL YEAR 1980 The Center Office includes several scientists who, in addition to their administrative support function also engage in a variety of tech- nical activities. Technical activities of the Deputy Center Director, Dr. Ralph P. Hudson, include research, technical writing and international committee activities related to low temperature physics and thermometry. During the past year, the properties of CMN (cerous magnesium nitrate) power in the millikelvin region were analyzed to reconcile the thermometric behavior of powdered CMN with that of single crystal CMN. Dr. Hudson continues to serve as Consulting Editor in Low Temperature Physics for the forthcoming new edition of the McGraw-Hi 1 1 Encyclopedia of Science and Technology and has written new entries on Adiabatic Demagnetization, Low Temperature Thermometry, and Low-Temperature Physics. He was invited to write a general review on the measurement of temperature published in a recent issue of Review of Scientific Instruments. Dr. Hudson contributes extensively to the international communication of progress in low temperature thermometry and provides valuable technical assistance to the NBS temperature program. Mr. John W. Cooper provides theoretical assistance within the Center and in other Centers to experimental groups working in the area of atomic physics. He provides suggestions for key experiments to be performed using current resources, assists in the planning and carrying out of such experiments and provides interpretations and supporting calculations. As a part of his duties as assistant to the Center Director, Dr. W.G. Schweitzer provides collaborative support to the Length and Mass Measurements and Standards Division in the area of laser technology, laser spectroscopy and precise laser wavelengths for standards in metrology and spectroscopy. 1 PUBLICATIONS B. E. Cole, J. W. Cooper, D. L. Ederer, G. Mehlman and E. B. Saloman, "Stark Effect on Autoionizing Resonances in the Rare Gases," J. Phys. B. Mole. Phys. LI Atom. J_3 , 75 (1980). V. L. Jacobs, J. Davis, B. F. Roznyai , and John W. Cooper, "Multiple Ionization and X-Ray Emission Accompanying the Cascade Decay of Inner- shell Vacancies in Fe," Phys. Rev. A 21_, 1917 (1980). B. E. Cole, J. W. Cooper, and E. B. Saloman, "Field Induced Autoionization in Rare Gas Absorption Spectra Near the Ionization Threshold, Phys. Rev. Lettrs. 45, 887 (1980). R. P. Hudson, "Adiabatic Demagnetization," McGraw-Hill Encyclopedia of Science and Technology. R. P. Hudson, "Low Temperature Thermometry", McGraw-Hill Encyclopedia of Science and Technology. R. P. Hudson, "The Measurement of Temperature," Rev. Sci. Instrum. 51_, (7), 871 (1980). R. P. Hudson, K. Mitsui and R. L. Rusby, "Third Report of Working Group No. 5, Comite Consultatif de Thermometrie, B.I.P.M. ," 13th Session, Sevres, France, June 17-19, 1980. R. P. Hudson, "Low Temperature Physics," McGraw-Hill Encyclopedia of Science and Technology. OTHER R. P. Hudson and B. W. Mangum, "On the Question of an IPTS below IK," 13th Session, Comite Consultatif de Thermometrie, B.I.P.M., Sevres, France, June 17-19, 1980. R. P. Hudson, "Susceptibilities of CMN Powder and Single Crystal at Very Low Temperature: Are They Consistent?", Poster Session, Cornell Symposium on 3 Liquid and Solid He, Cornell University, Ithaca, N.Y. , July 21-25, 1980. 2 INVITED TALKS R. P. Hudson, "Practical Thermometry at Low Temperatures", chaired session and led discussion. Conference on Low Temperature Thermometry, The Institute of Physics, London, England, October 1, 1979. R. P. Hudson, "Millikelvin Thermometry", conducted round-table session at XVth International Congress on Refrigeration (I.I.R.) in Venice, September 23-29, 1979. 3 COMMITTEE MEMBERSHIPS K. G. Kessler, Chairman, American Physical Society, Committee on Arrange- ments, Washington Meeting. K. G. Kessler, Chairman, Earle Plyler Award Committee, American Physical Society. K. G. Kessler, Board of Directors and Executive Committee, Optical Society of America. K. G. Kessler, Chairman, Optical Society of America, Publications Committee. K. G. Kessler, NBS representative, Consultative Committee for the Definition of the Meter. K. G. Kessler, member, American Institute of Physics Publishing Policy Committee. K. G. Kessler, Representative for the OSA to the AAAS Consortium of Affiliates for International Programs. K. G. Kessler, member. Commission 14, International Astronomical Union. R. P. Hudson, member, Fritz London Memorial Award Committee 1973-81 (Chairman, 1976-8). R. P. Hudson, member. Advisory Committee on Thermometry, International Committee on Weights and Measures. R. P. Hudson, Chairman of Working Group 5, Study of Practical Low Temperature Thermometers below 30K, Advisory Committee on Thermometry, International Committee on Weights and Measures; 1974-80. R. P. Hudson, Chairman of Working Group 4, Extension of IPTS below 14K, Advisory Committee on Thermometry, International Committee on Weights and Measures; 1980-. R. P. Hudson, member, International Institute of Refrigeration, Com- mission Al/2, Cryophysics & Cryoengi neeri ng. R. P. Hudson, member, National Committee for 16th International Confer- ence on Low Temperature Physics (LT16), August 1981. R. P. Hudson, member, General Committee, Joint ISA-AIP-NBS Symposium on Temperature, March 1982; Editor-in-Chief of Proceedings. R. P. Hudson, Consulting Editor in Low Temperature Physics for the McGraw-Hi 1 1 Encyclopedia of Science and Technology and its Yearbooks. J. W. Cooper, member, Atomic & Nuclear Data, Editorial Board. 4 QUANTUM METROLOGY GROUP SUMMARY OF ACTIVITIES FISCAL YEAR 1980 I. Overview The Quantum Metrology Group is a diverse collection of scientists engaged in no less than six experimental and theoretical areas all of which involve precision measurements. Some of the experiments are at the forefront of measurement technology. Because of our diversity and small numbers, we are not a division and are thus attached to the Office of the Director of CAPQ. The fields in which we have active programs include gravity, quantum theory of measurement, atomic theory, laser spectroscopy, X-ray spectroscopy using laboratory and synchrotron radiation sources, precision X- and y-ray standards, and solar and plasma