diff --git a/meetings-en/meeting-1956.yml b/meetings-en/meeting-1956.yml index 02147c4..d45d133 100644 --- a/meetings-en/meeting-1956.yml +++ b/meetings-en/meeting-1956.yml @@ -23,9 +23,39 @@ resolutions: date_effective: 1956-01-01 message: |- that, according to the decisions of the 8th General Assembly of the International Astronomical Union (Rome, 1952), the second of ephemeris time (ET) is the fraction + - (12 960 276 813 / 408 986 496) ´ stem:[10^(-9)] of the tropical year for 1900 January 0 at stem:[12 "h"] ET, + stem:[(12 960 276 813) / (408 986 496) xx 10^(-9)] of the tropical year for 1900 January 0 at stem:[12 "h"] ET, actions: - type: decides date_effective: 1956-01-01 message: "The second is the fraction 1/31 556 925.9747 of the tropical year for 1900 January 0 at 12 hours ephemeris time." +- dates: + - 1956-01-01 + title: Système International d’Unités + identifier: 3 + url: https://www.bipm.org/en/CIPM/db/1956/3/ + approvals: + - type: affirmative + degree: unanimous + message: The Comité International des Poids et Mesures, + considerations: + - type: considering + date_effective: 1956-01-01 + message: the task entrusted to it by Resolution 6 of the 9th Conférence Générale des Poids et Mesures (CGPM) concerning the establishment of a practical system of units of measurement suitable for adoption by all countries adhering to the Metre Convention, + - type: considering + date_effective: 1956-01-01 + message: the documents received from twenty-one countries in reply to the enquiry requested by the 9th CGPM, + - type: considering + date_effective: 1956-01-01 + message: Resolution 6 of the 10th CGPM, fixing the base units of the system to be established, + actions: + - type: recommends + date_effective: 1956-01-01 + message: |- + that the name “Système International d’Unités” be given to the system founded on the base units adopted by the 10th CGPM, viz.: + + [This is followed by the list of the six base units with their symbols, reproduced in Resolution 12 of the 11th CGPM (1960)]. + - type: recommends + date_effective: 1956-01-01 + message: |- + that the units listed in the table below be used, without excluding others which might be added later: + + [This is followed by the table of units reproduced in paragraph 4 of Resolution 12 of the 11th CGPM (1960)]. \ No newline at end of file diff --git a/meetings-en/meeting-1964.yml b/meetings-en/meeting-1964.yml index d3256a2..f64d519 100644 --- a/meetings-en/meeting-1964.yml +++ b/meetings-en/meeting-1964.yml @@ -16,14 +16,14 @@ resolutions: considerations: - type: acknowledging date_effective: 1964-01-01 - message: empowered by cgpm-resolution:en/12/5[Resolution 5] of the 12th Conférence + message: *empowered* by cgpm-resolution:en/12/5[Resolution 5] of the 12th Conférence Générale des Poids et Mesures to name atomic or molecular frequency standards for temporary use for time measurements in physics, actions: - type: decides date_effective: 1964-01-01 - message: that the standard to be employed is the transition between the + message: '*declares* that the standard to be employed is the transition between the hyperfine levels stem:[F = 4], stem:[M = 0] and stem:[F = 3], stem:[M = 0] of the ground state ^2^S~1/2~ of the caesium 133 atom, unperturbed by external fields, and that the frequency of this transition is assigned the value 9 192 631 770 - hertz. + hertz.' \ No newline at end of file diff --git a/meetings-en/meeting-1967.yml b/meetings-en/meeting-1967.yml index fec99e5..b8c7783 100644 --- a/meetings-en/meeting-1967.yml +++ b/meetings-en/meeting-1967.yml @@ -23,6 +23,6 @@ resolutions: actions: - type: decides date_effective: 1967-01-01 - message: 'declares that the rules of Resolution 12 of the 11th CGPM apply to the + message: '*declares* that the rules of Resolution 12 of the 11th CGPM apply to the kilogram in the following manner: the names of decimal multiples and submultiples - of the unit of mass are formed by attaching prefixes to the word "gram".' + of the unit of mass are formed by attaching prefixes to the word "gram".' \ No newline at end of file diff --git a/meetings-en/meeting-1969.yml b/meetings-en/meeting-1969.yml index aea4562..7c3061d 100644 --- a/meetings-en/meeting-1969.yml +++ b/meetings-en/meeting-1969.yml @@ -23,13 +23,13 @@ resolutions: actions: - type: decides date_effective: 1969-01-01 - message: the base units, the supplementary units and the derived units of the Système International d'Unités, which form a coherent set, are denoted by the name "SI units"; + message: '*declares* the base units, the supplementary units and the derived units of the Système International d'Unités, which form a coherent set, are denoted by the name "SI units";' - type: decides date_effective: 1969-01-01 - message: the prefixes adopted by the CGPM for the formation of decimal multiples and submultiples of SI units are called "SI prefixes"; + message: '*declares* the prefixes adopted by the CGPM for the formation of decimal multiples and submultiples of SI units are called "SI prefixes";' - type: recommends date_effective: 1969-01-01 message: |- the use of SI units and of their decimal multiples and submultiples whose names are formed by means of SI prefixes. - Note: The name "supplementary units", appearing in cgpm-resolution:en/11/12[Resolution 12] of the 11th CGPM (and in the present Recommendation) is given to SI units for which the General Conference declines to state whether they are base units or derived units. + Note: The name "supplementary units", appearing in cgpm-resolution:en/11/12[Resolution 12] of the 11th CGPM (and in the present Recommendation) is given to SI units for which the General Conference declines to state whether they are base units or derived units. \ No newline at end of file diff --git a/meetings-en/meeting-1970.yml b/meetings-en/meeting-1970.yml new file mode 100644 index 0000000..e61e0db --- /dev/null +++ b/meetings-en/meeting-1970.yml @@ -0,0 +1,18 @@ +--- +metadata: + title: CCDS, 1970 (_In_ CIPM, 1970) + date: 1970-01-01 + source: BIPM - Pavillon de Breteuil +resolutions: +- dates: + - 1970-01-01 + title: Definition of TAI + identifier: 2 + url: + approvals: + - type: affirmative + degree: unanimous + message: |- + International Atomic Time (TAI) is the time reference coordinate established by the Bureau International de l'Heure on the basis of the readings of atomic clocks operating in various establishments in accordance with the definition of the second, the unit of time of the International System of Units. + + In 1980, the definition of TAI was completed as follows (declaration of the CCDS, _BIPM Com. Cons. Déf. Seconde_, 1980, *9*, S 15 and Metrologia, 1981, *17*, 70): + + TAI is a coordinate time scale defined in a geocentric reference frame with the SI second as realized on the rotating geoid as the scale unit. \ No newline at end of file diff --git a/meetings-en/meeting-1980.yml b/meetings-en/meeting-1980.yml index 12a3622..faad8f2 100644 --- a/meetings-en/meeting-1980.yml +++ b/meetings-en/meeting-1980.yml @@ -40,7 +40,7 @@ resolutions: - type: considering date_effective: 1980-01-01 message: |- - considering also + *considering also* that the interpretation given by the CIPM in 1969 for the class of supplementary units introduced in cgpm-resolution:en/11/12[Resolution 12] of the 11th Conférence Générale des Poids et mesures (CGPM) in 1960 allows the freedom of treating the radian and the steradian as SI base units, - type: considering @@ -51,4 +51,4 @@ resolutions: date_effective: 1980-01-01 message: to interpret the class of supplementary units in the International System as a class of dimensionless derived units for which the CGPM allows the - freedom of using or not using tem in expressions for SI derived units. + freedom of using or not using tem in expressions for SI derived units. \ No newline at end of file diff --git a/meetings-en/meeting-1988.yml b/meetings-en/meeting-1988.yml index 7fb4012..04905cf 100644 --- a/meetings-en/meeting-1988.yml +++ b/meetings-en/meeting-1988.yml @@ -33,8 +33,8 @@ resolutions: 4 parts in stem:[10^(7)], and a reproducibility which is significantly better, - type: considering date_effective: 1988-01-01 - message: is of the opinion that no change in this recommended value of the Josephson - constant will be necessary in the foreseeable future, and + message: '*is of the opinion* that no change in this recommended value of the Josephson + constant will be necessary in the foreseeable future, and' actions: - type: recommends date_effective: 1988-01-01 @@ -120,4 +120,4 @@ resolutions: laboratory reference standard of resistance, laboratories follow the most recent edition of the technical guidelines for reliable measurements of the quantized Hall resistance drawn up by the Comité Consultatif d'Électricité and published - by the Bureau International des Poids et Mesures, and + by the Bureau International des Poids et Mesures, and \ No newline at end of file diff --git a/meetings-en/meeting-1989.yml b/meetings-en/meeting-1989.yml index 9e6f051..1fdcae6 100644 --- a/meetings-en/meeting-1989.yml +++ b/meetings-en/meeting-1989.yml @@ -18,18 +18,29 @@ resolutions: date_effective: 1989-01-01 message: |- acting in accordance with cgpm-resolution:en/18/7[Resolution 7] of the 18th Conférence Générale des Poids et Mesures (1987) has adopted the International Temperature Scale of 1990 ( https://www.bipm.org/en/publications/its-90.html[ITS-90]) to supersede the International Practical Temperature Scale of 1968 (IPTS-68). - - The CIPM *notes* that, by comparison with the IPTS-68, the ITS-90 - - * extends to lower temperatures, down to stem:[0.65 "K"], and hence also supersedes the EPT-76, - * is in substantially better agreement with corresponding thermodynamic temperatures, - * has much improved continuity, precision and reproducibility throughout its range and - * has subranges and alternative definitions in certain ranges which greatly facilitate its use. - - The CIPM also *notes* that, to accompany the text of the ITS-90 there will be two further documents, the _Supplementary Information for the ITS-90_ and _Techniques for Approximating the ITS-90_. These documents will be published by the BIPM and periodically updated. - - The CIPM *recommends* - - * that on 1 January 1990 the ITS-90 come into force and - * that from this same date the IPTS-68 and the EPT-76 be abrogated. - actions: [] + - type: noting + date_effective: 1989-01-01 + message: |- + The CIPM *notes* that, by comparison with the IPTS-68, the ITS-90 + + - type: noting + date_effective: 1989-01-01 + message: extends to lower temperatures, down to stem:[0.65 "K"], and hence also supersedes the EPT-76, + - type: noting + date_effective: 1989-01-01 + message: is in substantially better agreement with corresponding thermodynamic temperatures, + - type: noting + date_effective: 1989-01-01 + message: has much improved continuity, precision and reproducibility throughout its range and + - type: noting + date_effective: 1989-01-01 + message: has subranges and alternative definitions in certain ranges which greatly facilitate its use. + - type: noting + date_effective: 1989-01-01 + message: The CIPM also *notes* that, to accompany the text of the ITS-90 there will be two further documents, the _Supplementary Information for the ITS-90_ and _Techniques for Approximating the ITS-90_. These documents will be published by the BIPM and periodically updated. + actions: + - type: recommends + date_effective: 1989-01-01 + message: that on 1 January 1990 the ITS-90 come into force and + - type: recommends + date_effective: 1989-01-01 + message: that from this same date the IPTS-68 and the EPT-76 be abrogated. \ No newline at end of file diff --git a/meetings-en/meeting-2001.yml b/meetings-en/meeting-2001.yml new file mode 100644 index 0000000..7b2ea00 --- /dev/null +++ b/meetings-en/meeting-2001.yml @@ -0,0 +1,18 @@ +--- +metadata: + title: CIPM, 2001 + date: 2001-01-01 + source: BIPM - Pavillon de Breteuil +resolutions: +- dates: + - 2001-01-01 + title: "SI units" and "units of the SI" + identifier: 1 + url: + approvals: + - type: affirmative + degree: unanimous + message: |- + The CIPM approved in 2001 the following proposal of the CCU regarding "SI units" and "units of the SI": + + "We suggest that "SI units" and "units of the SI" should be regarded as names that include both the base units and the coherent derived units, and also all units obtained by combining these with the recommended multiple and sub-multiple prefixes. + + We suggest that the name "coherent SI units" should be used when it is desired to restrict the meaning to only the base units and the coherent derived units." \ No newline at end of file diff --git a/meetings-en/meeting-2002.yml b/meetings-en/meeting-2002.yml index b5fb152..44540d5 100644 --- a/meetings-en/meeting-2002.yml +++ b/meetings-en/meeting-2002.yml @@ -13,9 +13,70 @@ resolutions: approvals: - type: affirmative degree: unanimous - message: Unanimous - considerations: [] - actions: [] + message: The International Committee for Weights and Measures, + considerations: + - type: recalling + date_effective: 2002-01-01 + message: that in 1983 the 17th General Conference (CGPM) adopted a new definition of the metre; + - type: recalling + date_effective: 2002-01-01 + message: |- + that in the same year the CGPM invited the International Committee (CIPM) + + * to draw up instructions for the practical realization of the metre, + * to choose radiations which can be recommended as standards of wavelength for the interferometric measurement of length and draw up instructions for their use, + * to pursue studies undertaken to improve these standards and in due course to extend or revise these instructions; + - type: recalling + date_effective: 2002-01-01 + message: |- + that in response to this invitation the CIPM adopted Recommendation 1 (CI-1983) (_mise en pratique_ of the definition of the metre) to the effect + + * that the metre should be realized by one of the following methods: + ** by means of the length stem:[l] of the path travelled in vacuum by a plane electromagnetic wave in a time stem:[t]; this length is obtained from the measured time stem:[t], using the relation stem:[l = c_0 * t] and the value of the speed of light in vacuum stem:[c_0 = 299 792 458 "m/s"], + ** by means of the wavelength in vacuum stem:[lambda] of a plane electromagnetic wave of frequency stem:[f]; this wavelength is obtained from the measured frequency stem:[f] using the relation stem:[lambda = c_0 // f] and the value of the speed of light in vacuum stem:[c_0 = 299 792 458 "m/s"], + ** by means of one of the radiations from the list below, whose stated wavelength in vacuum or whose stated frequency can be used with the uncertainty shown, provided that the given specifications and accepted good practice are followed; + * that in all cases any necessary corrections be applied to take account of actual conditions such as diffraction, gravitation or imperfection in the vacuum; + * that in the context of general relativity, the metre is considered a unit of proper length. Its definition, therefore, applies only within a spatial extent sufficiently small that the effects of the non-uniformity of the gravitational field can be ignored (note that, at the surface of the Earth, this effect in the vertical direction is about 1 part in 1016 per metre). In this case, the effects to be taken into account are those of special relativity only. The local methods for the realization of the metre recommended in (b) and (c) provide the proper metre but not necessarily that given in (a). Method (a) should therefore be restricted to lengths l which are sufficiently short for the effects predicted by general relativity to be negligible with respect to the uncertainties of realization. For advice on the interpretation of measurements in which this is not the case, see the report of the Consultative Committee for Time and Frequency (CCTF) Working Group on the Application of General Relativity to Metrology (Application of general relativity to metrology, _Metrologia_, 1997, *34*, 261-290); + - type: recalling + date_effective: 2002-01-01 + message: that the CIPM had already recommended a list of radiations for this purpose; + - type: recalling + date_effective: 2002-01-01 + message: also that in 1992 and in 1997 the CIPM revised the practical realization of the definition of the metre; + - type: considering + date_effective: 2002-01-01 + message: that science and technology continue to demand improved accuracy in the realization of the metre; + - type: considering + date_effective: 2002-01-01 + message: that since 1997 work in national laboratories, in the BIPM and elsewhere has identified new radiations and methods for their realization which lead to lower uncertainties; + - type: considering + date_effective: 2002-01-01 + message: that there is an increasing move towards optical frequencies for time-related activities, and that there continues to be a general widening of the scope of application of the recommended radiations of the mise en pratique to cover not only dimensional metrology and the realization of the metre, but also high-resolution spectroscopy, atomic and molecular physics, fundamental constants and telecommunication; + - type: considering + date_effective: 2002-01-01 + message: that a number of new frequency values with reduced uncertainties for radiations of high-stability cold atom and ion standards already listed in the recommended radiations list are now available, that the frequencies of radiations of several new cold atom and ion species have also recently been measured, and that new improved values with substantially reduced uncertainties for a number of optical frequency standards based on gas cells have been determined, including the wavelength region of interest to optical telecommunications; + - type: considering + date_effective: 2002-01-01 + message: that new femtosecond comb techniques have clear significance for relating the frequency of high-stability optical frequency standards to that of the frequency standard realizing the SI second, that these techniques represent a convenient measurement technique for providing traceability to the International System of Units (SI) and that comb technology also can provide frequency sources as well as a measurement technique; + actions: + - type: recognizes + date_effective: 2002-01-01 + message: comb techniques as timely and appropriate, and recommends further research to fully investigate the capability of the techniques; + - type: welcomes + date_effective: 2002-01-01 + message: validations now being made of comb techniques by comparison with other frequency chain techniques; + - type: urges + date_effective: 2002-01-01 + message: national metrology institutes and other laboratories to pursue the comb technique to the highest level of accuracy achievable and also to seek simplicity so as to encourage widespread application; + - type: recommends + date_effective: 2002-01-01 + message: |- + that the list of recommended radiations given by the CIPM in 1997 (Recommendation 1 (CI-1997)) be replaced by the list of radiations given below*, including + + * updated frequency values for cold Ca atom, H atom and the trapped Sr^+^ ion, + * frequency values for new cold ion species including trapped Hg^\+^ ion, trapped In+ ion and trapped Yb^+^ ion, + * updated frequency values for Rb-stabilized lasers, I~2~-stabilized Nd:YAG and He-Ne lasers, CH~4~-stabilized He-Ne lasers and OsO~4~-stabilized CO~2~ lasers at stem:[10 " "mu"m"], + * frequency values for standards relevant to the optical communications bands, including Rb- and C~2~H~2~-stabilized lasers. - dates: - 2002-01-01 title: Dose equivalent @@ -24,12 +85,12 @@ resolutions: approvals: - type: affirmative degree: unanimous - message: The International Committee for Weights and Mesures + message: The International Committee for Weights and Measures, considerations: - type: considering date_effective: 2002-01-01 message: |- - *considering* that + that * the current definition of the SI unit of dose equivalent (sievert) includes a factor "stem:[N]" (product of any other multiplying factors) stipulated by the International Commission on Radiological Protection (ICRP), and - type: considering @@ -52,4 +113,4 @@ resolutions: The Committee further *decides* to maintain the final sentence in the explanation as follows: - In order to avoid any risk of confusion between the absorbed dose stem:[D] and the dose equivalent stem:[H], the special names for the respective units should be used, that is, the name gray should be used instead of joules per kilogram for the unit of absorbed dose stem:[D] and the name sievert instead of joules per kilogram for the unit of dose equivalent stem:[H]. + In order to avoid any risk of confusion between the absorbed dose stem:[D] and the dose equivalent stem:[H], the special names for the respective units should be used, that is, the name gray should be used instead of joules per kilogram for the unit of absorbed dose stem:[D] and the name sievert instead of joules per kilogram for the unit of dose equivalent stem:[H]. \ No newline at end of file diff --git a/meetings-en/meeting-2003.yml b/meetings-en/meeting-2003.yml index 894f59e..9478408 100644 --- a/meetings-en/meeting-2003.yml +++ b/meetings-en/meeting-2003.yml @@ -16,25 +16,26 @@ resolutions: considerations: - type: considering date_effective: 2003-01-01 - message: that improved frequency values for radiations of some high-stability - cold ion standards already documented in the recommended radiations list have - recently become available; + message: |- + that + + improved frequency values for radiations of some high-stability cold ion standards already documented in the recommended radiations list have recently become available; - type: considering date_effective: 2003-01-01 - message: that improved frequency values for the infra-red gas-cell-based - optical frequency standard in the optical telecommunications region, already - documented in the recommended radiations list, have been determined; + message: improved frequency values for the infra-red gas-cell-based optical frequency standard in the optical telecommunications region, already documented in the recommended radiations list, have been determined; - type: considering date_effective: 2003-01-01 - message: that femtosecond comb-based frequency measurement for certain - iodine gas-cell standards on the subsidiary recommended source list have recently - been made for the first time, leading to signicantly reduced uncertainty; + message: femtosecond comb-based frequency measurements for certain iodine gas-cell standards on the subsidiary recommended source list have recently been made for the first time, leading to significantly reduced uncertainty; actions: - - type: encourages + - type: proposes date_effective: 2003-01-01 message: |- - *proposes* that the _recommended radiation_ list be revised to include the following: - - * updated frequency values for the single trapped ^88^Sr^\+^ ion quadrupole transition and the single trapped ^171^Yb^+^ octupole transition; - * an updated frequency value for the stem:["C"_(2)"H"_(2)]-stabilized standard at stem:[1.54 " "mu"m"]; - * updated frequency values for the I~2~-stabilized standards at stem:[543 " nm"] and stem:[515 " "nm]. + that the _recommended radiation_ list be revised to include the following: + + updated frequency values for the single trapped ^88^Sr^\+^ ion quadrupole transition and the single trapped ^171^Yb^+^ octupole transition; + - type: proposes + date_effective: 2003-01-01 + message: an updated frequency value for the C~2~H~2~-stabilized standard at stem:[1.54 " "mu"m"]; + - type: proposes + date_effective: 2003-01-01 + message: updated frequency values for the I~2~-stabilized standards at 543 nm and 515 nm. \ No newline at end of file diff --git a/meetings-en/meeting-2005.yml b/meetings-en/meeting-2005.yml index 7eed5bd..202a846 100644 --- a/meetings-en/meeting-2005.yml +++ b/meetings-en/meeting-2005.yml @@ -12,9 +12,37 @@ resolutions: approvals: - type: affirmative degree: unanimous - message: Unanimous - considerations: [] - actions: [] + message: The International Committee for Weights and Measures (CIPM), + considerations: + - type: considering + date_effective: 2005-01-01 + message: that the kelvin, unit of thermodynamic temperature, is defined as the fraction 1/273.16 of the thermodynamic temperature of the triple point of water, + - type: considering + date_effective: 2005-01-01 + message: that the temperature of the triple point depends on the relative amount of isotopes of hydrogen and oxygen present in the sample of water used, + - type: considering + date_effective: 2005-01-01 + message: that this effect is now one of the major sources of the observed variability between different realizations of the water triple point, + actions: + - type: decides + date_effective: 2005-01-01 + message: that the definition of the kelvin refer to water of a specified isotopic composition, + - type: decides + date_effective: 2005-01-01 + message: |- + that this composition be: + + 0.000 155 76 mole of ^2^H per mole of ^1^H, + + 0.000 379 9 mole of ^17^O per mole of ^16^O, and + + 0.002 005 2 mole of ^18^O per mole of ^16^O, + + which is the composition of the International Atomic Energy Agency reference material Vienna Standard Mean Ocean Water (VSMOW), as recommended by IUPAC in "Atomic Weights of the Elements: Review 2000". + - type: decides + date_effective: 2005-01-01 + message: |- + that this composition be stated in a note attached to the definition of the kelvin in the SI brochure as follows: + + "This definition refers to water having the isotopic composition defined exactly by the following amount of substance ratios: 0.000 155 76 mole of 2H per mole of 1H, 0.000 379 9 mole of 17O per mole of 16O and 0.002 005 2 mole of 18O per mole of 16O". - dates: - 2005-01-01 title: Revision of the Mise en pratique list of recommended radiations @@ -23,6 +51,45 @@ resolutions: approvals: - type: affirmative degree: unanimous - message: Unanimous - considerations: [] - actions: [] + message: The International Committee for Weights and Measures (CIPM), + considerations: + - type: considering + date_effective: 2005-01-01 + message: |- + that + + improved frequency values for radiations of some high-stability cold ion and cold atom standards already documented in the recommended radiations list have recently become available; + - type: considering + date_effective: 2005-01-01 + message: improved frequency values for the infra-red gas-cell-based optical frequency standard in the optical telecommunications region, already documented in the recommended radiations list, have been determined; + - type: considering + date_effective: 2005-01-01 + message: improved frequency values for certain iodine gas-cell standard, already documented in the subsidiary recommended source list, have been determined; + - type: considering + date_effective: 2005-01-01 + message: frequencies of new cold atoms, of atoms in the near-infrared region and of molecules in the optical telecommunications region have been determined by femtosecond comb-based frequency measurements for the first time; + actions: + - type: decides + date_effective: 2005-01-01 + message: |- + that the list of _recommended radiations_ be revised to include the following: + + updated frequency values for the single trapped ^88^Sr^\+^ ion quadrupole transition, the single trapped ^199^Hg^+^ quadrupole transition and the single trapped ^171^Yb^+^ quadrupole transition; + - type: decides + date_effective: 2005-01-01 + message: an updated frequency value for the Ca atom transition; + - type: decides + date_effective: 2005-01-01 + message: an updated frequency value for the C~2~H~2~-stabilized standard at stem:[1.54 " "mu"m"]; + - type: decides + date_effective: 2005-01-01 + message: an updated frequency value for the I~2~-stabilized standard at 515 nm; + - type: decides + date_effective: 2005-01-01 + message: the addition of the ^87^Sr atom transition at 698 nm; + - type: decides + date_effective: 2005-01-01 + message: the addition of the ^87^Rb atom two-photon transitions at 760 nm; + - type: decides + date_effective: 2005-01-01 + message: the addition of the ^12^C~2~H~2~ (stem:[nu_1 + nu_3]) band and the ^13^C~2~H~2~ (stem:[nu_1 + nu_3]) and (stem:[nu_1 + nu_3 + nu_4 + nu_5]) bands at stem:[1.54 " "mu"m"]. \ No newline at end of file diff --git a/meetings-en/meeting-2006.yml b/meetings-en/meeting-2006.yml new file mode 100644 index 0000000..1d819d4 --- /dev/null +++ b/meetings-en/meeting-2006.yml @@ -0,0 +1,41 @@ +--- +metadata: + title: CIPM, 2006 + date: 2006-01-01 + source: BIPM - Pavillon de Breteuil +resolutions: +- dates: + - 2006-01-01 + title: Concerning secondary representations of the second + identifier: 1 + url: https://www.bipm.org/en/CIPM/db/2006/1/ + approvals: + - type: affirmative + degree: unanimous + message: The International Committee for Weights and Measures (CIPM), + considerations: + - type: considering + date_effective: 2006-01-01 + message: |- + that + + a common list of "Recommended values of standard frequencies for applications including the practical realization of the metre and secondary representations of the second" shall be established, + - type: considering + date_effective: 2006-01-01 + message: the CCL/CCTF Joint Working Group (JWG) on the _Mise en Pratique_ of the Definition of the Metre and the Secondary Representations of the Second in its meeting at the International Bureau of Weights and Measures (BIPM) in September 2005 discussed possible candidates to be included in this list for secondary representations of the second, + - type: considering + date_effective: 2006-01-01 + message: the CCL/CCTF JWG reviewed and updated the values for the Hg ion, Sr ion, Yb ion, and the Sr neutral atom transition frequencies in its session in September 2006, + - type: considering + date_effective: 2006-01-01 + message: the CCTF in its Recommendation CCTF 1 (2004) already recommended the unperturbed ground-state hyperfine quantum transition frequency of 87Rb as a secondary representation of the second; + actions: + - type: recommends + date_effective: 2006-01-01 + message: |- + that the following transition frequencies shall be used as secondary representations of the second and be included into the new list of "Recommended values of standard frequencies for applications including the practical realization of the metre and secondary representations of the second" + * the unperturbed ground-state hyperfine quantum transition of ^87^Rb with a frequency of stem:[f^(87)_(Rb) = 6 834 682 610.904 324 " Hz"] and an estimated relative standard uncertainty of stem:[3 xx 10^(−15)], + * the unperturbed optical 5s ^2^S~1/2~ – 4d ^2^D~5/2~ transition of the ^88^Sr^+^ ion with a frequency of stem:[f^(88)Sr^+ = 444 779 044 095 484 " Hz"] and a relative uncertainty of stem:[7 xx 10^(−15)], + * the unperturbed optical 5d^10^ 6s ^2^S~1/2~ (_F_ = 0) – 5d^9^ 6s^2^ ^2^D~5/2~ (_F_ = 2) transition of the ^199^Hg^\+^ ion with a frequency of stem:[f^(199)Hg^+ = 1 064 721 609 899 145 " Hz"] and a relative standard uncertainty of stem:[3 xx 10^(−15)], + * the unperturbed optical 6s ^2^S~1/2~ (_F_ = 0) – 5d ^2^D~3/2~ (_F_ = 2) transition of the ^171^Yb^\+^ ion with a frequency of stem:[f^(171)Yb^+ = 688 358 979 309 308 " Hz"] and a relative standard uncertainty of stem:[9 xx 10^(−15)], + * the unperturbed optical transition 5s^2^ ^1^S_0 – 5s 5p ^3^P~0~ of the ^87^Sr neutral atom with a frequency of stem:[f^(87)_(Sr) = 429 228 004 229 877 " Hz"] and a relative standard uncertainty of stem:[1.5 xx 10^(−14)]. \ No newline at end of file diff --git a/meetings-en/meeting-2007.yml b/meetings-en/meeting-2007.yml new file mode 100644 index 0000000..0aab002 --- /dev/null +++ b/meetings-en/meeting-2007.yml @@ -0,0 +1,41 @@ +--- +metadata: + title: CIPM, 2007 + date: 2007-01-01 + source: BIPM - Pavillon de Breteuil +resolutions: +- dates: + - 2007-01-01 + title: Revision of the Mise en pratique list of recommended radiations + identifier: 1 + url: https://www.bipm.org/en/CIPM/db/2007/1/ + approvals: + - type: affirmative + degree: unanimous + message: The International Committee for Weights and Measures, + considerations: + - type: considering + date_effective: 2007-01-01 + message: |- + that + + improved frequency values of molecules in the optical telecommunications region, already documented in the list of standard frequencies, have been determined by femtosecond comb-based frequency measurements; + - type: considering + date_effective: 2007-01-01 + message: frequencies of molecules in the optical telecommunications region have been determined by femtosecond comb-based frequency measurements for the first time; + - type: considering + date_effective: 2007-01-01 + message: frequencies of certain iodine gas-cell absorptions close to the 532 nm optical frequency standard have been determined by femtosecond comb-based frequency measurements for the first time; + actions: + - type: proposes + date_effective: 2007-01-01 + message: |- + that the list of standard frequencies be revised to include the following: + + an updated list of frequency values for the ^12^C~2~H~2~ (stem:[nu_1 + nu_3]) band at stem:[1.54 " "mu"m"]; + - type: proposes + date_effective: 2007-01-01 + message: the addition of frequency values for the ^12^C~2~HD (stem:[2nu_1]) band at stem:[1.54 " "mu"m"]; + - type: proposes + date_effective: 2007-01-01 + message: the addition of frequency values for the hyperfine components of the P(142) 37-0, R(121) 35-0 and R(85) 33-0 iodine transitions at 532 nm. \ No newline at end of file diff --git a/meetings-en/meeting-2009.yml b/meetings-en/meeting-2009.yml new file mode 100644 index 0000000..1f0847c --- /dev/null +++ b/meetings-en/meeting-2009.yml @@ -0,0 +1,44 @@ +--- +metadata: + title: CIPM, 2009 + date: 2009-01-01 + source: BIPM - Pavillon de Breteuil +resolutions: +- dates: + - 2009-01-01 + title: Updates to the list of standard frequencies + identifier: 2 + url: https://www.bipm.org/en/CIPM/db/2009/2/ + approvals: + - type: affirmative + degree: unanimous + message: The International Committee for Weights and Measures (CIPM), + considerations: + - type: considering + date_effective: 2009-01-01 + message: |- + that + + a common list of “Recommended values of standard frequencies for applications including the practical realization of the metre and secondary representations of the second” has been established; + - type: considering + date_effective: 2009-01-01 + message: the CCL-CCTF Frequency Standards Working Group (FSWG) has reviewed several promising candidates for inclusion in the list; + actions: + - type: recommends + date_effective: 2009-01-01 + message: |- + that the following transition frequencies shall be included or updated in the list of recommended standard frequencies: + + the unperturbed optical transition 5s^2^ ^1^S~0~ – 5s 5p ^3^P~0~ of the ^87^Sr neutral atom with a frequency of f = 429 228 004 229 873.7 Hz and a relative standard uncertainty of stem:[1 xx 10^(−15)] (this radiation is already endorsed by the CIPM as a secondary representation of the second); + - type: recommends + date_effective: 2009-01-01 + message: the unperturbed optical transition 5s^2^ ^1^S~0~ – 5s 5p ^3^P~0~ of the ^88^Sr neutral atom with a frequency of f = 429 228 066 418 012 Hz and a relative standard uncertainty of stem:[1 xx 10^(−14)]; + - type: recommends + date_effective: 2009-01-01 + message: the unperturbed optical transition 4s ^2^S~1/2~ – 3d ^2^D~5/2~ of the ^40^Ca^+^ ion with a frequency of f = 411 042 129 776 393 Hz and a relative standard uncertainty of stem:[4 xx 10^(−14)]; + - type: recommends + date_effective: 2009-01-01 + message: the unperturbed optical transition ^2^S~1/2~ (_F_ = 0) – ^2^F~7/2~ (_F_ = 3, _m_~F~ = 0) of the ^171^Yb^+^ ion with a frequency of f = 642 121 496 772 657 Hz and a relative standard uncertainty of stem:[6 xx 10^(−14)]; + - type: recommends + date_effective: 2009-01-01 + message: the unperturbed optical transition 6s^2^ ^1^S~0~ (_F_ = 1/2) – 6s 6p ^3^P~0~ (_F_ = 1/2) of the ^171^Yb neutral atom with a frequency of f = 518 295 836 590 864 Hz and a relative standard uncertainty of stem:[1.6 xx 10^(−13)]. \ No newline at end of file diff --git a/meetings-en/meeting-2013.yml b/meetings-en/meeting-2013.yml new file mode 100644 index 0000000..80fd424 --- /dev/null +++ b/meetings-en/meeting-2013.yml @@ -0,0 +1,73 @@ +--- +metadata: + title: CIPM, 2013 + date: 2013-01-01 + source: BIPM - Pavillon de Breteuil +resolutions: +- dates: + - 2013-01-01 + title: Updates to the list of standard frequencies + identifier: 1 + url: + approvals: + - type: affirmative + degree: unanimous + message: The International Committee for Weights and Measures (CIPM), + considerations: + - type: considering + date_effective: 2013-01-01 + message: |- + that + + a common list of "Recommended values of standard frequencies for applications including the practical realization of the metre and secondary representations of the second" has been established, + - type: considering + date_effective: 2013-01-01 + message: the CCL-CCTF Frequency Standards Working Group (FSWG) has reviewed several candidates for inclusion into the list, + actions: + - type: recommends + date_effective: 2013-01-01 + message: |- + the following changes to the list of "Recommended values of standard frequencies for applications including the practical realization of the metre and secondary representations of the second": + + that the following transition frequency be added to the list: + + * the unperturbed optical transition 6s^2^ ^1^S~0~ – 6s 6p ^3^P~0~ of the ^199^Hg neutral atom with a frequency of 1 128 575 290 808 162 Hz and an estimated relative standard uncertainty of stem:[1.7 xx 10^(−14)]; + - type: recommends + date_effective: 2013-01-01 + message: |- + that the following transition frequencies be updated in the list: + + * the unperturbed optical transition 4s ^2^S~1/2~ – 3d ^2^D~5/2~ of the ^40^Ca^+^ ion with a frequency of 411 042 129 776 395 Hz and an estimated relative standard uncertainty of stem:[1.5 xx 10^(−14)]; + * the unperturbed optical transition 1S – 2S of the ^1^H neutral atom with a frequency of 1 233 030 706 593 518 Hz and an estimated relative standard uncertainty of stem:[1.2 xx 10^(−14)]; + + Note: This frequency corresponds to half of the energy difference between the 1S and 2S states; + - type: recommends + date_effective: 2013-01-01 + message: |- + that the following transition frequencies be updated in the list and endorsed as secondary representations of the second: + + * the unperturbed optical transition 6s ^2^S~1/2~ – 4f ^13^6s~2~ ^2^F~7/2~ of the ^171^Yb^+^ ion (octupole) with a frequency of 642 121 496 772 645.6 Hz and an estimated relative standard uncertainty of stem:[1.3 xx 10^(−15)]; + * the unperturbed optical transition 6s^2^ ^1^S~0~ – 6s 6p ^3^P0 of the ^171^Yb neutral atom with a frequency of 518 295 836 590 865.0 Hz and an estimated relative standard uncertainty of stem:[2.7 xx 10^(−15)]; + - type: recommends + date_effective: 2013-01-01 + message: |- + that the following transition frequency be added to the list and as a secondary representation of the second: + + * the unperturbed optical transition 3s^2^ ^1^S~0~ – 3s 3p ^3^P~0~ of the ^27^Al^+^ ion with a frequency of 1 121 015 393 207 857.3 Hz and an estimated relative standard uncertainty of stem:[1.9 xx 10^(−15)]; + - type: recommends + date_effective: 2013-01-01 + message: |- + that the following transition frequencies be updated in the list and as secondary representations of the second: + + * the unperturbed optical transition 5d ^10^6s ^2^S~1/2~ – 5d ^9^6s^2^ ^2^D~5/2~ of the ^199^Hg^+^ ion with a frequency of 1 064 721 609 899 145.3 Hz and an estimated relative standard uncertainty of stem:[1.9 xx 10^(−15)]; + * the unperturbed optical transition 6s ^2^S~1/2~ (_F_ = 0, _m_~F~ = 0) – 5d ^2^D~3/2~ (_F_ = 2, _m_~F~ = 0) of the ^171^Yb^+^ ion (quadrupole) with a frequency of 688 358 979 309 307.1 Hz and an estimated relative standard uncertainty of stem:[3 xx 10^(−15)]; + * the unperturbed optical transition 5s ^2^S~1/2~ – 4d ^2^D~5/2~ of the ^88^Sr^+^ ion with a frequency of 444 779 044 095 485.3 Hz and an estimated relative standard uncertainty of stem:[4.0 xx 10^(−15)]; + * the unperturbed optical transition 5s^2^ ^1^S~0~ – 5s5p ^3^P~0~ of the ^87^Sr neutral atom with a frequency of 429 228 004 229 873.4 Hz and an estimated relative standard uncertainty of stem:[1 xx 10^(−15)]; + - type: recommends + date_effective: 2013-01-01 + message: |- + that the following transition frequency be updated as a secondary representation of the second: + + * the unperturbed ground - state hyperfine transition of ^87^Rb with a frequency of 6 834 682 610.904 312 Hz and an estimated relative standard uncertainty of stem:[1.3 xx 10^(−15)]. + + Note: The value of the estimated standard uncertainty is assumed to correspond to a confidence level of 68 %. However, given the very limited number of available data there is a possibility that in hindsight this might not prove to be exact. \ No newline at end of file diff --git a/meetings-en/meeting-2015.yml b/meetings-en/meeting-2015.yml new file mode 100644 index 0000000..829118e --- /dev/null +++ b/meetings-en/meeting-2015.yml @@ -0,0 +1,77 @@ +--- +metadata: + title: CIPM, 2015 + date: 2015-01-01 + source: BIPM - Pavillon de Breteuil +resolutions: +- dates: + - 2015-01-01 + title: Updates to the list of standard frequencies + identifier: 2 + url: + approvals: + - type: affirmative + degree: unanimous + message: The International Committee for Weights and Measures (CIPM), + considerations: + - type: considering + date_effective: 2015-01-01 + message: a common list of “Recommended values of standard frequencies for applications including the practical realization of the metre and secondary representations of the second” has been established, + - type: considering + date_effective: 2015-01-01 + message: the CCL-CCTF Frequency Standards Working Group (WGFS) has reviewed several candidates for updating the list, + actions: + - type: recommends + date_effective: 2015-01-01 + message: |- + that the following transition frequencies shall be updated in the list of recommended values of standard frequencies: + + the unperturbed optical transition 6s^2^ ^1^S~0~ – 6s6p ^3^P~0~ of the ^199^Hg neutral atom with a frequency of f~199Hg~ = 1 128 575 290 808 154.8 Hz and an estimated relative standard uncertainty of stem:[6 xx 10^(−16)]; + - type: recommends + date_effective: 2015-01-01 + message: the unperturbed optical transition 6s ^2^S~1/2~ – 4f^13^ 6s^2^ ^2^F~7/2~ of the ^171^Yb^\+^ ion with a frequency of f~171Yb+~ (octupole) = 642 121 496 772 645.0 Hz and an estimated relative standard uncertainty of stem:[6 xx 10^(−16)] (this radiation is already endorsed by the CIPM as a secondary representation of the second); + - type: recommends + date_effective: 2015-01-01 + message: the unperturbed optical transition 6s ^2^S~1/2~ (_F_ = 0, _m_~F~ = 0) – 5d ^2^D~3/2~ (_F_ = 2, _m_~F~ = 0) of the ^171^Yb^+^ ion with a frequency of f~171Yb+~ (quadrupole) = 688 358 979 309 308.3 Hz and an estimated relative standard uncertainty of stem:[6 xx 10^(−16)] (this radiation is already endorsed by the CIPM as a secondary representation of the second); + - type: recommends + date_effective: 2015-01-01 + message: the unperturbed optical transition 5s ^2^S~1/2~ – 4d ^2^D~5/2~ of the ^88^Sr^+^ ion with a frequency of f~88Sr+~ = 444 779 044 095 486.6 Hz and an estimated relative standard uncertainty of stem:[1.6 xx 10^(−15)] (this radiation is already endorsed by the CIPM as a secondary representation of the second); + - type: recommends + date_effective: 2015-01-01 + message: the unperturbed optical transition 4s ^2^S~1/2~ – 3d ^2^D~5/2~ of the ^40^Ca^+^ ion with a frequency of f~40Ca+~ = 411 042 129 776 398.4 Hz and an estimated relative standard uncertainty of stem:[1.2 xx 10^(−14)]; + - type: recommends + date_effective: 2015-01-01 + message: the unperturbed optical transition 1S – 2S of the ^1^H neutral atom with a frequency of f~1H~ = 1 233 030 706 593 514 Hz and an estimated relative standard uncertainty of stem:[9 xx 10^(−15)]. + + Note: This frequency corresponds to half of the energy difference between the 1S and 2S states; + - type: recommends + date_effective: 2015-01-01 + message: the unperturbed optical transition 5s^2^ ^1^S~0~ – 5s5p ^3^P~0~ of the ^87^Sr neutral atom with a frequency of f~87Sr~ = 429 228 004 229 873.2 Hz and an estimated relative standard uncertainty of stem:[5 xx 10^(−16)] (this radiation is already endorsed by the CIPM as a secondary representation of the second); + - type: recommends + date_effective: 2015-01-01 + message: the unperturbed optical transition 6s^2^ ^1^S~0~ – 6s6p ^3^P~0~ of the ^171^Yb neutral atom with a frequency of f~171Yb~ = 518 295 836 590 864.0 Hz and an estimated relative standard uncertainty of stem:[2 xx 10^(−15)] (this radiation is already endorsed by the CIPM as a secondary representation of the second); + - type: recommends + date_effective: 2015-01-01 + message: the unperturbed ground-state hyperfine transition of ^87^Rb with a frequency of f~87Rb~ = 6 834 682 610.904 310 Hz and an estimated relative standard uncertainty of stem:[7 xx 10^(−16)] (this radiation is already endorsed by the CIPM as a secondary representation of the second). + - type: recommends + date_effective: 2015-01-01 + message: |- + and also *recommends* + + that the following transition frequencies shall be included in the list of recommended values of standard frequencies: + + * Absorbing molecule ^127^I~2~, saturated absorption a~1~ component, R(36) 32-0 transition. + + The values:: stem:[f_(a1) = 564 074 632.42 " MHz"] + + stem:[lambda_(a1) = 531 476 582.65 " fm"] + + with an estimated relative standard uncertainty of stem:[1 xx 10^(−10)] apply to the radiation of a frequency-doubled diode DFB laser, stabilized with an iodine cell external to the laser. + + * Absorbing atom ^87^Rb 5S~1/2~ - 5P~3/2~ crossover between the d and f hyperfine components of the saturated absorption at 780 nm (D2 transition) + + The values:: stem:[f_("d/f crossover") = 384 227 981.9 " MHz"] + + stem:[lambda_("d/f crossover") = 780 246 291.6 " fm"] + + with an estimated relative standard uncertainty of stem:[5 xx 10^(−10)] apply to the radiation of a tunable External Cavity Diode Laser, stabilized to the d/f crossover in a rubidium cell external to the laser. + + Note: The value of the standard uncertainty is assumed to correspond to a confidence level of 68 %. However, given the limited availability of data there is a possibility that in hindsight this might not prove to be exact \ No newline at end of file