CIRCULAR T 197 ISSN 1143-1393 2004 JUNE 16, 08h UTC BUREAU INTERNATIONAL DES POIDS ET MESURES ORGANISATION INTERGOUVERNEMENTALE DE LA CONVENTION DU METRE PAVILLON DE BRETEUIL F-92312 SEVRES CEDEX TEL. +33 1 45 07 70 70 FAX. +33 1 45 34 20 21 tai@bipm.org 1 - Coordinated Universal Time UTC and its local realizations UTC(k). Computed values of [UTC-UTC(k)]. From 1999 January 1, 0h UTC, TAI-UTC = 32 s. Date 2004 0h UTC APR 29 MAY 4 MAY 9 MAY 14 MAY 19 MAY 24 MAY 29 MJD 53124 53129 53134 53139 53144 53149 53154 Laboratory k [UTC-UTC(k)]/ns AOS (Borowiec) -84.1 -90.4 -94.1 -97.2 -97.3 -96.8 -94.5 APL (Laurel) -0.9 -9.5 -18.5 -11.2 -13.6 -13.6 -12.4 AUS (Sydney) -449.5 -462.7 -463.0 -447.8 -455.9 -467.2 -452.1 BEV (Wien) -6.3 -10.0 -11.5 -9.0 -8.3 -10.6 -13.0 BIRM (Beijing) 1952.6 315.7 333.9 356.1 370.8 389.0 409.4 (1) CAO (Cagliari) -3851.0 -3844.4 -3818.0 -3808.4 -3792.5 -3775.9 -3765.2 CH (Bern) 2.9 -49.7 -52.8 -58.0 -63.4 -55.9 -54.7 (2) CNM (Queretaro) 2.2 4.9 11.2 8.9 10.8 15.8 21.0 CNMP (Panama) -3244.0 -3287.3 -3360.3 -3404.7 -122.9 -174.3 -222.9 (3) CSIR (Pretoria) 1715.8 1643.1 1586.4 1521.9 1448.7 1367.6 1305.1 DLR (Oberpfaffenhofen) 49.7 49.9 51.5 56.4 56.4 62.2 68.6 DTAG (Darmstadt) 222.7 215.4 217.3 217.1 219.7 229.0 234.3 HKO (Hong Kong) 1694.1 1758.4 1828.7 1902.0 1968.0 386.2 449.8 (4) IEN (Torino) 18.2 18.8 18.9 35.8 29.2 30.2 20.8 IFAG (Wettzell) -2910.0 -2916.6 -2926.7 -2923.6 -2937.2 -2950.6 -2960.2 IGMA (Buenos Aires) -97.9 -99.1 -97.3 -98.6 -98.6 -97.7 -99.6 INPL (Jerusalem) -9795.3 -9836.1 -9877.0 -9910.8 -9943.6 -9987.3 -10026.5 JATC (Lintong) -10969.7 -10958.4 -10952.6 -10945.5 -10936.5 -10925.2 -10913.6 JV (Kjeller) -9202.0 -9159.1 -9140.6 -9144.8 -9095.6 -9023.7 -8998.5 KRIS (Daejon) -2.0 -13.5 -16.5 -14.4 -14.3 -14.7 -13.4 LDS (Leeds) 345.2 369.4 390.3 404.1 422.0 447.9 484.2 LT (Vilnius) 163.4 145.9 130.9 151.0 149.9 154.9 157.7 MSL (Lower Hutt) 45.2 63.2 66.9 62.0 73.3 80.1 92.0 NAO (Mizusawa) -165.6 -178.8 -176.1 -174.8 -180.6 -187.1 -190.8 NICT (Tokyo) 15.7 21.7 18.3 23.6 23.7 27.1 28.9 NIM (Beijing) -2665.3 -2667.0 -2657.0 -2655.1 -2661.7 -2662.1 -2666.0 NIMB (Bucharest) -312.9 -342.1 -340.9 -355.7 -341.2 -364.1 -362.8 NIMT (Bangkok) -1154.9 -1169.1 -1183.1 -1204.5 -1220.9 -1240.7 -1265.5 NIS (Cairo) - - 10.2 14.8 37.3 59.1 88.8 (5) NIST (Boulder) 10.3 10.5 10.6 9.9 8.9 5.4 2.8 NMC (Sofiya) -3858.5 -3872.4 -3895.8 -3930.8 -3971.6 -3988.9 -4004.9 NMIJ (Tsukuba) 144.3 151.6 150.1 151.8 155.0 163.2 158.5 NMLS (Shah Alam) - - - - - - - NPL (Teddington) 53.2 53.1 55.6 55.7 63.8 64.4 58.5 NPLI (New-Delhi) 7255.8 7287.7 7320.5 7378.7 7424.4 7472.7 7517.6 NRC (Ottawa) 32.7 34.8 31.1 21.8 16.4 24.9 24.3 NTSC (Lintong) -37.7 -29.0 -32.4 -32.1 -28.2 -29.6 -37.3 OMH (Budapest) 9032.0 9031.4 9061.8 9065.3 9060.4 9071.3 9090.7 ONBA (Buenos Aires) -370.2 -387.6 -343.0 -389.1 -431.4 -406.1 -345.6 ONRJ (Rio de Janeiro) 3200.4 2962.1 2719.4 2478.3 2244.6 1997.4 1750.7 OP (Paris) 17.4 19.2 21.1 25.8 17.9 17.0 18.1 ORB (Bruxelles) -28.6 -26.4 -24.4 -21.4 -22.6 -24.5 -25.3 PL (Warszawa) -120.9 -118.2 -116.4 -111.0 -113.2 -103.9 -95.3 PTB (Braunschweig) -34.2 -33.0 -31.5 -26.1 -24.2 -21.1 -24.0 ROA (San Fernando) -12.2 -23.2 -28.9 -30.9 -38.5 -39.7 -34.7 SCL (Hong Kong) 3.0 7.9 17.7 22.2 14.4 3.0 1.4 SG (Singapore) 49.7 31.2 9.4 -11.7 -17.8 -23.8 -17.5 SMU (Bratislava) -9875.9 -9899.5 -9932.2 -9968.0 -9997.8 -10043.2 -10060.3 SP (Boras) 298.8 311.7 324.8 330.8 341.7 343.3 353.6 SU (Moskva) -12.8 -5.1 -4.0 0.0 0.8 -2.3 -4.0 TCC (Concepcion) -6981.4 -7022.2 -7054.3 -7117.2 -7164.8 -7204.1 -7270.0 TL (Chung-Li) 28.0 23.0 12.4 16.8 18.3 23.3 22.8 TP (Praha) 33.4 28.4 27.9 23.9 18.1 8.7 12.1 UME (Gebze-Kocaeli) 213.9 225.5 241.2 246.5 257.5 253.4 239.9 USNO (Washington DC) -5.2 -4.9 -4.3 -3.7 -3.9 -3.3 -2.9 VSL (Delft) 20.3 25.3 20.1 17.7 15.9 7.9 3.1 - Notes on section 1: (1) BIRM: Apparent time step of [UTC-UTC(BIRM)] of about -1660 ns between MJD 53124 and 53129. (2) CH : Time step of UTC(CH) of +50 ns on MJD = 53129. (3) CNMP: Apparent time step of [UTC-UTC(CNMP)] of about +3280 ns between MJD 53139 and 53144. (4) HKO : Apparent time step of [UTC-UTC(HKO)] of about -1640 ns between MJD 53144 and 53149. (5) NIS : National Institute for Standards, Cairo (Egypt). 2 - International Atomic Time TAI and Local atomic time scales TA(k). Computed values of [TAI-TA(k)]. Date 2004 0h UTC APR 29 MAY 4 MAY 9 MAY 14 MAY 19 MAY 24 MAY 29 MJD 53124 53129 53134 53139 53144 53149 53154 Laboratory k [TAI-TA(k)]/ns CH (Bern) 42963.5 43087.7 43211.3 43332.9 43452.4 43577.6 43696.6 F (Paris) 169311.8 169309.1 169304.2 169298.9 169293.1 169286.6 169284.1 IEN (Torino) 35655.3 35768.0 35894.5 36015.4 36132.6 36248.5 36362.3 JATC (Lintong) -34787.7 -34812.4 -34841.6 -34871.5 -34907.5 -34938.2 -34968.6 KRIS (Taejon) 7117.2 7128.5 7148.2 7172.9 7195.5 7217.6 7241.4 NICT (Tokyo) 186906.1 187105.4 187306.7 187516.5 187720.9 187927.3 188130.2 NIST (Boulder) -45263425.8 -45263621.9 -45263818.0 -45264015.0 -45264210.2 -45264407.5 -45264603.8 NRC (Ottawa) 28836.1 28842.6 28843.0 28838.0 28836.9 28849.8 28853.6 NTSC (Lintong) 481.5 494.4 497.6 502.3 506.7 511.9 515.4 PL (Warszawa) -2298.9 -2315.2 -2331.4 -2341.0 -2353.2 -2362.9 -2375.3 PTB (Braunschweig) -359189.4 -359183.6 -359177.1 -359166.8 -359159.9 -359151.5 -359149.5 SU (Moskva) 27240987.2 27240994.9 27240996.0 27241000.0 27241000.8 27240997.7 27240996.0 (1) USNO (Washington DC) -34930644.5 -34930950.5 -34931257.3 -34931564.8 -34931873.6 -34932180.7 -34932488.4 - Note on section 2: (1) SU : Listed values are TAI-TA(SU) - 2.80 seconds. 3 - Difference between the normalized frequencies of EAL (free atomic time scale) and TAI. Interval of validity f(EAL)-f(TAI) Steering Correction 53094 - 53154 6.920x10**-13 (2004 MAR 30 - 2004 MAY 29) New correction 53154 - 53184 6.910x10**-13 (2004 MAY 29 - 2004 JUN 28) New correction foreseen 53184 - 53214 6.904x10**-13 (2004 JUN 28 - 2004 JUL 28) 4 - Duration of the TAI scale interval. TAI is a realization of coordinate time TT. The following tables give the fractional deviation d of the scale interval of TAI from that of TT (the SI second on the geoid), i.e. the fractional frequency deviation of TAI with the opposite sign: d = -yTAI. In this section, a frequency over a time interval is defined as the ratio of the end-point phase difference to the duration of the interval. Whenever needed, the instability of EAL should be expressed as the quadratic sum of three components with t in days: (1) a white frequency noise of 6.0x10**-15 / sqrt(t), (2) a flicker frequency noise of 0.6x10**-15 and (3) a random walk frequency noise of 1.6x10**-16 x sqrt(t). The relation between EAL and TAI is given in Circular T and the Annual Report of the BIPM Time Section. In the first table, d is obtained, on the given periods of estimation by comparison of the TAI frequency with that of the given individual Primary Frequency Standards (PFS). In this table: uA is the uncertainty originating in the instability of the PFS, uB is the combined uncertainty from systematic effects, Ref(uB) is a reference giving information on the stated value of uB or is the Circular T where this reference was first given, ul/lab is the uncertainty in the link between the PFS and the clock participating to TAI, including the uncertainty due to the dead-time, ul/TAI is the uncertainty in the link to TAI, u is the quadratic sum of all four uncertainty values. All values are expressed in 10**-15. Standard Period of d uA uB Ref(uB) ul/Lab ul/Tai u Note Estimation SYRTE-FO2 53109 53129 4.1 0.04 0.6 T183 0.2 1.5 1.6 (1) SYRTE-JPO 53114 53124 4.9 0.7 6.5 T160 0.3 3.0 7.2 (1) SYRTE-FO2 53129 53149 4.9 0.04 0.6 T183 0.2 1.5 1.6 (1) SYRTE-JPO 53124 53144 8.0 0.5 6.5 T160 0.3 1.5 6.7 (1) PTB-CS1 53124 53154 3.5 5.0 8.0 T148 0.0 1.0 9.5 (2) PTB-CS2 53124 53154 1.5 3.0 12.0 T148 0.0 1.0 12.4 (2) Notes: (1) Report on 7 June 2004 by BNM-SYRTE. (2) Continuously operating as a clock participating to TAI. The second table gives the BIPM estimate of d, based on all available PFS measurements over the period MJD 52764-53154, taking into account their individual uncertainties and characterizing the instability of EAL as noted above. u is the computed standard uncertainty of d Period of estimation d u 53124-53154 4.9x10**-15 1.3x10**-15 (2004 APR 29 - 2004 MAY 29) 5 - Relations of UTC and TAI with GPS time and GLONASS time. [UTC-GPS time] = -13 s + C0, [TAI-GPS time] = 19 s + C0, global uncertainty is of order 10 ns. [UTC-GLONASS time] = 0 s + C1, [TAI-GLONASS time] = 32 s + C1, global uncertainty is of order hundreds ns. The C0 values are obtained using the values [UTC-UTC(OP)] and the GPS data taken at the Paris Observatory, corrected for IGS precise orbits, clocks and ionosphere maps. The C1 values are obtained using the values [UTC-UTC(VSL)] and the GLONASS data taken at the NMi Van Swinden Laboratorium (VSL). N0 and N1 are the numbers of measurements. The standard deviations S0 and S1 characterize the dispersion of individual measurements. The actual uncertainty of user's access to GPS and GLONASS times may differ from these values. For this circular, S0 = 1.9 ns, S1 = 29.8 ns Date 2004 0h UTC MJD C0/ns N0 C1/ns N1 APR 29 53124 -12.3 35 299.1 21 APR 30 53125 -11.5 46 303.5 58 MAY 1 53126 -10.3 46 293.3 67 MAY 2 53127 -10.4 46 288.8 68 MAY 3 53128 -10.6 46 299.2 57 MAY 4 53129 -13.5 46 297.9 73 MAY 5 53130 -13.8 19 301.5 72 MAY 6 53131 -14.6 31 301.7 46 MAY 7 53132 -15.8 46 305.7 56 MAY 8 53133 -14.1 46 324.4 59 MAY 9 53134 -12.0 46 317.1 64 MAY 10 53135 -9.7 46 318.9 51 MAY 11 53136 -10.0 45 310.6 62 MAY 12 53137 -12.7 46 305.0 73 MAY 13 53138 -14.5 45 313.5 67 MAY 14 53139 -13.5 44 322.6 65 MAY 15 53140 -14.7 45 317.7 71 MAY 16 53141 -13.9 45 320.3 60 MAY 17 53142 -12.4 45 310.9 65 MAY 18 53143 -13.5 45 311.4 55 MAY 19 53144 -14.7 44 317.0 59 MAY 20 53145 -16.5 42 299.9 63 MAY 21 53146 -15.2 11 300.4 67 MAY 22 53147 -12.5 43 286.2 69 MAY 23 53148 -12.5 44 278.8 78 MAY 24 53149 -13.1 44 276.2 48 MAY 25 53150 -16.8 45 265.8 28 MAY 26 53151 -17.1 45 255.4 31 MAY 27 53152 -16.5 44 272.8 33 MAY 28 53153 -14.9 44 279.5 13 MAY 29 53154 -13.6 46 271.8 9 6 - Time links used for the computation of TAI and their uncertainties. The time links used in the elaboration of this Circular T are listed in this section. The technique for the link is indicated as follows: GPS SC for GPS common-view single-channel C/A data; GPS MC for GPS common-view multi-channel C/A data; GPS P3 for GPS common-view multi-channel dual-frequency P code data; GPS GT for 'GPS time' observations; INT LK for internal cable link and TWSTFT for two-way satellite time and frequency transfer data. For each link, the following uncertainties are provided: uA is the statistical uncertainty evaluated by taking into account the level of phase noise in the raw data, the interpolation interval between data points and the effects with typical duration between 5 and 30 days. uB is the uncertainty on the calibration, estimated by the BIPM. The calibration type of the link is indicated as: GPS EC for GPS equipment calibration; TW EC for two-way equipment calibration; LC (technique) for a link calibrated using 'technique'; BC (technique) for a link calibrated using 'technique' to transfer a past equipment calibration through a discontinuity of link operation. The calibration dates indicate: the most recent calibration results for the two laboratories in the case of EC and the most recent calibration of the link in the case of LC and BC, NA stands for not available, in this case estimated values are provided Link Type uA/ns uB/ns Calibration Type Calibration Dates AOS /PTB GPS MC 1.5 5.0 GPS EC /GPS EC 2003 Sep/2003 Aug APL /USNO GPS MC 1.5 5.0 GPS EC /GPS EC 2003 Dec/2003 Dec AUS /NICT GPS MC 3.0 5.0 GPS EC/GPS EC 2002 Sep/2003 Nov BEV /PTB GPS MC 1.5 5.0 GPS EC/GPS EC 2001 Dec/2003 Aug BIRM/NICT GPS MC 2.5 20.0 NA /GPS EC NA /2003 Nov CAO /PTB GPS SC 7.0 20.0 NA /GPS EC NA /2003 Aug CH /PTB GPS P3 0.7 5.0 GPS EC/GPS EC 2001 Feb/2003 Aug CNM /NIST GPS SC 5.0 20.0 NA /GPS EC NA /2003 Dec CNMP/USNO GPS MC 4.0 7.0 GPS EC/GPS EC 2002 Oct/2003 Dec CSIR/PTB GPS MC 3.0 20.0 NA /GPS EC NA /2003 Aug DLR /PTB GPS P3 0.7 5.0 GPS EC/GPS EC 2003 Apr/2003 Aug DTAG/PTB GPS SC 3.0 10.0 GPS EC/GPS EC 1998 May/2003 Aug HKO /NICT GPS MC 3.0 5.0 GPS EC/GPS EC 2004 Apr/2003 Nov IEN /PTB TWSTFT 1.0 1.0 LC (TWSTFT) 2003 Jun IFAG/PTB GPS P3 0.7 5.0 GPS EC/GPS EC 2003 Jun/2003 Aug IGMA/NIST GPS GT 5.0 20.0 NA /GPS EC NA /2003 Dec INPL/PTB GPS SC 4.0 10.0 GPS EC/GPS EC 1987 Jun/2003 Jun JATC/NTSC INT LK 0.2 20.0 NA NA JV /PTB GPS GT 5.0 20.0 NA /GPS EC NA /2003 Aug KRIS/NICT GPS MC 2.5 5.0 GPS EC/GPS EC 2003 Oct/2003 Nov LDS /PTB GPS SC 3.0 20.0 NA /GPS EC NA /2003 Aug LT /PTB GPS MC 1.5 5.0 GPS EC/GPS EC 2001 Nov/2003 Aug MSL /NICT GPS MC 3.0 20.0 NA /GPS EC NA /2003 Nov NAO /NICT GPS SC 3.0 20.0 NA /GPS EC NA /2003 Nov NICT/PTB GPS MC 2.0 5.0 GPS EC/GPS EC 2003 Nov/2003 Aug NIM /NICT GPS SC 3.0 20.0 NA /GPS EC NA /2003 Nov NIMB/PTB GPS SC 15.0 20.0 NA /GPS EC NA /2003 Aug NIMT/NICT GPS MC 3.0 20.0 NA /GPS EC NA /2003 Nov NIS /PTB GPS MC 3.0 20.0 NA /GPS EC NA /2003 Aug NIST/PTB TWSTFT 0.5 5.0 LC(GPS SC) 2003 Sep NMC /PTB GPS GT 5.0 20.0 NA /GPS EC NA /2003 Aug NMIJ/NICT TWSTFT 1.5 5.0 LC(GPS SC) 2001 Oct NMLS/NICT GPS MC 3.0 20.0 NA /GPS EC NA /2003 Nov NPL /PTB TWSTFT 0.5 5.0 LC(GPS SC) 1999 Nov NPLI/PTB GPS SC 3.0 20.0 NA /GPS EC NA /2003 Aug NRC /USNO GPS SC 3.0 15.0 GPS EC/GPS EC 1982 /2003 Dec NTSC/NICT TWSTFT 1.5 5.0 LC(GPS SC) 2001 Oct OMH /PTB GPS SC 2.5 20.0 NA /GPS EC NA /2003 Aug ONBA/USNO GPS MC 5.0 7.0 GPS EC/GPS EC 2000 Oct/2003 Dec ONRJ/NIST GPS SC 5.0 20.0 NA /GPS EC NA /2003 Dec OP /PTB GPS SC 2.5 5.0 GPS EC/GPS EC 2004 Jan/2003 Aug ORB /PTB GPS P3 0.7 5.0 GPS EC/GPS EC 2003 Jul/2003 Aug PL /PTB GPS MC 1.5 5.0 GPS EC/GPS EC 2001 Oct/2003 Aug ROA /PTB TWSTFT 1.0 5.0 LC(GPS SC) 2001 Dec SCL /NICT GPS SC 4.0 10.0 GPS EC/GPS EC 1993 May/2003 Nov SG /NICT GPS MC 3.0 20.0 NA /GPS EC NA /2003 Nov SMU /PTB GPS SC 5.0 20.0 NA /GPS EC NA /2003 Aug SP /PTB GPS SC 3.0 10.0 GPS EC/GPS EC 1997 Oct/2003 Aug SU /PTB GPS SC 3.0 5.0 GPS EC/GPS EC 2003 Apr/2003 Aug TCC /NIST GPS SC 5.0 20.0 NA /GPS EC NA /2003 Dec TL /NICT TWSTFT 1.5 5.0 LC(GPS SC) 2001 Oct TP /PTB GPS SC 2.5 5.0 GPS EC/GPS EC 2001 Oct/2003 Aug UME /PTB GPS SC 15.0 20.0 NA /GPS EC NA /2003 Aug USNO/PTB TWSTFT 0.5 3.0 BC(GPS P3) 2003 Sep VSL /PTB TWSTFT 1.0 5.0 LC(GPS SC) 1999 Dec