CIRCULAR T 201 ISSN 1143-1393 2004 OCTOBER 11, 12h 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 AUG 27 SEP 1 SEP 6 SEP 11 SEP 16 SEP 21 SEP 26 MJD 53244 53249 53254 53259 53264 53269 53274 Laboratory k [UTC-UTC(k)]/ns AOS (Borowiec) -4.6 -1.3 3.4 -6.9 -9.9 -15.8 -22.7 APL (Laurel) -8.6 -9.0 -13.8 -7.4 -0.1 -9.4 -18.0 AUS (Sydney) -525.3 -516.5 -505.2 -502.6 -495.4 -470.5 -480.9 BEV (Wien) 13.5 15.0 13.2 16.7 20.2 20.8 13.2 BIRM (Beijing) 703.8 718.8 733.2 747.4 755.6 771.0 794.6 CAO (Cagliari) -3555.2 -3522.1 -3509.4 -3516.2 -3504.5 -3486.8 -3493.6 CH (Bern) -18.4 -15.9 -15.5 -17.7 -10.9 -0.5 7.9 CNM (Queretaro) 24.4 10.9 8.1 1.1 4.5 4.2 -3.2 CNMP (Panama) -1221.6 -1244.6 -1278.9 -1294.8 -1315.0 -1362.1 -1380.2 CSIR (Pretoria) -183.6 -261.7 -337.3 -416.3 -496.9 -571.4 -636.1 DLR (Oberpfaffenhofen) - - - - - - - DTAG (Darmstadt) 247.0 234.1 234.1 225.2 219.5 203.8 203.7 (1) HKO (Hong Kong) 339.5 349.8 351.6 355.1 362.2 372.8 373.3 IEN (Torino) 42.4 38.6 38.0 39.4 29.6 23.0 16.0 IFAG (Wettzell) -3061.0 -3078.9 -3083.8 -3091.6 -3096.5 -3105.5 -3100.9 IGMA (Buenos Aires) 135.7 143.4 142.4 146.1 164.2 168.1 170.8 INPL (Jerusalem) -10736.9 -10786.5 -10844.1 -10909.1 -10968.1 -11023.3 -11084.8 JATC (Lintong) -10707.0 -10697.1 -10688.1 -10680.9 -10670.0 -10665.6 -10653.7 JV (Kjeller) -8250.8 -8242.2 -8174.8 -8138.5 -8079.3 -8051.8 -7991.7 KRIS (Daejon) -19.8 4.5 12.2 10.8 17.0 23.3 23.9 LDS (Leeds) 1018.1 1042.4 1074.8 1101.8 1120.0 1152.6 1178.2 LT (Vilnius) 250.1 269.4 281.0 302.5 324.8 326.4 317.3 MSL (Lower Hutt) -120.6 -118.8 -123.3 -80.9 -70.3 -58.2 -36.9 NAO (Mizusawa) -206.1 -201.6 -215.0 -208.9 -207.5 -213.7 -219.2 NICT (Tokyo) 15.8 14.9 13.7 16.4 11.1 10.2 10.0 NIM (Beijing) -2651.0 -2655.7 -2654.7 -2658.5 -2666.2 -2658.3 -2657.5 NIMB (Bucharest) - - - - - - - NIMT (Bangkok) -1599.3 -1620.3 -1638.9 -1654.9 -1683.0 -1712.6 -1739.9 (2) NIS (Cairo) 564.8 588.9 600.3 623.9 662.7 554.2 608.6 NIST (Boulder) 2.4 2.5 3.7 4.7 4.2 4.1 3.6 NMC (Sofiya) -4338.8 -4349.9 -4361.6 -4386.2 -4402.2 -4411.1 -4426.8 NMIJ (Tsukuba) 24.5 8.6 0.4 0.9 -2.5 -7.0 -12.8 NMLS (Shah Alam) - - - - - - - NPL (Teddington) -26.4 -27.3 -29.3 -29.5 -30.5 -30.8 -30.7 NPLI (New-Delhi) 8341.7 8392.4 8423.9 8458.6 8491.0 8526.7 8570.8 NRC (Ottawa) 7.9 9.3 5.7 4.0 3.8 10.9 6.9 NTSC (Lintong) 17.4 24.1 20.6 23.2 12.9 6.4 3.7 OMH (Budapest) 9307.1 9341.6 9354.3 9370.4 9375.3 9406.7 9434.3 ONBA (Buenos Aires) -347.8 -445.2 -436.8 -365.2 -349.7 -294.2 -332.0 ONRJ (Rio de Janeiro) 2576.3 2767.8 2997.3 3237.3 3475.3 3733.3 3958.8 OP (Paris) -5.3 -4.5 -0.5 -7.3 -10.6 -13.3 -10.9 ORB (Bruxelles) -58.1 -59.6 -61.7 -63.8 -64.2 -62.7 -59.2 PL (Warszawa) -48.2 -46.8 -45.9 -45.3 -41.5 -42.4 -41.5 PTB (Braunschweig) -9.5 -4.1 -1.8 3.4 1.9 4.7 10.9 ROA (San Fernando) -0.2 1.1 1.6 3.8 1.9 1.3 -3.4 SCL (Hong Kong) -8.4 -13.2 -20.8 -23.5 -10.6 -6.5 -7.5 SG (Singapore) -15.6 -20.1 -18.4 -14.8 -20.4 -6.2 -10.6 SMU (Bratislava) -70.9 -83.5 -102.4 -110.9 -123.1 -139.9 -156.5 SP (Boras) 517.4 519.7 521.4 526.2 531.5 531.4 543.6 SU (Moskva) 50.3 54.5 54.6 59.2 63.9 66.0 71.3 TCC (Concepcion) -8481.9 -8556.1 -8591.1 -8679.7 -8765.5 -8818.6 -8875.3 TL (Chung-Li) 46.4 44.6 40.6 45.5 37.4 33.7 35.4 TP (Praha) -37.2 -28.5 -34.7 -33.8 -32.0 -31.4 -32.0 UME (Gebze-Kocaeli) 312.8 308.6 313.1 317.3 320.1 319.3 324.6 USNO (Washington DC) -1.5 -1.9 -2.9 -4.5 -5.4 -5.2 -6.3 VSL (Delft) -77.3 -76.4 -74.5 -79.2 -71.5 -69.3 -64.7 - Notes on section 1: (1) DTAG: Correction to Circular T 200 note (2): No time step of [UTC-UTC(DTAG)] between MJD 53239 and 53244. Value of [UTC-UTC(DTAG)] for MJD 53244 corrected in this Circular T. (2) NIMT: Corrected values /ns MJD UTC-UTC(NIMT) 53219 -1511.1 53224 -1525.3 53229 -1539.9 53234 -1561.4 53239 -1576.3 2 - International Atomic Time TAI and Local atomic time scales TA(k). Computed values of [TAI-TA(k)]. Date 2004 0h UTC AUG 27 SEP 1 SEP 6 SEP 11 SEP 16 SEP 21 SEP 26 MJD 53244 53249 53254 53259 53264 53269 53274 Laboratory k [TAI-TA(k)]/ns CH (Bern) 45740.2 45844.9 45947.6 46047.6 46150.3 46252.5 46352.6 F (Paris) 169206.5 169199.8 169194.4 169187.1 169182.3 169173.9 169170.5 IEN (Torino) 38418.6 38523.8 38640.1 38752.5 38866.0 38979.2 39094.6 JATC (Lintong) -35704.0 -35746.1 -35786.1 -35826.9 -35864.0 -35898.6 -35943.7 KRIS (Taejon) 7646.8 7692.0 7722.5 7745.3 7774.9 7804.1 7828.5 NICT (Tokyo) 191828.0 192039.4 192249.4 192460.7 192672.2 192882.5 193092.3 NIST (Boulder) -45268132.0 -45268328.4 -45268523.7 -45268719.2 -45268915.2 -45269110.8 -45269306.8 NRC (Ottawa) 28915.1 28920.5 28921.7 28924.2 28928.4 28940.1 28939.5 NTSC (Lintong) 588.8 593.7 594.1 597.7 602.5 604.8 606.0 PL (Warszawa) -2569.2 -2580.8 -2589.9 -2599.3 -2608.5 -2619.4 -2628.5 PTB (Braunschweig) -359045.1 -359034.7 -359027.0 -359017.2 -359013.6 -359005.8 -358994.4 SU (Moskva) 27241050.3 27241054.5 27241054.6 27241059.2 27241063.9 27241066.0 27241071.3 (1) USNO (Washington DC) -34938022.0 -34938329.6 -34938635.5 -34938943.4 -34939250.1 -34939556.8 -34939865.2 - 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 53244 - 53274 6.893x10**-13 (2004 AUG 27 - 2004 SEP 26) New correction 53274 - 53309 6.893x10**-13 (2004 SEP 26 - 2004 OCT 31) New correction foreseen 53309 - 53339 6.893x10**-13 (2004 OCT 31 - 2004 NOV 30) 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 PTB-CS1 53244 53274 -4.6 5.0 8.0 T148 0.0 1.0 9.5 (1) PTB-CS2 53244 53274 -3.0 3.0 12.0 T148 0.0 1.0 12.4 (1) Notes: (1) 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 52884-53274, 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 53244-53274 2.1x10**-15 2.5x10**-15 (2004 AUG 27 - 2004 SEP 26) 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 = 28.0 ns Date 2004 0h UTC MJD C0/ns N0 C1/ns N1 AUG 27 53244 -10.2 39 310.0 67 AUG 28 53245 -13.2 37 298.1 51 AUG 29 53246 -14.8 40 294.9 68 AUG 30 53247 -14.8 40 313.2 33 AUG 31 53248 -13.4 39 312.9 7 SEP 1 53249 -14.6 37 304.1 79 SEP 2 53250 -15.7 41 299.4 81 SEP 3 53251 -14.0 39 300.4 69 SEP 4 53252 -12.7 36 303.1 55 SEP 5 53253 -13.1 37 301.0 57 SEP 6 53254 -11.6 36 304.1 55 SEP 7 53255 -9.6 39 315.5 62 SEP 8 53256 -8.3 41 308.0 65 SEP 9 53257 -8.2 40 294.7 79 SEP 10 53258 -14.4 39 287.3 77 SEP 11 53259 -17.1 39 274.8 83 SEP 12 53260 -19.1 37 283.5 71 SEP 13 53261 -20.8 38 299.9 61 SEP 14 53262 -22.4 32 300.9 65 SEP 15 53263 -24.5 41 299.7 64 SEP 16 53264 -22.6 40 304.8 68 SEP 17 53265 -20.0 23 301.5 71 SEP 18 53266 -16.9 39 297.7 75 SEP 19 53267 -17.0 41 288.4 72 SEP 20 53268 -18.5 41 290.5 68 SEP 21 53269 -18.6 40 305.0 55 SEP 22 53270 -16.0 38 299.1 62 SEP 23 53271 -13.2 40 302.9 53 SEP 24 53272 -15.7 40 288.1 64 SEP 25 53273 -16.1 41 287.5 76 SEP 26 53274 -15.4 41 282.9 71 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 NA 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/USNO GPS MC 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 Link Type uA/ns uB/ns Calibration Type Calibration Dates 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 P3 1.5 20.0 NA /GPS EC NA /2003 Oct NAO /NICT GPS SC 3.0 20.0 NA /GPS EC NA /2003 Nov NICT/PTB GPS P3 1.5 5.0 LC(GPS MC) 2004 May NIM /NICT GPS SC 3.0 20.0 NA /GPS EC NA /2003 Nov NIMB NA NIMT/NICT GPS P3 1.5 20.0 NA /GPS EC NA /2003 Oct 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 GPS SC 2.5 5.0 GPS EC/GPS EC 2002 Apr/2003 Oct NMLS NA 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 GPS MC 2.5 5.0 GPS EC/GPS EC 2002 Aug/2003 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