ISSN 1143-1393 Cicular T 135 (1999 April 16) Circulaire T 135 1 - Coordinated Universal Time UTC. Computed values of UTC-UTC(k). (From 1999 January 1, 0h UTC, TAI-UTC = 32 s) Date 1999 0h UTC Feb 25 Mar 2 Mar 7 Mar 12 MJD 51234 51239 51244 51249 Laboratory k UTC-UTC(k) (Unit is one nanosecond) AOS (Borowiec) -9137 -9018 -9030 -9001 APL (Laurel) -83 -110 -75 -117 AUS (Sydney) 1229 1272 1299 1315 BEV (Wien) 7681 7844 7998 8157 BIRM (Beijing) -12119 -12149 -12221 -12248 CAO (Cagliari) -3885 -3898 -3895 -3919 CH (Bern) 184 166 143 128 CNM (Queretaro) 1653 1679 1706 1731 CRL (Tokyo) 34 38 36 39 CSAO (Lintong) -39 -22 -18 -22 CSIR (Pretoria) 6320 6256 6213 6143 DLR (Oberpfaffenhofen) -6813 -6895 -6980 -7068 DTAG (Darmstadt) 36 22 23 25 GUM (Warszawa) 1462 1474 1486 1495 IEN (Torino) -30 -31 -47 -51 IFAG (Wettzell) -2390 -2401 -2389 -2398 IGMA (Buenos Aires) 109 88 100 71 INPL (Jerusalem) -105 -114 -121 -128 IPQ (Monte de Caparica) - - - - JATC (Lintong) -338 -342 -375 -397 KRIS (Taejon) 269 274 271 272 LDS (Leeds) 923 926 939 942 MSL (Lower Hutt) -360 -253 -108 -70 NAO (Mizusawa) 210 178 137 101 NIM (Beijing) -3056 -3072 -3062 -3063 NIST (Boulder) 26 24 21 21 NPL (Teddington) 54 53 55 54 NPLI (New-Delhi) 1802 1839 1889 - NRC (Ottawa) -26 -19 -24 -26 NRLM (Tsukuba) 1182 1198 1209 1222 OMH (Budapest) 2960 2968 2989 2986 ONBA (Buenos Aires) 226 189 73 -122 ONRJ (Rio de Janeiro) 1607 1616 1631 1638 OP (Paris) -22 -22 -19 -13 ORB (Bruxelles) 296 291 313 297 PSB (Singapore) 1370 1405 1440 1477 PTB (Braunschweig) -16 -21 -23 -22 ROA (San Fernando) -9 -11 -7 -4 SCL (Hong Kong) -53 -39 -50 -47 SMU (Bratislava) -1637 -1649 -1653 -1654 SO (Shanghai) 725 735 734 739 SP (Boras) 437 418 400 383 SU (Moskva) 121 116 110 110 TL (Chung-Li) 195 208 198 204 TP (Praha) 227 231 224 227 TUG (Graz) -114 -126 -135 -139 UME (Gebze-Kocaeli) 1829 1829 1829 1827 USNO (Washington DC)(USNO MC) 7 6 5 4 VSL (Delft) 19 15 10 12 BIPM , T 135 (2) 1 - Coordinated Universal Time UTC. (Cont.) Date 1999 0h UTC Mar 17 Mar 22 Mar 27 MJD 51254 51259 51264 Laboratory k UTC-UTC(k) (Unit is one nanosecond) AOS (Borowiec) -8820 -8689 -8663 APL (Laurel) -173 -257 -322 AUS (Sydney) 1345 1351 1370 BEV (Wien) 8306 8467 8628 BIRM (Beijing) -12311 -12420 -12428 CAO (Cagliari) -3905 -3895 -3897 CH (Bern) 103 79 58 CNM (Queretaro) 1755 1774 1802 CRL (Tokyo) 35 33 41 CSAO (Lintong) -21 -20 -10 CSIR (Pretoria) 6081 6016 5977 DLR (Oberpfaffenhofen) -7153 -7235 -7333 DTAG (Darmstadt) 21 26 31 GUM (Warszawa) 1506 1516 1529 IEN (Torino) -50 -53 -58 IFAG (Wettzell) -2412 -2425 -2432 IGMA (Buenos Aires) 49 42 64 INPL (Jerusalem) -137 -144 -149 IPQ (Monte de Caparica) - - - JATC (Lintong) -419 -439 -443 KRIS (Taejon) 274 281 282 LDS (Leeds) 941 960 970 MSL (Lower Hutt) -47 -80 -81 NAO (Mizusawa) 72 37 -3 NIM (Beijing) -3096 -3101 -3080 NIST (Boulder) 17 15 13 NPL (Teddington) 51 52 53 NPLI (New-Delhi) - - - NRC (Ottawa) -35 -39 -42 NRLM (Tsukuba) 1237 1245 1260 OMH (Budapest) 2998 3000 3012 ONBA (Buenos Aires) -103 -126 91 ONRJ (Rio de Janeiro) 1660 1671 1682 OP (Paris) -18 -21 -23 ORB (Bruxelles) 308 321 315 PSB (Singapore) (1) 1511 473 496 PTB (Braunschweig) -23 -22 -24 ROA (San Fernando) -1 2 1 SCL (Hong Kong) -39 -34 -39 SMU (Bratislava) -1665 -1690 -1702 SO (Shanghai) 712 706 721 SP (Boras) 374 369 359 SU (Moskva) 110 109 108 TL (Chung-Li) 213 213 214 TP (Praha) 229 221 229 TUG (Graz) -138 -148 -155 UME (Gebze-Kocaeli) 1828 1826 1828 USNO (Washington DC)(USNO MC) 1 3 4 VSL (Delft) -2 2 -4 BIPM , T 135 (3) 2 - International Atomic Time TAI and local atomic time scales TA(k). The following table gives the computed values of TAI-TA(k). Date 1999 0h UTC Feb 25 Mar 2 Mar 7 Mar 12 MJD 51234 51239 51244 51249 Laboratory k TAI-TA(k) (Unit is one nanosecond) AMC (Col. Springs) -365540 -365548 -365552 -365559 APL (Laurel) 1380 1353 1388 1346 AUS (Sydney) -91850 -91937 -92032 -92152 CH (Bern) -24428 -24243 -24063 -23875 CRL (Tokyo) 112122 112335 112555 112766 CSAO (Lintong) -253 -241 -249 -255 F (Paris) 162671 162676 162675 162681 IEN (Torino) 8767 8787 8806 8829 INPL (Jerusalem) -105 -114 -121 -128 JATC (Lintong) 400 316 219 116 KRIS (Taejon) 6137 6138 6127 6126 NIST (Boulder) -45187737 -45187943 -45188149 -45188351 NRC (Ottawa) 26919 26918 26912 26910 PTB (Braunschweig) -360985 -360983 -360977 -360969 SU (Moskva) (2) 27241121 27241116 27241110 27241110 USNO (Washington DC) -34812656 -34812968 -34813281 -34813594 Date 1999 0h UTC Mar 17 Mar 22 Mar 27 MJD 51254 51259 51264 Laboratory k TAI-TA(k) (Unit is one nanosecond) AMC (Col. Springs) -365568 -365571 -365576 APL (Laurel) 1290 1206 1141 AUS (Sydney) -92256 -92372 -92481 CH (Bern) -23697 -23517 -23335 CRL (Tokyo) 112985 113199 113419 CSAO (Lintong) -262 -265 -258 F (Paris) 162681 162680 162680 IEN (Torino) 8851 8875 8892 INPL (Jerusalem) -137 -144 -149 JATC (Lintong) 17 -81 -171 KRIS (Taejon) 6126 6135 6137 NIST (Boulder) -45188558 -45188762 -45188967 NRC (Ottawa) 26902 26898 26895 PTB (Braunschweig) -360962 -360954 -360948 SU (Moskva) (2) 27241110 27241109 27241108 USNO (Washington DC) -34813911 -34814223 -34814536 BIPM , T 135 (4) 3 - Notes on sections 1 and 2. (1) PSB . Apparent time step of UTC-UTC(PSB) between MJD = 51254 and MJD = 51259 due to a power supply failure at PSB. (2) SU . Listed values are TAI-TA(SU) - 2.80 seconds. 4 - Difference between the normalized frequencies of EAL and TAI. Interval of validity f(EAL)-f(TAI) 1999 Feb. 25 - 1999 Mar. 27 51234-51264 7.140x10**-13 No new steering correction foreseen for April and May 1999 1999 Mar. 27 - 1999 May 31 51264-51329 7.140x10**-13 5 - Duration of the TAI scale interval. The following table gives the duration uTAI of the TAI scale interval expressed as its relative departure d from the SI second on the rotating geoid, u0, together with its uncertainty s : d = (uTAI-u0)/u0. This is obtained, on the given period of estimation, by comparison of the TAI frequency : - with the frequency of a given individual primary frequency standard (s is then the last communicated estimate of the type B uncertainty of the standard), and - with a combination computed by the BIPM of measurements from CRL-01, NIST-7, NRLM-4, PTB CS1, PTB CS2 and PTB CS3 (s is then estimated by the BIPM taking into account the individual uncertainties and parameters characteristic of TAI stability). Standard Period of d s estimation (10**-14) (10**-14) NIST-7 51209-51239 +0.1 1.0 NRLM-4 51219-51229 -4.3 2.9 PTB CS1 51234-51264 +0.1 0.7 PTB CS2 51234-51264 +0.2 1.5 PTB CS3 51234-51264 +3.9 1.4 BIPM estimate 51209-51264 -0.1 1.0 BIPM , T 135 (5) 6 - [UTC-GPS time] and [TAI-GPS time]. [UTC-GPS time] = -13 s + C0, [TAI-GPS time] = 19 s + C0. Daily values of C0 are given in the following table. They are obtained as follows: the GPS data taken at the Paris Observatory, for highest elevation, are first corrected for precise satellite ephemerides and for measured ionospheric delays, and then smoothed to obtain daily values of [UTC(OP)-GPS time] at 0h UTC; daily values of C0 are derived from them using linear interpolation of [UTC-UTC(OP)]. The global uncertainty of daily C0 values is of order 10 ns. In the following table, the standard deviation s characterizes the dispersion of individual measurements, and N is the number of measurements used on a given day for estimation of the corresponding daily C0 value. Date 1999 MJD C0 s s/sqrt(N) 0h UTC (ns) (ns) (ns) Feb 25 51234 -2 40 6 Feb 26 51235 -7 34 5 Feb 27 51236 -9 43 7 Feb 28 51237 -7 47 7 Mar 1 51238 -4 50 8 Mar 2 51239 -3 44 7 Mar 3 51240 -1 46 7 Mar 4 51241 1 47 7 Mar 5 51242 4 44 7 Mar 6 51243 2 48 8 Mar 7 51244 -2 41 6 Mar 8 51245 -5 44 7 Mar 9 51246 -4 56 9 Mar 10 51247 3 41 6 Mar 11 51248 7 36 6 Mar 12 51249 6 45 7 Mar 13 51250 4 50 8 Mar 14 51251 3 44 7 Mar 15 51252 2 42 7 Mar 16 51253 -2 44 7 Mar 17 51254 -8 40 7 Mar 18 51255 -11 46 8 Mar 19 51256 -11 40 6 Mar 20 51257 -9 47 8 Mar 21 51258 -6 49 8 Mar 22 51259 -7 46 7 Mar 23 51260 -6 49 8 Mar 24 51261 2 49 8 Mar 25 51262 10 42 7 Mar 26 51263 8 37 6 Mar 27 51264 0 43 7 BIPM , T 135 (6) 7 - [UTC-GLONASS time] and [TAI-GLONASS time]. [UTC-GLONASS time] = 0 s + C1, [TAI-GLONASS time] = +32 s + C1. Daily values of C1 are given in the following table. They are obtained as follows: the GLONASS data taken at the NMi Van Swinden Laboratorium, Delft, The Netherlands, for highest elevation, are smoothed to obtain daily values of [UTC(VSL)-GLONASS time] at 0h UTC; daily values of C1 are then derived from them using linear interpolation of [UTC-UTC(VSL)]. To ensure the continuity of C1 estimates, the following time corrections are applied : + 1285 ns from 1997, January 1 (MJD=50449) to 1999, March 22 (MJD=51259) + 107 ns for 1999, March 23 and March 24 (MJD=51260 and MJD=51261) + 0 ns since 1999, March 25 (MJD=51262). The global uncertainty of daily C1 values is of order several hundreds of nanoseconds. In the following table, the standard deviation s characterizes the dispersion of individual measurements, and N is the number of measurements used on a given day for estimation of the corresponding daily C1 value. Date 1999 MJD C1 s s/sqrt(N) 0h UTC (ns) (ns) (ns) Feb 25 51234 236 17 3 Feb 26 51235 232 20 4 Feb 27 51236 226 20 3 Feb 28 51237 219 25 7 Mar 1 51238 212 12 2 Mar 2 51239 222 18 3 Mar 3 51240 245 14 2 Mar 4 51241 255 20 3 Mar 5 51242 246 22 4 Mar 6 51243 240 21 4 Mar 7 51244 248 18 3 Mar 8 51245 264 17 4 Mar 9 51246 266 21 3 Mar 10 51247 240 19 3 Mar 11 51248 218 22 4 Mar 12 51249 212 - - Mar 13 51250 216 15 3 Mar 14 51251 228 23 4 Mar 15 51252 231 18 3 Mar 16 51253 219 25 6 Mar 17 51254 207 17 3 Mar 18 51255 215 21 3 Mar 19 51256 222 18 3 Mar 20 51257 218 20 3 Mar 21 51258 212 25 5 Mar 22 51259 210 17 3 Mar 23 51260 211 19 3 Mar 24 51261 212 15 4 Mar 25 51262 205 21 5 Mar 26 51263 210 23 4 Mar 27 51264 217 18 3