CIRCULAR T 383 ISSN 1143-1393
2019 DECEMBER 09, 10h UTC
BUREAU INTERNATIONAL DES POIDS ET MESURES
THE INTERGOVERNMENTAL ORGANIZATION ESTABLISHED BY THE METRE CONVENTION
PAVILLON DE BRETEUIL F-92312 SEVRES CEDEX TEL. +33 1 45 07 70 70 tai@bipm.org

The contents of the sections of BIPM Circular T are fully described in the document " Explanatory supplement to BIPM Circular T "
available at ftp://ftp2.bipm.org/pub/tai/publication/notes/explanatory_supplement_v0.2.pdf

1 - Difference between UTC and its local realizations UTC(k) and corresponding uncertainties. From 2017 January 1, 0h UTC, TAI-UTC = 37 s.
Date 2019 0h UTC OCT 28 NOV 2 NOV 7 NOV 12 NOV 17 NOV 22 NOV 27 Uncertainty/ns Notes
MJD 58784 58789 58794 58799 58804 58809 58814 uA uB u
Laboratory k [UTC-UTC(k)]/ns
AOS (Borowiec) 9.0 8.4 8.3 7.9 7.6 7.2 6.4 0.3 4.2 4.3
APL (Laurel) 1.2 1.9 0.0 -2.9 -3.1 -0.9 0.2 0.3 11.1 11.1
AUS (Sydney) -353.9 -362.2 -351.8 -357.2 -363.4 -362.5 -371.4 0.3 6.5 6.5
BEV (Wien) -21.2 -20.3 -21.9 -13.0 -9.4 -5.8 -0.6 0.5 3.4 3.4
BIM (Sofiya) 11795.3 11802.0 11816.6 11818.5 11841.1 11854.1 11897.0 0.7 7.1 7.2
BIRM (Beijing) - 9.2 4.4 1.5 1.2 3.9 -3.6 0.3 2.9 2.9
BOM (Skopje) -2678.0 - -2768.5 -2792.5 -2819.7 -2847.5 -2859.6 1.5 8.5 8.7
BY (Minsk) -1.8 -1.4 -0.7 -0.7 0.0 0.8 0.2 1.5 12.2 12.3
CAO (Cagliari) - -15356.7 -15475.1 -15586.0 -15696.4 -15803.8 -15910.5 1.5 20.0 20.1
CH (Bern-Wabern) 10.4 9.0 8.3 7.7 5.6 4.3 3.5 0.3 2.3 2.3
CNES (Toulouse) 0.5 0.5 -0.3 -1.4 -2.0 -1.4 -1.2 0.3 2.9 2.9
CNM (Queretaro) -1.9 6.6 -2.2 -2.0 -8.4 0.6 -2.1 2.5 11.2 11.5
CNMP (Panama) -7.6 7.5 20.2 -17.9 -20.1 7.7 -2.1 0.7 7.4 7.5
DFNT (Tunis) 13716.1 13922.2 14139.7 14362.1 14583.9 14793.5 15025.6 0.7 20.0 20.0
DLR (Oberpfaffenhofen) - - 1116.3 1127.5 1142.6 1155.9 - 0.7 3.5 3.5
DMDM (Belgrade) -3.7 -3.1 -1.4 5.0 6.9 4.1 4.8 0.3 3.5 3.5
DTAG (Frankfurt/M) -87.4 -5.9 -8.2 -6.4 -3.1 4.6 7.8 0.3 2.9 2.9 (1)
EIM (Thessaloniki) -2.3 1.8 6.8 9.1 4.8 -1.4 -3.4 3.0 11.2 11.6
ESTC (Noordwijk) 0.2 0.1 0.7 1.0 1.2 1.7 1.1 0.3 3.1 3.2
HKO (Hong Kong) 110.4 111.2 120.4 127.8 132.0 138.4 144.9 1.0 2.9 3.0
ICE (San Jose) -60.9 -61.4 -37.9 -29.6 -1.5 5.6 0.8 5.0 20.0 20.6
IDN (Serpong-Tangerang) 1483.3 1506.9 1509.9 1538.2 1546.7 1552.2 1561.2 0.7 2.9 3.0
IFAG (Wettzell) -817.8 -810.2 -811.7 -814.8 -807.5 -814.4 -818.6 0.3 2.9 2.9
IGNA (Buenos Aires) -11.6 -21.9 - - - - - 0.3 20.0 20.0
IMBH (Sarajevo) 2.5 -2.0 0.8 5.0 3.3 -1.2 -1.0 0.3 2.9 2.9
INCP (Lima) 118.3 120.2 109.9 103.7 102.5 129.5 110.4 5.0 20.0 20.6
INM (Bogota D.C.) -7.3 -3.0 2.6 12.7 7.3 4.0 1.6 2.0 20.0 20.1
INPL (Jerusalem) 0.2 -1.3 0.9 3.8 8.7 6.4 10.3 0.3 7.3 7.3
INTI (Buenos Aires) 85.6 87.9 99.7 101.3 104.9 91.0 93.0 2.5 20.0 20.2
INXE (Rio de Janeiro) -18.0 - -8.1 -7.0 -4.5 -9.5 -13.4 0.3 20.0 20.0
IPQ (Caparica) 220.1 203.7 188.9 186.0 186.6 192.5 194.6 0.4 20.0 20.0
IT (Torino) 4.8 5.4 6.0 7.3 5.2 2.0 -1.2 0.3 1.5 1.5
JATC (Lintong) 1.4 0.7 -2.4 -1.3 -2.1 -2.1 -1.7 0.3 2.9 2.9
JV (Kjeller) -15.7 -11.0 -12.0 -11.0 -14.5 -22.8 -25.6 0.3 4.2 4.2
KRIS (Daejeon) 7.3 10.3 12.2 12.6 13.6 15.3 16.4 0.3 3.2 3.2
LRTE (Sao Carlos) -6.7 -4.6 -2.8 -5.3 1.8 7.7 10.7 0.3 20.0 20.0
LT (Vilnius) 958.7 998.8 1012.3 1044.6 1040.7 1053.3 1042.5 0.3 2.9 2.9
LUX (Belvaux) 0.2 -3.4 -2.7 -0.6 12.0 14.2 8.3 0.3 2.9 2.9
MASM (Bayanzurkh) -306.3 -327.4 - - -413.9 - - 0.7 2.9 3.0
MBM (Podgorica) - - - - - - -
MIKE (Espoo) 0.9 0.8 0.8 0.5 -0.1 -1.0 -1.7 0.3 4.6 4.6
MKEH (Budapest) - - - - - - 178.7 1.5 20.0 20.1
MSL (Lower Hutt) 421.6 440.8 445.5 455.5 458.3 449.4 438.5 1.5 20.0 20.1
NAO (Mizusawa) -823.4 -836.1 -839.3 1352.2 1344.2 1330.1 1319.6 2.0 19.9 20.0 (2)
NICT (Tokyo) 2.4 1.7 0.9 1.8 4.9 5.7 4.8 0.3 2.0 2.0
NIM (Beijing) 2.6 1.7 1.6 0.9 0.5 0.4 0.5 0.3 1.9 2.0
NIMB (Bucharest) 7377.4 7424.1 7464.7 7514.8 7569.6 7622.2 7659.5 0.4 7.5 7.5
NIMT (Pathumthani) - - - - - - -
NIS (Cairo) -5.1 -10.8 -12.6 -20.6 -11.5 -5.9 -9.7 1.0 20.0 20.0
NIST (Boulder) 1.7 0.8 -0.3 0.1 0.8 0.7 0.5 0.3 1.8 1.9
NMIJ (Tsukuba) 1.0 0.8 1.7 0.6 1.0 1.3 2.2 0.3 3.6 3.6
NMLS (Sepang) -1150.2 -1176.1 -1197.4 -1224.3 -1257.5 -1278.4 -1310.2 1.5 4.0 4.3
NPL (Teddington) 1.9 1.2 0.9 0.9 0.8 1.1 2.2 0.3 3.2 3.2
NPLI (New-Delhi) -1.1 -0.5 2.4 6.3 9.8 13.8 16.0 0.3 2.8 2.8
NRC (Ottawa) -3.3 -7.8 -9.8 -12.6 -9.0 -6.8 1.0 0.3 3.0 3.1
NRL (Washington DC) -1.8 4.9 2.3 0.1 1.1 -1.8 -0.7 0.3 20.0 20.0
NTSC (Lintong) 1.5 0.9 -1.6 -0.8 -1.2 -1.0 -0.3 0.3 2.6 2.6
ONBA (Buenos Aires) 234.7 227.5 238.7 256.8 283.1 295.4 302.3 2.0 11.2 11.4
ONRJ (Rio de Janeiro) 0.2 -7.3 -7.7 -1.6 6.6 0.8 1.4 2.5 20.0 20.1
OP (Paris) 2.3 2.2 2.2 2.0 1.8 1.6 1.4 0.3 1.5 1.5
ORB (Bruxelles) -1.1 -1.6 -2.0 -2.3 -2.4 -2.2 -1.6 0.3 3.1 3.1
PL (Warszawa) -1.2 -5.3 -9.0 -14.1 -19.3 -24.0 -29.2 0.3 2.9 2.9
PTB (Braunschweig) 2.8 2.9 2.9 2.9 2.6 2.5 2.4 0.1 0.6 0.6
ROA (San Fernando) -2.6 -2.4 -2.1 -2.0 -2.0 -3.1 -3.2 0.3 1.9 1.9
SASO (Riyadh) -858.2 -875.3 -880.3 -894.6 -911.1 -929.2 -945.1 0.4 3.0 3.0
SCL (Hong Kong) -28.1 -31.1 -28.9 -25.9 -19.5 -9.1 -2.3 1.0 2.9 3.0
SG (Singapore) - 19.4 18.6 16.5 15.9 18.0 22.0 0.3 2.9 2.9
SIQ (Ljubljana) 122.7 145.8 128.6 120.4 97.5 107.7 107.8 0.3 7.6 7.6
SL (Colombo) 141.0 145.8 141.7 142.4 140.6 131.3 - 0.3 2.9 2.9
SMD (Bruxelles) 10.0 10.3 9.7 10.2 3.5 -1.1 4.0 0.3 3.1 3.2
SMU (Bratislava) -55.6 -60.3 -69.1 -64.2 - -68.7 -68.1 1.5 12.2 12.3
SP (Boras) 3.7 3.9 4.3 4.8 5.6 6.5 7.0 0.5 1.5 1.5
SU (Moskva) 1.5 2.1 2.1 2.1 2.0 2.4 2.4 0.7 1.9 2.1
TL (Chung-Li) 1.6 1.2 0.8 0.5 0.3 -0.2 -0.5 0.3 2.0 2.0
TP (Praha) 30.5 32.7 18.5 8.1 7.8 6.8 17.8 0.3 4.2 4.3
UA (Kharkov) -13.5 -6.8 2.7 11.7 16.0 7.8 -3.9 1.5 9.3 9.4
UAE (Abu Dhabi) 10.2 12.1 16.1 13.9 10.6 12.7 11.9 4.0 8.8 9.7
UME (Gebze-Kocaeli) -104.0 -78.0 -70.7 -62.5 -60.6 -47.9 -42.7 0.5 3.4 3.5 (3)
USNO (Washington DC) 0.4 -0.5 -0.8 -0.9 -0.9 -0.6 0.1 0.2 1.2 1.2
VMI (Ha Noi) -28.3 -26.1 -17.5 -12.3 -18.6 -16.5 -17.5 2.0 4.0 4.5
VSL (Delft) 3.2 4.0 3.0 -3.4 -8.0 -4.8 -5.3 0.3 1.7 1.7
ZA (Pretoria) 1.4 -0.6 -3.3 -4.7 -1.7 1.3 1.9 0.3 2.8 2.9
- Notes on section 1:
(1) DTAG : Apparent time step of UTC(DTAG) of -76ns on MJD 58787 due to calibration.
(2) NAO : Apparent time step of UTC(NAO) of about -2200ns on MJD 58795.
(3) UME : Apparent time step of UTC(UME) of about -11.5ns between MJD 58784 and 58789 due to calibration.

2 - Difference between the normalized frequencies of EAL and TAI.
Interval of validity f(EAL)-f(TAI)
Steering correction 58784 - 58814 6.493x10-13 (2019 OCT 28 - 2019 NOV 27)
New correction 58814 - 58844 6.493x10-13 (2019 NOV 27 - 2019 DEC 27)
New correction foreseen 58844 - 58879 6.493x10-13 (2019 DEC 27 - 2020 JAN 31)

3 - Duration of the TAI scale interval d.

Table 1: Estimate of d by individual PSFS measurements and corresponding uncertainties.
All values are expressed in 10-15 and are valid only for the stated period of estimation.
Standard Period of d uA uB ul/lab ul/Tai u uSrep Ref(uS) Ref(uB) uB(Ref) Steer Note
Estimation
PTB-CS1 58784 58814 4.07 8.00 8.00 0.00 0.07 11.31 PFS/NA T148 8. Y (1)
PTB-CS2 58784 58814 -3.45 5.00 12.00 0.00 0.07 13.00 PFS/NA T148 12. Y (1)
IT-Yb1 58389 58419 0.17 0.01 0.03 0.32 0.26 0.41 0.5 [1] [2] 0.03 Y (2)
IT-Yb1 58419 58434 0.14 0.01 0.03 0.57 0.49 0.75 0.5 [1] [2] 0.03 Y (2)
IT-Yb1 58459 58469 -0.10 0.01 0.03 0.59 0.70 0.92 0.5 [1] [2] 0.03 Y (2)
IT-Yb1 58489 58514 0.65 0.01 0.03 0.39 0.31 0.50 0.5 [1] [2] 0.03 Y (2)
IT-Yb1 58514 58539 0.75 0.01 0.03 0.26 0.31 0.40 0.5 [1] [2] 0.03 Y (2)
NIM5 58764 58784 -0.14 0.20 0.90 0.20 0.28 0.98 PFS/NA T340 1.40 Y (3)
SYRTE-FO1 58789 58814 -0.62 0.30 0.32 0.06 0.23 0.50 PFS/NA T301 0.37 Y (4)
SYRTE-FO2 58789 58814 -0.51 0.30 0.22 0.09 0.23 0.45 PFS/NA T301 0.23 Y (4)
SYRTE-FOM 58789 58814 -0.44 0.30 0.61 0.06 0.23 0.72 PFS/NA T372 0.70 Y (4)
SYRTE-FORb 58789 58814 -0.34 0.30 0.25 0.06 0.23 0.46 0.6 [1] T328 0.34 Y (4)
PTB-CSF1 58784 58814 -0.13 0.07 0.26 0.02 0.07 0.28 PFS/NA T371 0.28 Y (5)
PTB-CSF2 58784 58814 -0.42 0.11 0.17 0.02 0.07 0.21 PFS/NA T370 0.17 Y (5)
SU-CsFO2 58784 58814 -0.11 0.20 0.22 0.10 0.46 0.55 PFS/NA T315 0.50 Y (6)

Notes:
(1) Continuously operating as a clock participating to TAI
(2) Report 29 OCT. 2019 by IT
(3) Report 06 NOV. 2019 by NIM
(4) Report 03 DEC. 2019 by LNE-SYRTE
(5) Report 03 DEC. 2019 by PTB
(6) Report 28 NOV. 2019 by SU
[1] CCTF Recommendation 2 (2017) : Updates to the CIPM list of standard frequencies in Consultative
Committee for Time and Frequency Report of the 21st meeting (2017), 2017, 56 p.
[2] M. Pizzocaro, F. Bregolin, P. Barbieri, B. Rauf, F. Levi and D. Calonico, Absolute frequency measurement of the
1S0