IVS-T2008 (International VLBI Service - Terrestical reference frame observations) 2002 Aug 06/07 Notes prepared by Arno Mueskens Geodetic Institute of the University of Bonn, Germany Purpose ======= The purpose of the IVS-T2 sessions is to monitor the TRF via monthly sessions. All geodetic stations participate in at least three T2 sessions each year. These sessions replace the IRIS-S sessions observed in previous years. The TRF determine from single session solutions or from a global solution is very important IVS product because this is an essential part for creating the ITRF by corresponding IERS Product Center. A particular strength of VLBI is its contribution to the scale of the ITRF. Usually the TRF is computed from the 24h sessions that are dedicated to observing the EOP. Network ======= The standard configuration of the monthly observed IVS-T2 experiments consists of eight stations. The eight station differ in some extent between all available IVS geodetic network stations from month to month. Schedule ======== This schedule was generated by SKED using the EUR2-SX band and the EUR2SX-C-4 frequency setup, depending on which station are available for this observation. Variable scan lengths with a minimum 40 sec. and the most recent source flux models are included. SNR goals are 23 at X-band and 20 at S-band for all baselines. The predicted SNRs used include a 30 ps noise contribution added in quadrature, which is a typical magnitude for the reweight constants applied in SOLVE solutions. The schedule is generated for the estimation of all five (nine) earth orientation parameters, clock offsets and clock rates for all participating stations except the reference station and atmo- sphere parameters for all participating stations. It was optimized for three earth orientation parameters (polar motion, UT1). Other optimization features enabled for this experiment : - the covariance analysis during schedule generation considers the previous 2 hours of observations, - minor SKED optimization parameters . maximum number of observations, . minimum time, were optimized over the best ( in a covariance sense ) 75% of the possible observations, this produces a somewhat more even sky distribution, - observations were weighted by their expected SNRs, - 30 ps noise contribution added, - mimimum time between observations of the same radio source was set to 25 min - using 59 source for improving the sky covorage Procedures ========== NO PREPASS TIME: There is no time allowed in the schedule for prepassing tapes. Therefore all tapes needed for this experiment must be pre-checked before the start of this experiment. Please generate the procedures for this session using drudg. THIS SCHEDULE HAS 10 SEC. EARLY TAPE START !! --------------------------------------------- =========================================================== Parameter values for experiment t2008 Experiment description: IVS-T2008 Scheduler: mueskens Correlator: BONN Nominal start: 2002-218-17:30:01 Nominal end: 2002-219-17:30:01 Current yyyyddd: 2002218 (2002.60) ( 12493 MJD, TUES 6AUG.) Greenwich sidereal time: 14:30:20.17 (17:30: 1 UT) Sun's RA and DEC: 9h 6.2m 16d 36.2 =========================================================== First observations Observation listing from file /geo/SKED/sked006/sk_schedules/t2008.skd for experiment t2008 Source Start DURATIONS name yyddd-hhmmss Gc Hh Kk Nt Gg Sh Wf Wz 1357+769 02218-173001| 50 60 60 100 100 70| 0727-115 02218-173404| 170 170 160 | 0528+134 02218-173738| 40 110 110 | 1044+719 02218-174037| 40 40 | 1749+096 02218-174130| 140 40 140 50| End of listing. =========================================================== Last observations Observation listing from file /geo/SKED/sked006/sk_schedules/t2008.skd for experiment t2008 Source Start DURATIONS name yyddd-hhmmss Gc Hh Kk Nt Gg Sh Wf Wz 0804+499 02219-172232| 250 280 240 280 260| End of listing. Observation listing from file /geo/SKED/sked006/sk_schedules/t2008.skd for experiment t2008 Source Start DURATIONS name yyddd-hhmmss Gc Hh Kk Nt Gg Sh Wf Wz 0805+410 02219-171120| 230 230 | 1351-018 02219-171306| 170 170 160| 1334-127 02219-171644| 140 40 140 40| 0106+013 02219-171720| 40 40 40 | 0003-066 02219-171910| 100 100 | 0804+499 02219-172232| 250 280 240 280 260| End of listing. =========================================================== Total time: 1436 minutes ( 23.9 hours). Key: Gc=GILCREEK Hh=HARTRAO Kk=KOKEE Nt=NOTO Gg=ORION_5M Sh=SESHAN25 Wf=WESTFORD Wz=WETTZELL Gc Hh Kk Nt Gg Sh Wf Wz Avg % obs. time: 46 17 50 38 6 19 41 42 32 % cal. time: 5 1 5 5 0 1 3 5 3 % slew time: 23 28 17 36 1 33 13 10 20 % idle time: 24 51 26 19 91 44 41 42 42 # of tapes : 1.3 .5 1.4 1.1 .2 .6 1.1 1.1 total # scans: 466 158 455 433 40 166 304 436 307 # scans/hour : 19 6 19 18 1 6 12 18 12.8 Avg scan (sec): 86 94 95 76 145 103 117 83 99 tape change times (hhmm): 1239 0000 1133 1624 0000 0000 1529 1420 # OF OBSERVATIONS BY BASELINE | Gc Hh Kk Nt Gg Sh Wf Wz StnTotal ---------------------------------------------- Gc|466 3 421 82 20 125 160 112 923 Hh| 158 0 149 0 35 39 122 348 Kk| 455 42 19 114 162 70 828 Nt| 433 7 66 151 403 900 Gg| 40 0 40 10 96 Sh| 166 49 83 472 Wf| 304 165 766 Wz| 436 965 Number of 2-station scans: 455 Number of 3-station scans: 240 Number of 4-station scans: 124 Number of 5-station scans: 40 Number of 6-station scans: 22 Number of 7-station scans: 0 Number of 8-station scans: 0 Total # of scans, observations: 881 2649 =========================================================== Recording mode Name Code EUR2-SX SX Recording mode setup for: GILCREEK Mode Tot.Rate Tot.BandW #chan #bits Barrel VLBA1:2 128.000 Mbits 64.000 MHz 14 1 8:1 Chan.BW #Subpasses Tracks(*fan) Tot.tracks Speed 4.00 MHz 1 16(*2) 32 80.00 X-band spanned bw= 360.0 MHz rms spanned bw= 140.2 MHz S-band spanned bw= 80.0 MHz rms spanned bw= 30.2 MHz Effective number of channels recorded per sub-pass X S Total 10.000 6.000 16.000 Recording mode setup for: HARTRAO NOTO GGAO7108 SESHAN25 WESTFORD WETTZELL Mode Tot.Rate Tot.BandW #chan #bits Barrel Mk341:2 128.000 Mbits 64.000 MHz 14 1 NONE Chan.BW #Subpasses Tracks(*fan) Tot.tracks Speed 4.00 MHz 1 16(*2) 32 80.00 X-band spanned bw= 360.0 MHz rms spanned bw= 140.2 MHz S-band spanned bw= 80.0 MHz rms spanned bw= 30.2 MHz Effective number of channels recorded per sub-pass X S Total 10.000 6.000 16.000 Recording mode setup for: KOKEE Mode Tot.Rate Tot.BandW #chan #bits Barrel VLBA1:2 128.000 Mbits 64.000 MHz 14 1 16:1 Chan.BW #Subpasses Tracks(*fan) Tot.tracks Speed 4.00 MHz 1 16(*2) 32 80.00 X-band spanned bw= 360.0 MHz rms spanned bw= 140.2 MHz S-band spanned bw= 80.0 MHz rms spanned bw= 30.2 MHz Effective number of channels recorded per sub-pass X S Total 10.000 6.000 16.000 =========================================================== Tape types ID Station Tape length Density Gc GILCREEK 17400feet (Thin ) 56700. (High) Hh HARTRAO 17400feet (Thin ) 56250. (High) Kk KOKEE 17400feet (Thin ) 56700. (High) Nt NOTO 17400feet (Thin ) 56250. (High) Gg GGAO7108 17400feet (Thin ) 56250. (High) Sh SESHAN25 17400feet (Thin ) 56250. (High) Wf WESTFORD 17400feet (Thin ) 56250. (High) Wz WETTZELL 17400feet (Thin ) 56250. (High) =========================================================== SNR Targets Minimum SNR by baseline for multi-baseline scans X-band (margin 0) S-band (margin 0) Gc Hh Kk Nt Gg Sh Wf Gc Hh Kk Nt Gg Sh Wf Hh 23 Hh 20 Kk 23 23 Kk 20 20 Nt 23 23 23 Nt 20 20 20 Gg 15 15 15 15 Gg 15 15 15 15 Sh 23 23 23 23 15 Sh 20 20 20 20 15 Wf 23 23 23 23 15 23 Wf 20 20 20 20 15 20 Wz 23 23 23 23 15 23 23 Wz 20 20 20 20 15 20 20