Session Notes for rd1804 Prepared by K. Le Bail, NVI, Inc./GSFC =========================================================== PURPOSE AND GENERAL NOTES =========================================================== GAIA proposal The Laboratory d'Astrophysique de Bordeaux (LAB) subnmitted in 2012 a proposal to observe 195 ICRF2 transfer sources in the context of the GAIA mission. These sources were added to the GSFC monitoring program and 37 sources were scheduled in Gaia-dedicated R&D sessions. In February 2017, we studied the position uncertainties and the observation frequency of the 195 sources of the LAB proposal. Twenty-seven of these sources have a bad observation frequency: they were observed successfully in less than five sessions a year while the LAB requirement was twelve sessions a year. Most of these sources have bad uncertainties compared to the other sources of the set (larger than 50 microas). Three additional sources have good position uncertainties and an observation frequency of five to eleven successful sessions a year. However they are sources that were observed in previous Gaia-dedicated R&D sessions and the concern is that if they are not scheduled in coming dedicated R&D sessions, their observation frequency may drop. The sources scheduled in the Gaia-dedicated R&D sessions scheduled to observe after March 1st, 2017 are these thirty sources. When compared to the previous categories determined by the LAB, one source was in category 1, five sources were in category 2, five sources were in category 3 and nineteen sources were in category 4. In RD1804, we schedule 23 out of the thirty sources in the astro mode of sked. We used a maxscan value of 720 seconds. Forty of the good geodetic sources are used as base of a stable source set and uniform sky coverage. We use the sked flux catalog for all sources. Wettzell and Kokee will observe INT I18118 during the time from 1815 UT to 1945 UT. =========================================================== ----- Parameter listing -------------------------------------- Experiment: RD1804 Description R&D-06/2018 Scheduler: NASA Correlator: HAYS Start: 2018-178-18:00:00 End: 2018-179-18:00:00 Current yyyyddd: 2018178 (2018.49) ( 18297 MJD, WED. 27JUN.) Greenwich sidereal time: 12:23:11 (18:00:00 UT) Sun's RA and DEC: 6h 26.3m 23d 17.9 =========================================================== First observations Observation listing from file ./rd1804.skd for experiment RD1804 Source Start DURATIONS name yyddd-hhmmss Hh Ho Kk Ny Sh Wz 1749+096 18178-180000| 562 562 140 67 152| 2000+472 18178-180315| 79 70 40 79| 0059+581 18178-180531| 60 49 40 60| 0716+714 18178-180726| 95 40 40 95| 1330+476 18178-181022| 243 243| 2329-415 18178-181224| 160 169 169 | 1123+264 18178-181508| 40 40 | 2155-304 18178-181625| 110 110 | 1306+360 18178-181752| 178 178 | 2314-409 18178-181931| 281 281 | End of listing. =========================================================== Last observations Observation listing from file ./rd1804.skd for experiment RD1804 Source Start DURATIONS name yyddd-hhmmss Hh Ho Kk Ny Sh Wz 1349-439 18179-173141| 613 613 | 0241+622 18179-173700| 168 168| IIIZW2 18179-174117| 720 720 | 1251-197 18179-174401| 434 434| 1929+226 18179-175209| 157 100 157| 1803+784 18179-175537| 55 40 40 55| NRAO512 18179-175740| 130 130 | 0642+449 18179-175743| 40 40 40| 0748+126 18179-175901| 40 40| End of listing. =========================================================== SKED Summary from file ./rd1804.skd for experiment RD1804 (all scans with at least one subnet station) Average number of obs. per baseline per source(normalized by up-time) = 4.0 Min = 0.0 Max = 31.5 (Baseline Hh-Wz on 2155-304) RMS = 6.6 Total time: 1440 minutes ( 24.0 hours). Key: Hh=HARTRAO Ho=HOBART26 Kk=KOKEE Ny=NYALES20 Sh=SESHAN25 Wz=WETTZELL Hh Ho Kk Ny Sh Wz Avg % obs. time: 51 62 56 72 69 69 63 % cal. time: 2 2 2 2 2 2 2 % slew time: 28 21 9 10 18 7 16 % idle time: 18 15 33 15 10 21 19 total # scans: 137 143 135 186 157 188 157 # scans/hour : 6 6 6 8 7 8 7 Avg scan (sec): 324 373 356 335 380 318 347 # data tracks: 32 32 32 32 32 32 # Mk5 tracks: 32 32 32 32 32 32 Total TB(M5): 2.84 3.41 3.08 3.98 3.82 3.82 3.49 # OF OBSERVATIONS BY BASELINE | Hh Ho Kk Ny Sh Wz Total ---------------------------------------- Hh| 68 0 43 39 62 212 Ho| 55 14 74 9 220 Kk| 66 81 53 255 Ny| 64 155 342 Sh| 57 315 Wz| 336 Number of 2-station scans: 190 Number of 3-station scans: 136 Number of 4-station scans: 37 Number of 5-station scans: 2 Number of 6-station scans: 0 Total number of scans: 365 Total number of obs: 840 Total integrated obs-time: 277714 Average obs-time: 330.6 Histogram of observation durations Dur: 35 70 105 140 175 210 245 280 315 350 385 420 455 490 525 560 595 630 665 700 735 #Obs: | 175| 23| 41| 66| 29| 26| 43| 42| 40| 24| 16| 27| 38| 24| 47| 29| 18| 15| 21| 96| Average X-band SNRs by baseline | Hh Ho Kk Ny Sh Wz AVG --------------------------------------- Hh| 33 - 32 44 41 37 Ho| 32 39 46 45 38 Kk| 41 42 53 42 Ny| 59 67 55 Sh| 83 54 Wz| 62 Average S-band SNRs by baseline | Hh Ho Kk Ny Sh Wz AVG --------------------------------------- Hh| 25 - 20 21 24 23 Ho| 29 19 22 18 24 Kk| 30 29 33 30 Ny| 22 25 24 Sh| 26 24 Wz| 26 =========================================================== Recording mode Name Code GEOSX8N 8F Recording mode for: HARTRAO HOBART26 KOKEE NYALES20 SESHAN25 WETTZELL Mode Tot.Rate Tot.BandW #BBC #bits Barrel Mk341:1 512 Mbits 128 MHz 14 2 NONE Chan.BW #Subpasses Tracks(*fan) Tot.tracks 8.00 MHz 1 32(*1) 32 X-band spanned bw= 720.0 MHz rms spanned bw= 280.4 MHz S-band spanned bw= 140.0 MHz rms spanned bw= 50.9 MHz Effective number of 1-bit channels recorded per sub-pass X S Total 19.13 11.48 30.61 =========================================================== Tape types ID Station Tape length Density Passes Hh HARTRAO Mark5B Ho HOBART26 Mark5B Kk KOKEE Mark5B Ny NYALES20 Mark5B Sh SESHAN25 Mark5B Wz WETTZELL Mark5B =========================================================== SNR targets Minimum SNR by baseline for multi-baseline scans X-band (margin 0) S-band (margin 0) X-band (ast_margin 0) S-band (ast_margin 0) Hh Ho Kk Ny Sh Hh Ho Kk Ny Sh Ho 20 Ho 15 Kk 20 20 Kk 15 15 Ny 20 20 20 Ny 15 15 15 Sh 20 20 20 20 Sh 15 15 15 15 Wz 20 20 20 20 20 Wz 15 15 15 15 15 ===========================================================