Session Notes for rd2505 Prepared by K. Le Bail, OSO / Chalmers - Onsala, Sweden =========================================================== PURPOSE AND GENERAL NOTES =========================================================== GAIA proposal The session RD2505 will observe a total of 59 optically-bright ICRF3 sources selected from the Gaia Data Release 2 catalog with the following criteria: (i) relatively compact VLBI structure (structure index < 3), (ii) stronger than 0.25 Jy at X and S band, (iii) not observed in any of the IVS sessions during the past 30 days (excluding the intensive sessions), (iv) observed at least 6 times since August 2014 (beginning of the Gaia operations) and with no gap longer than two years. The optical magnitude of the sources ranges from 16.0 to 20.0. The goal is to improve the overall temporal coverage of the observations by IVS of those optically-bright ICRF3 sources during the Gaia operations. During the time, Wettzell (Wz) will observe: INT I25239 from 1800 UT to 1845 UT / DOY 239 INT I25240 from 1715 UT to 1800 UT / DOY 240 The fill command was used for all stations using a fill offset of 10 seconds. NOTE: This is the last of the last (!) session of the GAIA proposal observing program. Thank you to the IVS to allow us to observe these sources for 12 years. =========================================================== ----- Parameter listing -------------------------------------- Experiment: RD2505 Description R&D-08/2025 Scheduler: OSO Correlator: WASH Start: 2025-239-18:00:00 End: 2025-240-18:00:00 Current yyyyddd: 2025239 (2025.65) ( 20915 MJD, WED. 27AUG.) Greenwich sidereal time: 16:24:53 (18:00:00 UT) Sun's RA and DEC: 10h 26.3m 9d 46.8 =========================================================== First observations Observation listing from file ./rd2505.skd for experiment RD2505 Source Start DURATIONS name yyddd-hhmmss Ft Hh On T6 Wz 1633+38 25239-180000| 40 40 40 | 0954+658 25239-180157| 59 59 | 0707+476 25239-180420| 122 122 | 1313-333 25239-180456| 40 40 | 1511-100 25239-180750| 68 110 110 | 1319-093 25239-181202| 141 163 163 | 1443-162 25239-181647| 639 711 711 | End of listing. =========================================================== Last observations Observation listing from file ./rd2505.skd for experiment RD2505 Source Start DURATIONS name yyddd-hhmmss Ft Hh On T6 Wz 1951+355 25240-173456| 654 715 76 | 1637+574 25240-173810| 71 60 | 1221+809 25240-174037| 96 70 | 1739+522 25240-174332| 489 105 | 2150+173 25240-174805| 204 204 245 | 0954+658 25240-175321| 40 124 | 2244-372 25240-175458| 302 302 | 1147+245 25240-175628| 212 212 | End of listing. =========================================================== SKED Summary from file ./rd2505.skd for experiment RD2505 (all scans with at least one subnet station) Average number of obs. per baseline per source(normalized by up-time) = 10.4 Min = 0.0 Max = 144.0 (Baseline Ft-T6 on 1511-100) RMS = 12.3 Total time: 1440 minutes ( 24.0 hours). Key: Ft=FORTLEZA Hh=HARTRAO On=ONSALA60 T6=TIANMA65 Wz=WETTZELL Ft Hh On T6 Wz Avg % obs. time: 48 45 76 42 70 56 % cal. time: 1 2 2 3 3 2 % slew time: 14 30 12 37 7 20 % idle time: 36 22 9 18 20 21 total # scans: 121 159 196 216 246 187 # scans/hour : 5 7 8 9 10 8 Avg scan (sec): 339 244 333 167 245 265 # data tracks: 32 32 32 32 32 # Mk5 tracks: 32 32 32 32 32 Total TB(M5): 5.26 4.97 8.37 4.63 7.71 6.19 # OF OBSERVATIONS BY BASELINE | Ft Hh On T6 Wz Total ----------------------------------- Ft| 61 86 61 94 302 Hh| 105 108 127 401 On| 148 177 516 T6| 194 511 Wz| 592 Number of 2-station scans: 66 Number of 3-station scans: 111 Number of 4-station scans: 92 Number of 5-station scans: 21 Total number of scans: 290 Total number of obs: 1161 Total integrated obs-time: 271874 Average obs-time: 234.2 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: | 163| 188| 126| 138| 123| 63| 50| 43| 37| 28| 26| 9| 16| 8| 13| 3| 12| 15| 22| 78| Average X-band SNRs by baseline | Ft Hh On T6 Wz AVG ---------------------------------- Ft| 41 38 137 57 65 Hh| 42 251 75 109 On| 189 101 104 T6| 329 249 Wz| 163 Average S-band SNRs by baseline | Ft Hh On T6 Wz AVG ---------------------------------- Ft| 22 19 80 25 34 Hh| 24 123 37 54 On| 92 41 49 T6| 136 114 Wz| 69 =========================================================== Recording mode Name Code AOVSX16W SX Recording mode for: FORTLEZA Mode Tot.Rate #Chan Chan.BW Tot.BW #BBC #bits Tracks*(fan) Tot.tracks Barrel Mk341:2 1024 Mbps 16 16 Mhz 256 Mhz 14 2 32*(2) 64 NONE X-band spanned bw= 720.0 MHz rms spanned bw= 275.0 MHz S-band spanned bw= 88.0 MHz rms spanned bw= 30.9 MHz Effective number of 1-bit channels recorded per sub-pass X S Total 19.13 11.48 30.61 Recording mode for: HARTRAO ONSALA60 TIANMA65 WETTZELL Mode Tot.Rate #Chan Chan.BW Tot.BW #BBC #bits Tracks*(fan) Tot.tracks Barrel Mk341:1 1024 Mbps 16 16 Mhz 256 Mhz 14 2 32*(1) 32 NONE X-band spanned bw= 720.0 MHz rms spanned bw= 275.0 MHz S-band spanned bw= 88.0 MHz rms spanned bw= 30.9 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 Speed Ft FORTLEZA Mark5A Hh HARTRAO 17640feet (Thin ) 56250 (HIGH ) 1 On ONSALA60 17640feet (Thin ) 56250 (HIGH ) 1 T6 TIANMA65 17640feet (Thin ) 56250 (HIGH ) 1 Wz WETTZELL 17640feet (Thin ) 56250 (HIGH ) 1 =========================================================== 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) Ft Hh On T6 Ft Hh On T6 Hh 20 Hh 15 On 20 20 On 15 15 T6 20 20 20 T6 15 15 15 Wz 20 20 20 20 Wz 15 15 15 15 ===========================================================