Session Notes for rd2501 Prepared by K. Le Bail, OSO / Chalmers - Onsala, Sweden =========================================================== PURPOSE AND GENERAL NOTES =========================================================== GAIA proposal The session RD2501 will observe a total of 57 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 I25030 from 1715 UT to 1800 UT / DOY 030 The fill command was used for all stations using a fill offset of 10 seconds. Fortleza (Ft) in tagalong mode. =========================================================== ----- Parameter listing -------------------------------------- Experiment: RD2501 Description R&D-01/2025 Scheduler: OSO Correlator: WASH Start: 2025-029-18:00:00 End: 2025-030-18:00:00 Current yyyyddd: 2025029 (2025.08) ( 20705 MJD, WED. 29JAN.) Greenwich sidereal time: 02:36:56 (18:00:00 UT) Sun's RA and DEC: 20h 50.1m -17d 42.9 =========================================================== First observations Observation listing from file ./rd2501.skd for experiment RD2501 Source Start DURATIONS name yyddd-hhmmss Hh On Wz Ft 0116-219 25029-180000| 40 160 160 68| 0507+179 25029-180404| 40 134 134 | 0754+100 25029-180728| 40 90 90 | 0834+250 25029-180950| 201 201 201 | End of listing. =========================================================== Last observations Observation listing from file ./rd2501.skd for experiment RD2501 Source Start DURATIONS name yyddd-hhmmss Hh On Wz Ft 0116-219 25030-173434| 40 259 66| 0745+241 25030-174016| 66 166 | 0506+056 25030-174405| 49 172 | 0834+250 25030-174804| 203 257 | 0722+145 25030-175315| 103 205 | NRAO190 25030-175743| 137 137 | End of listing. =========================================================== SKED Summary from file ./rd2501.skd for experiment RD2501 (all scans with at least one subnet station) Average number of obs. per baseline per source(normalized by up-time) = 6.3 Min = 0.0 Max = 34.3 (Baseline Hh-Wz on 1313-333) RMS = 7.4 Total time: 1440 minutes ( 24.0 hours). Key: Hh=HARTRAO On=ONSALA60 Wz=WETTZELL Ft=FORTLEZA Hh On Wz Ft Avg % obs. time: 40 65 65 1 43 % cal. time: 2 4 4 0 3 % slew time: 38 20 9 1 17 % idle time: 20 10 21 96 37 total # scans: 197 329 335 21 220 # scans/hour : 8 14 14 1 9 Avg scan (sec): 174 171 168 50 140 # data tracks: 32 32 32 32 # Mk5 tracks: 32 32 32 32 Total TB(M5): 4.38 7.22 7.21 0.13 4.73 # OF OBSERVATIONS BY BASELINE | Hh On Wz Ft Total ------------------------------ Hh| 181 187 15 383 On| 319 17 517 Wz| 20 526 Ft| 52 Number of 2-station scans: 163 Number of 3-station scans: 172 Number of 4-station scans: 10 Total number of scans: 345 Total number of obs: 739 Total integrated obs-time: 122525 Average obs-time: 165.8 Histogram of observation durations Dur: 25 50 75 100 125 150 175 200 225 250 275 300 325 350 375 400 425 450 475 500 #Obs: | 268| 75| 47| 36| 35| 22| 30| 35| 15| 13| 11| 11| 7| 16| 6| 2| 4| 13| 93| Average X-band SNRs by baseline | Hh On Wz Ft AVG ----------------------------- Hh| 39 69 34 53 On| 104 37 79 Wz| 57 90 Ft| 44 Average S-band SNRs by baseline | Hh On Wz Ft AVG ----------------------------- Hh| 19 30 21 24 On| 35 17 29 Wz| 25 33 Ft| 21 =========================================================== 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 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 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) Hh On Wz Hh On Wz On 20 On 15 Wz 20 20 Wz 15 15 Ft 20 20 20 Ft 15 15 15 ===========================================================