RDV71 (Astrometric/Geodetic VLBA-71) 2008 Sept 3 18:00 Day 247 Notes prepared by David Gordon, NVI/GSFC Schedule name: rdv71.skd On ftp.aoc.nrao.edu (aspen): VLBA Pointing files: rdv71crd.br rdv71crd.fd rdv71crd.hn rdv71crd.kp rdv71crd.la rdv71crd.mk rdv71crd.nl rdv71crd.ov rdv71crd.pt rdv71crd.sc Summary file for correlator: rdv71.sksum Sked file: rdv71.skd Text file: rdv71.txt At IVS Data Center (ftp://cddisa.gsfc.nasa.gov/vlbi/ivsdata/aux/2008/rdv71) Sked file: rdv71.skd Text file: rdv71.txt This experiment uses the 10 VLBA stations and 6 IVS stations. SUBNET Br-Fd-Hn-Ho-Kk-Kp-La-Mk-Nl-Ny-Ov-Pt-Sc-Ts-Wz-Zc Total time: 1440 minutes ( 24.0 hours). Key: Br=BR-VLBA Fd=FD-VLBA Hn=HN-VLBA Ho=HOBART26 Kk=KOKEE Kp=KP-VLBA La=LA-VLBA Mk=MK-VLBA Nl=NL-VLBA Ny=NYALES20 Ov=OV-VLBA Pt=PIETOWN Sc=SC-VLBA Ts=TSUKUB32 Wz=WETTZELL Zc=ZELENCHK Br Fd Hn Ho Kk Kp La Mk Nl Ny Ov Pt Sc Ts Wz Zc Avg % obs. time: 37 36 37 19 37 36 36 34 36 45 35 36 35 40 40 33 36 % cal. time: 5 5 5 3 5 5 5 5 5 4 5 5 5 5 4 4 5 % slew time: 33 33 32 31 24 34 32 35 32 20 33 33 33 22 12 51 31 % idle time: 25 25 26 46 33 24 26 24 26 30 26 25 26 32 42 10 28 total # scans: 424 427 414 217 409 431 429 437 421 350 434 430 407 415 365 367 398 # scans/hour : 18 18 17 9 17 18 18 18 18 15 18 18 17 17 15 15 17 Avg scan (sec): 75 73 77 77 77 73 72 67 73 111 70 72 75 84 95 78 77 # data tracks: 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 # Mk5 tracks: 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 Total GBytes: 800 788 799 420 790 798 789 765 780 888 778 789 766 850 821 713 771 Total GB(M5): 711 700 710 373 702 709 701 680 693 789 691 701 681 755 729 634 685 Total number of tapes: 1.1 Total GBytes (M5) recorded: 10961.0 # OF OBSERVATIONS BY BASELINE | Br Fd Hn Ho Kk Kp La Mk Nl Ny Ov Pt Sc Ts Wz Zc StnTotal ------------------------------------------------------------------------------------------ Br| 322 304 19 216 335 340 254 328 168 353 342 273 117 145 117 3633 Fd| 337 20 196 388 400 234 372 150 337 402 341 96 151 113 3859 Hn| 10 163 322 352 192 365 179 290 346 358 92 183 133 3626 Ho| 55 22 20 52 15 5 23 20 9 148 5 17 440 Kk| 208 196 371 181 78 232 197 155 151 65 48 2512 Kp| 388 247 357 139 371 398 310 100 136 99 3820 La| 233 389 156 347 420 337 103 157 118 3956 Mk| 217 87 277 235 183 146 63 50 2841 Nl| 163 329 382 350 101 166 125 3840 Ny| 128 154 152 137 238 222 2156 Ov| 354 277 114 118 86 3636 Pt| 333 101 154 116 3954 Sc| 71 171 128 3448 Ts| 82 106 1665 Wz| 274 2108 Zc| 1752 First three fringe finder scans: Source Start DURATIONS name yyddd-hhmmss Br Fd Hn Ho Kk Kp La Mk Nl Ny Ov Pt Sc Ts Wz Zc 1803+784 08247-180000| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 0919-260 08247-180741| 300 300 300 300 300 300 300 300 300 300 300 | 1357+769 08247-181454| 300 300 300 300 300 300 300 300 300 300 300 300 300| Fringe finder after Intensive break: name yyddd-hhmmss Br Fd Hn Ho Kk Kp La Mk Nl Ny Ov Pt Sc Ts Wz Zc 0954+658 08247-194627| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| Last two fringe finder scans: name yyddd-hhmmss Br Fd Hn Ho Kk Kp La Mk Nl Ny Ov Pt Sc Ts Wz Zc 0919-260 08248-174333| 300 300 300 300 300 300 300 300 300 300 300 300 | 1803+784 08248-175418| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| Special Notes for this session: - In this RDV ALL stations will record on Mark5A. - The synch time for the VLBA correlator using Mark5 is ~25 seconds. Because of this, stations will start taking data 25 seconds prior to the normal scan time. They will continue to take data between scans if there is a gap of less than 25 seconds. - There are three initial long (5 min) scans, for use in fringe finding. All stations except Hobart are in the first scan, and Hobart and 10 other sataions are in the second scan. An additional long (5 min) scan is placed right after the Intensive break, for use as a fringe finder if needed. Finally, there are two long (5-min) scans near the end, also for use in fringe finding if needed. Hobart participates in the first of these, but not the second (last) scan. - Wettzell and Kokee are absent from 18:15 to 19:45 because of the UT1 intensive VLBI experiment. - The fluxes use our most recent models. Purpose ======= This is the fifth of six bi-monthly coordinated astrometric/geodetic experiments in 2008 that use the full 10-station VLBA plus up to 10 geodetic stations capable of recording VLBA modes. This year's series is a continuation of the highly successful RDV series begun in 1997. These experiments are being coordinated by the geodetic VLBI programs of three agencies: USNO, NASA, and NRAO. The experiments have been designed so that the same data set may be used by each agency for its particular goals. USNO and Bordeaux Observatory will perform repeated imaging and correction for source structure. These sources will establish a set of core reference sources with known structure and precisely known positions. These data will provide the basis for evaluating the long term stability of the radio reference frame and the ultimate accuracy of wide angle astrometric measurements of extragalactic radio sources using VLBI. NASA will analyze this data to determine a high accuracy terrestrial reference frame. The data will incorporate the VLBA stations into the VLBI reference frame through the inclusion of other geodetic stations for which we have long histories. The data will also produce the most accurate Earth rotation results ever produced. We will use these data to make accurate absolute measurements of UT1. NRAO will use these sessions to provide a service to users who require high quality positions for a small number of sources. While the quality of these results will be high, the observing and data reduction overhead required will be minimal because such sources can be incorporated into a session of the regular geodetic observations, instead of requiring special observations. Sources for this series of experiments will be selected using the proposed approach. For each experiment we will select a set of 70-80 sources out of the pool of 394 Northern Hemisphere ICRF sources. About 40-50 of these will remain the same from experiment to experiment and will be chosen to optimize the goals of the three groups. Schedule ======== This is a new schedule generated by David Gordon using sked. SOURCE SELECTION There are a total of 85 sources in this session. Among them, 30 sources are from the astrometric monitoring list and 55 are from the geodetic catalog list. SCHEDULING ALGORITHMS This schedule uses the "SRCEVN SQRT" mode of Sked. In the absense of any constraints, Sked will preferentially observe strong sources that have high visibility. This mode attempts to smooth out the number of observations per source. Recording Mode and Frequencies: same as previous experiments ============================================================ The data will be recorded using the following setup: 8 channels 1:4 fan-out 16 MHz sample rate 1-bit sampling This recording mode is designated 128-8-1. The correlator speed-up factor is 2. The frequency sequence covers 490 MHz at X-band and 140 MHz at S-band using 4 channels in each band. This span fits in one VLBA receiver passband but it uses both the high and low parts of the geodetic receivers. Because only 8 channels total are available when observing with the VLBA stations, a wider spanned bandwidth is not advisable. These tables list the setup for the VLBA stations, the geodetic stations with VLBA back ends, and the geodetic stations with Mark IV back ends. These are the SAME frequencies used in all the standard RDV sessions. Geodetic stations: please read the special procedures in the next section! VLBA Fairbanks Kokee Chan Sky Tracks LO IF BBC | LO IF BBC #| LO IF BBC # 1 X 8405.99 2, 4, 6, 8 7900 B 505.99| 7600.1 A 805.89 3|7600 A 805.99 3 2 X 8475.99 10,12,14,16 7900 B 575.99| 7600.1 A 875.89 4|7600 A 875.99 4 3 X 8790.99 18,20,22,24 7900 B 890.99| 8080.0 C 710.99 5|8100 C 690.99 5 4 X 8895.99 26,28,30,32 7900 B 995.99| 8080.0 C 815.99 6|8100 C 795.99 6 5 S 2232.99 3, 5, 7, 9 2900 A 667.01| 1540.1 B 692.89 9|1500 B 732.99 9 6 S 2262.99 11,13,15,17 2900 A 637.01| 1540.1 B 722.89 10|1500 B 762.99 10 7 S 2352.99 19,21,23,25 2900 A 547.01| 1540.1 B 812.89 13|1500 B 852.99 13 8 S 2372.99 27,29,31,33 2900 A 527.01| 1540.1 B 832.89 14|1500 B 872.99 14 VLBA | Tsukuba Chan Sky Tracks LO IF BBC | LO IF BBC # 1 X 8405.99 2, 4, 6, 8 7900 B 505.99| 7680 A 725.99 3 2 X 8475.99 10,12,14,16 7900 B 575.99| 7680 A 795.99 4 3 X 8790.99 18,20,22,24 7900 B 890.99| 8080 A 710.99 5 4 X 8895.99 26,28,30,32 7900 B 995.99| 8080 A 815.99 6 5 S 2232.99 3, 5, 7, 9 2900 A 667.01| 1600 B 632.99 9 6 S 2262.99 11,13,15,17 2900 A 637.01| 1600 B 662.99 10 7 S 2352.99 19,21,23,25 2900 A 547.01| 1600 B 752.99 13 8 S 2372.99 27,29,31,33 2900 A 527.01| 1600 B 772.99 14 Medicina, Wettzell, Matera, GGAO, TIGO VLBA | Westford, NOTO, HartRAO, Onsala Chan Sky Tracks LO IF BBC | LO IF VC VC# Patch 1 X 8405.99 2, 4, 6, 8 7900 B 505.99| 8080.0 1 325.99 3 H 2 X 8475.99 10,12,14,16 7900 B 575.99| 8080.0 1 395.99 4 H 3 X 8790.99 18,20,22,24 7900 B 890.99| 8580.1 3 210.89 5 L 4 X 8895.99 26,28,30,32 7900 B 995.99| 8580.1 3 315.89 6 H 5 S 2232.99 3, 5, 7, 9 2900 A 667.01| 2020.0 2 212.99 9 H 6 S 2262.99 11,13,15,17 2900 A 637.01| 2020.0 2 242.99 10 H 7 S 2352.99 19,21,23,25 2900 A 547.01| 2020.0 2 332.99 13 H 8 S 2372.99 27,29,31,33 2900 A 527.01| 2020.0 2 352.99 14 H Special procedures for non-VLBA stations ======================================== SEE THE NOTE AT THE START ABOUT MARK5 recording. Special procedures for Medicina, Westford, Onsala, Wettzell, Tsukuba, Matera, GGAO, TIGO ================================================================== These stations have Mark IV formatters. If you are using Field System 9.x, use the procedures and snap files generated by DRUDG. The IF3 command in the procedure IFDSX assumes that VC3 will be patched to High. Please verify that the switches for your IF3 module are wired this way, and if they are not please edit the IF3 command to change the switches. If you have questions about the wiring, please contact Brian Corey at Haystack. Special procedures for Kokee ================================================== These stations have VLBA back ends. Use the procedures generated by DRUDG. BBCs 3,4,5,6 are used at X-band with IFs A and C. BBCs 9,10,13,14 are used at S-band with IF B. CHECKLIST for non-VLBA stations =============================== Please follow the checklist below to ensure you have done all the necessary steps for this experiment: 1. Make .prc file with DRUDG and check them out, or use the procedures from last session. Check out parity check procedures. 2. Make the .snp file with DRUDG. 3. Set up your system to monitor the clocks with the "gps-fmout" or "fmout-gps" commands. If you have questions about this, please contact Ed Himwich as soon as possible. 4. Send a "ready" message an hour or so before the experiment to the ivs-ops mail list. Copy analysts@nrao.edu on your ready message. 5. Send a "start" message soon after you have started recording. Copy analysts@nrao.edu on the message. 6. At the end of the experiment, send a "finish" message summarizing how the experiment was conducted. Copy analysts@nrao.edu on your message. 8. Transfer your log files to your normal log file data center. The directories for three possible servers are listed below: ftp cddisa.gsfc.nasa.gov/ivsincoming directory on vlbeer: sep08 directory on aspen: /home/aspen6/astronomy/sep08/rdv71 NOTE: If you don't normally use aspen, you should not put your log file on that server. The VLBA correlator knows where to find your log files. Correlation =========== This experiment will be correlated at the VLBA Correlator. Disks should be shipped to Socorro as soon after the experiment as practical.