RDV72 (Astrometric/Geodetic VLBA-72) 2008 Dec 17 18:00 Day 352 Notes prepared by David Gordon, NVI/GSFC Schedule name: rdv72.skd On ftp.aoc.nrao.edu (aspen): VLBA Pointing files: rdv72crd.br rdv72crd.fd rdv72crd.hn rdv72crd.kp rdv72crd.la rdv72crd.mk rdv72crd.nl rdv72crd.ov rdv72crd.pt rdv72crd.sc Summary file for correlator: rdv72.sksum Sked file: rdv72.skd Text file: rdv72.txt At IVS Data Center (ftp://cddisa.gsfc.nasa.gov/vlbi/ivsdata/aux/2008/rdv72) Sked file: rdv72.skd Text file: rdv72.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: 1439 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: 48 48 46 23 41 48 48 45 48 48 47 48 47 38 42 32 44 % cal. time: 4 4 4 2 4 4 4 4 4 3 4 4 4 4 4 4 4 % slew time: 27 28 26 30 21 27 27 27 26 17 27 27 28 18 11 48 26 % idle time: 20 19 23 43 33 19 20 23 21 30 21 19 20 39 42 15 26 total # scans: 347 381 369 209 338 379 375 354 374 298 367 377 375 367 343 343 349 # scans/hour : 14 16 15 9 14 16 16 15 16 12 15 16 16 15 14 14 15 Avg scan (sec): 119 109 107 96 106 109 111 110 111 139 109 110 108 90 106 81 107 # 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: 934 954 911 474 827 951 949 895 946 909 921 949 933 793 840 685 867 Total GB(M5): 830 848 809 422 735 845 843 795 841 808 819 843 829 705 747 608 771 # OF OBSERVATIONS BY BASELINE | Br Fd Hn Ho Kk Kp La Mk Nl Ny Ov Pt Sc Ts Wz Zc StnTotal ------------------------------------------------------------------------------------------ Br| 280 253 40 167 290 284 212 276 104 298 284 242 94 83 61 2968 Fd| 308 43 154 350 363 205 343 96 304 365 321 75 99 65 3371 Hn| 20 120 281 304 162 328 119 255 303 329 63 127 80 3052 Ho| 72 46 44 71 36 4 47 44 29 136 8 22 662 Kk| 168 153 287 138 47 185 155 123 133 28 20 1950 Kp| 348 219 320 86 332 351 294 75 83 54 3297 La| 204 343 102 307 372 315 77 101 70 3387 Mk| 187 52 239 206 166 112 28 24 2374 Nl| 109 285 342 327 72 108 71 3285 Ny| 78 101 103 107 176 181 1465 Ov| 310 258 86 68 47 3099 Pt| 314 76 100 69 3392 Sc| 56 126 78 3081 Ts| 56 90 1308 Wz| 249 1440 Zc| 1181 Number of 2-station scans: 484 Number of 3-station scans: 167 Number of 4-station scans: 55 Number of 5-station scans: 24 Number of 6-station scans: 22 Number of 7-station scans: 31 Number of 8-station scans: 33 Number of 9-station scans: 54 Number of 10-station scans: 63 Number of 11-station scans: 87 Number of 12-station scans: 40 Number of 13-station scans: 23 Number of 14-station scans: 8 Number of 15-station scans: 14 Number of 16-station scans: 0 Total # of scans, observations: 1105 19656 There are several 'fringe finder' scans at the start and near the end. First 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 1342+662 08352-180030| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 1354-152 08352-180846| 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 1342+662 08352-195105| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| Last fringe finder scan: name yyddd-hhmmss Br Fd Hn Ho Kk Kp La Mk Nl Ny Ov Pt Sc Ts Wz Zc 1342+662 08353-175431| 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 two initial long (5 min) scans, for use in fringe finding. All stations except Hobart are in the first scan, and Hobart and 10 other stations 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 is one long (5-min) scan near the end, for use in fringe finding if needed. - 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 sixth 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 at GSFC using sked. SOURCE SELECTION There are a total of 93 sources scheduled in this session. Among them, 30 sources are from the astrometric monitoring list and 50 are from the geodetic catalog list. There are also the following 13 requested sources: 2359-221 00 02 12.023 -21 53 09.91 2000.0 0.0 Phillips 0000-160 00 03 27.347 -15 47 05.43 2000.0 0.0 Phillips 0112-245 01 14 57.348 -24 19 44.93 2000.0 0.0 Kovalev 0206-178 02 08 35.007 -17 39 34.85 2000.0 0.0 Kovalev 0315-282 03 17 33.704 -28 03 18.29 2000.0 0.0 Phillips 0527-253 05 29 57.055 -25 15 58.64 2000.0 0.0 Phillips 0540-270 05 42 12.661 -26 58 43.10 2000.0 0.0 Phillips 0609-284 06 11 51.300 -28 28 00.16 2000.0 0.0 Phillips 0937-282 09 40 04.963 -28 29 29.66 2000.0 0.0 Phillips 1501-343 15 05 02.36 -34 32 57.2 2000.0 0.0 Kovalev 1528-274 15 31 24.126 -27 35 31.58 2000.0 0.0 Kovalev 1856-252 18 59 04.996 -25 09 47.23 2000.0 0.0 Phillips 2350-280 23 53 11.368 -27 43 24.80 2000.0 0.0 Phillips 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 Kokee Chan Sky Tracks LO IF BBC | LO IF BBC # 1 X 8405.99 2, 4, 6, 8 7900 B 505.99| 7600 A 805.99 3 2 X 8475.99 10,12,14,16 7900 B 575.99| 7600 A 875.99 4 3 X 8790.99 18,20,22,24 7900 B 890.99| 8100 C 690.99 5 4 X 8895.99 26,28,30,32 7900 B 995.99| 8100 C 795.99 6 5 S 2232.99 3, 5, 7, 9 2900 A 667.01| 1500 B 732.99 9 6 S 2262.99 11,13,15,17 2900 A 637.01| 1500 B 762.99 10 7 S 2352.99 19,21,23,25 2900 A 547.01| 1500 B 852.99 13 8 S 2372.99 27,29,31,33 2900 A 527.01| 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: dec08 directory on aspen: /astronomy/dec08/rdv72 or /home/archive/e2e/archive/operations/VLBA/observe/dec08/rdv72 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.