RDV78 (Astrometric/Geodetic VLBA-78) 2009 December 2 18:00 Day 336 Notes prepared by David Gordon, John Gipson, and Ed Himwich, NVI/GSFC Special notes for this experiment ================================= This session will use 2-bit sampling again, as in the previous RDV. The frequencies and channel bandwidths (8 MHz) are the same as in previous RDV's. The bit rate will be 256 Mbits/sec. The 8 MHz, 2-bit sampling is preferable to 16 MHz, 1-bit sampling because the 16 MHz filters are not very good at the non-VLBA stations. The data will be correlated at the VLBA using the DiFX software correlator. The non-VLBA stations with Mark IV and VLBA4 racks (Kashima, Kokee, Ny Alesund, Wettzell, and Zelenchenskya) should see the "Special operations notes for non-VLBA stations" section below for special instructions. There are 15 full network scans that can be used for 'fringe finding' at the correlator, located at the start, right after the Intensive break, in the middle, and at the end. These scans are: Source Start DURATIONS (seconds) name yyddd-hhmmss Br Fd Hn Kb Kk Kp La Mk Nl Ny Ov Pt Sc Wz Zc 1053+704 09336-180000| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 0014+813 09336-180646| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 2021+614 09336-194546| 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200| 1745+624 09336-232110| 252 330 337 480 480 336 296 480 264 480 311 313 480 480 440| 0059+581 09337-014252| 40 40 40 40 103 40 40 71 40 40 40 40 40 103 60| 0014+813 09337-025956| 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100| 0014+813 09337-090826| 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100| 0602+673 09337-094026| 71 138 72 160 211 130 110 139 81 147 106 118 160 211 165| 1053+704 09337-115913| 84 88 84 87 157 88 86 102 84 209 86 86 95 209 109| 0014+813 09337-153755| 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100| 1053+704 09337-154518| 83 90 89 87 154 89 88 93 87 176 86 88 109 176 109| 1745+624 09337-155224| 278 322 311 395 480 338 297 480 266 480 328 315 480 480 480| 3C309.1 09337-162242| 81 83 82 88 158 83 81 93 82 158 83 83 95 134 76| 1300+580 09337-162556| 414 466 403 480 480 468 447 480 414 480 452 454 480 480 480| 0014+813 09337-175735| 140 140 140 140 140 140 140 140 140 140 140 140 140 140 140| Additional Notes: - Two-bit sampling is used. - In this RDV, all stations will record on Mark5A, except Kashima. The Kashima data is later transferred to Mark5A. - The synch time for the VLBA correlator using Mark5 is ~25 seconds. Because of this, stations will start taking data 30 seconds prior to the normal scan time. They will continue to take data between scans if there is a gap of less than 30 seconds. - 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 2009 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 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 a small number of 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 from the pool of geodetic, astrometric, and monitoring 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. A small number of poorly observed and/or new requested sources may also be included to obtain or improve their positions. Schedule information ==================== This is a new schedule generated by David Gordon at GSFC using sked. Schedule file name: rdv78.skd On ftp.aoc.nrao.edu (aspen): VLBA Pointing files: rdv78crd.br rdv78crd.fd rdv78crd.hn rdv78crd.kp rdv78crd.la rdv78crd.mk rdv78crd.nl rdv78crd.ov rdv78crd.pt rdv78crd.sc Summary file for correlator: rdv78.sksum Sked file: rdv78.skd Text file: rdv78.txt Vex file: rdv78.vex At IVS Data Center (ftp://cddisa.gsfc.nasa.gov/vlbi/ivsdata/aux/2009/rdv78) Sked file: rdv78.skd Text file: rdv78.txt This experiment uses the 10 VLBA stations and 5 IVS stations. The IVS stations are: KASHIM34, KOKEE, NYALES20, WETTZELL, and ZELENCHK. Total time: 1440 minutes ( 24.0 hours). Key: Br=BR-VLBA Fd=FD-VLBA Hn=HN-VLBA Kb=KASHIM34 Kk=KOKEE Kp=KP-VLBA La=LA-VLBA Mk=MK-VLBA Nl=NL-VLBA Ny=NYALES20 Ov=OV-VLBA Pt=PIETOWN Sc=SC-VLBA Wz=WETTZELL Zc=ZELENCHK Br Fd Hn Kb Kk Kp La Mk Nl Ny Ov Pt Sc Wz Zc Avg % obs. time: 38 45 36 30 36 45 44 39 40 42 43 45 43 39 29 40 % cal. time: 4 4 4 4 4 4 4 5 4 4 4 4 4 4 4 4 % slew time: 28 25 26 37 22 26 25 30 25 20 27 25 27 12 49 27 % idle time: 29 25 32 28 37 23 26 25 29 33 24 25 25 45 18 29 total # scans: 370 367 371 339 367 370 368 398 371 343 367 368 359 327 337 361 # scans/hour : 15 15 15 14 15 15 15 17 15 14 15 15 15 14 14 15 Avg scan (sec): 88 105 85 77 84 106 104 86 94 107 102 105 103 102 74 94 # data tracks: 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 # Mk5 tracks: 16 16 16 16 16 16 16 16 16 16 16 16 16 16 16 Total GBytes: 1577 1786 1535 1311 1501 1806 1774 1657 1659 1686 1741 1789 1725 1554 1257 1624 Total GB(M5): 1402 1587 1364 1165 1334 1605 1577 1473 1475 1499 1547 1590 1533 1381 1117 1443 # OF OBSERVATIONS BY BASELINE | Br Fd Hn Kb Kk Kp La Mk Nl Ny Ov Pt Sc Wz Zc StnTotal ------------------------------------------------------------------------------------- Br| 271 270 121 177 280 274 203 283 204 281 277 237 160 141 3179 Fd| 297 73 131 331 349 174 328 173 286 353 308 151 118 3343 Hn| 76 110 272 302 134 328 212 235 298 307 199 161 3201 Kb| 208 95 77 196 80 156 116 81 49 113 151 1592 Kk| 160 132 326 128 106 192 134 98 66 56 2024 Kp| 333 201 308 163 317 340 275 133 107 3315 La| 173 338 186 290 361 304 159 129 3407 Mk| 165 101 238 175 144 50 51 2331 Nl| 196 269 334 312 174 141 3384 Ny| 145 181 170 261 244 2498 Ov| 296 236 104 84 3089 Pt| 301 155 126 3412 Sc| 173 139 3053 Wz| 261 2159 Zc| 1909 Number of 2-station scans: 150 Number of 3-station scans: 158 Number of 4-station scans: 100 Number of 5-station scans: 53 Number of 6-station scans: 35 Number of 7-station scans: 40 Number of 8-station scans: 44 Number of 9-station scans: 41 Number of 10-station scans: 46 Number of 11-station scans: 69 Number of 12-station scans: 63 Number of 13-station scans: 30 Number of 14-station scans: 13 Number of 15-station scans: 15 Total # of scans, observations: 857 20948 SOURCE SELECTION ================ There are a total of 94 sources scheduled in this session. Among them, 30 sources are from the astrometric monitoring list and 50 are from the geodetic and monitoring lists. Six non-geodetic sources with poorly determined ICRF2 positions are being re-observed to improve their positions. There are 8 new sources requested by L. Petrov to compare VLBA positions with LBA positions. These 14 sources are observed in two scans each at the VLBA sites. The goal is to accurately determine their coordinates. They are not optimized for imaging. 0046+861 $ 00 52 32.85486 +86 27 44.2505 2000.0 0.0 Poor ICRF2 position 0130-447 $ 01 33 00.86354 -44 30 43.6390 2000.0 0.0 Poor ICRF2 position 0822-152 $ 08 24 51.62141 -15 27 45.9154 2000.0 0.0 Poor ICRF2 position 1256+802 $ 12 57 31.72586 +79 58 02.4888 2000.0 0.0 Poor ICRF2 position 1936+095 $ 19 38 43.64956 +09 42 19.2012 2000.0 0.0 Poor ICRF2 position 2322-411 $ 23 25 03.38032 -40 51 30.0683 2000.0 0.0 Poor ICRF2 position 0912-330 $ 09 14 36.68 -33 14 52.0 2000.0 0.0 Request/Petrov 1247-442 $ 12 50 22.88 -44 32 04.4 2000.0 0.0 Request/Petrov 1511-360 $ 15 14 38.42 -36 16 59.4 2000.0 0.0 Request/Petrov 1753-418 $ 17 57 15.62 -41 49 18.7 2000.0 0.0 Request/Petrov 1826-447 $ 18 30 00.87 -44 41 11.8 2000.0 0.0 Request/Petrov 2045-405 $ 20 49 10.00 -40 20 31.3 2000.0 0.0 Request/Petrov 2221-387 $ 22 24 44.02 -38 31 32.9 2000.0 0.0 Request/Petrov 2327-376 $ 23 30 35.82 -37 24 39.3 2000.0 0.0 Request/Petrov 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: NOTE: THERE ARE SOME CHANGES FROM PREVIOUS EXPERIMENTS FOR 2-BIT SAMPLING. ============================================================ The data will be recorded using the following setup: 8 channels 1:2 fan-out 16 MHz sample rate 2-bit sampling This recording mode is designated 256-8(RDV). There is no correlator speed-up factor. 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. 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 1 725.99 3 2 X 8475.99 10,12,14,16 7900 B 575.99| 7680 1 795.99 4 3 X 8790.99 18,20,22,24 7900 B 890.99| 8080 3 710.99 5 4 X 8895.99 26,28,30,32 7900 B 995.99| 8080 3 815.99 6 5 S 2232.99 3, 5, 7, 9 2900 A 667.01| 1600 2 632.99 9 6 S 2262.99 11,13,15,17 2900 A 637.01| 1600 2 662.99 10 7 S 2352.99 19,21,23,25 2900 A 547.01| 1600 2 752.99 13 8 S 2372.99 27,29,31,33 2900 A 527.01| 1600 2 772.99 14 VLBA | Hobart26, NyAlesund, Wettzell 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 3(H) 4 X 8895.99 26,28,30,32 7900 B 995.99| 8580.1 3 315.89 6 3(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 operations for non-VLBA stations: ========================================= Ny Alesund, and Wettzell: These stations have Mark IV racks. Please use the procedures generated by DRUDG. The IF3 command in the procedure IFDSX assumes that VC3 and VC10 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. The standard wiring is described in "help=if3". If you have questions about the wiring, please contact Brian Corey at Haystack. Kokee and Zelenchenskya: These stations have VLBA4 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. Kashima: This station uses a K4-2 VC and K5 recorder. Use the procedures generated by DRUDG. Be sure to set your rack type to K4-2, not K4-2/M4, if that change has not already been made. Please note you will need to comment out the incorrect VC commands in VCSX8 after the comment about these converters being present, but not used. This will be corrected in a future DRUDG release. The tpicd commands should be benign and do not need to be commented out unless they cause a problem. 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. 7. 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: dec09 directory on aspen: /astronomy/dec09/rdv78 or /home/archive/e2e/archive/operations/VLBA/observe/dec09/rdv78 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.