RDV80 (Astrometric/Geodetic VLBA-80) 2010 Aug. 04 18:00 Day 216 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 3 previous RDV's. 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 4 non-VLBA stations with Mark IV and VLBA4 racks (Kokee, Matera, Ny Alesund, and Tsukuba) should see the "Special operations notes for non-VLBA stations" section below for special instructions. The schedule begins and ends with full network scans that can be used for fringe finding. There is also a full network scan right after Kokee's Intensive break, and scattered throughout the schedule. These scans are: Source Start DURATIONS name yyddd-hhmmss Br Fd Hn Kk Kp La Ma Mk Nl Ny Ov Pt Sc Ts 1803+784 10216-180000| 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 1053+704 10216-194945| 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 1342+662 10216-201608| 152 155 113 174 156 150 174 108 134 136 155 153 139 94| 0718+793 10216-205210| 84 285 480 480 161 187 288 125 299 84 113 182 480 480| 1803+784 10216-233558| 40 40 40 40 40 40 40 40 40 40 40 40 40 40| 1327+504 10217-004448| 480 480 480 480 480 480 480 480 480 480 480 480 480 480| NRAO512 10217-025237| 40 40 40 111 40 40 111 66 40 48 40 40 40 40| 1342+662 10217-034101| 133 156 119 155 154 150 170 87 137 155 152 153 170 94| 2229+695 10217-034452| 74 77 60 91 77 73 91 58 73 77 76 75 63 45| 1803+784 10217-035359| 40 40 40 40 40 40 40 40 40 40 40 40 40 40| 1739+522 10217-041446| 40 40 40 40 40 40 40 40 40 40 40 40 40 40| 0718+793 10217-041718| 480 480 303 480 480 480 480 480 321 480 480 480 480 480| 1803+784 10217-100121| 120 120 120 120 120 120 120 120 120 120 120 120 120 120| 0059+581 10217-111453| 40 40 40 43 40 40 43 40 40 40 40 40 40 40| 1803+784 10217-135420| 40 40 40 40 40 40 40 40 40 40 40 40 40 40| 2229+695 10217-135554| 73 78 64 75 76 74 88 40 76 75 75 76 88 45| 0718+793 10217-150917| 480 480 206 480 480 480 480 480 480 480 480 480 295 480| 1053+704 10217-175009| 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 1803+784 10217-175652| 180 180 180 180 180 180 180 180 180 180 180 180 180 180| Additional Notes: - Two-bit sampling is used. - In this RDV, all stations will record on Mark5A, except Tsukuba. The K5 Tsukuba data will be 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. - The fluxes use our most recent models. Purpose ======= This is the second of six coordinated astrometric/geodetic experiments in 2010 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: rdv80.skd On ftp.aoc.nrao.edu (aspen): VLBA Pointing files: rdv80crd.br rdv80crd.fd rdv80crd.hn rdv80crd.kp rdv80crd.la rdv80crd.mk rdv80crd.nl rdv80crd.ov rdv80crd.pt rdv80crd.sc Summary file for correlator: rdv80.sksum Sked file: rdv80.skd Text file: rdv80.txt Vex file: rdv80.vex At IVS Data Center (ftp://cddisa.gsfc.nasa.gov/vlbi/ivsdata/aux/2010/rdv80) Sked file: rdv80.skd Text file: rdv80.txt This experiment uses the 10 VLBA stations and 4 IVS stations. The IVS stations are: KOKEE, MATERA, NYALES20, and TSUKUB32. Below is the sked summary: Total time: 1440 minutes ( 24.0 hours). Key: Br=BR-VLBA Fd=FD-VLBA Hn=HN-VLBA Kk=KOKEE Kp=KP-VLBA La=LA-VLBA Ma=MATERA Mk=MK-VLBA Nl=NL-VLBA Ny=NYALES20 Ov=OV-VLBA Pt=PIETOWN Sc=SC-VLBA Ts=TSUKUB32 Br Fd Hn Kk Kp La Ma Mk Nl Ny Ov Pt Sc Ts Avg % obs. time: 54 58 53 47 57 57 51 46 55 51 54 57 55 35 52 % cal. time: 4 4 4 4 4 4 3 5 4 4 4 4 4 4 4 % slew time: 24 22 24 19 23 23 25 29 23 20 25 23 23 18 23 % idle time: 17 16 18 29 15 16 20 20 17 24 17 15 17 42 21 total # scans: 316 319 328 363 329 322 278 397 319 313 335 320 316 386 331 # scans/hour : 13 13 14 15 14 13 12 17 13 13 14 13 13 16 14 Avg scan (sec): 148 156 140 111 150 153 159 100 149 142 138 155 150 79 137 # data tracks: 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 Total GBytes: 2029 2141 2011 1839 2134 2124 1892 1860 2054 1933 2031 2126 2046 1509 1981 Total GB(M5): 1803 1903 1788 1634 1897 1888 1682 1653 1825 1719 1805 1890 1818 1341 1761 # OF OBSERVATIONS BY BASELINE | Br Fd Hn Kk Kp La Ma Mk Nl Ny Ov Pt Sc Ts StnTotal -------------------------------------------------------------------------------- Br| 238 240 148 252 245 128 190 238 175 255 244 213 114 2680 Fd| 268 117 305 315 131 171 297 137 260 314 283 71 2907 Hn| 104 257 267 158 141 279 163 220 266 279 74 2716 Kk| 136 122 59 312 112 109 164 122 99 242 1846 Kp| 309 122 190 288 137 283 309 271 85 2944 La| 133 176 300 142 267 320 280 75 2951 Ma| 51 136 230 104 132 141 121 1646 Mk| 164 98 227 176 149 238 2283 Nl| 147 252 299 284 75 2871 Ny| 133 142 135 164 1912 Ov| 266 230 112 2773 Pt| 279 75 2944 Sc| 53 2696 Ts| 1499 Number of 2-station scans: 124 Number of 3-station scans: 234 Number of 4-station scans: 61 Number of 5-station scans: 17 Number of 6-station scans: 23 Number of 7-station scans: 30 Number of 8-station scans: 34 Number of 9-station scans: 37 Number of 10-station scans: 52 Number of 11-station scans: 87 Number of 12-station scans: 24 Number of 13-station scans: 28 Number of 14-station scans: 20 Total # of scans, observations: 771 17334 SOURCE SELECTION ================ There are a total of 90 sources scheduled in this session. Among them, 30 sources are from the astrometric monitoring list and 45 are from the geodetic monitoring list. There are also 9 previously observed sources that have only a few observations and large adjustments from their original apriori positions, and 6 new sources requested by L. Petrov and C. Phillips. These 15 sources are observed in two scans each at the VLBA sites, with the goal of accurately determining their coordinates. They are not optimized for imaging. These 15 sources are: 0409-280 $ 04 11 25.23205 -27 58 20.8214 2000.0 0.0 Large adj. 0446+462 $ 04 50 30.80144 +46 20 59.7952 2000.0 0.0 Large adj. 1004+054 $ 10 06 37.61428 +05 09 54.0931 2000.0 0.0 Large adj. 1009-041 $ 10 11 30.23960 -04 23 27.7074 2000.0 0.0 Large adj. 1241+176 $ 12 44 10.82443 +17 21 04.5138 2000.0 0.0 Large adj. 1412+087 $ 14 15 09.91862 +08 32 05.3691 2000.0 0.0 Large adj. 1437+061 $ 14 40 17.98469 +05 56 34.0888 2000.0 0.0 Large adj. 1442-245 $ 14 45 44.21139 -24 45 41.5939 2000.0 0.0 Large adj. 1843-001 $ 18 46 03.78270 -00 03 38.2790 2000.0 0.0 Large adj. 0557-454 $ 05 59 11.53 -45 29 40.3 2000.0 0.0 Requested 0647-410 $ 06 49 14.12 -41 08 53.5 2000.0 0.0 Requested 0725-381 $ 07 27 00.20 -38 13 11.4 2000.0 0.0 Requested 1621-321 $ 16 24 59.64 -32 13 23.4 2000.0 0.0 Requested 1653-329 $ 16 56 16.83 -33 02 07.7 2000.0 0.0 Requested 2131-340 $ 21 34 50.80 -33 51 14.4 2000.0 0.0 Requested SCHEDULING ALGORITHMS ===================== This schedule uses the "SRCEVN SQRT" mode of Sked. In the absence 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 | NyAlesund, Matera 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 L 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 Matera: These stations have Mark IV racks. Please use the procedures generated by DRUDG. VCs 3, 4, 5, & 6 are used at X-band with IFs 1 and 3. VCs 9, 10, 13, & 14 are used at S-band with IF B. 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: This station has a VLBA4 back end. 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. Tsukuba: 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: aug10 directory on aspen: /astronomy/aug10/rdv80 or /home/archive/e2e/archive/operations/VLBA/observe/aug10/rdv80 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 on the VLBA-DiFX software correlator. Disks should be shipped to Socorro as soon after the experiment as practical.