RDV90 (Astrometric/Geodetic VLBA-90) 2011 DEC 20 17:30 DOY 354 Notes prepared by David Gordon, Ed Himwich and John Gipson NVI/GSFC Special notes for this experiment ================================= This session will use 2-bit sampling again, as in the last few 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. There are 8 non-VLBA stations scheduled (FORTLEZA, HARTRAO, KASHIM34, KOKEE, NYALES20, TICOCONC, TSUKUB32, and WETTZELL). These stations should see the "Special operations notes for non-VLBA stations" section below for special instructions. To facilitate fringe-finding, there are several long scans on fairly strong sources at the beginning, in the middle, and at the end. All stations please try to be onsource and recording data for the first of these scans. These scans are: Source Start DURATIONS name yyddd-hhmmss Br Fd Ft Hh Hn Kb Kk Kp La Mk Nl Ny Ov Pt Sc Tc Ts Wz 1803+784 11354-173000| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 0955+476 11354-173626| 45 45 45 45 45 | 2141+175 11354-173739| 300 300 300 300 300 300 300 300 300 300 300 300 300| 0016+731 11355-010805| 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200| 0016+731 11355-035829| 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200| 1053+704 11355-080821| 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200| 1803+784 11355-134956| 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200| 1053+704 11355-170818| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 2141+175 11355-171503| 300 300 300 300 300 300 300 300 300 300 300| 1803+784 11355-172153| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| Additional Notes: - Two-bit sampling is used. - In this RDV, all stations will record on Mark5A/B, except Tsukuba and Kashima. Tsukuba and Kashima will record on K5 and the data will be later transferred to Mark5A at Haystack Observatory. - The synch time for the VLBA DiFX correlator using Mark5 is only a few seconds. Because of this, the 'early' start has been reduced to 10 seconds. - The fluxes use our most recent models. Purpose ======= This is the sixth of six coordinated astrometric/geodetic sessions in 2011 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: rdv90.skd On ftp.aoc.nrao.edu (aspen): VLBA Pointing files: rdv90crd.br rdv90crd.fd rdv90crd.hn rdv90crd.kp rdv90crd.la rdv90crd.mk rdv90crd.nl rdv90crd.ov rdv90crd.pt rdv90crd.sc Summary file: rdv90.sksum Sked file: rdv90.skd Text file: rdv90.txt Vex file: rdv90.vex At IVS Data Center (ftp://cddisa.gsfc.nasa.gov/vlbi/ivsdata/aux/2011/rdv90) Sked file: rdv90.skd Text file: rdv90.txt This experiment uses the 10 VLBA stations and 8 IVS stations. The IVS stations are: FORTLEZA, HARTRAO, KASHIM34, KOKEE, NYALES20, TIGOCONC, TSUKUB32, and WETTZELL. Below is the sked summary: Br=BR-VLBA Fd=FD-VLBA Ft=FORTLEZA Hh=HARTRAO 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 Tc=TIGOCONC Ts=TSUKUB32 Wz=WETTZELL Br Fd Ft Hh Hn Kb Kk Kp La Mk Nl Ny Ov Pt Sc Tc Ts Wz Avg % obs. time: 48 51 51 48 50 34 36 50 52 44 51 42 47 52 49 33 33 42 45 % cal. time: 4 4 3 3 3 4 4 4 4 4 4 3 4 4 3 2 4 3 3 % slew time: 23 23 30 40 21 38 18 22 23 25 22 17 23 23 23 2 16 10 23 % idle time: 24 21 15 9 25 23 41 23 21 26 22 36 25 20 24 62 46 44 29 total # scans: 304 311 218 219 288 366 309 311 315 324 304 293 309 317 292 140 364 275 292 # scans/hour : 13 13 9 9 12 15 13 13 13 14 13 12 13 13 12 6 15 11 12 Avg scan (sec): 136 142 204 190 149 79 102 138 142 117 145 125 133 141 146 206 79 131 138 # data tracks: 16 16 16 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 16 16 16 Total GBytes: 1597 1705 1678 1575 1643 1175 1245 1654 1718 1480 1697 1427 1586 1724 1635 1090 1160 1400 1510 Total GB(M5): 1419 1515 1491 1400 1461 1044 1106 1470 1527 1315 1509 1268 1410 1532 1453 969 1032 1244 1343 # OF OBSERVATIONS BY BASELINE | Br Fd Ft Hh Hn Kb Kk Kp La Mk Nl Ny Ov Pt Sc Tc Ts Wz StnTotal ---------------------------------------------------------------------------------------------------- Br| 233 38 25 190 101 115 237 245 177 226 122 235 247 159 22 119 84 2575 Fd| 55 42 209 68 104 276 298 169 258 88 245 299 201 52 87 75 2759 Ft| 190 90 11 7 42 57 8 70 99 26 54 107 87 10 139 1090 Hh| 76 18 0 28 45 0 58 89 13 41 93 78 19 138 953 Hn| 60 65 191 214 117 240 136 170 212 223 45 77 123 2438 Kb| 198 85 75 154 68 124 95 76 38 0 333 88 1592 Kk| 125 111 232 86 69 148 113 55 10 171 35 1644 Kp| 279 192 240 78 273 284 175 41 103 60 2709 La| 177 267 94 250 311 201 47 94 80 2845 Mk| 145 54 217 180 110 14 171 25 2142 Nl| 115 214 265 217 40 86 99 2694 Ny| 72 94 113 23 125 201 1696 Ov| 256 152 27 112 50 2555 Pt| 199 45 95 76 2847 Sc| 76 55 113 2287 Tc| 0 42 649 Ts| 85 1742 Wz| 1513 Number of 2-station scans: 205 Number of 3-station scans: 146 Number of 4-station scans: 159 Number of 5-station scans: 46 Number of 6-station scans: 49 Number of 7-station scans: 47 Number of 8-station scans: 33 Number of 9-station scans: 40 Number of 10-station scans: 66 Number of 11-station scans: 67 Number of 12-station scans: 24 Number of 13-station scans: 19 Number of 14-station scans: 11 Number of 15-station scans: 12 Number of 16-station scans: 2 Number of 17-station scans: 0 Number of 18-station scans: 0 Number of 19-station scans: 0 Total # of scans, observations: 926 18365 INTENSIVE BREAKS ================ There are expected to be two 1-hr UT1 Intensive sessions during RDV90. One is the regular IVS INT01, using KOKEE and WETTZELL. Therefore, these stations are not scheduled here from 285-1815 to 285-1945 for the INT01. The other is a possible USNO/NRAO UT1 intensive session using PIETOWN and MK-VLBA. The timing for this is somewhat flexible - sometime between 15:00 and 23:00 UTC. Therefore, we expext that PT and MK will be taken out of RDV90 for an ~1.5-2.0 hr period sometime during that window. We will leave the time of this break to the discretion of the VLBA operators. From our standpoint, there is no particular period that is better or worse than another, and the loss of these two antennas for a short period should have only a minimal effect. SOURCE SELECTION ================ There are a total of 90 sources scheduled in this session. Among them, 30 sources are from the astrometric monitoring list, 40 are from the geodetic monitoring list, and 20 are previously observed sources that have only a few observations or were observed in only one session or that had that very large apriori position errors in a previous session. 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. The following tables list the setup for the VLBA stations, the geodetic stations with K5 back ends, and the geodetic stations with Mark IV back ends. These are the SAME frequencies used in all the standard RDV sessions. VLBA | TSUKUB32 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 FORTLEA, NYALES20, VLBA | HARTRAO, 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 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 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 | Kashima34 M B Chan Sky Tracks LO IF BBC | LO IF BBC # # 1 X 8405.99 2, 4, 6, 8 7900 B 505.99| 7580 1 825.99 3 7 2 X 8475.99 10,12,14,16 7900 B 575.99| 7580 1 895.99 4 8 3 X 8790.99 18,20,22,24 7900 B 890.99| 8080 3 710.99 5 1 4 X 8895.99 26,28,30,32 7900 B 995.99| 8080 3 815.99 6 2 5 S 2232.99 3, 5, 7, 9 2900 A 667.01| 1520 2 712.99 9 15 6 S 2262.99 11,13,15,17 2900 A 637.01| 1520 2 742.99 10 16 7 S 2352.99 19,21,23,25 2900 A 547.01| 1520 2 832.99 13 11 8 S 2372.99 27,29,31,33 2900 A 527.01| 1520 2 852.99 14 12 M#: Main recording channel number B#: Backup recording channel number VLBA | TIGOCONC Chan Sky Tracks LO IF BBC | LO IF BBC # 1 X 8405.99 2, 4, 6, 8 7900 B 505.99| 7600.1 A 805.89 3 2 X 8475.99 10,12,14,16 7900 B 575.99| 7600.1 A 875.89 4 3 X 8790.99 18,20,22,24 7900 B 890.99| 8080 C 710.99 5 4 X 8895.99 26,28,30,32 7900 B 995.99| 8080 C 815.99 6 5 S 2232.99 3, 5, 7, 9 2900 A 667.01| 1540.1 B 692.89 9 6 S 2262.99 11,13,15,17 2900 A 637.01| 1540.1 B 722.89 10 7 S 2352.99 19,21,23,25 2900 A 547.01| 1540.1 B 812.89 13 8 S 2372.99 27,29,31,33 2900 A 527.01| 1540.1 B 832.89 14 Special operations for non-VLBA stations: ========================================= FORTLEZA, HARTRAO, Ny Alesund, and Wettzell: These stations have Mark IV or Mark 5 racks. Please use the procedures generated by DRUDG. VCs 3 & 4 are used at X-band with IF 1. VCs 5 & 6 are used at X-band with IF 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. Tsukuba32 and KASHIM34: These stations use K4-2 VCs and a K5 recorder. Please transfer data to Haystack in Mark IV format. 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 the VCSX8 procedure after the comment about these converters being present, but not used. This will be corrected in a future DRUDG release. Please also set the attenuation and detector appropriately in the va=.. and vb=... commands. The tpicd commands in SX8M12A should be benign and do not need to be commented out unless they cause a problem. If you wish to record back-up channels, please add appropriate valo=..., va=... vblo=... and vb=... commands in the VCSX8 procedure. Kokee and TIGOCONC These stations have a VLBA5/Mark5B 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. 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 the 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 cddisin.gsfc.nasa.gov/ivsincoming directory on vlbeer: dec11 directory on aspen: /astronomy/dec11/rdv90 or /home/archive/e2e/archive/operations/VLBA/observe/dec11/rdv90 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 (except Tsukuba and Kashima) to Socorro as soon after the experiment as practical. The Tsukuba and Kashima data should be e-transfered to Haystack in Mark IV format as soon after the experiment as is practical. Media should be shipped to: VLBA Array Operations Center National Radio Astronomy Observatory Attn: Juan Cordova 1003 Lopezville Road Socorro, NM 87801 U.S.A. Phone: 575-835-7000 Shipping and VLBA contact information is also given at: https://science.nrao.edu/facilities/vlba/contact/shipping_information. Please use one of the recommended shipping companies (FedEx, UPS, DHL, TNT). The VLBA needs to process the session at their correlator as soon as possible because of limited media. They prefer to have the data within one week of the observation, but in no case later than two weeks after the observation. If a station's media takes longer than this to arrive, correlation may be done without it. Therefore, all stations participating in the RDV sessions, please ship your media to the VLBA the same day the session ends or the next business day (just like the R1/R4 media is shipped). If you know that there is going to be a problem sending your media to the VLBA the same day the session ends or the next business day, please let us (ivscc@ivscc.gsfc.nasa.gov and David.Gordon-1@nasa.gov) know as soon as possible so that we, along with the VLBA, can determine the best course of action. If you have any questions or comments, please let us know.