RDV85 (Astrometric/Geodetic VLBA-85) 2011 FEB. 23 18:00 DOY 054 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 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. The 6 non-VLBA stations (KOKEE, MATERA, NYALES20, TSUKUB32, WESTFORD and WETTZELL) should see the "Special operations notes for non-VLBA stations" section below for special instructions. Kokee and Wettzell will drop out of the RDV85 session at ~18:15 UT to observe the daily UT1 Intensive and will resume RDV85 at ~19:45 UT. The schedul begins and ends with 2 long (300 seconds) full network scans, which are designed to facilitate fringe finding. There is also a 300 second full network scan right after the Intensive break, and several full network scans in the middle of the schedule, which are useful in phase calibration. These scans are: Source Start DURATIONS name yyddd-hhmmss Br Fd Hn Kk Kp La Ma Mk Nl Ny Ov Pt Sc Ts Wf Wz 1803+784 11054-180000| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 3C418 11054-180617| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 2229+695 11054-195359| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 0613+570 11055-011927| 480 480 480 480 480 480 480 480 480 480 480 480 480 480 480 480| 1803+784 11055-022413| 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200| 0302+625 11055-022948| 480 480 480 480 480 480 480 480 480 480 480 480 480 480 480 480| 0800+618 11055-061948| 425 480 255 480 480 427 480 480 300 480 480 480 480 480 480 480| 0955+476 11055-062938| 98 114 71 480 121 106 480 251 83 218 117 111 97 91 211 197| 1803+784 11055-084617| 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200| 1053+704 11055-095534| 124 133 132 231 132 131 480 139 129 480 128 131 159 109 430 293| 2229+695 11055-143739| 105 109 82 285 110 104 285 142 105 212 109 107 87 64 243 109| 2229+695 11055-174904| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| 1803+784 11055-175458| 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300| Additional Notes: - Two-bit sampling is used. - In this RDV, all stations will record on Mark5A, except Tsukuba. Tsukuba will record on K5 and the data will be later transferred to Mark5A. - 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 first of six coordinated astrometric/geodetic experiments 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: rdv85.skd On ftp.aoc.nrao.edu (aspen): VLBA Pointing files: rdv85crd.br rdv85crd.fd rdv85crd.hn rdv85crd.kp rdv85crd.la rdv85crd.mk rdv85crd.nl rdv85crd.ov rdv85crd.pt rdv85crd.sc Summary file: rdv85.sksum Sked file: rdv85.skd Text file: rdv85.txt Vex file: rdv85.vex At IVS Data Center (ftp://cddisa.gsfc.nasa.gov/vlbi/ivsdata/aux/2011/rdv85) Sked file: rdv85.skd Text file: rdv85.txt This experiment uses the 10 VLBA stations and 6 IVS stations. The IVS stations are: KOKEE, MATERA, NYALES20, TSUKUB32, WESTFORD and WETTZELL. Below is the sked summary: 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 Wf=WESTFORD Wz=WETTZELL Br Fd Hn Kk Kp La Ma Mk Nl Ny Ov Pt Sc Ts Wf Wz Avg % obs. time: 57 58 55 44 56 58 59 51 57 59 55 58 54 38 61 49 54 % cal. time: 3 3 4 3 3 3 3 4 3 3 3 3 3 4 3 3 3 % slew time: 22 22 22 17 23 21 23 24 21 14 22 21 23 15 13 10 20 % idle time: 16 16 18 34 16 16 15 21 18 24 19 16 19 42 22 36 22 total # scans: 288 300 304 274 300 297 255 303 300 240 288 296 295 305 234 292 285 # scans/hour : 12 13 13 11 13 12 11 13 13 10 12 12 12 13 10 12 12 Avg scan (sec): 171 166 156 140 163 169 198 144 163 211 165 170 157 107 227 145 165 # data tracks: 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 Total GBytes: 1874 1904 1819 1479 1864 1912 1914 1682 1871 1912 1815 1920 1772 1286 1996 1635 1791 Total GB(M5): 1666 1693 1617 1315 1657 1700 1701 1495 1663 1700 1614 1706 1575 1143 1774 1453 1592 # of tapes : 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 tape change times (hhmm): Total number of tapes: 16.0 Total GBytes (M5) recorded: 25471.4 # OF OBSERVATIONS BY BASELINE | Br Fd Hn Kk Kp La Ma Mk Nl Ny Ov Pt Sc Ts Wf Wz StnTotal ------------------------------------------------------------------------------------------ Br| 222 221 102 222 223 107 152 228 133 220 224 204 108 152 124 2642 Fd| 265 82 266 288 107 136 268 113 223 290 253 63 181 129 2886 Hn| 70 237 270 127 119 282 132 203 266 277 69 198 156 2892 Kk| 108 77 38 232 70 67 129 79 64 181 70 45 1414 Kp| 255 91 162 246 99 253 259 225 83 161 107 2774 La| 112 132 275 118 218 292 253 67 185 134 2899 Ma| 36 119 179 70 110 123 88 144 227 1678 Mk| 121 60 183 133 112 170 72 43 1863 Nl| 127 211 270 265 66 187 146 2881 Ny| 90 116 117 114 148 180 1793 Ov| 222 188 99 129 85 2523 Pt| 251 64 182 132 2890 Sc| 54 184 148 2718 Ts| 56 101 1383 Wf| 141 2190 Wz| 1898 Number of 2-station scans: 139 Number of 3-station scans: 130 Number of 4-station scans: 79 Number of 5-station scans: 39 Number of 6-station scans: 30 Number of 7-station scans: 26 Number of 8-station scans: 27 Number of 9-station scans: 32 Number of 10-station scans: 57 Number of 11-station scans: 35 Number of 12-station scans: 41 Number of 13-station scans: 30 Number of 14-station scans: 14 Number of 15-station scans: 19 Number of 16-station scans: 13 Total # of scans, observations: 711 18662 SOURCE SELECTION ================ There are a total of 90 sources scheduled in this session. Among them, 30 sources are from the astrometric monitoring list, 44 are from the geodetic monitoring list, and 8 are previously observed sources that have only a few observations. There are also 3 sources requested by Adam Deller being reobserved to improve their positions and maps. And there are 5 new sources requested by L. Petrov. The requested sources are observed in two scans each. The requested sources are: 1750-187 17 53 09.0887 -18 43 38.527 Deller/J1753-1843 1855+031 18 58 02.3526 +03 13 16.302 Deller/J1858+0313 1853+027 18 55 35.4365 +02 51 19.569 Deller/J1855+0251 1551-416 15 55 18.50 -41 50 27.0 Petrov/J1555-4150 1750+093 17 53 02.33 +09 19 59.9 Petrov/J1753+0919 1945-325 19 48 25.26 -32 28 08.2 Petrov/J1948-3228 2224-308 22 27 48.20 -30 33 20.0 Petrov/J2227-3033 1801+036 18 03 56.2825 +03 41 07.607 Petrov/J1803+0341 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 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 MATERA, NYALES20, VLBA | WESTFORD, 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 Special operations for non-VLBA stations: ========================================= Matera, Ny Alesund, Westford, and Wettzell: These stations have Mark IV 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. Tsukuba: These stations use K4-2 VCs and a 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 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: 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. 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 cddisin.gsfc.nasa.gov/ivsincoming directory on vlbeer: feb11 directory on aspen: /astronomy/feb11/rdv85 or /home/archive/e2e/archive/operations/VLBA/observe/feb11/rdv85 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) to Socorro as soon after the experiment as practical. The Tsukuba data should be e-transfered to Haystack as soon after the experiment as is practical. 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. So, we are asking all stations, participating in the RDV sessions, to 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) 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.