COVER INFORMATION Station: SVETLOE (Code Sv ) Experiment: 18cm global VLBI observations of Arp220 Exp. Code: GV022A Schedule Version: 5.00 Processed by SCHED version: 11.40 Release 11.4. March 14, 2015 PI: Eskil Varenius Address: Department of Earth and Space Sciences, Chalmers University of T Onsala Space Observatory 439 92 Onsala Sweden Phone: +46 31 772 55 45 EMAIL: varenius@chalmers.se Fax: +46(0)31 772 5590 Phone during observation: +46 31 772 55 45 Observing mode: 18cm 2Gbps global VLBI with phased D-array VLA Notes: Phase calibrator : J1532+2344 Fringe finder / pol. cal / bandpass cal : J1516+1932 VLA phase-up calibrator: J1520+2016 (3C318) Schedule for SVETLOE (Code Sv ) Page 2 18cm global VLBI observations of Arp220 UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Sun 26 Feb 2017 Day 57 --- Next scan frequencies: 1584.25 1584.25 1584.25 1584.25 1616.25 1616.25 1616.25 1616.25 1648.25 1648.25 1648.25 1648.25 1680.25 1680.25 1680.25 1680.25 Next BBC frequencies: 324.25 324.25 324.25 324.25 356.25 356.25 356.25 356.25 388.25 388.25 388.25 388.25 420.25 420.25 420.25 420.25 Next scan bandwidths: 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 03 30 00 J1532+2344 15 53 50 53.0 547.7 0.3 4.1 0 0 03 30 00 03 33 00 =1530+239 15 56 51 52.9 548.9 0.4 4.8 180 23 03 30 01 03 33 25 ARP220 15 57 16 52.7 548.2 0.4 4.4 12 23 03 33 25 03 43 25 --- 16 07 18 52.5 552.0 0.5 6.4 600 100 03 33 26 03 43 51 J1532+2344 16 07 44 52.7 553.0 0.6 6.9 12 100 03 43 51 03 46 51 =1530+239 16 10 44 52.6 554.1 0.6 7.5 180 123 03 43 52 03 47 17 ARP220 16 11 10 52.4 553.4 0.6 7.1 12 123 03 47 17 03 57 17 --- 16 21 11 52.1 557.1 0.8 9.1 600 200 03 47 18 03 57 42 J1532+2344 16 21 37 52.2 558.1 0.8 9.6 12 200 03 57 42 04 00 42 =1530+239 16 24 38 52.1 559.2 0.9 10.2 180 223 03 57 43 04 01 08 ARP220 16 25 03 51.9 558.5 0.8 9.8 12 223 04 01 08 04 11 08 --- 16 35 05 51.5 562.2 1.0 11.7 600 300 04 01 09 04 11 33 J1532+2344 16 35 30 51.6 563.2 1.0 12.2 12 300 04 11 33 04 14 33 =1530+239 16 38 31 51.5 564.3 1.1 12.8 180 323 04 11 34 04 14 59 ARP220 16 38 56 51.3 563.6 1.1 12.4 12 323 04 14 59 04 24 59 --- 16 48 58 50.8 567.1 1.2 14.2 600 400 04 15 00 04 25 52 J1516+1932 16 49 52 45.8 572.0 1.5 16.0 28 400 04 25 52 04 27 52 =1514+197 16 51 52 45.7 572.6 1.6 16.3 120 415 04 25 53 04 28 40 J1532+2344 16 52 40 50.7 569.3 1.3 15.2 23 415 04 28 40 04 31 40 =1530+239 16 55 40 50.5 570.3 1.4 15.7 180 438 04 28 41 04 32 05 ARP220 16 56 06 50.4 569.6 1.3 15.4 12 438 04 32 05 04 42 05 --- 17 06 07 49.7 573.1 1.5 17.0 600 515 04 32 06 04 42 31 J1532+2344 17 06 33 49.8 574.1 1.6 17.5 12 515 04 42 31 04 45 31 =1530+239 17 09 34 49.6 575.1 1.6 18.0 180 538 04 42 32 04 45 56 ARP220 17 09 59 49.5 574.4 1.6 17.6 12 538 04 45 56 04 55 56 --- 17 20 01 48.7 577.7 1.7 19.1 600 615 04 45 57 Schedule for SVETLOE (Code Sv ) Page 3 18cm global VLBI observations of Arp220 UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Sun 26 Feb 2017 Day 57 --- 04 56 22 J1532+2344 17 20 26 48.8 578.7 1.8 19.6 12 615 04 56 22 04 59 22 =1530+239 17 23 27 48.5 579.7 1.8 20.0 180 638 04 56 23 04 59 47 ARP220 17 23 52 48.4 579.0 1.8 19.7 12 638 04 59 47 05 09 47 --- 17 33 54 47.6 582.2 2.0 21.1 600 715 04 59 48 05 10 13 J1532+2344 17 34 20 47.6 583.1 2.0 21.6 12 715 05 10 13 05 13 13 =1530+239 17 37 20 47.4 584.1 2.1 21.9 180 738 05 10 14 05 13 38 ARP220 17 37 46 47.3 583.4 2.0 21.6 13 738 05 13 38 05 23 38 --- 17 47 47 46.5 586.5 2.2 22.9 600 815 05 13 39 05 24 25 J1516+1932 17 48 34 41.1 589.9 2.5 23.5 21 815 05 24 25 05 26 25 =1514+197 17 50 34 40.9 590.5 2.5 23.7 120 831 05 24 26 05 27 10 J1532+2344 17 51 20 46.1 588.4 2.3 23.7 20 831 05 27 10 05 30 10 =1530+239 17 54 20 45.9 589.3 2.3 24.0 180 854 05 27 11 05 30 36 ARP220 17 54 46 45.8 588.6 2.3 23.7 13 854 05 30 36 05 40 36 --- 18 04 48 44.9 591.6 2.5 24.9 600 931 05 30 37 05 41 01 J1532+2344 18 05 13 44.8 592.5 2.5 25.2 13 931 05 41 01 05 44 01 =1530+239 18 08 14 44.5 593.4 2.6 25.5 180 954 05 41 02 05 44 27 ARP220 18 08 39 44.5 592.8 2.5 25.3 13 954 05 44 27 05 54 27 --- 18 18 41 43.5 595.6 2.7 26.3 600 1031 05 44 28 05 54 53 J1532+2344 18 19 07 43.4 596.5 2.8 26.6 13 1031 05 54 53 05 57 53 =1530+239 18 22 07 43.1 597.4 2.8 26.9 180 1054 05 54 54 05 58 18 ARP220 18 22 33 43.1 596.7 2.8 26.6 13 1054 05 58 18 06 08 18 --- 18 32 34 42.1 599.5 2.9 27.5 600 1131 05 58 19 06 08 44 J1532+2344 18 33 00 42.0 600.4 3.0 27.8 13 1131 06 08 44 06 11 44 =1530+239 18 36 01 41.7 601.2 3.0 28.1 180 1154 06 08 45 06 12 09 ARP220 18 36 26 41.6 600.6 3.0 27.8 13 1154 06 12 09 06 22 09 --- 18 46 28 40.6 603.3 3.2 28.6 600 1231 06 12 10 06 22 35 J1532+2344 18 46 53 40.5 604.1 3.2 28.9 13 1231 06 22 35 06 25 35 =1530+239 18 49 54 40.1 604.9 3.3 29.1 180 1254 06 22 36 06 26 00 ARP220 18 50 19 40.1 604.3 3.2 28.9 13 1254 06 26 00 06 36 00 --- 19 00 21 39.0 606.9 3.4 29.5 600 1331 06 26 01 Schedule for SVETLOE (Code Sv ) Page 4 18cm global VLBI observations of Arp220 UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Sun 26 Feb 2017 Day 57 --- 06 36 00 J1516+1932 19 00 21 33.5 609.0 3.7 29.1 -26 1331 No stop 06 37 00 =1514+197 19 01 21 33.4 609.2 3.7 29.2 34 1338 06 36 01 06 37 21 J1516+1932 19 01 43 33.3 609.3 3.7 29.2 15 1338 06 37 14 06 38 21 =1514+197 19 02 43 33.2 609.6 3.7 29.3 60 1347 06 37 15 06 39 12 J1532+2344 19 03 34 38.6 608.4 3.5 30.0 25 1347 06 39 12 06 42 12 =1530+239 19 06 34 38.2 609.2 3.6 30.1 180 1370 06 39 13 06 42 38 ARP220 19 07 00 38.3 608.6 3.5 29.9 13 1370 06 42 38 06 52 38 --- 19 17 02 37.1 611.1 3.7 30.5 600 1447 06 42 39 06 53 04 J1532+2344 19 17 27 37.0 611.9 3.7 30.7 13 1447 06 53 04 06 56 04 =1530+239 19 20 28 36.6 612.6 3.8 30.8 180 1470 06 53 05 06 56 29 ARP220 19 20 53 36.6 612.0 3.8 30.7 13 1470 06 56 29 07 06 29 --- 19 30 55 35.5 614.5 3.9 31.1 600 1547 06 56 30 07 06 55 J1532+2344 19 31 21 35.3 615.3 4.0 31.3 13 1547 07 06 55 07 07 55 =1530+239 19 32 21 35.2 615.5 4.0 31.3 60 1555 07 06 56 07 08 15 J1532+2344 19 32 41 35.2 615.6 4.0 31.3 14 1555 07 08 15 07 10 15 =1530+239 19 34 41 35.0 616.0 4.0 31.4 120 1570 07 08 16 07 10 40 ARP220 19 35 07 35.0 615.5 4.0 31.3 13 1570 07 10 40 07 20 40 --- 19 45 08 33.8 617.9 4.2 31.6 600 1647 07 10 41 07 21 06 J1532+2344 19 45 34 33.6 618.6 4.2 31.8 13 1647 07 21 06 07 24 06 =1530+239 19 48 35 33.3 619.3 4.3 31.9 180 1670 07 21 07 07 24 31 ARP220 19 49 00 33.3 618.8 4.2 31.7 13 1670 07 24 31 07 34 31 --- 19 59 02 32.1 621.1 4.4 32.0 600 1747 07 24 32 07 35 25 J1516+1932 19 59 56 26.4 623.0 4.7 31.2 28 1747 07 35 25 07 36 25 =1514+197 20 00 56 26.3 623.2 4.7 31.2 60 1755 07 35 26 07 36 45 J1516+1932 20 01 16 26.2 623.3 4.7 31.2 14 1755 07 36 45 07 37 45 =1514+197 20 02 17 26.1 623.5 4.7 31.2 60 1763 07 36 46 07 38 38 J1532+2344 20 03 09 31.5 622.7 4.5 32.2 27 1763 07 38 38 07 41 38 =1530+239 20 06 10 31.1 623.4 4.5 32.2 180 1786 07 38 39 07 41 59 ARP220 20 06 31 31.2 622.8 4.5 32.1 9 1786 07 41 59 07 51 59 --- 20 16 32 29.9 625.1 4.7 32.3 600 1863 07 42 00 Schedule for SVETLOE (Code Sv ) Page 5 18cm global VLBI observations of Arp220 UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Sun 26 Feb 2017 Day 57 --- 07 52 20 J1532+2344 20 16 54 29.8 625.8 4.7 32.4 9 1863 07 52 20 07 55 20 =1530+239 20 19 54 29.5 626.4 4.8 32.4 180 1886 07 52 21 07 55 41 ARP220 20 20 15 29.5 625.9 4.7 32.3 9 1886 07 55 41 08 05 41 --- 20 30 17 28.3 628.1 4.9 32.4 600 1963 07 55 42 08 06 02 J1532+2344 20 30 38 28.1 628.8 5.0 32.5 9 1963 08 06 02 08 07 02 =1530+239 20 31 38 28.0 629.0 5.0 32.5 60 1970 08 06 03 08 07 12 J1532+2344 20 31 48 28.0 629.1 5.0 32.5 4 1970 08 07 12 08 09 12 =1530+239 20 33 49 27.8 629.5 5.0 32.5 120 1986 08 07 13 08 09 33 ARP220 20 34 09 27.8 629.0 5.0 32.4 9 1986 08 09 33 08 19 33 --- 20 44 11 26.6 631.1 5.1 32.4 600 2063 08 09 34 08 19 54 J1532+2344 20 44 32 26.4 631.8 5.2 32.5 9 2063 08 19 54 08 22 54 =1530+239 20 47 33 26.1 632.5 5.2 32.5 180 2086 08 19 55 08 23 14 ARP220 20 47 53 26.1 631.9 5.2 32.4 8 2086 08 23 14 08 33 14 --- 20 57 55 24.9 634.1 5.4 32.3 600 2163 08 23 15 08 34 10 J1516+1932 20 58 50 19.2 635.9 5.7 31.3 29 2163 08 34 10 08 35 10 =1514+197 20 59 50 19.1 636.1 5.7 31.3 60 2170 08 34 11 08 35 20 J1516+1932 21 00 00 19.0 636.1 5.7 31.3 4 2170 08 35 20 08 36 20 =1514+197 21 01 00 18.9 636.3 5.7 31.2 60 2178 08 35 21 08 37 12 J1532+2344 21 01 53 24.3 635.5 5.5 32.3 27 2178 08 37 12 08 40 12 =1530+239 21 04 54 23.9 636.2 5.5 32.3 180 2201 08 37 13 08 40 33 ARP220 21 05 14 24.0 635.6 5.5 32.2 8 2201 08 40 33 08 50 33 --- 21 15 16 22.7 637.8 5.7 32.1 600 2278 08 40 34 08 50 53 J1532+2344 21 15 36 22.6 638.4 5.7 32.1 9 2278 08 50 53 08 53 53 =1530+239 21 18 37 22.3 639.1 5.8 32.0 180 2301 08 50 54 08 54 13 ARP220 21 18 57 22.3 638.5 5.7 32.0 8 2301 08 54 13 09 04 13 --- 21 28 58 21.1 640.6 5.9 31.8 600 2378 08 54 14 09 04 34 J1532+2344 21 29 19 21.0 641.3 5.9 31.8 8 2378 09 04 34 09 05 34 =1530+239 21 30 19 20.8 641.5 5.9 31.8 60 2386 09 04 35 09 05 45 J1532+2344 21 30 31 20.8 641.5 5.9 31.8 6 2386 09 05 45 09 07 45 =1530+239 21 32 31 20.6 642.0 6.0 31.7 120 2401 09 05 46 Schedule for SVETLOE (Code Sv ) Page 6 18cm global VLBI observations of Arp220 UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Sun 26 Feb 2017 Day 57 --- 09 08 05 ARP220 21 32 51 20.6 641.4 6.0 31.7 8 2401 09 08 05 09 18 05 --- 21 42 53 19.4 643.5 6.1 31.4 600 2478 09 08 06 09 18 25 J1532+2344 21 43 13 19.3 644.2 6.2 31.4 8 2478 09 18 25 09 21 25 =1530+239 21 46 14 18.9 644.8 6.2 31.3 180 2501 09 18 26 09 21 45 ARP220 21 46 33 19.0 644.3 6.2 31.3 8 2501 09 21 45 09 31 45 --- 21 56 35 17.8 646.4 6.3 31.0 600 2578 09 21 46 09 32 41 J1516+1932 21 57 31 12.1 648.2 6.7 29.7 29 2578 09 32 41 09 33 41 =1514+197 21 58 31 12.0 648.4 6.7 29.7 60 2586 09 32 42 09 33 51 J1516+1932 21 58 41 12.0 648.5 6.7 29.7 4 2586 09 33 51 09 34 51 =1514+197 21 59 41 11.9 648.7 6.7 29.6 60 2593 09 33 52 09 35 43 J1532+2344 22 00 34 17.3 647.8 6.5 30.8 27 2593 09 35 43 09 36 43 =1530+239 22 01 34 17.1 648.0 6.5 30.7 60 2601 09 35 44 09 37 03 ARP220 22 01 54 17.2 647.5 6.4 30.8 8 2601 09 37 03 09 47 03 --- 22 11 55 16.0 649.5 6.6 30.4 600 2678 09 37 04 09 47 23 J1532+2344 22 12 15 15.9 650.2 6.6 30.3 8 2678 09 47 23 09 50 23 =1530+239 22 15 16 15.5 650.8 6.7 30.1 180 2701 09 47 24 09 50 43 ARP220 22 15 35 15.6 650.3 6.7 30.2 8 2701 09 50 43 10 00 43 --- 22 25 37 14.4 652.4 6.8 29.7 600 2778 09 50 44 10 01 03 J1532+2344 22 25 57 14.3 653.0 6.9 29.6 8 2778 10 01 03 10 02 03 =1530+239 22 26 57 14.2 653.2 6.9 29.6 60 2786 10 01 04 10 02 21 J1532+2344 22 27 16 14.2 653.3 6.9 29.6 13 2786 10 02 21 10 04 21 =1530+239 22 29 16 14.0 653.7 6.9 29.5 120 2801 10 02 22 10 04 41 ARP220 22 29 36 14.0 653.2 6.9 29.5 8 2801 10 04 41 10 14 41 --- 22 39 37 12.8 655.2 7.1 29.0 600 2878 10 04 42 10 15 01 J1532+2344 22 39 57 12.8 655.9 7.1 28.9 8 2878 10 15 01 10 18 01 =1530+239 22 42 58 12.4 656.5 7.2 28.7 180 2901 10 15 02 10 18 20 ARP220 22 43 17 12.4 656.0 7.1 28.8 8 2901 10 18 20 10 28 20 --- 22 53 19 11.3 658.1 7.3 28.2 600 2978 10 18 21 SETUP FILE INFORMATION: NOTE: If DOPPLER, FREQ, or BW were used, see the individual scans for the final BBC settings. ======== Setup file: sess117.L2048glob Matching groups in /home/guest/rmc/SCHED/sched11.4/catalogs/freq_RDBE.dat: kvzr_l passed by Alexey Melnikov, Mar2014 Setup group: 13 Station: SVETLOE Total bit rate: 1024 Format: MARK5B Bits per sample: 2 Sample rate: 32.000 Number of channels: 16 DBE type: Speedup factor: 1.00 Disk used to record data. 1st LO= 1260.00 1260.00 1260.00 1260.00 1260.00 1260.00 1260.00 1260.00 1260.00 1260.00 1260.00 1260.00 1260.00 1260.00 1260.00 1260.00 Net SB= L L U U L L U U L L U U L L U U IF SB = U U U U U U U U U U U U U U U U Pol. = RCP LCP RCP LCP RCP LCP RCP LCP RCP LCP RCP LCP RCP LCP RCP LCP BBC = 1 9 1 9 2 10 2 10 3 11 3 11 4 12 4 12 BBC SB= L L U U L L U U L L U U L L U U IF = A B A B A B A B A B A B A B A B The following frequency sets based on these setups were used. Frequency Set: 8 Setup file default. Used with PCAL = off LO sum= 1584.25 1584.25 1584.25 1584.25 1616.25 1616.25 1616.25 1616.25 1648.25 1648.25 1648.25 1648.25 1680.25 1680.25 1680.25 1680.25 BBC fr= 324.25 324.25 324.25 324.25 356.25 356.25 356.25 356.25 388.25 388.25 388.25 388.25 420.25 420.25 420.25 420.25 Bandwd= 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 16.00 Matching frequency sets: 8 9 10 Track assignments are: track1= 18, 26, 2, 10, 20, 28, 4, 12, 22, 30, 6, 14, 24, 32, 8, 16 barrel=roll_off POSITIONS OF SOURCES USED IN RECORDING SCANS Source Source position (RA/Dec) Error (B1950) (J2000) (Date) (mas) * 3C318 15 17 50.628003 * 15 20 05.489700 15 20 51.619460 0.00 20 26 53.10030 * 20 16 05.61100 20 12 19.37298 0.00 From catalog imbedded in main SCHED input file. Pos. from https://science.nrao.edu/facilities/vla/observing/callist#R15 * ARP220 15 32 46.905485 * 15 34 57.250000 15 35 41.749984 0.00 23 40 07.75728 * 23 30 11.33000 23 26 41.88094 0.00 From catalog imbedded in main SCHED input file. Pos. from Batejat. et al 2011 * 3C286 13 28 49.657758 * 13 31 08.288051 13 31 56.137992 0.18 J1331+3030 30 45 58.64059 * 30 30 32.95924 30 25 07.99101 0.17 1328+307 /home/guest/rmc/SCHED/sched11.4/catalogs/sources.gsfc J1331+30 GSFC 2015a astro solution, unpublished 225 observations. 1514+197 15 14 40.985840 * 15 16 56.796162 15 17 43.268587 0.01 * J1516+1932 19 43 10.94252 * 19 32 12.99209 19 28 23.33097 0.02 J1516+19 /home/guest/rmc/SCHED/sched11.4/catalogs/sources.gsfc GSFC 2015a astro solution, unpublished 2699 observations. 1530+239 15 30 36.092767 * 15 32 46.345222 15 33 30.823776 0.10 * J1532+2344 23 54 09.32921 * 23 44 05.26804 23 40 33.11927 0.17 /home/guest/rmc/SCHED/sched11.4/catalogs/sources.gsfc GSFC 2015a astro solution, unpublished 90 observations. SOURCE SCAN SUMMARY FOR SOURCES LISTED ABOVE Scan hours are for recording scans only. Baseline hours are only counted for scans above horizon at both ends. 'Core' scans are those for which PREEMPT is not 'EXTRA'. The 'DOSCANS' columns are for scans in the range selected by DOSCANS Those are the scans sent to the Vex and other files Source Setup file Frequency sets Core scans (Hours) DOSCANS (duplicates not shown) Scan Baseline Scan Baseline 3C318 sess117.L2048glob 12 18 0.350 0.917 0.433 0.917 ARP220 sess117.L2048glob 1 2 3 4 5 6 7 8 11 12 18 23 8.331 866.845 9.606 914.411 3C286 sess117.L2048glob 18 0.083 0.000 0.083 0.000 J1516+1932 sess117.L2048glob 1 2 3 4 5 6 7 8 11 12 18 23 0.367 34.836 0.433 36.969 J1532+2344 sess117.L2048glob 1 2 3 4 5 6 7 8 11 12 18 23 2.467 256.869 2.917 272.768 EFFECT OF SOLAR CORONA The solar corona can cause unstable phases for sources too close to the Sun. SCHED provides warnings at individual scans for distances less than 10 degrees. The distance from the Sun to each source in this schedule is: Source Sun distance (deg) 3C318 111.1 ARP220 107.8 3C286 134.1 J1516+1932 111.9 J1532+2344 108.3 Barry Clark estimates from predictions by Ketan Desai of IPM scattering sizes that the Sun will cause amplitude reductions on the longest VLBA baselines at a solar distance of 60deg F^(-0.6) where F is in GHz. For common VLBI bands, this is: 327 MHz 117. deg 610 MHz 81. deg 1.6 GHz 45. deg 2.3 GHz 36. deg 5.0 GHz 23. deg 8.4 GHz 17. deg 15.0 GHz 12. deg 22.0 GHz 9. deg 43.0 GHz 6. deg