COVER INFORMATION Station: VLBA_MK (Code Mk ) Experiment: IGR J1746-321 ToO Exp. Code: BM197B Schedule Version: 1.00 Processed by SCHED version: Release of 02 July 2002 PI: Amy Mioduszewski Address: NRAO P. O. Box O Socorro, NM 87801 USA Phone: 505-835-7263 EMAIL: amiodusz@nrao.edu Fax: 505-835-7027 Phone during observation: 505-838-0393 Observing mode: VLBA Notes: Target of Opportunity Schedule for VLBA_MK (Code Mk ) Page 2 IGR J1746-321 ToO UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. TPStart: Tape motion start time. Frequencies are LO sum (band edge). Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) ---------------------------------------------------------------------------------------- --- Tue 8 Apr 2003 Day 98 --- Next scan frequencies: 15349.49 15349.49 15357.49 15357.49 15365.49 15365.49 15373.49 15373.49 Next BBC frequencies: 749.49 749.49 757.49 757.49 765.49 765.49 773.49 773.49 Next scan bandwidths: 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 11 02 00 J1733-1304 13 45 22 25.0 115.7 -3.8 -60.5 0 1 1 0 11 02 00 11 03 00 --- 13 46 22 25.2 115.8 -3.8 -60.4 60 F 1 800 11 06 00 I1746-321 13 49 23 13.1 131.7 -4.0 -56.1 150 1 1 800 11 06 00 11 08 00 --- 13 51 23 13.4 132.0 -3.9 -55.8 120 F 1 2400 11 08 00 W109 13 51 23 14.7 129.0 -4.0 -56.8 -9 1 1 2400 11 08 00 11 09 00 --- 13 52 23 14.9 129.1 -3.9 -56.7 51 F 1 3200 11 09 00 I1746-321 13 52 23 13.6 132.1 -3.9 -55.6 -9 1 1 3200 11 09 00 11 11 00 --- 13 54 24 13.9 132.3 -3.9 -55.3 111 F 1 4800 11 11 00 W109 13 54 24 15.2 129.4 -3.9 -56.4 -9 1 1 4800 11 11 00 11 12 00 --- 13 55 24 15.4 129.5 -3.9 -56.2 51 F 1 5600 11 12 00 I1746-321 13 55 24 14.1 132.5 -3.9 -55.1 -9 1 1 5600 11 12 00 11 14 00 --- 13 57 24 14.5 132.7 -3.8 -54.8 111 F 1 7200 11 14 00 W109 13 57 24 15.8 129.7 -3.9 -55.9 -9 1 1 7200 11 14 00 11 15 00 --- 13 58 24 16.0 129.9 -3.8 -55.8 51 F 1 8000 11 15 00 I1746-321 13 58 24 14.6 132.8 -3.8 -54.7 -9 1 1 8000 11 15 00 11 17 30 --- 14 00 55 15.1 133.2 -3.8 -54.2 141 F 1 10000 11 17 30 GC441 14 00 55 17.6 131.5 -3.7 -54.0 -11 1 1 10000 11 17 30 11 18 30 --- 14 01 55 17.8 131.7 -3.7 -53.8 49 F 1 10800 11 18 30 I1746-321 14 01 55 15.2 133.3 -3.7 -54.1 -11 1 1 10800 11 18 30 11 20 30 --- 14 03 55 15.6 133.5 -3.7 -53.7 109 F 1 12400 11 20 30 GC441 14 03 55 18.1 132.0 -3.6 -53.5 -11 1 1 12400 11 20 30 11 21 30 --- 14 04 55 18.3 132.1 -3.6 -53.3 49 F 1 13200 11 21 30 W56 14 04 55 18.1 130.4 -3.7 -54.5 -7 1 1 13200 11 21 30 11 22 30 --- 14 05 56 18.3 130.6 -3.7 -54.3 53 F 1 14000 Schedule for VLBA_MK (Code Mk ) Page 3 IGR J1746-321 ToO UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. TPStart: Tape motion start time. Frequencies are LO sum (band edge). Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) ---------------------------------------------------------------------------------------- --- Tue 8 Apr 2003 Day 98 --- 11 24 30 J1733-1304 14 07 56 29.7 118.9 -3.4 -57.8 91 1 1 14000 11 24 30 11 25 30 --- 14 08 56 29.9 119.0 -3.4 -57.6 60 F 1 14800 11 25 30 I1746-321 14 08 56 16.4 134.2 -3.6 -52.9 -33 1 1 14800 11 25 30 11 27 30 --- 14 10 56 16.8 134.5 -3.6 -52.5 87 F 1 16400 11 27 30 W109 14 10 56 18.2 131.5 -3.6 -53.7 -9 1 1 16400 11 27 30 11 28 30 --- 14 11 57 18.4 131.7 -3.6 -53.6 51 F 1 17200 11 28 30 I1746-321 14 11 57 16.9 134.6 -3.6 -52.4 -9 1 2 17200 11 28 30 11 30 30 --- 14 13 57 17.3 134.9 -3.5 -52.0 111 R 1 15600 11 30 30 W109 14 13 57 18.7 131.9 -3.6 -53.2 -9 1 2 15600 11 30 30 11 31 30 --- 14 14 57 18.9 132.1 -3.6 -53.1 51 R 1 14800 11 31 30 I1746-321 14 14 57 17.4 135.0 -3.5 -51.8 -9 1 2 14800 11 31 30 11 33 30 --- 14 16 57 17.8 135.3 -3.5 -51.5 111 R 1 13200 11 33 30 W109 14 16 57 19.3 132.4 -3.5 -52.7 -9 1 2 13200 11 33 30 11 34 30 --- 14 17 58 19.4 132.5 -3.5 -52.6 51 R 1 12400 11 34 30 I1746-321 14 17 58 17.9 135.4 -3.5 -51.3 -9 1 2 12400 11 34 30 11 36 30 --- 14 19 58 18.3 135.7 -3.4 -51.0 111 R 1 10800 11 36 30 W109 14 19 58 19.8 132.8 -3.5 -52.2 -9 1 2 10800 11 36 30 11 37 30 --- 14 20 58 19.9 132.9 -3.5 -52.1 51 R 1 10000 11 37 30 I1746-321 14 20 58 18.4 135.9 -3.4 -50.8 -9 1 2 10000 11 37 30 11 40 00 --- 14 23 28 18.8 136.2 -3.4 -50.3 141 R 1 8000 11 40 00 GC441 14 23 28 21.5 134.7 -3.3 -50.2 -11 1 2 8000 11 40 00 11 41 00 --- 14 24 29 21.6 134.9 -3.3 -50.0 49 R 1 7200 11 41 00 I1746-321 14 24 29 19.0 136.3 -3.4 -50.2 -11 1 2 7200 11 41 00 11 43 00 --- 14 26 29 19.3 136.6 -3.3 -49.8 109 R 1 5600 11 43 00 GC441 14 26 29 22.0 135.2 -3.2 -49.6 -11 1 2 5600 11 43 00 11 44 00 --- 14 27 29 22.1 135.4 -3.2 -49.4 49 R 1 4800 11 44 00 W56 14 27 29 22.0 133.6 -3.3 -50.7 -7 1 2 4800 11 44 00 11 45 00 --- 14 28 29 22.2 133.8 -3.3 -50.5 53 R 1 4000 Schedule for VLBA_MK (Code Mk ) Page 4 IGR J1746-321 ToO UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. TPStart: Tape motion start time. Frequencies are LO sum (band edge). Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) ---------------------------------------------------------------------------------------- --- Tue 8 Apr 2003 Day 98 --- 11 47 00 J1733-1304 14 30 30 34.3 122.5 -3.0 -54.6 90 1 2 4000 11 47 00 11 48 00 --- 14 31 30 34.5 122.6 -3.0 -54.4 60 R 1 3200 11 48 00 I1746-321 14 31 30 20.1 137.4 -3.2 -48.9 -35 1 2 3200 11 48 00 11 50 00 --- 14 33 30 20.4 137.7 -3.2 -48.5 85 R 1 1600 11 50 00 W109 14 33 30 22.1 134.8 -3.3 -49.9 -9 1 2 1600 11 50 00 11 51 00 --- 14 34 30 22.2 134.9 -3.2 -49.7 51 R 1 800 11 51 00 I1746-321 14 34 30 20.6 137.8 -3.2 -48.3 -9 1 3 800 11 51 00 11 53 00 --- 14 36 31 20.9 138.1 -3.2 -47.9 111 F 1 800 11 53 00 W109 14 36 31 22.6 135.2 -3.2 -49.3 -9 1 3 800 11 53 00 11 54 00 --- 14 37 31 22.7 135.4 -3.2 -49.2 51 F 1 1600 11 54 00 I1746-321 14 37 31 21.1 138.3 -3.1 -47.8 -9 1 3 1600 11 54 00 11 56 00 --- 14 39 31 21.4 138.6 -3.1 -47.4 111 F 1 3200 11 56 00 W109 14 39 31 23.1 135.7 -3.2 -48.8 -9 1 3 3200 11 56 00 11 57 00 --- 14 40 31 23.2 135.9 -3.1 -48.6 51 F 1 4000 11 57 00 I1746-321 14 40 31 21.5 138.7 -3.1 -47.2 -9 1 3 4000 11 57 00 11 59 00 --- 14 42 32 21.9 139.0 -3.1 -46.8 111 F 1 5600 11 59 00 W109 14 42 32 23.6 136.2 -3.1 -48.2 -9 1 3 5600 11 59 00 12 00 00 --- 14 43 32 23.7 136.3 -3.1 -48.0 51 F 1 6400 12 00 00 I1746-321 14 43 32 22.0 139.2 -3.0 -46.6 -9 1 3 6400 12 00 00 12 02 30 --- 14 46 02 22.4 139.6 -3.0 -46.1 141 F 1 8400 12 02 30 GC441 14 46 02 25.1 138.3 -2.9 -46.0 -11 1 3 8400 12 02 30 12 03 30 --- 14 47 02 25.3 138.5 -2.9 -45.8 49 F 1 9200 12 03 30 I1746-321 14 47 02 22.5 139.8 -3.0 -45.9 -11 1 3 9200 12 03 30 12 05 30 --- 14 49 03 22.9 140.1 -3.0 -45.5 109 F 1 10800 12 05 30 GC441 14 49 03 25.6 138.8 -2.9 -45.4 -11 1 3 10800 12 05 30 12 06 30 --- 14 50 03 25.7 139.0 -2.9 -45.2 49 F 1 11600 12 06 30 W56 14 50 03 25.8 137.2 -2.9 -46.5 -7 1 3 11600 12 06 30 12 07 30 --- 14 51 03 25.9 137.4 -2.9 -46.3 53 F 1 12400 Schedule for VLBA_MK (Code Mk ) Page 5 IGR J1746-321 ToO UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. TPStart: Tape motion start time. Frequencies are LO sum (band edge). Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) ---------------------------------------------------------------------------------------- --- Tue 8 Apr 2003 Day 98 --- 12 09 30 J1733-1304 14 53 03 38.7 126.6 -2.7 -50.8 89 1 3 12400 12 09 30 12 10 30 --- 14 54 04 38.9 126.8 -2.7 -50.7 60 F 1 13200 12 10 30 I1746-321 14 54 04 23.6 140.9 -2.9 -44.6 -37 1 3 13200 12 10 30 12 12 30 --- 14 56 04 23.9 141.2 -2.8 -44.2 83 F 1 14800 12 12 30 W109 14 56 04 25.7 138.4 -2.9 -45.7 -10 1 3 14800 12 12 30 12 13 30 --- 14 57 04 25.9 138.6 -2.9 -45.5 50 F 1 15600 12 13 30 I1746-321 14 57 04 24.0 141.4 -2.8 -44.0 -10 1 3 15600 12 13 30 12 15 30 --- 14 59 04 24.3 141.7 -2.8 -43.5 110 F 1 17200 12 15 30 W109 14 59 04 26.2 138.9 -2.8 -45.1 -10 1 4 17200 12 15 30 12 16 30 --- 15 00 04 26.3 139.1 -2.8 -44.9 50 R 1 16400 12 16 30 I1746-321 15 00 04 24.5 141.9 -2.8 -43.3 -10 1 4 16400 12 16 30 12 18 30 --- 15 02 05 24.8 142.2 -2.7 -42.9 110 R 1 14800 12 18 30 W109 15 02 05 26.7 139.4 -2.8 -44.5 -10 1 4 14800 12 18 30 12 19 30 --- 15 03 05 26.8 139.6 -2.8 -44.3 50 R 1 14000 12 19 30 I1746-321 15 03 05 24.9 142.4 -2.7 -42.7 -10 1 4 14000 12 19 30 12 21 30 --- 15 05 05 25.2 142.8 -2.7 -42.3 110 R 1 12400 12 21 30 W109 15 05 05 27.1 140.0 -2.7 -43.9 -10 1 4 12400 12 21 30 12 22 30 --- 15 06 05 27.3 140.1 -2.7 -43.7 50 R 1 11600 12 22 30 I1746-321 15 06 05 25.3 142.9 -2.7 -42.1 -10 1 4 11600 12 22 30 12 25 00 --- 15 08 36 25.7 143.4 -2.6 -41.6 140 R 1 9600 12 25 00 GC441 15 08 36 28.5 142.3 -2.5 -41.4 -12 1 4 9600 12 25 00 12 26 00 --- 15 09 36 28.7 142.5 -2.5 -41.2 48 R 1 8800 12 26 00 I1746-321 15 09 36 25.8 143.5 -2.6 -41.4 -12 1 4 8800 12 26 00 12 28 00 --- 15 11 36 26.1 143.9 -2.6 -40.9 108 R 1 7200 12 28 00 GC441 15 11 36 28.9 142.9 -2.5 -40.7 -12 1 4 7200 12 28 00 12 29 00 --- 15 12 37 29.1 143.1 -2.5 -40.5 48 R 1 6400 12 29 00 W56 15 12 37 29.2 141.2 -2.6 -42.0 -7 1 4 6400 12 29 00 12 30 00 --- 15 13 37 29.4 141.4 -2.5 -41.8 53 R 1 5600 Schedule for VLBA_MK (Code Mk ) Page 6 IGR J1746-321 ToO UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. TPStart: Tape motion start time. Frequencies are LO sum (band edge). Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) ---------------------------------------------------------------------------------------- --- Tue 8 Apr 2003 Day 98 --- 12 32 00 J1733-1304 15 15 37 42.8 131.4 -2.3 -46.4 87 1 4 5600 12 32 00 12 33 00 --- 15 16 37 43.0 131.6 -2.3 -46.2 60 R 1 4800 12 33 00 I1746-321 15 16 37 26.8 144.8 -2.5 -39.9 -38 1 4 4800 12 33 00 12 35 00 --- 15 18 38 27.1 145.2 -2.5 -39.4 82 R 1 3200 12 35 00 W109 15 18 38 29.1 142.4 -2.5 -41.1 -10 1 4 3200 12 35 00 12 36 00 --- 15 19 38 29.2 142.6 -2.5 -40.8 50 R 1 2400 12 36 00 I1746-321 15 19 38 27.2 145.4 -2.4 -39.2 -10 1 4 2400 12 36 00 12 38 00 --- 15 21 38 27.5 145.7 -2.4 -38.8 110 R 1 800 12 38 00 W109 15 21 38 29.5 143.0 -2.5 -40.4 -10 1 4 800 12 38 00 12 39 00 --- 15 22 38 29.7 143.2 -2.4 -40.2 50 R 1 0 12 39 00 I1746-321 15 22 38 27.6 145.9 -2.4 -38.6 -10 1 5 0 12 39 00 12 41 00 --- 15 24 39 27.9 146.3 -2.4 -38.1 110 F 1 1600 12 41 00 W109 15 24 39 30.0 143.6 -2.4 -39.8 -10 1 5 1600 12 41 00 12 42 00 --- 15 25 39 30.1 143.8 -2.4 -39.5 50 F 1 2400 12 42 00 I1746-321 15 25 39 28.0 146.5 -2.3 -37.9 -10 1 5 2400 12 42 00 12 44 00 --- 15 27 39 28.3 146.9 -2.3 -37.5 110 F 1 4000 12 44 00 W109 15 27 39 30.4 144.2 -2.4 -39.1 -10 1 5 4000 12 44 00 12 45 00 --- 15 28 39 30.5 144.4 -2.3 -38.9 50 F 1 4800 12 45 00 I1746-321 15 28 39 28.4 147.0 -2.3 -37.2 -10 1 5 4800 12 45 00 12 47 00 --- 15 30 40 28.7 147.4 -2.3 -36.8 110 F 1 6400 12 47 00 W109 15 30 40 30.8 144.8 -2.3 -38.4 -10 1 5 6400 12 47 00 12 48 00 --- 15 31 40 30.9 145.0 -2.3 -38.2 50 F 1 7200 12 48 00 I1746-321 15 31 40 28.8 147.6 -2.2 -36.6 -10 1 5 7200 12 48 00 12 50 00 --- 15 33 40 29.0 148.0 -2.2 -36.1 110 F 1 8800 12 50 00 W109 15 33 40 31.2 145.4 -2.3 -37.7 -10 1 5 8800 12 50 00 12 51 00 --- 15 34 40 31.3 145.6 -2.2 -37.5 50 F 1 9600 12 51 00 I1746-321 15 34 40 29.2 148.2 -2.2 -35.9 -10 1 5 9600 12 51 00 12 53 30 --- 15 37 11 29.5 148.7 -2.2 -35.3 140 F 1 11600 Schedule for VLBA_MK (Code Mk ) Page 7 IGR J1746-321 ToO UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. TPStart: Tape motion start time. Frequencies are LO sum (band edge). Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) ---------------------------------------------------------------------------------------- --- Tue 8 Apr 2003 Day 98 --- 12 53 30 GC441 15 37 11 32.4 148.0 -2.1 -35.0 -12 1 5 11600 12 53 30 12 54 30 --- 15 38 11 32.5 148.2 -2.0 -34.7 48 F 1 12400 12 54 30 I1746-321 15 38 11 29.6 148.9 -2.1 -35.1 -12 1 5 12400 12 54 30 12 56 30 --- 15 40 11 29.8 149.3 -2.1 -34.6 108 F 1 14000 12 56 30 GC441 15 40 11 32.7 148.6 -2.0 -34.3 -12 1 5 14000 12 56 30 12 57 30 --- 15 41 11 32.9 148.8 -2.0 -34.0 48 F 1 14800 12 57 30 I1746-321 15 41 11 29.9 149.5 -2.1 -34.4 -12 1 5 14800 12 57 30 12 59 00 --- 15 42 41 30.1 149.8 -2.1 -34.0 78 F 1 16000 12 59 00 W56 15 42 41 33.4 147.3 -2.1 -35.3 -13 1 5 16000 12 59 00 13 00 00 --- 15 43 42 33.5 147.5 -2.0 -35.0 47 F 1 16800 SETUP FILE INFORMATION: NOTE: If DOPPLER, FREQ, or BW were used, see the individual scans for the final BBC settings. Setup file: /users/cwalker/sched/setups/v2cm-256-8-2.set Matches group v2cm_d3 in /users/cwalker/sched/catalogs/freq.dat Fourth 2cm filter Setup group: 1 Station: VLBA Total bit rate: 256 Format: VLBA1:2 Bits per sample: 2 Sample rate: 16.000 Number of channels: 8 Passes/head pos: 1 Speedup factor: 1.00 Tape speeds: Low density - 266.660 ips, High density - 160.00 ips Time per pass for 17600 ft, High density tapes is: 00:22:00 1st LO= 14600.00 14600.00 14600.00 14600.00 14600.00 14600.00 14600.00 14600.00 Net SB= U U U U U U U U Pol. = RCP LCP RCP LCP RCP LCP RCP LCP BBC = 1 2 3 4 5 6 7 8 BBC SB= U U U U U U U U IF = B D B D B D B D VLBA FE= omit 2cm omit 2cm VLBA Synth= 14.6 10.9 10.9 The following frequency sets based on this setup were used. Frequency Set: 1 Setup file default. Used pcal sets: 1 LO sum= 15349.49 15349.49 15357.49 15357.49 15365.49 15365.49 15373.49 15373.49 BBC fr= 749.49 749.49 757.49 757.49 765.49 765.49 773.49 773.49 Bandwd= 8.000 8.000 8.000 8.000 8.000 8.000 8.000 8.000 The following pulse cal sets were used with this setup: Pulse cal detection set: 1 PCAL = 1MHZ PCALXB1= S1 S3 S5 S7 S1 S3 S5 S7 PCALXB2= S2 S4 S6 S8 S2 S4 S6 S8 PCALFR1= 510 510 510 510 6510 6510 6510 6510 PCALFR2= 510 510 510 510 6510 6510 6510 6510 Track assignments are: track1= 2, 10, 18, 26, 3, 11, 19, 27 barrel=roll_auto SOURCE LIST -- IGR J1746-321 ToO Catalog positions marked with *. Precession of date coordinates is based on stop time of first scan. Names used in schedule marked with *. Short names used in VLA and SNAP files marked with +. Observation date used in B1950/J2000 coordinate conversion (PRECDATE): 1979.900 No adjustments are made for rates (DRA, DDEC). Source Source position (RA/Dec) (B1950) (J2000) (Date) * I1746-321 17 42 59.799246 * 17 46 15.607000 17 46 27.723285 -32 12 53.51182 *-32 14 00.70000 -32 14 06.16971 From catalog imbedded in main SCHED input file. * GC441 17 37 43.113166 * 17 40 54.524900 17 41 06.394475 -29 28 19.93553 *-29 29 50.29000 -29 29 58.12492 From catalog imbedded in main SCHED input file. * J1733-1304 17 30 13.535186 * 17 33 02.705784 17 33 13.246165 -13 02 45.83985 *-13 04 49.54833 -13 05 04.87816 From catalog imbedded in main SCHED input file. * W109 17 45 34.736305 * 17 48 45.684100 17 48 57.483620 -29 06 43.28585 *-29 07 39.37400 -29 07 45.19707 From catalog imbedded in main SCHED input file. * W56 17 42 42.769582 * 17 45 52.494900 17 46 04.233452 -28 19 17.62858 *-28 20 26.27000 -28 20 33.14011 From catalog imbedded in main SCHED input file. 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) I1746-321 110.9 GC441 112.3 J1733-1304 114.5 W109 110.6 W56 111.2 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