COVER INFORMATION Station: WSTRBORK (Code Wb ) Experiment: Parallax Measurement to 1.6GHz OH Masers in OH/IR star OH 138.0+7.4 Exp. Code: EH028A Schedule Version: 4.00 Processed by SCHED version: 11.00 Release of Feb. 15, 2013 PI: Bo HU Address: Max-Planck-Insttitute for Radioastronomy Auf dem Huegel 69 Bonn Germany Phone: +49 228 525180 EMAIL: hubo@mpifr-bonn.mpg.de Fax: Phone during observation: Observing mode: Notes: Phase-cals should BE TURNED OFF at each station Schedule for WSTRBORK (Code Wb ) Page 2 Parallax Measurement to 1.6GHz OH Masers in OH/IR star OH 138.0+7.4 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 27 Oct 2013 Day 300 --- Next scan frequencies: 1609.53 1609.53 1609.53 1609.53 1613.53 1613.53 1613.53 1613.53 1617.53 1617.53 1617.53 1617.53 1621.53 1621.53 1621.53 1621.53 Next BBC frequencies: 119.53 119.53 119.53 119.53 123.53 123.53 123.53 123.53 127.53 127.53 127.53 127.53 131.53 131.53 131.53 131.53 Next scan bandwidths: 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 18 32 39 J0322+6610 21 24 18 46.9 36.2 -6.0 0.0 0 0 18 32 39 18 34 09 --- 21 25 48 47.1 36.3 -6.0 0.0 90 1 18 32 43 18 34 09 OH138.0+7.2 21 25 48 46.5 36.9 -6.0 D 0.0 -15 1 No stop 18 37 39 --- 21 29 18 46.8 37.2 -6.0 0.0 0 5 18 34 13 18 39 39 OH138.0+7.2 21 31 19 47.0 37.3 -5.9 0.0 109 5 18 39 39 18 43 09 --- 21 34 49 47.3 37.6 -5.9 0.0 210 8 18 39 43 18 43 09 J0322+6610 21 34 49 47.9 36.9 -5.8 0.0 -15 8 No stop 18 44 39 --- 21 36 20 48.0 37.0 -5.8 0.0 75 10 18 43 13 18 44 39 OH138.0+7.2 21 36 20 47.5 37.7 -5.8 0.0 -15 10 No stop 18 48 09 --- 21 39 50 47.8 37.9 -5.8 0.0 195 13 18 44 43 18 48 39 J0333+6536 21 40 20 47.1 37.2 -5.9 0.0 10 13 18 48 39 18 50 09 --- 21 41 51 47.2 37.3 -5.9 0.0 90 14 18 48 43 18 50 09 OH138.0+7.2 21 41 51 48.0 38.1 -5.7 0.0 -20 14 No stop 18 53 39 --- 21 45 21 48.3 38.3 -5.7 0.0 190 18 18 50 13 18 53 39 J0322+6610 21 45 21 48.8 37.6 -5.6 0.0 -15 18 No stop 18 55 09 --- 21 46 51 49.0 37.7 -5.6 0.0 75 19 18 53 43 18 55 09 OH138.0+7.2 21 46 51 48.5 38.4 -5.7 0.0 -15 19 No stop 18 58 39 --- 21 50 22 48.8 38.6 -5.6 0.0 195 23 18 55 13 18 59 09 J0333+6536 21 50 52 48.0 38.0 -5.7 0.0 10 23 18 59 09 19 00 39 --- 21 52 22 48.2 38.1 -5.7 0.0 90 24 18 59 13 19 00 39 OH138.0+7.2 21 52 22 49.0 38.7 -5.6 0.0 -20 24 No stop 19 04 09 --- 21 55 53 49.3 39.0 -5.5 0.0 190 27 19 00 43 19 04 09 J0322+6610 21 55 53 49.8 38.2 -5.5 0.0 -15 27 No stop 19 05 39 --- 21 57 23 50.0 38.3 -5.4 0.0 75 29 19 04 13 19 05 39 OH138.0+7.2 21 57 23 49.5 39.1 -5.5 0.0 -15 29 No stop 19 09 09 --- 22 00 54 49.8 39.3 -5.4 0.0 195 32 19 05 43 Schedule for WSTRBORK (Code Wb ) Page 3 Parallax Measurement to 1.6GHz OH Masers in OH/IR star OH 138.0+7.4 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 27 Oct 2013 Day 300 --- 19 09 39 J0333+6536 22 01 24 49.0 38.7 -5.6 0.0 10 32 19 09 39 19 11 09 --- 22 02 54 49.2 38.7 -5.5 0.0 90 34 19 09 43 19 11 09 OH138.0+7.2 22 02 54 50.0 39.4 -5.4 0.0 -20 34 No stop 19 14 39 --- 22 06 25 50.3 39.6 -5.3 0.0 190 37 19 11 13 19 14 39 J0322+6610 22 06 25 50.8 38.8 -5.3 0.0 -15 37 No stop 19 16 09 --- 22 07 55 50.9 38.9 -5.3 0.0 75 38 19 14 43 19 16 09 OH138.0+7.2 22 07 55 50.5 39.7 -5.3 0.0 -15 38 No stop 19 19 39 --- 22 11 25 50.8 39.9 -5.3 0.0 195 42 19 16 13 19 20 09 J0333+6536 22 11 55 50.0 39.3 -5.4 0.0 10 42 19 20 09 19 21 39 --- 22 13 26 50.2 39.4 -5.4 0.0 90 43 19 20 13 19 21 39 OH138.0+7.2 22 13 26 51.0 40.0 -5.2 0.0 -20 43 No stop 19 25 09 --- 22 16 56 51.3 40.2 -5.2 0.0 190 47 19 21 43 19 26 19 F0217+7349 22 18 07 58.2 27.2 -4.0 0.0 0 47 19 26 19 19 31 19 --- 22 23 07 58.5 27.1 -3.9 0.0 300 51 19 26 23 19 32 25 J0322+6610 22 24 14 52.5 39.8 -5.0 0.0 0 51 19 32 25 19 33 55 --- 22 25 44 52.7 39.8 -5.0 0.0 90 53 19 32 29 19 33 55 OH138.0+7.2 22 25 44 52.2 40.7 -5.0 0.0 -15 53 No stop 19 37 25 --- 22 29 15 52.5 40.9 -5.0 0.0 195 56 19 33 59 19 37 55 J0333+6536 22 29 45 51.8 40.3 -5.1 0.0 10 56 19 37 55 19 39 25 --- 22 31 15 51.9 40.4 -5.1 0.0 90 58 19 37 59 19 39 25 OH138.0+7.2 22 31 15 52.7 41.0 -4.9 0.0 -20 58 No stop 19 42 55 --- 22 34 46 53.1 41.1 -4.9 0.0 190 61 19 39 29 19 42 55 J0322+6610 22 34 46 53.5 40.2 -4.8 0.0 -15 61 No stop 19 44 25 --- 22 36 16 53.7 40.3 -4.8 0.0 75 62 19 42 59 19 44 25 OH138.0+7.2 22 36 16 53.2 41.2 -4.8 0.0 -15 62 No stop 19 47 55 --- 22 39 46 53.6 41.4 -4.8 0.0 195 66 19 44 29 19 48 25 J0333+6536 22 40 16 52.8 40.9 -4.9 0.0 10 66 19 48 25 19 49 55 --- 22 41 47 52.9 40.9 -4.9 0.0 90 67 19 48 29 19 49 55 OH138.0+7.2 22 41 47 53.8 41.5 -4.7 0.0 -20 67 No stop 19 53 25 --- 22 45 17 54.1 41.6 -4.7 0.0 190 71 19 49 59 Schedule for WSTRBORK (Code Wb ) Page 4 Parallax Measurement to 1.6GHz OH Masers in OH/IR star OH 138.0+7.4 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 27 Oct 2013 Day 300 --- 19 53 25 J0322+6610 22 45 17 54.6 40.7 -4.6 0.0 -15 71 No stop 19 54 55 --- 22 46 48 54.7 40.7 -4.6 0.0 75 72 19 53 29 19 54 55 OH138.0+7.2 22 46 48 54.3 41.7 -4.7 0.0 -15 72 No stop 19 58 25 --- 22 50 18 54.6 41.8 -4.6 0.0 195 75 19 54 59 19 58 55 J0333+6536 22 50 48 53.8 41.4 -4.7 0.0 10 75 19 58 55 20 00 25 --- 22 52 18 54.0 41.4 -4.7 0.0 90 77 19 58 59 20 00 25 OH138.0+7.2 22 52 18 54.8 41.9 -4.6 0.0 -20 77 No stop 20 03 55 --- 22 55 49 55.2 42.1 -4.5 0.0 190 80 20 00 29 20 03 55 J0322+6610 22 55 49 55.6 41.1 -4.5 0.0 -15 80 No stop 20 05 25 --- 22 57 19 55.7 41.1 -4.4 0.0 75 82 20 03 59 20 05 25 OH138.0+7.2 22 57 19 55.4 42.1 -4.5 0.0 -15 82 No stop 20 08 55 --- 23 00 50 55.7 42.2 -4.4 0.0 195 85 20 05 29 20 09 25 J0333+6536 23 01 20 54.9 41.8 -4.6 0.0 10 85 20 09 25 20 10 55 --- 23 02 50 55.0 41.9 -4.5 0.0 90 86 20 09 29 20 10 55 OH138.0+7.2 23 02 50 55.9 42.3 -4.4 0.0 -20 86 No stop 20 14 25 --- 23 06 21 56.3 42.4 -4.3 0.0 190 90 20 10 59 20 14 25 J0322+6610 23 06 21 56.6 41.4 -4.3 0.0 -15 90 No stop 20 15 55 --- 23 07 51 56.8 41.4 -4.3 0.0 75 91 20 14 29 20 15 55 OH138.0+7.2 23 07 51 56.4 42.5 -4.3 0.0 -15 91 No stop 20 19 25 --- 23 11 22 56.8 42.6 -4.3 0.0 195 95 20 15 59 20 19 55 J0333+6536 23 11 52 55.9 42.2 -4.4 0.0 10 95 20 19 55 20 21 25 --- 23 13 22 56.1 42.2 -4.4 0.0 90 96 20 19 59 20 21 25 OH138.0+7.2 23 13 22 57.0 42.7 -4.2 0.0 -20 96 No stop 20 24 55 --- 23 16 52 57.3 42.8 -4.2 0.0 190 99 20 21 29 20 24 55 J0322+6610 23 16 52 57.7 41.6 -4.1 0.0 -15 99 No stop 20 26 25 --- 23 18 23 57.8 41.7 -4.1 0.0 75 101 20 24 59 20 26 25 OH138.0+7.2 23 18 23 57.5 42.8 -4.1 0.0 -15 101 No stop 20 29 55 --- 23 21 53 57.9 42.9 -4.1 0.0 195 104 20 26 29 20 30 25 J0333+6536 23 22 23 57.0 42.5 -4.2 0.0 10 104 20 30 25 20 31 55 --- 23 23 54 57.2 42.6 -4.2 0.0 90 106 20 30 29 Schedule for WSTRBORK (Code Wb ) Page 5 Parallax Measurement to 1.6GHz OH Masers in OH/IR star OH 138.0+7.4 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 27 Oct 2013 Day 300 --- 20 31 55 OH138.0+7.2 23 23 54 58.1 42.9 -4.0 0.0 -20 106 No stop 20 35 25 --- 23 27 24 58.4 43.0 -4.0 0.0 190 109 20 31 59 20 35 25 J0322+6610 23 27 24 58.7 41.8 -3.9 0.0 -15 109 No stop 20 36 55 --- 23 28 54 58.9 41.8 -3.9 0.0 75 110 20 35 29 20 36 55 OH138.0+7.2 23 28 54 58.6 43.0 -4.0 0.0 -15 110 No stop 20 40 25 --- 23 32 25 58.9 43.1 -3.9 0.0 195 114 20 36 59 20 40 55 J0333+6536 23 32 55 58.1 42.8 -4.0 0.0 10 114 20 40 55 20 42 25 --- 23 34 25 58.2 42.8 -4.0 0.0 90 115 20 40 59 20 42 25 OH138.0+7.2 23 34 25 59.1 43.1 -3.9 0.0 -20 115 No stop 20 45 55 --- 23 37 56 59.5 43.2 -3.8 0.0 190 119 20 42 29 20 45 55 J0322+6610 23 37 56 59.8 41.9 -3.8 0.0 -15 119 No stop 20 47 25 --- 23 39 26 60.0 41.9 -3.7 0.0 75 120 20 45 59 20 47 25 OH138.0+7.2 23 39 26 59.7 43.2 -3.8 0.0 -15 120 No stop 20 50 55 --- 23 42 57 60.0 43.2 -3.7 0.0 195 123 20 47 29 20 51 25 J0333+6536 23 43 27 59.2 43.0 -3.9 0.0 10 123 20 51 25 20 52 55 --- 23 44 57 59.3 43.0 -3.8 0.0 90 125 20 51 29 20 52 55 OH138.0+7.2 23 44 57 60.2 43.2 -3.7 0.0 -20 125 No stop 20 56 25 --- 23 48 28 60.6 43.3 -3.6 0.0 190 128 20 52 59 20 56 25 J0322+6610 23 48 28 60.9 42.0 -3.6 0.0 -15 128 No stop 20 57 55 --- 23 49 58 61.0 42.0 -3.6 0.0 75 130 20 56 29 20 57 55 OH138.0+7.2 23 49 58 60.7 43.3 -3.6 0.0 -15 130 No stop 21 01 25 --- 23 53 28 61.1 43.3 -3.5 0.0 195 133 20 57 59 21 01 55 J0333+6536 23 53 59 60.3 43.1 -3.7 0.0 10 133 21 01 55 21 03 25 --- 23 55 29 60.4 43.1 -3.7 0.0 90 134 21 01 59 21 03 25 OH138.0+7.2 23 55 29 61.3 43.3 -3.5 0.0 -20 134 No stop 21 06 55 --- 23 58 59 61.7 43.3 -3.5 0.0 190 138 21 03 29 21 06 55 J0322+6610 23 58 59 61.9 41.9 -3.4 0.0 -15 138 No stop 21 08 25 --- 00 00 30 62.1 41.9 -3.4 0.0 75 139 21 06 59 21 08 25 OH138.0+7.2 00 00 30 61.8 43.3 -3.4 0.0 -15 139 No stop 21 11 55 --- 00 04 00 62.2 43.2 -3.4 0.0 195 143 21 08 29 Schedule for WSTRBORK (Code Wb ) Page 6 Parallax Measurement to 1.6GHz OH Masers in OH/IR star OH 138.0+7.4 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 27 Oct 2013 Day 300 --- 21 12 25 J0333+6536 00 04 30 61.3 43.1 -3.5 0.0 10 143 21 12 25 21 13 55 --- 00 06 00 61.5 43.1 -3.5 0.0 90 144 21 12 29 21 13 55 OH138.0+7.2 00 06 00 62.4 43.2 -3.3 0.0 -20 144 No stop 21 17 25 --- 00 09 31 62.8 43.2 -3.3 0.0 190 147 21 13 59 21 17 25 J0322+6610 00 09 31 63.0 41.7 -3.2 0.0 -15 147 No stop 21 18 55 --- 00 11 01 63.1 41.7 -3.2 0.0 75 149 21 17 29 21 18 55 OH138.0+7.2 00 11 01 62.9 43.2 -3.3 0.0 -15 149 No stop 21 22 25 --- 00 14 32 63.3 43.1 -3.2 0.0 195 152 21 18 59 21 22 55 J0333+6536 00 15 02 62.4 43.0 -3.3 0.0 10 152 21 22 55 21 24 25 --- 00 16 32 62.6 43.0 -3.3 0.0 90 154 21 22 59 21 24 25 OH138.0+7.2 00 16 32 63.5 43.0 -3.2 0.0 -20 154 No stop 21 27 55 --- 00 20 03 63.9 43.0 -3.1 0.0 190 157 21 24 29 21 27 55 J0322+6610 00 20 03 64.0 41.4 -3.1 0.0 -15 157 No stop 21 29 25 --- 00 21 33 64.2 41.4 -3.0 0.0 75 158 21 27 59 21 29 25 OH138.0+7.2 00 21 33 64.0 42.9 -3.1 0.0 -15 158 No stop 21 32 55 --- 00 25 04 64.4 42.8 -3.0 0.0 195 162 21 29 29 21 33 25 J0333+6536 00 25 34 63.5 42.9 -3.2 0.0 10 162 21 33 25 21 34 55 --- 00 27 04 63.7 42.8 -3.1 0.0 90 163 21 33 29 21 34 55 OH138.0+7.2 00 27 04 64.6 42.8 -3.0 0.0 -20 163 No stop 21 38 25 --- 00 30 35 64.9 42.6 -2.9 0.0 190 167 21 34 59 21 40 51 F0102+5824 00 33 01 83.0 34.7 -0.5 0.0 12 167 21 40 51 21 45 51 --- 00 38 01 83.4 30.4 -0.4 0.0 300 171 21 40 55 SETUP FILE INFORMATION: NOTE: If DOPPLER, FREQ, or BW were used, see the individual scans for the final BBC settings. ======== Setup file: sess313.L128 --- WARNING --- This group does not match an entry in the frequency catalog. This might be ok because the catalog is not complete. But be very careful to be sure that the setup is correct. Setup group: 12 Station: WSTRBORK Total bit rate: 128 Format: MKIV1:1 Bits per sample: 2 Sample rate: 4.000 Number of channels: 16 DBE type: Speedup factor: 2.00 Disk used to record data. 1st LO= 1490.00 1490.00 1490.00 1490.00 1490.00 1490.00 1490.00 1490.00 1490.00 1490.00 1490.00 1490.00 1490.00 1490.00 1490.00 1490.00 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 = 2 1 2 1 4 3 4 3 6 5 6 5 8 7 8 7 BBC SB= L L U U L L U U L L U U L L U U IF = 2N 1N 2N 1N 2N 1N 2N 1N 2N 1N 2N 1N 2N 1N 2N 1N The following frequency sets based on these setups were used. Frequency Set: 12 Based on FREQ, BW, and/or DOPPLER in schedule. LO sum= 1609.53 1609.53 1609.53 1609.53 1613.53 1613.53 1613.53 1613.53 1617.53 1617.53 1617.53 1617.53 1621.53 1621.53 1621.53 1621.53 BBC fr= 119.53 119.53 119.53 119.53 123.53 123.53 123.53 123.53 127.53 127.53 127.53 127.53 131.53 131.53 131.53 131.53 Bandwd= 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 Matching frequency sets: 12 Track assignments are: track1= 2, 6, 10, 14, 18, 22, 26, 30, 3, 7, 11, 15, 19, 23, 27, 31 barrel=roll_off POSITIONS OF SOURCES USED IN RECORDING SCANS Source Source position (RA/Dec) Error (B1950) (J2000) (Date) (mas) * 3C84 03 16 29.567270 * 03 19 48.160100 03 20 45.921944 0.00 41 19 51.91597 * 41 30 42.10310 41 33 39.09523 0.00 From catalog imbedded in main SCHED input file. Doppler based on other sources. * F0217+7349 02 12 49.921919 * 02 17 30.813400 02 18 56.593029 0.00 73 35 40.08567 * 73 49 32.62200 73 53 22.67842 0.00 From catalog imbedded in main SCHED input file. Doppler based on other sources. * F0102+5824 00 59 43.470991 * 01 02 45.762400 01 03 40.192062 0.00 58 08 04.84785 * 58 24 11.13700 58 28 49.03177 0.00 From catalog imbedded in main SCHED input file. Doppler based on other sources. * J0322+6610 03 17 57.999024 * 03 22 27.228812 03 23 47.000472 0.00 65 59 45.07766 * 66 10 28.30547 66 13 18.97213 0.00 From catalog imbedded in main SCHED input file. Doppler based on other sources. * J0333+6536 03 29 25.878099 * 03 33 56.737993 03 35 16.760545 0.00 65 26 52.21323 * 65 36 56.18412 65 39 34.72130 0.00 From catalog imbedded in main SCHED input file. Doppler based on other sources. * OH138.0+7.2 03 20 41.852264 * 03 25 08.800001 03 26 27.789924 0.00 65 21 32.90423 * 65 32 07.00001 65 34 54.93914 0.00 From catalog imbedded in main SCHED input file. Doppler based on LSR frame and radio definition. Velocities: -40.00 -40.00 -40.00 -40.00 -40.00 -40.00 -40.00 -40.00 -40.00 -40.00 -40.00 -40.00 -40.00 -40.00 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. Source Setup file Frequency sets Observing hours (duplicates not shown) Scan Baseline 3C84 sess313.L128 1 2 3 4 5 6 7 8 9 0.083 4.583 F0217+7349 sess313.L128 1 2 3 4 5 6 7 8 9 12 0.083 5.500 F0102+5824 sess313.L128 1 2 3 4 5 6 7 8 9 12 0.083 4.583 J0322+6610 sess313.L128 1 2 3 4 5 6 7 8 9 12 0.600 29.063 J0333+6536 sess313.L128 1 2 3 4 5 6 7 8 9 12 0.600 34.200 OH138.0+7.2sess313.L128 1 2 3 4 5 6 7 8 9 12 2.800 162.001 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) 3C84 147.5 F0217+7349 119.1 F0102+5824 132.9 J0322+6610 125.3 J0333+6536 125.4 OH138.0+7.2 125.8 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