S-band gain calibrators
Below are the current lists of MeerKAT S-band gain calibrators, chosen from the existing MeerKAT L-band list (Table 1) and new MeerKAT S-band gain calibrators chosen from ATCA and VLA calibrator lists (Table 2).
Some sources have been excluded due to evidence of extended structure.
Sources in Table 1 were observed at the S4 sub-band (2625 MHz to 3500 MHz). Each source was observed over several 7.5-minute scans scattered over a period of a few hours. The selection analysis is documented in memos, which will be made available soon.
Sources in Table 2 were observed at the S3 sub-band (2406 MHz to 3281 MHz). The selection analysis is documented in a soon to be released memo.
The list below is subject to change as we will add more calibrators soon. The primary selection of calibrators is based on an image flux and closure quantities analysis, viz:
Closure phases must be less than 5 degrees.
Closure amplitudes must be unity with a one-sigma error.
Stokes I flux density must be at least 1 Jy/beam at the centre of the band.
Stokes I signal-to-noise ratio must be at least 10 at the centre of the band. The Stokes error is estimated by the mean of the standard deviations of the flux at the phase centre of the target field at 10 frequency channels near the centre of the band. These values were found to be similar to the root-mean-square (RMS) error.
All secondary sources in the field must not be brighter than 10% of the peak flux of the field target source.
A source must not have a resolved fraction, , that is significantly larger than unity.
A source must have no detectable sub-structure in UV-distance space (amplitude vs baseline).
Table 1: MeerKAT S-band gain calibrators, chosen from the existing MeerKAT L-band list.
Calibrator Name
| RAJ2000 | DECJ2000 | Flux Density (2.877 - 2.962GHz) / Jy | Flux Density Error (2.877 - 2.962GHz) / Jy | Mean Closure Amplitude / percentage | Mean Closure Phase / deg | |
|---|---|---|---|---|---|---|---|
| 1 | J0010-4153 | 0008-421 | 00:10:53 | -41:53:11 | 2.63400 | 0.00830 | 1.00470 | -0.02320 |
| 2 | J0022+0014 | 0019-000 | 00:22:25 | +00:14:56.163 | 2.00370 | 0.00630 | 1.01300 | -0.01100 |
| 3 | J0024-4202 | 0022-423 | 00:24:43 | -42:02:04 | 3.21400 | 0.01170 | 1.00650 | 0.07080 |
| 4 | J0025-2602 | 0023-263 | 00:25:49 | -26:02:13 | 6.15400 | 0.02070 | 1.01130 | -0.02430 |
| 5 | J0059+0006 | 0056-001 | 00:59:06 | +00:06:51.621 | 2.06530 | 0.01000 | 1.01950 | -0.25410 |
| 6 | J0108+0134 | 0106+013 | 01:08:39 | +01:35:0.317 | 4.85730 | 0.06230 | 1.05250 | 0.96060 |
| 7 | J0137+3309 | 3C48 | 01:37:41 | +33:09:35.134 | 10.26100 | 0.10500 | 1.00710 | 0.00930 |
| 8 | J0155-4048 | 0153-410 | 01:55:37 | -40:48:42 | 1.82370 | 0.00500 | 1.01280 | 0.04050 |
| 9 | J0203-4349 | 0201-440 | 02:03:41 | -43:49:51 | 1.79900 | 0.01970 | 1.17660 | 0.57890 |
| 10 | J0210-5101 | 0208-512 | 02:10:46 | -51:01:02 | 3.32970 | 0.03230 | 1.05100 | 0.90690 |
| 11 | J0238+1636 | 0235+164 | 02:38:39 | +16:36:59.275 | 2.10870 | 0.00600 | 1.00910 | -0.00430 |
| 12 | J0240-2309 | 0237-233 | 02:40:08 | -23:09:16 | 5.30030 | 0.05300 | 1.00200 | 0.04570 |
| 13 | J0252-7104 | 0252-712 | 02:52:46 | -71:04:35 | 3.32230 | 0.01170 | 1.00430 | -0.01600 |
| 14 | J0303-6211 | 0302-623 | 03:03:51 | -62:11:26 | 2.61970 | 0.01870 | 1.00580 | 0.17570 |
| 15 | J0318+1628 | CTA21 | 03:18:58 | +16:28:32.678 | 5.32870 | 0.02600 | 1.00270 | -0.03740 |
| 16 | J0323+0534 | 0320+053 | 03:23:20 | +05:34:11.891 | 1.65270 | 0.00400 | 1.01310 | -0.00160 |
| 17 | J0403+2600 | 0400+258 | 04:03:06 | +26:00:1.503 | 1.30300 | 0.00570 | 1.00780 | -0.05950 |
| 18 | J0405-1308 | 0403-132 | 04:05:34 | -13:08:14 | 3.42330 | 0.02700 | 1.07120 | -0.08750 |
| 19 | J0409-1757 | 0406-180 | 04:09:07 | -17:57:10 | 1.43770 | 0.00200 | 1.01970 | -0.00840 |
| 20 | J0420-6223 | 0420-625 | 04:20:56 | -62:23:39 | 1.88200 | 0.00470 | 1.04120 | 0.05620 |
| 21 | J0423-0120 | 0420-014 | 04:23:16 | -01:20:33 | 3.07670 | 0.01000 | 1.00720 | 0.08910 |
| 22 | J0431+2037 | 0428+205 | 04:31:04 | +20:37:34.265 | 3.61770 | 0.00900 | 1.00190 | -0.04520 |
| 23 | J0440-4333 | 0438-436 | 04:40:17 | -43:33:09 | 2.87770 | 0.01970 | 1.03610 | 0.07700 |
| 24 | J0453-2807 | 0451-282 | 04:53:15 | -28:07:37 | 1.84800 | 0.01070 | 1.02710 | -0.48980 |
| 25 | J0503+0203 | 0500+019 | 05:03:21 | +02:03:4.677 | 2.73470 | 0.00970 | 1.00440 | -0.03030 |
| 26 | J0521+1638 | 3C138 | 05:21:10 | +16:38:22.052 | 6.38630 | 0.13600 | 1.01720 | 0.24070 |
| 27 | J0534+1927 | 0531+194 | 05:34:45 | +19:27:21.486 | 4.18300 | 0.02870 | 1.01210 | 0.14820 |
| 28 | J0538-4405 | 0537-441 | 05:38:50 | -44:05:09 | 3.45270 | 0.01800 | 1.01690 | 0.01520 |
| 29 | J0609-1542 | 0607-157 | 06:09:41 | -15:42:41 | 4.16170 | 0.01970 | 1.00280 | 0.10070 |
| 30 | J0616-3456 | 0614-349 | 06:16:36 | -34:56:17 | 2.30870 | 0.00430 | 1.01560 | 0.02220 |
| 31 | J0632+1022 | 0629+104 | 06:32:15 | +10:22:1.676 | 1.62800 | 0.01530 | 1.01440 | -0.02890 |
| 32 | J0725-0054 | 0723-008 | 07:25:51 | -00:54:57 | 7.53330 | 0.06300 | 1.00790 | 0.11160 |
| 33 | J0730-1141 | 0727-115 | 07:30:19 | -11:41:13 | 3.42470 | 0.01530 | 1.00810 | -0.02160 |
| 34 | J0735-1735 | 0733-174 | 07:35:46 | -17:35:49 | 2.33130 | 0.00870 | 1.00670 | 0.12160 |
| 35 | J0739+0137 | 0736+017 | 07:39:18 | +01:37:4.618 | 1.53170 | 0.00670 | 1.01820 | -0.01160 |
| 36 | J0745+1011 | 0742+103 | 07:45:33 | +10:11:12.692 | 4.15870 | 0.01670 | 1.00160 | 0.06950 |
| 37 | J0828-3731 | 0826-373 | 08:28:05 | -37:31:06 | 2.33570 | 0.00670 | 1.00280 | 0.00510 |
| 38 | J0854+2006 | OJ287 | 08:54:49 | +20:06:30.641 | 5.09330 | 0.05170 | 1.00500 | -0.01100 |
| 39 | J1008+0730 | 3C237 | 10:08:00 | +07:30:16.552 | 3.88430 | 0.05300 | 1.12080 | -0.30150 |
| 40 | J1058+0133 | 1055+018 | 10:58:30 | +01:33:58.824 | 4.28700 | 0.03700 | 1.01190 | 0.32940 |
| 41 | J1609+2641 | CTD93 | 16:09:13 | +26:41:29.036 | 3.03600 | 0.00300 | 1.00400 | 0.41180 |
| 42 | J1733-1304 | NRAO530 | 17:33:03 | -13:04:50 | 5.46000 | 0.03900 | 1.03180 | 0.48560 |
| 43 |