More VLA Calibrators at Q Band VLA Test Memo #193 Mark Holdaway, Frazer Owen, and Michael Rupen April 20 1995 Abstract: We present 96 compact sources with 90~GHz fluxes above 0.5 Jy which are not in Chandler's VLA Test Memo #192. Most of these sources will make excellent high frequency VLA calibrators. Sources which are bright at 90 GHz are likely to be bright at 43 GHz. We are currently engaged in a project to determine the number of MMA calibrators in the sky at 90 GHz. We have observed many of Alok Patniak's 3000 compact, flat spectrum, extragalactic radio sources with the NRAO 12 m telescope at 90 GHz. (These sources are designated by an "A" next to the source name in the Table below.) At 8 GHz in the A array, these sources typically have only a few percent of their flux in extended emission. At 43 GHz and 90 GHz, the extended emission will be that much weaker. Even though the 90 GHz fluxes were measured with a single dish, we expect these sources to make excellent calibrators. The positional accuracy of Patniak's sources is about 10 mas. Patniak's survey avoided the Galactic plane to select against compact HII regions, which would generally not be useful calibrators for MERLIN. We have also observed a sample of bright, flat spectrum sources in the plane, some of which might be compact HII regions. These are the "maybe" sources, designated by an "M" next to the name. Positions of these sources were taken from the most accurate survey in which they appeared, usually the Texas 365 MHz survey, and positional accuracy is probably a few arcseconds. We have also gathered from the literature a sample of lobe dominated, steep spectrum quasars with bright flat spectrum cores. These are designated by an "S". One potential hazard of using these sources as calibrators is that the 12 m flux may include emission from the extended structure (ie, hotspots). Core positions were taken from tables (when possible) or directly from published maps, and the positional accuracy is on the order of an arcsecond. Katagiri, Morita, and Holdaway have observed 21 of these sources ("A" and "M" sources) with the NMA at 90 GHz, and find similarly high fluxes in a point source component in 20 of the 21 sources. The source which was not a point source to the NMA was an "M" source, likely to be a compact HII region in the galaxy. The most variable source increased in flux by a factor of 3 over 3 months. In the Table below, we present the sources with 90 GHz flux greater than 0.5 Jy which are not presented in Chandler's VLA Test Memo 192. We include the 1950 source name, the 1950 coordinates, a centimeter flux in Jy (taken from Patniak for "A" sources, from the literature for "S" sources, and from various single dish surveys for the "M" sources), our measured 90"GHz flux in Jy, the rms in Jy, and the date of the 90 GHz flux measurement. The flux scale was determined by observations of bright planets, and is accurate to 5-10%. The uncertainties in the flux scale are not included in the rms. We recommend that these sources be added to the VLA calibrator list and observed at other frequencies. While the Patniak sources have positions which are at least as accurate as the VLA calibrators, the "M" and "S" sources will require astrometry prior to entry into the VLA calibrator list. Name Code RA DEC S_cm S_90GHz E_90GHz Date (1950) (1950) (1950) (Jy) (Jy) (Jy) 0002+541 A 00:02:29.056 +54:11:43.178 0.334 0.706 0.093 Oct94 0005+683 A 00:05:54.354 +68:20:40.698 0.103 0.682 0.093 Oct94 0010+405 A 00:10:54.299 +40:34:56.616 0.534 0.723 0.036 Oct93 0012+610 M 00:12:06.9 +61:01:02. 2.034 0.516 0.093 Oct94 0017+200 A 00:17:02.120 +20:05:06.711 1.183 0.546 0.093 Oct94 0237-016 A 02:37:13.717 -02:47:32.852 0.802 0.586 0.139 Feb95 0321+467 A 03:21:51.289 +46:44:34.798 0.302 0.969 0.093 Oct94 0354+231 A 03:54:23.254 +23:11:17.303 0.339 0.711 0.136 Feb95 0433+295 S 04:33:55.210 +29:34:12.6 0.120 0.692 0.046 Oct93 0529+483 A 05:29:27.564 +48:20:47.968 0.539 1.133 0.061 Oct93 0603+476 A 06:03:36.206 +47:40:11.007 0.363 0.953 0.215 Feb95 0616+136 M 06:16:07.3 +13:38:12. 0.927 0.814 0.105 Feb95 0640+090 M 06:40:42.2 +09:00:40.4 0.629 0.525 0.106 Feb95 0650-063 M 06:50:34.2 -06:21:48.3 0.560 0.820 0.105 Feb95 0653-033 M 06:53:41.3 -03:19:09.2 0.607 0.609 0.105 Feb95 0704+293 A 07:04:16.251 +29:22:02.632 0.112 0.535 0.105 Feb95 0749+540 A 07:49:06.444 +54:00:46.414 ? 1.221 0.058 Oct93 0805-060 A 08:05:49.555 -07:42:22.386 1.075 0.967 0.184 Feb95 0842+048 A 08:42:39.205 +04:50:44.688 0.249 0.661 0.185 Feb95 1004+141 A 10:04:59.785 +14:11:10.934 0.942 0.832 0.103 Feb95 1005+066 A 10:05:23.466 +06:36:03.311 0.646 0.526 0.102 Feb95 1015+057 A 10:15:51.238 +05:45:32.819 0.291 0.889 0.102 Feb95 1040+123 S 10:40:06. +12:19:15.1 1.627 0.517 0.062 Oct93 1040+244 A 10:40:25.199 +24:24:19.632 0.664 0.695 0.093 Oct94 1049+215 A 10:49:07.188 +21:35:48.593 1.135 1.092 0.061 Oct93 1100+305 A 11:00:29.718 +30:30:52.591 0.231 0.604 0.093 Oct94 1125+596 A 11:25:23.183 +59:41:46.144 0.538 0.502 0.093 Oct94 1128+385 A 11:28:12.513 +38:31:51.648 0.748 0.544 0.030 Oct93 1200-051 S 12:00:00.430 -05:11:20.4 0.478 0.634 0.079 Oct93 1212+171 A 12:12:31.449 +17:11:18.145 0.395 0.588 0.137 Feb95 1219+044 A 12:19:49.256 +04:29:53.634 1.008 0.555 0.137 Feb95 1222+037 A 12:22:19.098 +03:47:27.086 0.783 0.703 0.137 Feb95 1222+216 A 12:22:23.412 +21:39:23.094 1.055 0.840 0.136 Feb95 1236+049 A 12:36:59.935 +04:59:33.367 0.288 0.563 0.101 Feb95 1302-019 A 13:02:08.717 -03:29:58.542 0.389 0.652 0.101 Feb95 1307+121 A 13:07:04.351 +12:10:22.413 0.785 0.730 0.098 Feb95 1319+220 A 13:19:46.944 +22:03:52.355 0.139 0.577 0.100 Feb95 1324+224 A 13:24:37.118 +22:26:22.704 2.072 1.617 0.100 Feb95 1417+273 A 14:17:45.097 +27:20:09.124 0.326 0.612 0.096 Feb95 1417+385 A 14:17:43.057 +38:35:32.312 0.678 0.616 0.052 Oct93 1423+146 A 14:23:25.458 +14:38:25.976 0.581 0.550 0.097 Feb95 1456+044 A 14:56:29.153 +04:28:09.352 0.587 0.773 0.097 Feb95 1504+377 A 15:04:12.958 +37:42:23.347 1.014 0.688 0.039 Oct93 1505+428 A 15:05:04.056 +42:50:52.743 0.359 0.579 0.025 Oct93 1508-040 A 15:08:14.973 -05:31:48.982 0.694 0.734 0.097 Feb95 1514+004 A 15:14:06.740 +00:26:01.341 0.979 1.034 0.097 Feb95 1514+197 A 15:14:40.988 +19:43:10.983 0.606 0.500 0.098 Feb95 1601+112 A 16:01:19.639 +11:14:00.136 0.357 0.595 0.098 Feb95 1604+159 A 16:04:49.4 +15:59:32.735 0.220 0.562 0.098 Feb95 1623+578 A 16:23:27.709 +57:48:03.967 0.583 0.945 0.224 Feb95 1636+473 A 16:36:19.146 +47:23:28.592 0.704 0.636 0.046 Oct93 1645+410 A 16:45:18.217 +41:04:34.508 0.337 0.512 0.054 Oct93 1656+477 A 16:56:39.602 +47:42:19.649 1.069 0.716 0.047 Oct93 Name Code RA DEC S_cm S_90GHz E_90GHz Date (1950) (1950) (1950) (Jy) (Jy) (Jy) 1700+685 A 17:00:19.666 +68:34:25.169 0.355 0.549 0.093 Oct94 1717+178 A 17:17:00.4 +17:48:09. 0.640 0.642 0.093 Oct94 1726+455 A 17:26:01.201 +45:33:04.556 1.248 0.690 0.058 Oct93 1734+063 A 17:34:47.355 +06:22:48.241 0.544 0.721 0.093 Oct94 1746+469 A 17:46:04.348 +46:59:48.716 0.761 0.525 0.093 Oct94 1747+433 A 17:47:29.598 +43:22:42.568 0.272 0.638 0.093 Oct94 1807+279 A 18:07:13.638 +27:57:35.848 0.327 0.636 0.202 Feb95 1827+062 A 18:27:39.474 +06:17:09.966 0.460 0.738 0.093 Oct94 1849+005 M 18:49:13.7 +00:31:53.8 0.624 0.659 0.093 Oct94 1855+031 M 18:55:32.2 +03:09:11.1 0.722 0.514 0.093 Oct94 1901+319 A 19:01:02.307 +31:55:13.874 1.685 0.808 0.037 Oct93 1929+226 M 19:29:16.9 +22:37:07.7 0.450 0.968 0.093 Oct94 1936-146 A 19:36:36.026 -15:32:38.781 1.078 0.546 0.149 Feb95 1937+630 A 19:37:42.004 +63:00:22.329 0.111 0.731 0.227 Feb95 1944+250 M 19:44:41.3 +25:05:12. 6.163 3.524 0.093 Oct94 1952+138 A 19:52:52.319 +13:50:17.951 0.322 0.524 0.093 Oct94 3C405 S 19:57:44.360 +40:35:46.6 0.327 2.789 0.093 Oct94 1959+330 M 19:59:14.2 +33:02:40. 3.988 1.422 0.093 Oct94 2005+642 A 20:05:42.457 +64:16:01.882 0.851 0.578 0.041 Oct93 2010+463 A 20:10:30.811 +46:19:52.6 0.491 0.597 0.045 Oct93 2013+370 M 20:13:37.1 +37:01:43.9 1.456 3.124 0.093 Oct94 2022+031 A 20:22:38.866 +03:06:55.760 0.375 0.733 0.093 Oct94 2022+204 A 20:22:15.319 +20:26:57.555 0.058 0.649 0.221 Feb95 2023+372 M 20:23:30.9 +37:13:23.9 1.219 0.692 0.093 Oct94 2023-065 A 20:22:59.594 -07:45:42.981 0.534 0.926 0.220 Feb95 2032+117 A 20:32:14.291 +11:44:09.494 0.211 0.633 0.093 Oct94 2043+440 M 20:43:53.6 +44:03:57. 2.246 0.886 0.093 Oct94 2047+181 A 20:47:01.249 +18:10:55.859 0.125 0.830 0.220 Feb95 2049+175 A 20:49:17.427 +17:32:18.472 0.421 0.579 0.093 Oct94 2053-039 A 20:53:12.776 -04:28:18.611 0.243 2.719 0.222 Feb95 2107+353 A 21:07:30.450 +35:20:43.218 0.829 0.814 0.040 Oct93 2247+596 M 22:47:30.3 +59:39:04. 2.258 1.259 0.093 Oct94 2251+134 S 22:51:51.870 +13:25:49.1 0.558 0.717 0.093 Oct94 2251+244 A 22:51:44.396 +24:29:23.998 0.442 0.589 0.093 Oct94 2256+585 M 22:56:36.2 +58:30:57.1 1.338 0.835 0.093 Oct94 2303+599 M 23:03:04.2 +59:58:25. 2.114 1.214 0.093 Oct94 2309+454 A 23:09:28.214 +45:27:37.237 0.543 0.614 0.093 Oct94 2320+506 A 23:20:05.997 +50:41:24.319 1.552 0.738 0.043 Oct93 2327+335 A 23:27:45.966 +33:32:03.589 0.465 0.516 0.093 Oct94 2331+073 A 23:31:40.088 +07:19:52.381 0.966 0.972 0.093 Oct94 2344+092 A 23:44:03.773 +09:14:05.429 1.351 0.526 0.053 Oct93 2346+385 A 23:46:49.833 +38:32:36.957 0.224 0.674 0.055 Oct93 2351+456 A 23:51:49.972 +45:36:22.760 0.831 0.582 0.036 Oct93