Jonckheere Double Star Photometry Part III: Lyra, Equuleus, and Eridanus

Page 351 Jonckheere Double Star Photometry Part III: Lyra, Equuleus, and Eridanus Wilfried R.A. Knapp Vienna, Austria wilfried.knapp@gmail.com Abstract: If any double star discoverer is in urgent need of photometry then it is Jonckheere. There are over 3000 Jonckheere objects listed in the WDS catalog and a good part of them have magnitudes which are obviously far too bright. To keep the workload manageable only one image per object is taken and photometry is done with a software allowing a simple point and click procedure even a single measurement is better than the currently usually given estimation. 1. Introduction As follow up to the first two reports on J-objects in Cygnus (Knapp; Nanson 2016) and Delphinus (Knapp 2016) I selected for this report all J-objects in Lyra (Lyr), Equuleus (Equ), and Eridanus (Eri) given in the Tables 1 to 3 with all values based on WDS data as of April 2015. 2. Measurements 2.1 Photometry for the J-objects in Lyra For each of the listed J-objects one single image was taken (in Bessel epoch 2015.713) with itelescope it24 with 3 second exposure time. The initial plate solving was done by AAVSO VPhot and in the few cases with negative VPhot result again but positive with MaxIm DL6/PinPoint. Each image was then once more plate solved with Astrometrica using the UCAC4 catalog with reference stars in the Vmag range of 10.5 to 14.5 giving not only RA/Dec coordinates but also photometry results for all reference stars used including an average dvmag error. The J-objects were then located in the center of the image (worked fine with few exceptions indicating that the given RA/Dec coordinates are usually correct with the exceptions suggesting position problems) and photometry was then done using the Astrometrica procedure with point and click at the components delivering Vmag measurements based on all reference stars used for plate solving. The only changing parameter was the aperture radius used for photometry aiming to keep it equal or at least near 1.5x FWHM. In cases with smaller separation the star disks touched or overlapped but allowed nevertheless individual photometry even if less reliable than with clear separated disks. J110 allowed only the measurement of the combined magnitude but even in this case it is then possible to make a well-founded estimation for the components based on the initial observed m between the components based on the formula m combined 10 m 2.5log 2.521 2.521 m 1` 2 according to Greaney 2012. Measurements of the J-objects in Lyra are given in Table 4. 2.2 Photometry and Astrometry for the J-objects in Equ Beginning with the J-objects in Equ, I decided to provide photometric results and astrometric measurements in the form of RA/Dec coordinates resulting from plate solving as well as separation and position angle calculated based on the RA/Dec coordinates of the components. This is done by using the spherical trigonometry formulas provided by Buchheim 2008. Measurements of the J-objects in Equ are given in Table 5. 2.3 Photometry and Astrometry for the J-objects in Eri In Table 6, I again report photometric results and astrometric measurements in the form of RA/Dec coordinates resulting from plate solving as well as separation and position angle calculated based on the RA/Dec coordinates of the components. This is done by using the spherical trigonometry formulas provided by Buchheim 2008. Table 6 gives the measurements of the J-objects in Eri. (Continued on page 360)

Page 352 Table 1: WDS April 2015 values for the Jonckheere objects in Lyra sorted by designation number WDS ID Name RA Dec Sep M1 M2 PA 18511+3524 J110 AB 18:51:06.099 +35:24:14.095 2.0 10.47 11.81 174 19018+3337 J112 AB 19:01:48.373 +33:37:16.501 25.4 6.39 13.30 178 18497+3223 J131 AB 18:49:41.470 +32:23:14.701 2.7 10.77 13.00 179 18386+2937 J525 AB 18:38:31.427 +29:37:06.997 3.1 9.20 9.40 69 18225+3130 J760 AB 18:22:28.757 +31:30:17.400 2.4 9.50 13.00 212 18274+3137 J761 AB 18:27:19.009 +31:36:35.803 3.7 9.60 11.20 180 18300+4033 J762 AB 18:30:01.387 +40:34:18.206 3.9 10.00 12.50 249 18301+4325 J763 AB 18:30:09.647 +43:26:30.106 1.8 9.70 9.70 309 18349+4053 J764 AB 18:34:53.410 +40:54:10.099 2.8 12.56 13.70 201 18494+3324 J765 AB 18:49:11.951 +33:25:51.105 2.3 12.30 12.50 333 19030+3729 J766 AB 19:02:56.942 +37:27:53.300 3.0 10.80 11.40 2 19030+3729 J766 AC 19:02:56.942 +37:27:53.300 16.7 10.80 12.10 176 19064+3750 J767 AB 19:06:29.987 +37:49:27.503 3.0 10.51 12.00 1 19064+3750 J767 AC 19:06:29.987 +37:49:27.503 7.9 10.51 13.00 181 19131+2946 J768 AB 19:13:05.571 +29:46:56.798 2.9 10.50 12.20 350 19203+2914 J769 AB 19:20:15.527 +29:12:01.500 3.7 9.70 9.90 207 19031+2757 J811 AB 19:03:08.340 +27:56:44.903 2.6 11.90 12.40 248 18381+3000 J1138 AB 18:38:00.693 +30:00:38.802 2.7 9.80 9.80 300 19075+2728 J1205 AB 19:07:25.667 +27:28:39.202 3.5 10.00 10.20 317 19117+2712 J1206 AB 19:11:37.632 +27:12:44.703 3.0 11.94 12.20 332 18491+2834 J1208 AB 18:49:09.932 +28:34:17.499 5.0 9.50 10.00 333 19045+3406 J1209 AB 19:04:25.079 +34:06:19.893 4.6 9.50 10.00 155 19115+2953 J1263 AB 19:11:31.418 +29:53:24.602 31.1 7.62 13.00 255 19115+2953 J1263 BC 19:11:28.699 +29:53:10.203 8.0 13.00 14.10 42 19047+2850 J2941 AB 19:04:46.441 +28:51:04.499 8.6 10.80 12.50 234 19056+2848 J2942 AB 19:05:40.549 +28:49:42.802 6.8 11.80 13.00 60 19079+3043 J2945 AC 19:07:48.567 +30:43:36.202 9.8 10.81 14.10 192 19068+3815 J3213 AB 19:06:51.500 +38:15:42.105 2.5 9.70 9.70 201 19145+2945 J3313 AB 19:14:31.738 +29:45:13.898 10.7 8.94 14.00 32

Page 353 Table 2: WDS April 2015 values for the Jonckheere objects in Equuleus sorted by designation number WDS ID Name RA Dec Sep M1 M2 PA 21021+1016 J158 AB 21:02:08.863 +10:17:33.400 5.0 10.93 13.10 166 21086+0938 J159 AB 21:08:35.231 +09:37:46.301 4.0 10.30 11.30 247 21225+1057 J161 AB 21:22:28.071 +10:57:18.401 2.0 10.45 10.66 299 21124+0745 J576 AB 21:12:25.450 +07:45:06.101 2.3 10.10 10.60 236 20595+1113 J608 AB 20:59:27.721 +11:13:22.301 5.0 11.20 13.50 105 21091+0429 J848 AB 21:09:07.730 +04:28:57.100 2.6 10.23 13.00 145 20592+1129 J913 AB 20:59:09.882 +11:28:41.001 2.9 9.20 10.90 120 21242+0248 J914 AB 21:24:11.060 +02:46:59.600 1.9 11.11 11.11 0 21256+0248 J1039 AB 21:25:37.509 +02:47:43.900 4.3 9.60 10.50 332 21224+0953 J1356 AB 21:22:26.478 +09:52:36.200 7.7 12.00 12.40 178 21192+0339 J1721 AB 21:19:20.568 +03:40:56.800 3.8 11.10 13.80 275 21066+1137 J1781 AB 21:06:38.907 +11:36:55.802 7.8 9.40 11.00 117 21197+0537 J2341 AB 21:19:43.111 +05:37:11.900 7.3 11.90 11.90 349 21071+1042 J2576 AB 21:06:55.702 +10:29:50.099 6.1 12.00 13.00 59 21222+1114 J2605 AB 21:22:21.451 +11:13:50.800 1.9 11.55 13.30 222 Table 3: WDS April 2015 values for the Jonckheere objects in Eridanus sorted by designation number WDS ID Name RA Dec Sep M1 M2 PA 04531-1039 J318 AB 04:53:10.249-10:39:16.900 4.8 12.44 12.60 286 05043-0514 J319 AB 05:04:21.341-05:12:59.700 3.3 11.05 12.10 233 04234-0634 J708 AB 04:23:23.471-06:34:15.400 2.2 10.84 11.13 282 04297-0335 J709 AB 04:29:42.339-03:34:40.600 1.2 10.72 10.86 87 04383-0243 J710 AB 04:38:19.390-02:42:55.900 3.2 10.50 11.70 315 04584-0908 J1003 AB 04:58:26.311-09:06:00.101 5.4 11.36 13.60 238 05088-0830 J1004 AB 05:08:49.960-08:30:58.801 3.3 12.52 12.50 322 04302-0337 J1087 AB 04:30:12.760-03:37:12.900 2.6 11.06 15.10 13 02475-0601 J1245 AB 02:47:29.960-06:00:51.801 2.3 11.00 11.04 12 02501-0616 J1453 AB 02:50:07.000-06:16:11.900 9.2 11.10 10.70 201 02501-0616 J1453 AC 02:50:07.000-06:16:11.900 38.5 11.13 13.00 69 03032-0215 J1455 AB 03:03:07.460-02:14:53.700 6.2 11.50 11.80 61 03175-1222 J1456 AB 03:17:30.390-12:22:51.801 3.6 11.06 11.16 319 03361-0320 J1457 AB 03:36:04.420-03:20:05.800 2.9 10.34 10.84 216 04220-0626 J1459 AB 04:21:59.820-06:25:33.901 3.0 11.03 11.10 241

Page 354 Table 4. Bessel epoch 2015.713 photometry results for the J objects in Lyr. M1 WDS and M2 WDS are the WDS catalog values. M1 new stands for measured M1, dm1 stands for delta between M1 WDS and M1 new. M2 new stands for measured M2, dm2 stands for delta M1 WDS and M1 new. Err M1 stands for the estimated error range calculated from the average delta Vmag over all reference stars used in the image and the SNR value of the star with the formula SQRT(dVmag^2+(2.5*LOG10(1+1/SNR))^2 WDS ID Name M1 WDS M1 new dm1 Err M1 M2 WDS M2 new dm2 Err M2 Notes 18511+3524 J110 AB 10.47 10.710-0.240 0.130 11.81 12.050-0.240 0.130 disks - no separate photometry possible. Combined magnitude 10.436 with SNR 132.41 gives estimated M1 new and M2 new values confirming rather well the current WDS values 19018+3337 J112 AB 6.39 6.504-0.114 0.180 13.30 12.582 0.718 A too bright for reliable photometry 0.182 No resolution of B 18497+3223 J131 AB 10.77 10.767 0.003 0.150 13.00 - - - suggests B being far fainter than listed 18386+2937 J525 AB 9.20 11.162-1.962 0.141 9.40 11.342-1.942 0.141 18225+3130 J760 AB 9.50 11.524-2.024 0.130 13.00 12.914 0.086 0.133 18274+3137 J761 AB 9.60 11.211-1.611 0.140 11.20 12.801-1.601 0.143 18300+4033 J762 AB 10.00 12.404-2.404 0.082 12.50 13.643-1.143 0.090 18301+4325 J763 AB 9.70 11.975-2.275 0.076 9.70 12.250-2.550 0.081 Touching/Overlapping star disks 18349+4053 J764 AB 12.56 11.751 0.809 0.052 13.70 12.395 1.305 0.055 18494+3324 J765 AB 12.30 11.385 0.915 0.160 12.50 11.408 1.092 0.160 Touching star disks 19030+3729 J766 AB 10.80 11.718-0.918 0.131 11.40 12.425-1.025 0.131 Touching star disks 19030+3729 J766 AC 10.80 11.718-0.918 0.131 12.10 12.780-0.680 0.132 19064+3750 J767 AB 10.51 11.587-1.077 0.141 12.00 13.140-1.140 0.146 19064+3750 J767 AC 10.51 11.587-1.077 0.141 13.00 13.994-0.994 0.150 19131+2946 J768 AB 10.50 12.356-1.856 0.152 12.20 14.681-2.481 0.174 SNR for B <20 19203+2914 J769 AB 9.70 11.603-1.903 0.160 9.90 12.185-2.285 0.161 19031+2757 J811 AB 11.90 11.699 0.201 0.151 12.40 12.973-0.573 Touching star disks. 0.164 SNR for B <20 18381+3000 J1138 AB 9.80 11.910-2.110 0.102 9.80 12.011-2.211 0.102 Touching star disks 19075+2728 J1205 AB 10.00 12.094-2.094 0.161 10.20 12.250-2.050 0.162 19117+2712 J1206 AB 11.94 13.373-1.433 0.174 12.20 13.479-1.279 0.175 18491+2834 J1208 AB 9.50 11.538-2.038 0.131 10.00 12.051-2.051 0.131 19045+3406 J1209 AB 9.50 11.529-2.029 0.190 10.00 12.303-2.303 0.191 No double star at this position. Nearby A 19 11 46.012 +27 12 02.68 and B 19 11 45.900 +27 12 04.86 with dra 0.14 and ddec 0.15 giving Sep 2.643" with Err 0.205 and PA 325.573 with Err 4.439 Minor position issue: A 18 49 14.783 +28 34 46.97 18 49 14.627 +28 34 51.17 with dra 0.14 and ddec 0.15 giving Sep 4.676" with Err 0.205 and PA 333.930 with Err 2.413 Table 4 concludes on next page.

Page 355 Table 4 (conclusion). Bessel epoch 2015.713 photometry results for the J objects in Lyr. M1 WDS and M2 WDS are the WDS catalog values. M1 new stands for measured M1, dm1 stands for delta between M1 WDS and M1 new. M2 new stands for measured M2, dm2 stands for delta M1 WDS and M1 new. Err M1 stands for the estimated error range calculated from the average delta Vmag over all reference stars used in the image and the SNR value of the star with the formula SQRT(dVmag^2+(2.5*LOG10(1+1/SNR))^2 WDS ID Name M1 WDS M1 new dm1 Err M1 M2 WDS M2 new dm2 Err M2 Notes 19115+2953 J1263 AB 7.62 7.466 0.154 0.140 13.00 12.917 0.083 0.142 A too bright for reliable measurement, star disk looks elongated, might be a close double itself 19115+2953 J1263 BC 13.00 12.917 0.083 0.142 14.10 14.040 0.060 0.151 SNR for C <20 19047+2850 J2941 AB 10.80 12.361-1.561 0.141 12.50 14.402-1.902 0.150 SNR for B <20 19056+2848 J2942 AB 11.80 13.155-1.355 0.152 13.00 14.433-1.433 0.165 SNR for B <20 19079+3043 J2945 AC 10.81 10.616 0.194 0.150 14.10 13.685 0.415 Mag for HLM16 B measured with 12.340 with 0.156 SNR 51.98 (WDS lists 12.7mag) Notes regarding the notes column: Touching star disks indicates that the rims of the star disks are touching and that the measurement results might be a bit less precise than with clearly separated star disks Overlapping/Touching star disks indicates that the star disks overlap to the degree of an elongation and that the measurement results is probably less precise than with clearly separated star disks disks indicates star disk overlap to the degree that photometry for the separated components was no longer possible and that it was necessary to resort to the measurement of the combined magnitude Low SNR <20 indicates that the measurement result might be a bit less precise than desired due to a low SNR value but this is already included in the calculation of the error range estimation too bright for reliable photometry indicates a star far brighter than the for plate solving used range 10.5 to 14.5mag despite this most such cases showed a reasonable measurement result anyway In case of questionable astrometric data separation and position angle is calculated based on the RA/Dec coordinates of the components. This is done using the formulas provided by Buchheim 2008 Specifications of the used telescope: T24: 610mm CDK with 3962mm focal length. Resolution 0.625 arcsec/pixel. V-filter. No transformation coefficients available. Located in Auberry, California. Elevation 1405m

Page 356 Table 5. Bessel epoch 2015.837 astrometry and photometry results for the J objects in Equ plus BRT1355 as bonus. Number of observations is 1. RA and Dec are the coordinates based on plate solving with UCAC4 reference stars in the 10.5 to 14.5mag range. Sep is separation calculated as SQRT(((RA2-RA1)*cos(Dec1))^2+(Dec2-Dec1)^2) in radians. Err Sep is the error estimation for Sep calculated as SQRT(dRA^2+dDec^2). The position angle PA is calculated as arctan((ra2-ra1)*cos (Dec1))/(Dec2-Dec1)) in radians and Err_PA is the error estimation for PA calculated as arctan(err_sep/sep) in degrees assuming the worst case that Err_Sep points in the right angle to the direction of the separation means perpendicular to the separation vector. Err Mag stands for the estimated error range calculated from the average delta Vmag over all reference stars used in the image and the SNR value of the star with the formula SQRT(dVmag^2+(2.5*LOG10(1+1/SNR))^2) Name RA Dec Sep Err Sep PA Err PA Mag Err Mag Notes J 158 A 21 02 08.841 10 17 33.41 10.641 0.191. SNR for 5.386 0.270 168.621 2.872 B<20 B 21 02 08.913 10 17 28.13 12.861 0.207 J 159 A 21 08 35.186 09 37 44.36 9.843 0.100 4.171 0.336 245.192 4.606 B 21 08 34.930 09 37 42.61 11.652 0.104 J 161 J 576 J 608 J 848 J 913 J 914 J 1039 A 21 22 28.149 10 57 17.73 10.163 0.091. Touching/ 2.488 0.236 289.735 5.420 B 21 22 27.990 10 57 18.57 10.306 0.091 disks A 21 12 25.542 07 45 06.52 10.791 0.092. Touching/ 2.357 0.297 237.681 7.182 B 21 12 25.408 07 45 05.26 10.844 0.092 disks A 20 59 27.719 11 13 22.35 10.965 0.102. SNR for 5.003 0.304 112.567 3.479 B<10, barely to see B 20 59 28.033 11 13 20.43 14.233 0.227 A 21 09 07.719 04 28 56.66 9.982 0.081. Touching/ 2.806 0.348 140.646 7.074 B 21 09 07.838 04 28 54.49 12.324 0.090 disks A 20 59 09.859 11 28 40.68 10.811 0.111. Touching/ 2.686 0.374 123.697 7.937 B 20 59 10.011 11 28 39.19 12.485 0.121 disks A 21 24 11.162 02 46 59.33 10.800 0.071. Touching/ 2.040 0.311 0.842 8.671 B 21 24 11.164 02 47 01.37 10.978 0.071 disks A 21 25 37.490 02 47 41.91 12.160 0.073. SNR for 4.722 0.291 343.598 3.523 B<20 B 21 25 37.401 02 47 46.44 14.117 0.093 J 1356 A 21 22 26.526 09 52 37.01 7.993 0.255 175.653 1.827 11.936 0.111 B 21 22 26.567 09 52 29.04 12.847 0.113 J 1721 A 21 19 20.592 03 40 56.73 3.161 0.205 272.357 3.714 11.248 0.061 B 21 19 20.381 03 40 56.86 12.587 0.066 Table 5 concludes on next page.

Page 357 Table 5 (conclusion). Bessel epoch 2015.837 astrometry and photometry results for the J objects in Equ plus BRT1355 as bonus. Number of observations is 1. RA and Dec are the coordinates based on plate solving with UCAC4 reference stars in the 10.5 to 14.5mag range. Sep is separation calculated as SQRT(((RA2-RA1)*cos(Dec1))^2+(Dec2-Dec1)^2) in radians. Err Sep is the error estimation for Sep calculated as SQRT(dRA^2+dDec^2). The position angle PA is calculated as arctan((ra2- RA1)*cos(Dec1))/(Dec2-Dec1)) in radians and Err_PA is the error estimation for PA calculated as arctan(err_sep/sep) in degrees assuming the worst case that Err_Sep points in the right angle to the direction of the separation means perpendicular to the separation vector. Err Mag stands for the estimated error range calculated from the average delta Vmag over all reference stars used in the image and the SNR value of the star with the formula SQRT(dVmag^2+(2.5*LOG10(1+1/SNR))^2) Name RA Dec Sep Err Sep PA Err PA Mag Err Mag Notes J 1781 A 21 06 38.930 11 36 54.99 7.499 0.355 116.447 2.711 10.718 0.101 B 21 06 39.387 11 36 51.65 12.405 0.103 J 2341 A 21 19 43.114 05 37 11.38 7.424 0.292 349.926 2.249 12.090 0.092 B 21 19 43.027 05 37 18.69 13.156 0.094 J 2576 A 21 06 55.769 10 29 50.38 14.453 0.127 5.393 0.382 57.973 4.050 B 21 06 56.079 10 29 53.24 14.146 0.139. SNR for A and B<20. No good match with the original Jonckheere 12/13 mags J 2605 BRT1355 A 21 22 21.445 11 13 50.63 12.333 0.088. Touching/ 2.055 0.318 226.301 8.802 B 21 22 21.344 11 13 49.21 12.369 0.090 disks A 21 22 25.570 11 11 01.00 11.491 0.082. Touching 3.912 0.318 194.373 4.651 star disks B 21 22 25.504 11 10 57.21 12.528 0.087 Notes regarding the notes column: indicates that the given values base on one it27 image with 3 seconds exposure time. Touching star disks indicates that the rims of the star disks are touching and that the measurement results might be a bit less precise than with clearly separated star disks. Overlapping/Touching star disks indicates that the star disks overlap to the degree of an elongation and that the measurement results is probably less precise than with clearly separated star disks. disks indicates star disk overlap to the degree that photometry for the separated components was no longer possible and that it was necessary to resort to the measurement of the combined magnitude. Low SNR <20 indicates that the measurement result might be a bit less precise than desired due to a low SNR value but this is already included in the calculation of the error range estimation. too bright for reliable photometry indicates a star far brighter than the range used in plate solving (mag. 10.5 to 14.5), despite this most such cases showed a reasonable measurement result anyway. Specifications of the used telescope: it27: 700mm CDK with 4531mm focal length. CCD: FLI PL09000. Resolution 0.53 arcsec/pixel. V-filter. No B-V transformation coefficients available. Located in Siding Spring, Australia. Elevation 1122m

Page 358 Table 6. Bessel epoch 2015.966 astrometry and photometry results for the J objects in Eri. Number of observations is 1. RA and Dec are the coordinates based on plate solving with UCAC4 reference stars in the 10.5 to 14.5mag range. Sep is separation calculated as SQRT(((RA2-RA1)*cos(Dec1))^2+(Dec2-Dec1)^2) in radians. Err Sep is the error estimation for Sep calculated as SQRT(dRA^2+dDec^2). The position angle PA is calculated as arctan((ra2-ra1)*cos(dec1))/(dec2-dec1)) in radians and Err_PA is the error estimation for PA calculated as arctan(err_sep/sep) in degrees assuming the worst case that Err_Sep points in the right angle to the direction of the separation means perpendicular to the separation vector. Err Mag stands for the estimated error range calculated from the average delta Vmag over all reference stars used in the image and the SNR value of the star with the formula SQRT(dVmag^2+(2.5*LOG10(1+1/SNR))^2) Name RA Dec Sep Err Sep PA Err PA Mag Err Mag Notes J 318 A 04 53 10.255-10 39 17.09 11.319 0.061 4.816 0.219 286.031 2.607 B 04 53 09.941-10 39 15.76 11.738 0.061 J 319 A 05 04 21.336-05 12 59.55 10.982 0.061 3.399 0.213 233.958 3.579 B 05 04 21.152-05 13 01.55 11.821 0.061 J 708 A 04 23 23.450-06 34 15.70 10.596 0.062. Touching/ 2.279 0.248 286.045 6.199 B 04 23 23.303-06 34 15.07 10.836 0.061 disks J 709 04 29 42.350-03 34 40.90-0.248 - - 10.245 0.051. No resolution but elongation according to the listed WDS PA. Combined magnitude 10.245 suggests 10.93/11.07mag for A/ B keeping the given delta_m J 710 A 04 38 19.368-02 42 55.82 10.478 0.061 3.096 0.227 315.817 4.189 B 04 38 19.224-02 42 53.60 11.706 0.066. Touching star disks J 1003 A 04 58 26.324-09 06 00.31 11.287 0.061 5.536 0.262 236.317 2.707 B 04 58 26.013-09 06 03.38 13.151 0.063 J 1004 A 05 08 49.953-08 30 58.89 12.305 0.062 3.233 0.233 320.371 4.130 B 05 08 49.814-08 30 56.40 12.402 0.062 J 1087 A 04 30 12.763-03 37 13.78 11.047 0.101. Touching/ 2.965 0.361 16.723 6.935 B 04 30 12.820-03 37 10.94 13.149 0.109 disks J 1245 A 02 47 29.959-06 00 52.63 10.402 0.076. Touching/ 2.642 0.304 20.149 6.568 B 02 47 30.020-06 00 50.15 10.615 0.083 disks Table 6 concludes on next page.

Page 359 Table 6 (conclusion). Bessel epoch 2015.966 astrometry and photometry results for the J objects in Eri. Number of observations is 1. RA and Dec are the coordinates based on plate solving with UCAC4 reference stars in the 10.5 to 14.5mag range. Sep is separation calculated as SQRT(((RA2-RA1)*cos(Dec1))^2+(Dec2-Dec1)^2) in radians. Err Sep is the error estimation for Sep calculated as SQRT(dRA^2+dDec^2). The position angle PA is calculated as arctan((ra2-ra1)*cos(dec1))/(dec2- Dec1)) in radians and Err_PA is the error estimation for PA calculated as arctan(err_sep/sep) in degrees assuming the worst case that Err_Sep points in the right angle to the direction of the separation means perpendicular to the separation vector. Err Mag stands for the estimated error range calculated from the average delta Vmag over all reference stars used in the image and the SNR value of the star with the formula SQRT(dVmag^2+(2.5*LOG10(1+1/SNR))^2) Name RA Dec Sep Err Sep PA Err PA Mag Err Mag Notes J 1453 A 02 50 07.009-06 16 12.02 10.977 0.092 9.500 0.336 200.296 2.027 B 02 50 06.788-06 16 20.93 11.287 0.092 J 1453 A 02 50 07.009-06 16 12.02 10.977 0.092 38.360 0.336 68.096 0.502 C 02 50 09.396-06 15 57.71 12.974 0.101 J 1455 A 03 03 07.440-02 14 54.05 11.577 0.080 6.257 0.178 63.008 1.630 B 03 03 07.812-02 14 51.21 11.941 0.081 J 1456 A 03 17 30.417-12 22 51.62 11.098 0.101 3.890 0.311 325.603 4.577 B 03 17 30.267-12 22 48.41 11.014 0.101 J 1457 A 03 36 04.465-03 20 04.95 10.104 0.131. Touching 3.277 0.318 220.809 5.548 star disks B 03 36 04.322-03 20 07.43 10.368 0.134 J 1459 A 04 22 00.001-06 25 32.96 10.996 0.052. Touching 3.155 0.278 240.369 5.036 star disks B 04 21 59.817-06 25 34.52 10.919 0.051 Notes regarding the notes column: indicates that the given values base on one it27 image with 3 seconds exposure time. Touching star disks indicates that the rims of the star disks are touching and that the measurement results might be a bit less precise than with clearly separated star disks. Overlapping/Touching star disks indicates that the star disks overlap to the degree of an elongation and that the measurement results are probably less precise than with clearly separated star disks. disks indicates star disk overlap to the degree that photometry for the separated components was no longer possible and that it was necessary to resort to the measurement of the combined magnitude. Low SNR <20 indicates that the measurement result might be a bit less precise than desired due to a low SNR value but this is already included in the calculation of the error range estimation. too bright for reliable photometry indicates a star far brighter than the for plate solving used range 10.5 to 14.5mag despite this most such cases showed a reasonable measurement result anyway. Specifications of the used telescope: -it27: 700mm CDK with 4531mm focal length. CCD: FLI PL09000. Resolution 0.53 arcsec/pixel. V-filter. No B-V transformation coefficients available. Located in Siding Spring, Australia. Elevation 1122m

Page 360 (Continued from page 351) 3. Summary All result tables show, with some exceptions, quite large differences for the magnitudes compared with the WDS data often even in cases where double digit values suggest recent precise measurements. But it is obvious that the Jonckheere objects in more southern constellations have been visited rather often compared to the J-objects in the more northern constellations also with the effect of a far better data quality. A few cases suggest errors in position, separation, and position angle as the difference to the WDS data is larger than the given error estimation. In some cases the available equipment did not allow separate measurement due to heavily overlapping star disks. The measurement of the combined magnitude allowed an estimation of the components on the basis of the given m using the formula provided by Greaney 2012. Special cases: J131B in Lyr: No resolution, B probably fainter than +13mag J1206 in Lyr: WDS gives here for unknown reasons a position slightly different from the WDS ID. The measured position is a better match with the WDS ID (assumed to be the original position given by Jonckheere) and is also confirmed by an elongation in the 2MASS image J1208 in Lyr: Position error in WDS catalog by about 72 arcseconds. Measured position confirmed by UCAC4 catalog with 593-069152 and 593-069151 J2576 in Equ: No good match with the original Jonckheere 12/13 mag estimation. J2576 was not found at the given IDS position by Heintz according to his 1990 paper and the current precise WDS position seems to be given for a potential candidate with similar parameters for separation and position angle but at the cost of a rather bad match of the estimated magnitudes compared with the measured 14.45/14.15mag regarding not only delta_m but also position of the primary. Measurement results confirmed by UCAC4 catalog objects 503-140424 and 503-140426. Unfortunately the star field around the given position does not offer another better matching candidate so we can either take what we have or declare J2576 as lost Jonckheere object. Acknowledgements The following tools and resources have been used for this research: AAVSO APASS (via the UCAC4 catalog) AAVSO VPhot Aladin Sky Atlas v8.0 Astrometrica v4.8.2.405 AstroPlanner v2.2 itelescope it24 & it27 MaxIm DL6 v6.08 SIMBAD, VizieR, UCAC4, URAT1, GAIA UCAC4 catalog via the University of Heidelberg website and directly from USNO DVD Washington Double Star Catalog References Buchheim, Robert 2008, CCD Double-Star Measurements at Altimira Observatory in 2007, Journal of Double Star Observations, Vol. 4 No. 1 Page 28 Greaney, Michael 2012, "Some Useful Formulae" in R.W. Argyle, Observing and Measuring Visual Double Stars, 2nd Edition 2012, Chapter 25, Page 359 Heintz, W.D. 1990, Observations of double stars and new pairs. XIV. Astrophysical Journal Supplement Series Vol. 74, p. 275-290 Knapp, Wilfried; Nanson, John 2016, Jonckheere Double Star Photometry Part I: Cyg, Journal of Double Star Observing, Vol. 12 No 2 pp. nn-mm Knapp, Wilfried 2016, Jonckheere Double Star Photometry Part II: Del, Journal of Double Star Observing, Vol. 12 No 3 pp. nn-mm