NGC 2419 / C0734+390 RA: 07:38:08.47 DEC: +38:52:56.8 (J2000) (Most recent updates: Membership probability flag - 2024; Remaining data - November 2014) ============================================================ Bytes Format Explanation 1-8 A8 Star ID 10-32 A11,1x,A11 Position 34-35 A2 Membership probability flag based on data published by Prudil & Arellano Ferro (2024) m1: prob >=0.85; m2: prob >=0.7 and <0.85; m3: prob >= 0.5 and <0.7; f: prob <0.5 u: no data available 37-44 F8.4 Period (days) 46-51 F6.3 Mean magnitude (or maximum magnitude if "max" is indicated in the remarks column) 53-57 F5.3 Light amplitude (range of variability) 59 A1 Colour for mean magnitude and amplitude e.g. B, V, R, I, J, K or P (for photographic). 61-65 A5 Type of variable (draft 2006 GCVS classifications) CST denotes non variable stars previously designated as variables 67-80 A19 Notes and Remarks (f denotes field star) "--" or "----" indicates no data available ========================================================================= ID Position Mem Period ampl C Type Notes/ RA Dec Flag Remarks ========================================================================= 1 07:38:11.61 +38:51:59.0 m1 198.0000 17.437 -- V LB Note 2 07:38:07.96 +38:52:33.7 m1 0.6702 19.331 0.881 V RR0 blend 3 07:38:12.71 +38:52:27.4 m1 0.6260 20.344 1.091 V RR0 4 07:38:15.13 +38:52:35.1 m1 0.3921 20.317 0.502 V RR1 5 07:38:11.14 +38:53:38.8 m1 0.6559 20.180 -- V RR0 Note 6 07:38:12.89 +38:50:43.8 m1 0.3716 20.373 0.596 V RR1 7 07:38:16.19 +38:54:18.8 m1 0.6273 20.357 1.088 V RR0 8 07:38:06.84 +38:53:34.1 m1 13.0000 17.362 0.118 V LB 9 07:38:05.63 +38:54:21.2 m1 0.6447 20.219 -- V RR0 Note 10 07:38:09.89 +38:52:01.1 m1 19.0500 17.123 0.344 V LB 11 07:38:16.43 +38:52:42.3 m1 0.5892 20.339 -- V RR0 Note 12 07:38:19.79 +38:54:41.0 m1 0.6619 20.268 0.970 V RR0 13 07:38:16.93 +38:52:40.2 m1 0.6403 20.304 0.885 V RR0 14 07:37:58.39 +38:52:42.3 m1 0.7413 20.238 0.962 V RR0 15 07:38:13.66 +38:53:30.6 m1 0.6400 20.283 0.858 V RR0 16 07:38:12.38 +38:54:03.4 m1 0.6661 20.295 1.124 V RR0 17 07:38:17.74 +38:54:41.0 m1 0.6490 20.319 1.134 V RR0 18 07:38:07.17 +38:54:46.8 m1 1.5787 18.873 0.750 V CWA 19 07:37:59.02 +38:52:15.0 f 0.7026 20.284 0.952 V RR0 20 07:38:05.96 +38:53:38.2 m1 52.9500 17.386 -- V LB Note 21 07:38:03.58 +38:53:23.7 m1 0.6861 20.202 1.074 V RR0 22 07:38:17.65 +38:52:44.4 m1 0.5767 20.363 1.109 V RR0 23 07:38:10.70 +38:54:10.7 m1 0.6266 20.368 1.029 V RR0 24 07:37:55.61 +38:52:45.7 m1 0.6527 20.365 0.886 V RR0 25 07:38:03.28 +38:53:31.7 m1 0.6363 20.334 1.076 V RR0 26 07:38:02.20 +38:52:03.2 m1 0.6649 20.178 0.923 V RR0 27 07:38:09.78 +38:51:09.0 m1 0.34 20.407 -- V RR1 Note 28 07:37:51.81 +38:53:56.1 u 0.6456 20.350 -- V RR0 Note 29 07:38:03.26 +38:52:46.9 m1 0.7256 20.278 0.777 V RR0 30 07:38:06.09 +38:53:16.2 m1 0.5846 20.322 1.065 V RR0 31 07:38:21.24 +38:50:22.9 m1 0.3875 20.344 0.493 V RR1 32 07:38:06.70 +38:53:40.8 m1 0.6422 20.147 -- V RR0 Note 33 07:38:12.27 +38:52:33.9 m1 0.4112 20.323 0.474 V RR1 34 07:38:10.34 +38:55:29.1 m1 0.4035 20.364 0.482 V RR1 35 07:38:12.01 +38:52:59.9 m1 0.6772 20.265 0.867 V RR0 36 07:38:10.30 +38:53:35.3 m1 0.6482 20.299 0.773 V RR0 37 07:38:11.20 +38:53:09.1 u 0.6610 20.276 -- V RR0 Note 38 07:38:08.13 +38:52:03.9 m1 0.3690 20.248 0.457 V RR1 Note 39 07:38:10.72 +38:50:51.1 m1 0.4070 20.344 0.474 V RR01 Note 40 07:38:13.09 +38:52:47.2 m1 0.5756 20.217 1.074 V RR0 41 07:38:07.20 +38:53:23.1 m1 0.3965 20.334 0.430 V RR1 42 07:38:08.72 +38:52:45.7 u 0.6100 20.293 0.758 V RR0 43 07:38:07.56 +38:52:35.1 m1 0.3800 20.222 0.147 V RR1 44 07:38:09.67 +38:52:41.3 f 0.8758 17.393 0.174 V ? 45 07:38:06.53 +38:52:54.8 m1 0.3139 20.387 0.195 V RR1 46 07:38:06.45 +38:52:50.8 m1 0.7740 20.217 -- V RR0 Note 47 07:38:08.60 +38:53:14.7 m1 0.6568 20.312 -- V RR0 Note 48 07:38:10.04 +38:52:41.2 m1 0.3749 20.214 0.476 V RR1 49 07:38:08.13 +38:53:15.9 m1 0.3271 20.364 0.510 V RR1 50 07:38:07.98 +38:53:16.2 m1 0.6984 20.191 -- V RR0 Note 51 07:38:06.19 +38:52:57.5 m1 0.3484 20.195 0.530 V RR1 52 07:38:09.59 +38:53:12.4 m1 0.3323 20.427 0.410 V RR1 53 07:38:07.78 +38:53:17.3 m1 0.6585 20.007 0.805 V RR0 54 07:38:10.53 +38:52:50.6 m1 0.4316 19.410 0.260 V RR1 55 07:38:05.99 +38:52:59.6 m1 0.3877 20.311 0.400 V RR1 56 07:38:07.99 +38:52:24.7 u 0.3058 20.286 0.287 V RR1 57 07:38:06.00 +38:52:42.7 m1 0.7364 19.948 0.741 V RR0 58 07:38:10.64 +38:53:00.3 m1 0.3882 20.340 0.472 V RR1 59 07:38:10.43 +38:53:09.5 m1 0.8035 20.233 0.527 V RR0 60 07:38:06.66 +38:53:18.8 m1 0.3905 20.299 0.509 V RR1 61 07:38:08.59 +38:52:16.1 u 0.0527 23.069 0.713 V SXPhe 62 07:38:08.32 +38:53:31.4 f 0.5925 20.328 1.025 V RR0 63 07:38:10.98 +38:53:16.4 m1 0.3449 20.306 0.519 V RR1 64 07:38:10.29 +38:52:16.3 f 0.7800 20.314 0.456 V RR0 65 07:38:11.32 +38:52:28.2 m1 0.3228 20.109 0.230 V RR1? 66 07:38:11.60 +38:53:10.5 m1 0.3868 20.340 0.443 V RR1 67 07:38:10.97 +38:53:23.5 m1 0.3399 20.364 0.453 V RR1 68 07:38:12.15 +38:52:49.0 m1 0.3647 20.335 0.499 V RR1 69 07:38:10.64 +38:53:37.7 u 0.3409 20.430 0.500 V RR1 70 07:38:08.47 +38:53:46.6 m1 0.4155 20.143 0.339 V RR1 71 07:38:07.33 +38:51:56.3 u 0.0492 23.066 0.418 V SXPhe 72 07:38:09.92 +38:53:49.5 m1 0.4146 20.376 0.455 V RR1 73 07:38:11.52 +38:52:01.8 u 0.0529 22.967 0.383 V SXPhe 74 07:38:13.78 +38:52:47.9 m1 0.3057 20.414 0.200 V RR1 75 07:38:03.54 +38:52:16.9 m1 0.3236 20.352 0.443 V RR1 76 07:38:12.11 +38:51:59.2 m1 0.4411 20.301 0.474 V RR1 77 07:38:13.14 +38:52:08.2 m1 0.3811 20.379 0.489 V RR1 78 07:38:13.75 +38:53:25.5 u 0.0412 23.027 0.273 V SXPhe 79 07:38:13.19 +38:52:00.0 u 0.0494 22.801 0.767 V SXPhe 80 07:38:01.81 +38:53:16.6 m1 0.6161 20.648 0.604 V RR0 81 07:38:12.10 +38:53:57.4 u 0.0629 22.651 0.424 V SXPhe 82 07:38:13.85 +38:53:37.3 m1 0.3473 20.318 0.303 V RR1 83 07:38:08.54 +38:51:31.4 u 0.1403 22.548 0.199 V SXP? Note 84 07:38:01.46 +38:53:12.0 m1 0.3271 20.323 0.416 V RR1 85 07:38:01.85 +38:54:10.4 u 0.0500 22.906 0.413 V SXPhe 86 07:38:19.62 +38:53:15.7 m1 49.6000 17.466 0.289 V LB 87 07:38:18.40 +38:51:26.3 u 0.2340 23.157 1.200 V EA 88 07:38:10.57 +38:49:53.4 u 0.0537 22.879 0.281 V SXPhe 89 07:38:19.78 +38:55:07.4 f 0.2897 20.409 0.079 V RR1 90 07:38:23.14 +38:54:11.6 m1 0.3974 20.392 0.457 V RR1 91 07:37:52.82 +38:54:14.4 u 0.3893 20.379 0.475 V RR1 92 07:38:51.64 +38:53:49.6 u 5.6300 19.548 0.112 V ? 93 07:37:49.89 +38:44:59.9 u 0.0566 22.923 0.216 V SXPhe 94 07:38:26.11 +38:58:10.2 u 0.7133 20.318 0.590 V RR0 95 07:37:29.36 +38:54:33.9 u 0.1483 19.228 0.064 V DSCT f;Note 96 07:37:39.61 +38:51:35.8 u 0.3597 19.085 0.887 V EA 97 07:38:18.41 +38:49:51.3 u 0.0502 22.690 0.327 V SXPhe 98 07:37:38.96 +38:50:22.0 u 0.2300 22.553 0.604 V ? 99 07:38:28.63 +38:49:15.4 u 0.2015 18.526 0.127 V EC 100 07:37:52.71 +38:48:11.6 u 0.1309 18.335 0.264 V DSCT f;Note 101 07:38:14.88 +38:50:24.7 u 0.0504 22.714 0.459 V SXPhe ================================ Supplementary Notes With an integrated absolute magnitude of -9.42, NGC 2419 is one of the brightest globular clusters in the Milky Way according to the 2010 update to the Harris (1996) catalogue. In fact, studies by Bruns & Kroupa (2011), Cohen et al. (2010), Di Criscienzio et al. (2011b) and Davies et al. (2024) all support the hypothesis that this cluster is the remnant of a much more massive system. NGC 2419 is also one of the most distant clusters. As a result, the mean magnitude of the stars on its horizontal branch is fainter than V=20.0 mag, making it difficult to study its RR Lyrae population. The most comprehensive investigation of the variables in NGC 2419 was by Di Criscienzo et al. (2011a, hereafter DiC), based on observations obtained with the 3.5 metre Galileo telescope in the Canary Islands These were supplemented by HST archival observations spanning 6 years and 4 nights of photometry obtained with the 8.2 Subaru telescope in Hawaii. The data listed in the above table are from the V photometry reported in their paper. Their study also included some BI data. In a more recent investigation, Arellano Ferro et al. (2024, hereafter AF) observed NGC 2419 with a 2-metre telescope at the Indian Astrophysical Observatory and obtained data for some of the brighter variables. They published ID charts for the variables in their investigation. They also published membership status, based on Gaia-DR3 data and found that most of the variables they observed were cluster members, except V89. The cluster also has a large population of blue straggler stars. Dalessandro et al. (2008) published RA, Dec, and BVI photometry for 232 BSS candidates and noted that their radial distribution was essentially the same as that of the other stars in the cluster. ================================================================== Notes on individual stars V1, V5, V9, V11, V20, V27, V28, V32, V37, V46, V47, V50: No V amplitudes have been listed in the above table for these stars because the values listed by DiC were lower limits: V1 (0.477), V5 (1.048), V9 (0.798), V11 (0.779), V20 (0.278), V27 (0.275), V28 (0.675), V32 (0.680), V37 (1.056), V46 (0.622), V47 (0.622), V50 (0.653) V27: The period is difficult to define. Three datasets obtained at different epochs: Baade (1935), Pinto & Rosino (1977) and DiC can not be phased by a single period because the period changed from P=0.35184 days (Baade), to P=0.34896 days (Pinto & Rosino) to the value P=0.34519 days inferred from the data of DiC and finally P=0.342 (AF). The y coordinate for V27 was incorrectly listed as +103 in our earlier electronic catalogues. It should be -103. The correct y coordinate was listed in Sawyer Hogg's published catalogues and in the papers by Pinto & Rosino (1976, 1977). V38, V39: Samus (2009, private communication) pointed out that the y coordinates listed for these two variables in our previous electronic catalogues were incorrect. The values that we listed were the ones published by Pinto & Rosino (1976, 1977) in their discovery papers, but were not in agreement with the labelled positions on their ID charts. According to Samus, the correct coordinates are y(V38) = -48" (instead of -65") and y(V39) = -119" (instead of -128"). V39: This is a double-mode RR Lyrae star with period ratio P1/P0= 0.745. In the above table, the pulsation characteristics of the first- overtone pulsation are reported; the pulsation characteristics of the fundamental mode are P0=0.54621 days, A_V=0.347 mag. The RR01 classification for V39 was originally made by Clement & Nemec (1990) who derived P1=0.40704, P0=0.5465 and A1/A0= 1.35 based on the data of Pinto & Rosino (1977). This is in good agreement with the study by DiC. V83: This star is in the blue straggler region and is tentatively classified as an SX Phoenicis variable. However with its period of about 0.14 days, it deviates significantly from the PL relation defined by the other SX Phe variables in the cluster. V95, V100: The field status for these two variables is from DiC who classfied them as field delta Scuti stars which were too tight to belong to the cluster. ================================================================== Discovery of the variable stars in NGC 2419: V1-36 Baade (1935, ApJ 82, 396) with x,y coordinates and an ID chart He said his list should be complete for variables at distances greater than 40 arcsec form the cluster centre, but no attempt was made to discover variables in the central burnt out area. Baade also listed max and min magnitudes for many of the variables and Sawyer published these in her 1939 (first) catalogue. There was some confusion about the magnitudes for V35 and in her 1955 (second) catalogue, this was clarified after private correspondence with Baade. V37-41 Pinto & Rosino (1976, 1977) with x,y coordinates for V1-41 listed in both papers and an ID chart in the 1977 paper V42-101 Ripepi et al (2007) anounced the discovery of these variables. DiC described them in more detail and published J2000 RA and Dec coordinates for all 101 variables. AF observed and analysed many of these variables and published ID charts for the variables in their investigation. ===================================================================== References Arellano Ferro, A., Muneer, S., Giridhar, S., Bustos Fierro, I., Yepez, M. A., Garcia Perez, G. A., Rios Segura, G. 2024, Rev. Mex. A&A, 60, 277 = arXiv:2404.19151v1 (AF) Baade, W. 1935, ApJ, 82, 396 Bruns, R. C. & Kroupa, P. 2011, ApJ, 729, 69 Clement, C. & Nemec, J. 1990, JRASC, 84, 434 Cohen, J. G., Kirby, E. N., Simon, J. D., Geha, M. 2010, ApJ, 725, 288 Dalessandro, E., Lanzoni, B., Ferraro, F. R., Vespe, F., Ballazzini, M., Rood, R. T. 2008, ApJ, 681, 311 Davies, E. Y., Belokurov, V., Monty, S., Wyn Evans, N. 2024, MNRAS, 529, L73 Di Criscienzo, M., Greco, C., Ripepi, V., Clementini, G., Dall'Ora, M., Marconi, M., Musella, I., Frederici, L. Di Fabrizio, L. 2011a, AJ, 141, 81 (DiC) Di Criscienzo, M., D'Antona, F., Milone, A. P., Ventura, P., Caloi, V., Carini, R., D'Ercole, A., Vesperini, E., Piotto, G. 2011b, MNRAS, 414, 3381 Harris, W. E. 1996, AJ, 112, 1487 Pinto, G. & Rosino, L. 1976, IBVS, 1159 Pinto, G. & Rosino, L. 1977, A&A Supp, 28, 427 Prudil Z., Arellano Ferro, A. 2024, MNRAS, 534, 3654 Ripepi, V., Clementini, G., Di Criscienzo, M., Greco, C., Dall'Ora, M., Frederici, L., Di Fabrizio, L., Musella, I., Marconi, M., Baldacci, L., Maio, M. 2007, ApJ, 667, L61 =========================================================================