GC 6723 / C1856-367 (Updated June 2016) RA: 18:59:33.14 DEC: -36:37:53.3 (J2000) ============================================================ Bytes Format Explanation 1-8 A8 Star ID 10-32 A11,1x,A11 Position 34-35 A2 Units for position R0 denotes RA, DEC in the J2000 coordinates R5 denotes RA, DEC in the 1950 coordinates XA denotes X, Y in arcseconds XP denotes X, Y in pixels 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 Period ampl C Type Notes/ RA/X Dec/Y Units Remarks ========================================================================= 1 18:59:39.63 -36:41:09.1 R0 0.5384 15.566 1.127 V RR0 2 18:59:44.56 -36:39:08.8 R0 0.5035 15.407 1.342 V RR0 3 18:59:12.97 -36:37:46.2 R0 0.4941 15.440 1.245 V RR0 4 18:59:34.71 -36:36:34.7 R0 0.4511 15.449 1.288 V RR0 5 18:59:32.99 -36:37:01.5 R0 0.5777 15.466 0.797 V RR0 6 18:59:33.91 -36:37:05.3 R0 0.4792 15.438 1.170 V RR0 7 18:59:49.77 -36:39:01.0 R0 0.3077 15.514 0.513 V RR1 8 18:59:34.68 -36:37:42.4 R0 0.4803 15.415 1.326 V RR0 9 18:59:39.50 -36:37:34.5 R0 0.5757 15.345 1.230 V RR0 10 18:59:45.70 -36:36:27.4 R0 0.2523 15.466 0.471 V RR1 11 18:59:44.53 -36:34:02.1 R0 0.5343 15.461 0.989 V RR0 12 18:59:37.08 -36:38:36.5 R0 0.4688 15.472 1.261 V RR0 13 18:59:29.49 -36:39:02.8 R0 0.5065 15.560 1.196 V RR0 14 18:59:30.22 -36:38:34.3 R0 0.6308 15.255 0.869 V RR0 15 18:59:25.57 -36:35:06.3 R0 0.4354 15.338 1.268 V RR0 16 18:59:29.46 -36:36:19.9 R0 0.6963 15.300 0.884 V RR0 17 18:59:36.96 -36:39:33.5 R0 0.5302 15.509 1.026 V RR0 18 18:59:21.88 -36:38:13.3 R0 0.5265 15.467 1.247 V RR0 Note 19 18:59:19.26 -36:39:47.5 R0 0.5347 15.466 1.022 V RR0 20 18:59:33.67 -36:37:13.9 R0 0.4875 15.374 1.312 V RR0 21 18:59:26.79 -36:38:22.9 R0 0.5920 15.414 0.843 V RR0 22 18:59:27.39 -36:37:17.4 R0 0.3087 15.499 0.561 V RR1 23 18:59:37.83 -36:38:05.0 R0 0.6248 15.482 0.475 V RR0 24 18:59:43.13 -36:39:45.0 R0 0.3001 15.501 0.511 V RR1 25 18:59:41.55 -36:34:32.1 R0 ---- 12.65 0.9 V SR Note 26 18:59:16.92 -36:35:20.3 R0 ---- 12.9 0.8 V SR Note 27 18:59:15.11 -36:36:14.5 R0 0.6192 15.410 0.663 V RR0 28 18:59:34.25 -36:39:12.8 R0 0.4869 15.458 1.180 V RR0 29 18:59:34.39 -36:36:51.5 R0 0.4989 15.438 1.188 V RR0 30 19:00:01.58 -36:37:05.4 R0 ---- 14.2 0.8 V IT f;Note 31 18:59:28.07 -36:38:51.9 R0 0.6078 15.461 0.704 V RR0 32 18:59:29.87 -36:39:27.1 R0 0.2875 15.395 0.433 V RR1 33=NV1 18:59:30.27 -36:38:02.3 R0 0.2854 14.732 0.315 V RR1 f?;Note 34=NV2 18:59:33.19 -36:37:58.1 R0 0.5314 15.303 1.186 V RR0 35=NV3 18:59:32.97 -36:38:01.5 R0 0.6065 15.358 0.534 V RR0 36=NV4 18:59:29.31 -36:37:51.2 R0 0.4640 15.380 1.388 V RR0 37=NV5 18:59:30.79 -36:37:44.8 R0 0.5634 15.408 1.065 V RR0 38=NV6 18:59:30.18 -36:37:45.0 R0 0.5720 15.420 0.914 V RR0 39=NV7 18:59:35.79 -36:37:23.2 R0 0.2541 15.443 0.481 V RR1 40=NV8 18:59:35.67 -36:37:52.2 R0 0.5966 15.493 0.810 V RR0 41=NV9 18:59:40.50 -36:38:08.9 R0 0.6592 15.509 0.399 V RR0 42=NV10 18:59:32.03 -36:37:40.7 R0 0.5529 15.500 1.109 V RR0 43=NV11 18:59:30.98 -36:38:32.4 R0 0.3346 15.542 0.653 V RR1 44=NV12 18:59:32.35 -36:37:52.0 R0 0.4401 15.494 1.402 V RR0 45=NV13 18:59:35.38 -36:38:24.1 R0 0.4893 15.558 1.245 V RR0 46=NV14 18:59:55.06 -36:37:31.0 R0 0.6122 15.621 0.468 V RR0 47=NV19 18:59:41.07 -36:38:01.7 R0 0.0531 17.642 0.409 V SXP ======================================================================= Supplementary Notes The data in the above table are from Lee et al. (2014) unless indicated otherwise in the notes on individual stars. The NV numbers listed for V33-V47 are from their paper; the numbers V33-47 have been assigned in this catalogue. ====================================================================== Notes on individual stars V18: The x coordinate listed in the 2001 version of this electronic catalogue was incorrect. This was pointed out by J.-W. Lee in private correspondence in 2003 and by Samus et al. (2009). The correct x,y coordinates: -137.8", -18.2" were listed by Sawyer Hogg (1973) in her 3rd catalogue. V25, V26: The magnitudes and amplitudes are from Lloyd Evans & Menzies (1977) based on the earlier work of Menzies (1974). They derived a tentative period of 140 days for V25, but this was not confirmed by Lee et al. (2014). Both stars are considered to be SR. In Table 3 of Lee et al. (2014), the coordinates of V25 and V26 have been interchanged. The RA and dec listed in the above table for these two stars are from Samus et al. (2009). V30: Menzies (1974) concluded that this star "almost certainly" has no connection with the cluster. It is listed as NSV 24641 in the Moscow GCVS where it is classified as a T Tauri (IT) and is thought to be associated with the R CrA dark cloud, a region of star formation located near NGC 6723 in the sky. In the above table, the RA and dec are from Samus et al. (2009). The mean magnitude and amplitude are from Lee et al. (2014). V33 = NV1: Lee et al. (2014) noted that this star was considerably brighter than the other RR1 variables and concluded that it is probably a foreground star. However, they did not rule out the possibility that it might be a member of a binary system. ====================================================================== Discovery of the variable stars in NGC 6723: V1-16 Bailey (1902) with x,y coordinates (see page 242) and an ID chart (see Plate XI, Fig. 4 which is Plate 252.21 in the scanned version of the paper on SAO/NASA ADS) In subsequent papers, (Bailey 1924a,b), he derived elements for the variables and discovered 6 additional variables in the field near the cluster. V17 = V12 of van Gent (1932) who published x,y coordinates on Bailey's system and RA and dec (epoch 1875) The number V17 was assigned by Sawyer (1939) in her first catalogue. V18-V19 = V123 and V154 of van Gent (1933) who published RA and dec (epoch 1875). The numbers V18 and V19 were assigned by Sawyer (1939) in her first catalogue. She also publsihed x,y coordinates for the two stars. V20 Fourcade et al. (1966) with x,y coordinates and an ID chart They also published ID charts for all of the previously known variables. V21-29 Most of these variables were discovered by Menzies and investigated as part of his 1967 PhD thesis at the Australian National University. They were subsequently discussed by Lloyd Evans & Menzies (1973) and by Menzies (1973), but their positions were not published in these papers. Sawyer Hogg (1973) listed their x,y coordinates in her 3rd catalogue, based on private correspondence with these authors. In a later paper, Menzies (1974) published x,y coordinates for all of the known variables and an ID chart for all except V8 and V20 which were too close to the cluster centre. V30-32 Menzies (1974) with x,y coordinates and an ID chart V33-47 = NV1-14 and NV19 of Lee et al. (2014) who published finding charts and RA & dec. They announced 7 other new variables: 2 delta Scuti variables and 5 W UMa-type eclipsing binaries, but they considered all of these to be field stars based on the absolute magnitudes and distances they derived. For the delta Scuti variables, NV16 and NV18, they calculated the absolute magnitudes from relationships derived by McNamara (2011) and by Cohen & Sarajedini (2012). For the W UMa binaries, NV15, NV17, NV20, NV21, and NV22, they calculated the absolute magnitudes from an empirical relation derived by Rucinski (2000). -------------------------------------------------------------------- Figuera Jaimes et al. (2016) conducted a search for variables in a 41 by 41 arcsecond field around the cluster centre. They recovered V8, V34, V35 and V44, but did not discover any new variables. ===================================================================== References Bailey, S. I. 1902, Harv. Ann., 38 Bailey, S. 1924a, Harv. Circ., 266 Bailey, S. 1924b, Harv. Bull., 803 Cohen, R. E. & Sarajedini, A. 2012, MNRAS, 419, 342 Figuera Jaimes, R., Bramich, D. M., Skottfelt, J., Kains, N., Jorgensen, U. G., Horne, K., Dominik, M. and 26 coauthors, 2016, A&A, 588, A128 Fourcade, C. R., Laborde, J. R., Albarracin, J. 1966, Atlas y Catalogue de Estrellas Variables en Cumulos Globulares al sur de -29 degrees, Cordoba Kovacs, G., Shlosman, I., Buchler, J. R. 1986, ApJ, 307, 593 Lee, J.-W., Lopez-Morales, M., Hong, K., Kang, Y.-W., Pohl, B., Walker, A. 2014, ApJS, 210, 6 Lloyd Evans, T. & Menzies, J. W. 1973, in IAU Colloq. No. 21, Variable Stars in Globular Clusters and in Related Systems, 151 Lloyd Evans, T. & Menzies, J. 1977, MNRAS, 178, 163 McNamara, D. H. 2011, AJ, 142, 110 Menzies, J. 1973, in IAU Colloq. No. 21, Variable Stars in Globular Clusters and in Related Systems, 178 Menzies, J. 1974, MNRAS, 168, 177 Rucinski, S. M. 2000, AJ, 120, 319 Samus, N. N., Kazarovets, E. V., Pastukhova, E. N., Tsvetkova, T. M., Durlevich, O. V. 2009, PASP, 121, 1378 Sawyer, H. B. 1939, Publ. DDO, 1, No. 4 Sawyer Hogg, H. 1973, Publ. DDO, 3, No. 6 van Gent, H. 1932, BAN, 6, 163 van Gent, H. 1933, BAN, 7, 21 ======================================================================