NGC 4590 / C1236-264 / Messier 68 (Updated August 2015) RA: 12:39:27.98 DEC: -26:44:38.6 (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 12:39:06.87 -26:42:53.3 R0 0.3496 15.70 0.45 V RR1 2 12:39:15.30 -26:45:24.5 R0 0.5782 15.75 0.72 V RR0 3 12:39:17.35 -26:43:09.9 R0 0.3907 15.64 0.68 V RR01 4 12:39:19.07 -26:46:51.3 R0 0.3962 15.67 0.61 V RR01 5 12:39:23.84 -26:41:51.9 R0 0.2821 15.72 0.45 V RR1 6 12:39:23.78 -26:44:23.4 R0 0.3685 15.69 0.53 V RR1 7 12:39:24.05 -26:45:57.7 R0 0.3880 15.71 0.62 V RR01 8 12:39:25.19 -26:46:52.7 R0 0.3904 15.65 0.53 V RR01 9 12:39:25.58 -26:44:00.8 R0 0.5790 15.72 0.69 V RR0 10 12:39:25.94 -26:44:54.8 R0 0.5519 15.71 1.08 V RR0 11 12:39:26.57 -26:46:32.7 R0 0.3649 15.71 0.55 V RR1 12 12:39:26.92 -26:44:39.7 R0 0.6155 15.56 0.89 V RR0 13 12:39:27.49 -26:45:36.0 R0 0.3617 15.74 0.58 V RR1 14 12:39:27.55 -26:41:04.0 R0 0.5568 15.73 1.11 V RR0 15 12:39:28.50 -26:43:40.6 R0 0.3723 15.68 0.53 V RR1 16 12:39:28.54 -26:43:22.0 R0 0.3820 15.69 0.50 V RR1 17 12:39:29.04 -26:45:52.3 R0 0.6684 15.68 0.82 V RR0 18 12:39:29.13 -26:46:15.0 R0 0.3673 15.72 0.55 V RR1 19 12:39:30.16 -26:43:30.2 R0 0.3916 15.66 0.56 V RR01 20 12:39:30.27 -26:46:33.0 R0 0.3858 15.68 0.56 V RR1 21 12:39:31.21 -26:44:31.2 R0 0.4071 15.62 0.64 V RR01 22 12:39:32.30 -26:45:01.7 R0 0.5634 15.67 1.15 V RR0 23 12:39:32.41 -26:38:22.7 R0 0.6589 15.68 1.11 V RR0 24 12:39:33.16 -26:44:46.7 R0 0.3764 15.68 0.50 V RR1 25 12:39:38.16 -26:42:37.0 R0 0.6415 15.72 0.79 V RR0 26 12:39:39.47 -26:45:22.9 R0 0.4070 15.72 0.80 V RR01 27 12:39:55.93 -26:40:17.0 R0 322.2343 9.80 4.03 V M max;f;Note 28 12:40:00.32 -26:41:59.5 R0 0.6068 15.75 1.18 V RR0 29 12:39:48.94 -26:47:09.9 R0 0.3952 15.71 0.56 V RR01 30 12:39:36.09 -26:45:55.7 R0 0.7336 15.64 0.37 V RR0 31 12:39:19.67 -26:43:05.3 R0 0.3997 15.58 0.66 V RR01 32 12:39:03.29 -26:55:18.0 R0 0.5882 15.58 0.81 V RR0 Note 33 12:39:34.41 -26:43:40.5 R0 0.3906 15.67 0.47 V RR1 34 12:39:47.57 -26:41:03.0 R0 0.4001 15.76 0.6 V RR01 35 12:39:25.20 -26:45:32.6 R0 0.7025 15.56 1.05 V RR0 36 12:39:24.93 -26:45:31.8 R0 0.4153 15.68 0.64 V RR01 37 12:39:26.20 -26:44:21.0 R0 0.3846 15.64 0.47 V RR1 38 12:39:26.13 -26:45:08.0 R0 0.3828 15.63 0.53 V RR1 39 12:39:24.44 -26:44:51.5 R0 0.0640 18.04 0.85 V SXPHE 40 12:39:27.91 -26:45:32.4 R0 ---- 18.31 -- V CST Note;SGB 41 12:39:28.37 -26:43:19.0 R0 ---- 17.98 -- V CST Note;RGB 42 12:39:27.47 -26:44:04.4 R0 ---- 18.36 -- V CST Note;SGB 43 12:39:29.10 -26:45:43.5 R0 0.3706 15.71 0.57 V RR1 44 12:39:29.51 -26:44:38.7 R0 0.3851 15.67 0.48 V RR1 45 12:39:29.90 -26:44:48.9 R0 0.3908 15.72 0.52 V RR01 46 12:39:24.89 -26:44:43.6 R0 0.7383 15.64 0.54 V RR0 47 12:39:28.81 -26:44:20.1 R0 0.3729 15.63 0.49 V RR1 48 12:39:38.29 -26:46:12.3 R0 0.0432 17.29 0.24 V SXPHE 49 12:39:29.52 -26:44:09.3 R0 0.0485 18.09 0.59 V SXPHE 50 12:39:32.12 -26:45:10.5 R0 0.0658 17.56 0.70 V SXPHE 51 12:39:28.99 -26:44:48.5 R0 0.0589 17.24 0.35 V SXPHE 52 12:39:30.57 -26:44:30.1 R0 0.0371 17.90 0.25 V SXPHE 53 12:39:08.91 -26:50:33.8 R0 ---- 16.98 -- V ? f;Note =================================================================== Supplementary Notes The RA and dec for V1-48 are from Samus et al. (2009) and for V49-53, they are from Kains et al. (2015). All of the remaining data in the above table are from Kains et al. (2015) unless indicated otherwise in the Notes on individual stars. =================================================================== Notes on individual stars V27 = FI Hya Shapley (1920) recognized that V27 is a long period variable and Greenstein et al. (1947) established that is a foreground star, not a cluster member, based on the radial velocity they measured. The star is listed in the GCVS as FI Hya and is classified as a Mira. The period, magnitude and amplitude listed in the above table are from the ASAS of Pojmanski (2002). The images of V27 were saturated in Walker's (1994) data and the observations of Kains et al. (2015) did not extend over a long enough time frame. V32 = EN Hya: V32 was outside of the field of view in the studies by Walker (1994) and by Kains et al. (2015). The period, V magnitude, amplitude and classification are from the Southern Catalina Survey (Torrealba et al. 2015). V40, V41, V42: Kains et al. (2015) observed M68 over an interval of 74 days in 2013 and did not detect variability in any of these stars confirming the earlier conclusion of Walker (1994). V53: The mean magnitude is from Kains et al. (2015) who found that the star brightened by about 0.1 mag in V over the course of their observations (80 days). However, they did not detect any variation in the I band light curve of the star. It lies well to the red of the cluster sequence on the CM diagram and is thought to be a red foreground star. =================================================================== Discovery of the variable stars in NGC 4590 (M68): V1-19 Shapley (1919) with x,y coordinates V20-28 Shapley (1920) with x,y coordinates and an ID chart for V1-28 He also listed their photographic magnitudes from 10 plates and these were used by Sawyer (1939) to derive max and min magnitudes for her first catalogue of variable stars in globular clusters. V29-31 Rosino & Pietra (1954a,b) with x,y coordinates V32-38 van Agt & Oosterhoff (1959) with x,y coordinates and ID charts for V1-38 V32 was previously announced as HV 11069 with RA and dec (1900) by Buttery (1942). It has subsequently been desginated as EN Hya in the GCVS. V39-42 Terzan et al. (1973) with x,y coordinates and an ID chart They also announced five new variables in the field around the cluster. V43-48 Walker (1994) with ID chart for all the variables in his investigation. For the variables that were not RR Lyrae, he also published X,Y coordinates in pixels. V49-52 Kains et al. (2015) with RA, dec and an ID chart for all of the variables as well as individual finder charts. V53 = Standard #28 of Walker (1994) who noted that the star was ~0.1 mag fainter in May 1993 than it was in March and July. He published an ID chart and concluded that it was a red foreground star. The number V53 was assigned by Kains et al. (2015) who listed the star's RA and dec. and published an ID chart. ---------------------------------------------------------------- Sariya et al. (2014) announced 9 possible new variables for which they derived periods ranging from 0.26 to 0.54 days. However, in a subsequent study, Kains et al. (2015) observed these stars and did not detect variability in any of them. Therefore they have not been included in the above table. ============================================================== References Buttery, I. G. 1942, Harv. Ann., 109, 25 Clement, C. M., Ferance, S., Simon, N. R. 1993, ApJ, 412, 183 Greenstein, J. L., Bidelman, W. P., Popper, D. M. 1947, PASP, 59, 143 Kains, N., Arellano Ferro, A., Figuera Jaimes, R., Bramich, D., Skottfelt, J., Jorgensen, U. G., Tsapras, Y. and 28 coauthors, 2015, A&A, 578, A128 Pojmanski, G. 2002, Acta Ast., 52, 397 Rosino, L. & Pietra, S. 1954a, Mem. S.A. I., 25, 227 Rosino, L. & Pietra, S. 1954b, Bologna Publ., 6, No. 5 Samus, N. N., Kazarovets, E. V., Pastukhova, E. N., Tsvetkova, T. M., Durlevich, O. V. 2009, PASP, 121, 1378 Sariya, D. P., Lata, S., Yadav, R. K. S. 2013, New Ast., 27, 56 Shapley, H. 1919, PASP, 31, 226 Shapley, H. 1920, ApJ, 51, 49 Terzan, A., Rutily, B., Ounnas, Ch. 1973, IAU Colloq. No. 21, Variable Stars in Globular Clusters and in Related Systems, 76 Torrealba, G., Catelan, M., Drake, A. J., Djorgovski, S. G., McNaught, R. H., Belokurov, V., Koposov, S. and 4 coauthors, 2015, MNRAS, 446, 2251 van Agt, S. L. Th. J. & Oosterhoff, P. Th. 1959, Leid. Ann., 21, 253 Walker, A. R. 1994, AJ, 108, 555