C2304+124 / Palomar 13 (Updated March 2019) RA: 23:06:44.44 DEC: +12:46:19.2 (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 23:06:41.53 +12:46:58.9 R0 0.5382 17.886 0.80 V RR0 2 23:06:44.47 +12:46:16.1 R0 0.5971 17.819 0.79 V RR0 3 23:06:43.14 +12:46:47.8 R0 0.5782 17.766 0.83 V RR0 4 23:06:48.83 +12:41:22.3 R0 0.5751 17.886 0.52 V RR0 5 23:06:37.28 +12:49:27.5 R0 7.26 17.029 0.4 V SR? ==================================================================== Supplementary Notes The data are from Yepez et al. (2019) who concluded that all of these variables are cluster members, based on their proper motion and location in the CM diagram. In an analysis of the structure and dynamics of Pal 13, Bradford et al. (2011) derived a tidal radius of 13.9 arcminutes, which is considerably larger than previously assumed (Harris 2010). V1-5 are all well within Bradford's tidal radius. =========================================================== Discovery of the variable stars in Pal 13: V1-4 Rosino (1957) with x,y positions and ID chart An ID chart with the variables labelled was also published by Rosino & Ortolani (1985) - see Fig. 9 and by Ortolani et al. (1985) - see Fig. 1. V5 Yepez et al. (2019) with RA, dec (2000) and an ID chart These authors discovered 3 additional variables which they called Var 1, Var 2 and Var 3, but none of them are considered to be cluster members and are therefore not listed in the above table. -------------------------------------------------------------------- Palomar 13 has a significant population of blue straggler stars. However, none of them have been identified as variables in searches carried out by Siegel et al. (2001) and by Yepez et al. (2019) ==================================================================== References Bradford, J. D., Geha, M., Munoz, R. R., Santana, F. A., Simon, J. D., Cote, P., Stetson , P. B. and 2 co-authors, 2011, ApJ, 743, 167 Harris, W. E. 2010, arXiv:1012.3224 Ortolani, S., Rosino, L., Sandage, A. 1985, AJ, 90, 473 Rosino, L. 1957, Mem. SAI, 28, 293 = Asiago Cont. No. 85 Rosino, L. & Ortolani, S. 1985, Mem. SAI, 56, 113 Siegel, M. H., Majewski, S. R., Cudworth, K. M., Takmiya, M. 2001, AJ, 121, 935 Yepez, M. A., Arellano Ferro, A., Schoeder, K. P., Muneer, S., Giridhar, S., Allen, C. 2019, New Ast. 71, 1 ====================================================================