C2304+124 / Palomar 13 (Updated September 2014) 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 23:06:41.54 +12:46:58.4 R0 0.5382 17.65 1.0 V RR0 2 23:06:44.49 +12:46:15.7 R0 0.5971 17.70 1.0 V RR0 3 23:06:43.13 +12:46:48.0 R0 0.5782 17.65 1.2 V RR0 4 23:06:48.83 +12:41:22.3 R0 0.5753 17.80 0.8 V RR0 Note ==================================================================== Supplementary Notes The periods, magnitudes, amplitudes and variability types for V1-4 are from Ciatti et al. (1965). =============================================================== Notes on individual stars V4: Although V4 is located at a distance of approximately 5 arcminutes from the cluster centre, well beyond the tidal radius (2.2 arcmin) derived from the 2010 update to the Harris (1996) catalog, Siegel et al. (2001) concluded that it is a probable cluster member, based on its proper motion. =========================================================== 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. -------------------------------------------------------------------- Siegel et al. (2001) carried out a search for variable stars and detected the four known variables, but did not discover any new ones. Palomar 13 has a significant population of blue straggler stars. See Hamren et al. (2013) and references cited by them. None of the BS stars have yet been identified as variables. ==================================================================== References Ciatti, F., Rosino, L., Sussi, M. G. 1965, Verofff. der Remeis-Sternwarte Bamberg, Bd. IV, Nr. 40, 228 Hamren, K. M., Smith, G. H., Guhathakurta, P., Dolphin, A. E., Weisz, D. R., Rajan, A., Grillmair, C. J. 2013, AJ, 146, 116 Harris, W. E. 1996, AJ, 112, 1487 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 ====================================================================