COMMISSION 27 OF THE I. A. U. INFORMATION BULLETIN ON VARIABLE STARS Number 1159 Konkoly Observatory Budapest 1976 July 27 MAGNITUDES AND ELEMENTS OF VARIABLE STARS IN THE REMOTE GLOBULAR CLUSTER NGC 2419 Mean B magnitudes and elements of 41 variable stars in the remote globular cluster NGC 2419 have been derived by examining 109 plates (103a-O + GG13) obtained at Asiago, at the cassegrain focus of the Copernicus 182 cm telescope of Mount Ekar from 1973 to 1976. Comparison sequences were selected among the program stars of Racine and Harris (1975). The observations of the variables made by Baade (1935) on forty Mt. Wilson plates were also discussed, after reduction of the magnitudes to the present system. Five new variables have been discovered in the course of this research. The results are summarized in Table 1 and Notes. The cluster contains 36 RR Lyrae variables, one 1-day cepheid and four semiregular or irregular red stars. The frequency distribution of the periods of the RR Lyr variables indicates that the cluster belongs to Oosterhoff's class II, with a concentration of the periods around 0.654d for 25 RR-a and 0.384d for 7 RR-c. The mean median magnitude of 36 RR Lyrae variables is 20.49 +- 0.11. Assuming for the corresponding median absolute magnitude the value M_B= +0.8, the uncorrected distance modulus is 19.7 and the distance of the same order (87 kpc) than found by Racine and Harris. Further details and light curves will be given in a forthcoming publication. G. PINTO L. ROSINO Astrophysical Observatory of the University of Padova References: 1. Baade, W. 1935, Ap.J. 82, 396. [BIBCODE 1935ApJ....82..396B ] 2. Racine, R., Harris, W.E. 1975, Ap.J. 196, 413. [BIBCODE 1975ApJ...196..413R ] Table 1 Magnitudes and elements of variable stars in NGC 2419 No x y max min med T_0 P Notes 244 1 + 40" - 52" 18.40 19.20 18.80 ---- --- 1 2 - 4 - 19 19.80 21.10 20.45 2076.50 0.6692d 2 3 + 52 - 24 19.95 21.15 20.55 2043.50 0.625967 4 + 80 - 15 20.25 21.10 20.68 1986.53 0.39257 3 5 + 33 + 47 19.91 20.95 20.43 2345.63 0.655880 6 + 56 -127 20.25 20.95 20.60 2035.55 0.371667 7 + 91 + 87 19.96 21.09 20.53 2076.62 0.627331 8 - 17 + 41 18.30 19.10 18.70 ---- ---- 4 9 - 32 + 88 19.86 20.95 20.41 2361.61 0.644733 10 + 20 - 51 18.19 18.94 18.57 2515.50 81.30 5 11 + 95 - 8 19.84 20.93 20.39 2128.44 0.589322 12 +133 +111 19.90 21.16 20.53 2076.02 0.661814 13 +101 - 10 19.93 21.06 20.50 2361.61 0.640258 14 -115 - 13 19.83 21.06 20.45 2345.60 0.741371 15 + 62 + 40 19.91 21.04 20.48 2076.50 0.640006 16 + 47 + 72 19.92 21.09 20.51 2045.46 0.666084 17 +109 +111 19.81 21.18 20.50 2396.59 0.649033 18 - 15 +114 18.66 19.65 19.16 2402.52 1.578524 6 19 -107 - 40 19.93 21.01 20.47 1986.52 0.702620 20 - 28 + 45 18.20 19.20 18.70 ---- ---- 7 21 - 55 + 30 19.98 21.00 20.49 2123.44 0.686094 22 +109 - 5 19.85 21.15 20.50 2119.37 0.576645 23 + 27 + 79 19.69 20.73 20.21 2121.30 0.62648: 8 24 -147 - 10 19.92 21.00 20.46 2451.32 0.652697 25 - 59 + 38 19.95 21.01 20.48 2424.42 0.636328 26 - 70 - 30 19.56 20.69 20.13 2361.58 0.664924 9 27 + 19 -103 20.34 20.79 20.57 2345.67 0.34896 10 28 -192 + 59 19.91 20.90 20.41 2402.63 0.646539 29 - 58 - 7 20.23 21.00 20.62 2045.46 0.725543 11 30 - 26 + 23 20.00 21.10 20.55 ---- ---- 12 31 +154 -146 20.27 20.93 20.60 2035.53 0.38753 32 - 19 + 48 19.93 20.96 20.45 2416.43 0.642240 33 + 47 - 17 20.30 20.94 20.62 1985.65 0.377620 34 + 21 +157 20.33 20.95 20.64 2071.43 0.403485 35 + 43 + 8 20.15 21.06 20.61 2121.35 0.677178 36 + 23 + 44 20.04 21.13 20.59 2121.41 0.648311 37 + 21 + 12 19.95 21.05 20.50 2424.43 0.661044 38 - 1 - 65 19.90 20.90 20.40 ---- ---- 13 39 + 28 -128 20.23 20.88 20.56 1989.60 0.40703 40 + 58 - 9 19.50 21.10 20.50 ---- ---- 14 41 - 5 + 21 20.00 20.90 20.45 ---- ---- 14 Notes to Table 1 1. Red irregular variable. Mean B-V color index: +1.8. 2. The variable is situated within the central part of the cluster, in a crowded area. Estimates of the magnitude are difficult and this explains the large dispersion of the points in the light curve. 3. RR-c. Baade's observations are not represented in the light curve. 4. Red irregular variable. Mean B-V color index: +1.7. 5. Red semiregular variable. Mean B-V color index: +1.6. 6. This star belongs to the group of cepheids with period between 1 and 3 days which are well represented in globular clusters. Mean B-V color index: +0.35. 7. Red irregular variable. Mean B-V color index: +1.7. 8. The variable is the south-east component of a double star. Only on some of the best plates the two stars are separated. The presence of the companion strongly influences the estimates of magnitude, which appears brighter than in the other RR Lyr variables of the cluster. 9. The variable is close to a star of about 20.5 which influences the estimates. 10. RR-c. The period is somewhat uncertain and does not represent the Baade's observations. 11. The Baade's observations fit in the light curve, but are somewhat scattered. 12. In the most part of the plates the variable is blended with the images of nearby stars so that reliable estimates are not possible. Very likely RR-a, but the elements have not been found. 13. The variable is deeply inside the cluster. Very likely RR-a but the period has not been found. 14. The variable is in the central crowded area of the cluster and only a small number of estimates are available. The elements have not been found.