NGC 5466 / C1403+287 (Updated October 2010) RA: 14:05:27.29 DEC: +28:32:04.0 (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 14:06:33.12 +28:30:25.4 R0 0.5774 16.30 1.0 P RR0 Note 2 14:05:23.42 +28:30:01.7 R0 0.5874 16.504 0.8 V RR0 Bl 3 14:05:25.77 +28:31:44.8 R0 0.5781 16.508 1.15 V RR0 4 14:05:21.98 +28:32:00.9 R0 0.5113 16.578 1.60 V RR0 Bl 5 14:05:23.11 +28:33:43.6 R0 0.6152 16.468 0.99 V RR0 Bl 6 14:05:37.27 +28:31:29.9 R0 0.6210 16.471 1.05 V RR0 7 14:05:12.31 +28:28:04.9 R0 0.7034 16.455 0.74 V RR0 8 14:05:29.80 +28:31:47.4 R0 0.6291 16.500 0.96 V RR0 9 14:05:30.42 +28:32:08.7 R0 0.6850 16.423 0.98 V RR0 10 14:05:34.49 +28:32:39.3 R0 0.7093 16.409 0.89 V RR0 11 14:05:36.91 +28:33:01.6 R0 0.6077 16.512 0.97 V RR0 Bl? 12 14:05:29.41 +28:30:24.3 R0 0.2942 16.506 0.35 V RR1 13 14:05:24.44 +28:30:39.2 R0 0.3416 16.539 0.55 V RR1 14 14:05:24.49 +28:32:44.9 R0 0.7859 16.368 0.65 V RR0 15 14:05:45.05 +28:32:14.4 R0 0.3986 16.464 0.44 V RR1 16 14:05:16.86 +28:28:55.3 R0 0.4245 16.414 0.52 V RR1 17 14:05:23.58 +28:31:22.3 R0 0.3701 16.293 0.41 V RR1 blend? 18 14:05:31.45 +28:32:33.8 R0 0.3744 16.534 0.45 V RR1 19 14:05:40.48 +28:29:12.4 R0 0.8213 14.731 0.60 V AC 20 14:05:11.30 +28:32:31.6 R0 0.3020 16.576 0.33 V RR1 Note 21 14:05:31.86 +28:31:42.7 R0 0.7910 16.423 0.20 V RR0 22 14:05:16.47 +28:30:31.2 R0 ---- -- -- CST Note 23 14:05:53.01 +28:32:09.2 R0 0.8150 16.405 0.18 V RR Note 24 ---- ---- ---- -- -- =V20 25 ---- ---- ---- -- -- =V21 26 14:05:31.08 +28:30:54.5 R0 ---- -- -- CST Note 27 14:05:27.93 +28:30:58.0 R0 ---- -- -- CST Note 28 14:05:24.56 +28:31:59.1 R0 0.3421 18.54 0.28 V EC =NH19 29 14:05:29.09 +28:31:12.8 R0 0.2975 19.35 0.32 V EC =NH30 30 14:05:35.05 +28:31:19.5 R0 0.5113 18.86 0.33 V EA =NH31 31 14:05:23.59 +28:31:37.5 R0 0.0403 18.798 0.138 V SXPHE =NH29,Note 32 14:05:25.90 +28:31:02.4 R0 0.0450 19.112 0.230 V SXPHE =NH49 33 14:05:28.05 +28:31:07.9 R0 0.0499 18.876 0.442 V SXPHE =NH35 34 14:05:20.71 +28:31:53.3 R0 0.0507 18.640 0.152 V SXPHE =NH27 35 14:05:35.06 +28:30:45.2 R0 0.0505 18.986 0.256 V SXPHE =NH39 36 14:05:28.10 +28:32:37.0 R0 0.0552 18.790 0.378 V SXPHE =NH38 37 ---- ---- 0.3224 15.75 0.03 V ? 38 ---- ---- 0.3777 15.17 0.02 V ? 39 14:05:39.25 28:31:18.50 R0 0.0480 18.939 0.342 V SXPHE =SXP1 40 14:05:29.05 28:31:56.70 R0 0.0451 19.133 0.046 V SXPHE =SXP2 41 14:05:28.12 28:34:49.10 R0 0.0386 19.277 0.062 V SXPHE =SXP3 ======================================================================== Supplementary Notes The RA and dec for V1-36 were taken from Samus et al. (1999) and for V39-41 from Jeon et al. (2004). Jeon et al. also derived RA and dec for V31-36 and these are in good agreement with the values of Samus et al. The periods, magnitudes and classifications for all of the variables numbered from V1-27 (with the exception of V1 and V20) are from Corwin et al. (1999). V1 and V20 are discussed in the notes on individual variables. Periods, magnitudes, amplitudes and classification for V28-30 are from Mateo et al. (1990) who concluded that all three were probably cluster members. The membership status for V28 and V29 was confirmed by Rucinski (2000). V30 was not included in his study. Periods, magnitudes, amplitudes and classifications for V31-V36 are from Jeon et al. (2004) who listed the stars according to the numbering system of the Nemec & Mateo (1990): NH 29, 49, 35, 27, 39, 38. All the data for V37 and V38 are from the paper by Arellano Ferro et al. (2008). The periods they derived are in the RR Lyrae range, but with unusally low amplitudes. They are brighter than the RR Lyrae variables in the cluster and might be field stars. All of the data listed for V39-41 are from the paper by Jeon et al. (2004). Their paper presented several frequencies and amplitudes. The periods that we list in the above table are the ones associated with their dominant frequency. ============================================= Notes on individual stars V1: With x=+858" and y+-95", this variable was outside the field of view in the CCD studies. The period and magnitudes listed in the above table are from Gryzunova (1972). V20: The period derived for V20 by Corwin et al. (1999) did not fit the data well. The period, magnitude and classification we list in the above table for this star are from Arellano Ferro et al. (2008). The amplitude was estimated from their light curve. These authors published periods and magnitudes for the other RR Lyrae, but since they did not publish amplitudes, we have listed the Corwin et al. (1999) data instead. We found that the mean V magnitudes (A_0 values) published by Arellano Ferro et al. were on average 0.07 mag fainter than the _int values published by Corwin et al. V22: This star (Hopmann 35) was announced as a variable by Gryzunova (1969) who subsequently derived a period of 0.2321607 days (Gryzunova 1972). The number V22 was assigned by Sawyer Hogg (1973) in her 3rd catalog. However, Corwin et al. (1999) could not locate V22 at the coordinates (-153, -80) reported by Gryzunova and Sawyer Hogg. They also pointed out that Buonanno et al. (1984) did not identify this star as a candiate variable even though it was in their field of view. The star appears to be the star Cuffey (1961) identified as 1-3-8 with V=16.56 at the blue end of the HB. In his paper, he also listed a number of candidate variables, but this star was not one of them. It has a nearby (within 5 arcsec) fainter companion 1-3-9 with V=17.84. We suspect that this star was not well resolved on all of the plates investigated by Gryzunova and this is why it appeared to be variable. In a more recent paper, Arellano Ferro (2008) applied the image subtraction technique to NGC 5466 and although they identified some new variables, they did not mention V22. We therefore conclude that V22 is not a variable star. V23: The period originally derived for this variable (0.2321607 days) by Gryzunova (1972) was unusally short and Cacciari (1974) showed that a period of 0.302353 days gave a perfectly equivalent light curve. The period listed in the above table (0.815) is from Corwin et al. (1999) who stated that Gryzunova's period did not produce a reasonable light curve, but commented that it was difficult to determine a period for this star. V26, V27: Corwin et al. (1999) investigated these two stars which they referred to as 4-1-22 (Cuffey's 1961 designation) and PV (the designation by Buonanno et al. 1984) and found that they did not appear to be variable. Both had nearby companions which were not resolved in some of the images and this probably caused their apparent variability. V31: The dominant frequency that Jeon et al. (2004) derived for this star corresponded to a period of 2.34 days, which they suggested might indicate that the variable is in an eclipsing system. ============================================================= Discovery of the variable stars in NGC 5466: V1-14 Baade (1926a) with x,y coordinates and an ID chart for V2-14. Baade (1926b) also announced 5 variables in the field around the cluster and listed RA and dec (epoch 1925) for them. V15-18 Sawyer (1945) with x,y coordinates, an ID chart and Hopmann (1927) catalogue numbers for V2-18 V19 = Star L Cuffey (1961) with an ID chart. He proposed that it be designated as V19 and Sawyer Hogg (1973) adopted this number in her 3rd catalog. This star was independently announced as SVS 1295 by Kurochkin (1961) who listed its 1900 RA and dec. It was subsequently included in the Moscow GCVS as BL Boo. It was also announced by Gryzunova (1969, 1972) who listed its x,y coordinates and designated it by its Hopmann number: 216. Zinn & Dahn (1976) gave a good discussion of the discovery of V19. They also showed that it is an anomalous Cepheid and a cluster member. V20-21 = Star 2-3-17 and 4-1-11 (both on the HB) Cuffey (1961) with ID chart. Sawyer Hogg derived their x,y coordinates for her 3rd (1973) catalog. Cuffey also found his star 3-5-2 to be variable and recommended that it be designated as V22. However, this star's position in the CM diagram (faint and red) is not consistent with cluster membership and it was therefore not included by Sawyer Hogg in her catalog. It was not detected as a variable in the subsequent studies by Buonanno et al. (1984) and Corwin et al. (1999). V22 = Hopmann 35 Gryzunova (1969, 1972) with Hopmann number and x,y coordinates. These coordinates were derived from Hopmann's (1922) x,y coordinates using corrections (Delta x = 21.8" and Delta y = 26.7") that he derived in a later paper (Hopmann 1927). The number V22 was assigned by Sawyer Hogg in her 3rd (1973) catalog. Corwin et al. (1999) could not locate a variable at the x,y coordinates reported by Gryzunova and Sawyer Hogg and V22 is now considered to be non-variable. See note above. V23 = Hopmann 235 = Cuffey 3-5-1 Gryzunova (1969, 1972) with Hopmann number and x,y coordinates. The number V23 was assigned by Sawyer Hogg in her 3rd (1973) catalog. Buonanno et al. (1984) detected variations in Cuffey's star 3-5-1 and derived x,y coordinates which were in good agreement with the ones derived by Gryzunova (1969) for Hopmann 235 (V23). Corwin et al. (1999) pointed out that they were the same star. V24-27 = Cuffey 2-3 17, 4-1-11, 4-1-22 and Buonanno PV Buonanno et al. (1984) with x,y coordinates and an ID chart. We assigned the numbers V24-V27 in our first on-line catalogue in 1998 without realizing that the stars that Sawyer Hogg (1973) listed as V20 and V21 in her 3rd catalog were Cuffey 2-3-17 and 4-1-11 respectively. Thus V24=V20 and V25=V21. Corwin et al. (1999) subsequently found that V26 and V27 were not variable. (See above in the "Notes on individual stars" section.) Buonanno et al. also noted that Cuffey's (1961) stars 3-4-20 and 3-4-21 might be variable but Corwin et al. (1999) did not detect any variability. V28-30 = blue stragglers NH19, NH30, NH31 Mateo et al. (1990) The NH numbers were labelled on a print published by Nemec & Harris (1987) V31-36 = blue stragglers NH29, NH49, NH35, NH27, NH39, NH38 identified on a print published by Nemec & Harris (1987) These stars were announced as variables by Nemec & Mateo (1990) and the numbers V31-V36 were assigned in our electronic editions of the GC variable star catalog, beginning in 1997. V37-38 Arellano Ferro et al. (2008) with an ID chart V39-41 = SXP 1, 2 and 3 Jeon et al. (2004) with RA & Dec and and an ID chart. The numbers V39-41 have been assigned in this catalogue. Jeon et al. also included V31-36 in their study, using the NH numbering system assigned by Nemec & Harris (1987). --------------------------- The 5 variables that Baade (1926b) discovered in the field around the cluster were subsequently studied by Kukarkin (1959) who published ID charts and by Gryzunova (1972) who derived periods. These 5 variables are listed in the Moscow GCVS as UW CVn, UV CVn, BI Boo, BN Boo and UU CVn respectively. Kukarkin (1959) commented that Baade F#3 (BI Boo) and Baade F#4 (BN Boo) are both possible cluster members. Kholopov (1962) noted that Baade F#5 (UU CVn) might also be a cluster member. F#3, F#4 and F#5 are all RR0 variables with periods of 0.5762165, 0.5196619 and 0.5409589 respectively. Kurochkin (1961) announced two variables in the corona of NGC 5466: SVS 1294 and 1295 which are listed in the GCVS as BK Boo and BL Boo respectively. BL Boo is the anomalous Cepheid, V19 and considered to be a cluster member. According to the GCVS, BK Boo might be a constant star. ======================================================================== References Arellano Ferro, A., Rojas Lopez, V., Giridhar, S., Bramich, D. M. 2008, MNRAS, 384, 1444 Baade, W. 1926a, Hamburg Mitt., 6, 27, 61 Baade, W. 1926b, Hamburg Mitt., 6, 27, 66 Buonanno, R., Buscema, G., Corsi, C. E., Iannicola, G., Fusi Pecci, F. 1984, A&A Suppl., 56, 79 Cacciari, C. 1974, IBVS, 905 Corwin, T. M., Carney, B. W., Nifong, B. G. 1999, AJ, 118, 2875 Cuffey, J. 1961, AJ, 66, 71 Gryzunova, T. I. 1969, Ast. Tsirk., 526, 8 Gryzunova, T. I. 1972, Per. Zvez. Pril., 1, 253 Hopmann, J. 1922, A.N., 217, 333 Hopmann, J. 1927, A.N., 229, 209 Jeon, Y.-B., Lee, M. G., Kim, S.-L., Lee, H. 2004, AJ, 128, 287 Kholopov, P. N. 1962, Per. Zvez., 14, 71 Kukarkin, B. V. 1959, Per. Zvez., 12, 50 Kurochkin, N. E. 1961, Per. Zvez., 13, 331 Mateo, M., Harris, H. C., Nemec, J., Olszewski, E. W. 1990, AJ, 100, 469 Nemec, J. M. & Harris, H. C. 1987, ApJ, 316, 172 Nemec, J. & Mateo, M. e 1990, ASP Conf., 11, 64 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. 1945, DDO Publ. 1, no. 17 Zinn, R. & Dahn, C. C. 1976, AJ, 81, 527 ======================================================================