NGC 6121 / Messier 4 / C1620-264 (Updated 2009) RA: 16:23:35.22 DEC: -26:31:32.7 (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 or P (for photographic). 61-65 A5 Type of variable (draft 2006 GCVS classifications) NV denotes not variable 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 16:23:13.68 -26:30:52.9 R0 0.2889 14.15 0.51 B RR1 2 16:23:16.31 -26:34:46.1 R0 0.5357 14.06 1.20 B RR0 3 16:23:19.49 -26:39:56.2 R0 0.5066 13.69 0.99 B RR0 4 16:23:21.07 -26:37:11.1 R0 ---- 10.0 0.5 V SR Note 5 16:23:21.00 -26:33:05.6 R0 0.6224 14.09 0.39 B RR0 6 16:23:25.80 -26:26:16.0 R0 0.3205 14.14 0.58 B RR1 7 16:23:25.96 -26:27:41.4 R0 0.4988 13.88 1.56 B RR0 8 16:23:26.18 -26:29:41.2 R0 0.5082 13.92 1.55 B RR0 9 16:23:26.81 -26:29:47.5 R0 0.5719 14.07 1.26 B RR0 10 16:23:29.22 -26:28:53.8 R0 0.4907 13.86 1.32 B RR0 11 16:23:30.01 -26:36:23.7 R0 0.4931 14.10 1.10 B RR0 12 16:23:30.82 -26:34:58.3 R0 0.4461 14.03 1.46 B RR0 13 16:23:30.93 -26:27:03.8 R0 ---- 10.95 0.5 V SR Note 14 16:23:31.31 -26:35:33.9 R0 0.4635 14.07 1.42 B RR0 15 16:23:31.98 -26:24:17.6 R0 0.4437 13.98 1.42 B RR0 16 16:23:32.52 -26:30:22.4 R0 0.5425 14.01 0.94 B RR0 17 16:23:34.02 -26:31:07.8 R0 0.8555 13.55 0.30 P RR? dS&O 18 16:23:34.69 -26:31:03.9 R0 0.4788 13.52 1.36 P RR0 dS&O 19 16:23:35.06 -26:25:36.1 R0 0.4678 13.89 1.46 B RR0 20 16:23:35.37 -26:32:35.8 R0 0.3094 13.42 0.36 P RR1 dS&O 21 16:23:35.92 -26:31:32.6 R0 0.4720 13.42 1.37 P RR0 dS&O 22 16:23:36.94 -26:30:12.5 R0 0.6031 13.69 0.58 P RR0 dS&O 23 16:23:37.34 -26:31:55.3 R0 0.2986 13.78 0.74 B RR1 24 16:23:38.04 -26:30:41.3 R0 0.5468 14.35 0.75 B RR0 25 16:23:39.44 -26:30:20.8 R0 0.6127 14.09 0.88 B RR0 26 16:23:41.67 -26:32:40.5 R0 0.5412 13.80 1.43 B RR0 27 16:23:43.19 -26:27:15.6 R0 0.6120 13.79 1.29 B RR0 28 16:23:53.62 -26:30:04.5 R0 0.5223 13.68 1.16 B RR0 29 16:23:58.27 -26:21:34.5 R0 0.5225 13.70 1.14 B RR0 30 16:23:59.67 -26:32:33.6 R0 0.2697 13.67 0.63 B RR1 31 16:24:00.66 -26:30:41.6 R0 0.5052 13.72 0.96 B RR0 32 16:24:29.71 -26:32:01.8 R0 0.5791 13.57 0.91 B RR0 33 16:24:33.36 -26:20:57.4 R0 0.6148 13.48 1.12 B RR0 34 16:22:33.65 -26:24:46.2 R0 0.5548 14.03 1.41 B RR0 35 16:23:06.62 -26:30:26.6 R0 0.6270 14.03 0.83 B RR0 36 16:23:19.52 -26:35:48.5 R0 0.5413 13.51 0.60 B RR0 37 16:23:31.62 -26:31:29.9 R0 0.2474 13.61 0.30 P RR1 dS&O 38 16:23:32.88 -26:33:03.0 R0 0.5778 14.22 0.68 B RR0 Note 39 16:23:34.69 -26:32:51.5 R0 0.6240 14.39 0.37 B RR0 40 16:23:36.49 -26:30:43.1 R0 0.4015 -- -- RR? dS&O 41 16:23:39.49 -26:33:59.3 R0 0.2517 14.10 0.40 B RR1 42 16:24:02.01 -26:22:12.7 R0 0.3037 14.00 0.88 B RR1 43 16:25:07.51 -26:25:43.4 R0 0.3206 13.42 0.63 B RR1 44 16:23:15.27 -26:31:17.9 R0 ---- 14.08 -- B RR? 45 16:23:37.35 -26:34:08.4 R0 ---- 14.35 -- B RR? 46 16:23:37.79 -26:34:00.9 R0 ---- 13.97 -- B RR? 47 16:23:37.34 -26:33:18.5 R0 ---- 14.20 -- B RR? 48 16:23:33.68 -26:32:00.0 R0 ---- 13.70 0.01 B NV? Note 49 16:23:45.24 -26:31:28.0 R0 0.216 13.65 0.3 B RR1 Note 50 16:23:37.55 -26:30:09.9 R0 ---- 13.60 -- B RR? 51 16:23:27.72 -26:33:06.1 R0 ---- 14.28 -- B RR? 52 16:23:24.08 -26:30:27.6 R0 0.4605 13.68 0.55 B RR0 Note 53 -283.4 -272.2 XA ---- 11.06 -- V RGtip;Note 54 99.3 123.6 XA ---- 12.67 -- V RG;Note 55 143.1 474.0 XA ---- 13.3 -- V blueHB;Note 56 139.9 -127.8 XA ---- 12.9 0.02 V RG;Note 57 -192.0 -27.1 XA ---- -- -- NV 58 165.9 -35.1 XA ---- 13.50 0.04 V blueHB;Note 59 196.4 -113.2 XA ---- 13.45 0.07 V redHB;Note 60 130.3 -145.8 XA ---- 13.46 0.03 V RG;Note 61 -76.2 +101.8 XA 0.2645 13.65 0.3 B RR1 Note 62=V55 63 16:23:20.91 -26:33:24.1 R0 0.2637 18.69 0.23 B EC max;Note 64 16:23:14.91 -26:30:18.3 R0 0.6033 20.67 1.20 B RR0 f;Note 65 16:23:47.07 -26:31:55.5 R0 0.0436 18.81 0.07 B ? max;f?;Note 66 16:23:25.42 -26:29:10.8 R0 0.2700 17.67 0.29 B EC max;Note 67 16:23:36.67 -26:31:43.1 R0 0.2825 17.12 0.22 B EC max;Note 68 16:23:34.21 -26:32:00.9 R0 0.2976 18.13 1.02 B EC max;f;Note 69 16:23:31.21 -26:31:47.5 R0 0.2665 18.00 0.44 B EC max;Note 70 16:23:33.08 -26:31:08.0 R0 0.3031 17.97 0.42 B EC max;Note 71 16:23:31.36 -26:30:56.8 R0 ---- 17.92 0.14 B ELL? max;f?;Note 72 16:23:38.37 -26:32:09.8 R0 0.3085 16.34 0.25 B EC max;Note 73 16:23:50.84 -26:34:41.1 R0 0.2526 18.67 0.32 B EC max;f?;Note 74 16:23:45.66 -26:31:15.6 R0 0.3108 17.51 0.49 B EC max;Note 75 -- -- 0.2973 14.25 0.3 B RR1 Note 76 -- -- 0.3058 14.3 0.6 B RR1 Note 77 16:23:34.17 -26:29:55.0 R0 ---- 14.70 0.10 V SR? max;Note 78 16:23:36.60 -26:31:49.6 R0 ---- 15.24 0.05 V SR? max;Note 79 -- -- ---- 15.05 0.3 V RG;Note 80 16:23:49 -26:23:52 R0 ---- 15.64 0.05 V f?;RG;Note ====================================================================== Supplementary Notes and References The RA & dec listed in the above table for V1-16, V18-19, V21-43, V44 (=Alc246), V45 (=Alc381) V46 (=Alc382), V47 (=Alc505), V48 (=Lee 1717), V49 (=Lee 3602), V50 (=Lee 3732), V51 (=Lee 1610), V52 (=Lee 2630) are from Shokin & Samus (1996, Ast Let 22, 761). The RA & dec for V17 and V20 are from Samus (2009 - private communication) Period, magnitude, amplitude and variability type for all RR Lyrae variables numbered from V1 to V43 are from Sujarkova & Shugarov (1981, Per. Zvez. 21, 505) unless designated as "dS&O" in the remarks column (see V17-18, V20-22, V37, V40). For these stars, this information is from de Sitter & Oosterhoff (1947, BAN 10, 287) Yao and collaborators have conducted numerous investigations of variable stars in and around M4. In the above table, we list only the ones that might be cluster members. Most of these variables are designated by their Greenstein (1939, ApJ 90, 401) numbers and Greenstein published an ID chart. Cudworth & Rees (1990, AJ 99, 1491) published an astrometric and photometric study of M4 based on PDS scans. They published x,y coordinates in arcsec for many of the variables listed by Yao, so we list their x,y coordinates. Kopacki is currently (2009) preparing a paper on the variables in M4. ================= Notes on individual stars V4: Eggen (1972, ApJ 172, 639) published magnitudes and plotted light curves for V4 and V13 based on photoelectric photometry. Both stars appear to be semi-regular variables. He derived P ~ 65 days for V4 and P ~ 40 days for V13. Kinman (1959, MNRAS 119, 157) derived a mean radial velocity 66 km/sec for M4 which is the same mean that Joy (1949, ApJ 110, 105) derived for these two variables. Therefore they are both considered to be cluster members. V13: See V4 V38: The y coordinate published by Sawyer Hogg (1973) for V38 is incorrect. It should be -92". This was a typing error; it was listed correctly in the 1955 edition of her catalog. V48=Lee1717: Lee 1717 = Greenstein 172. The mean V magnitude listed is from Lee's paper. Yao (1993, IBVS 3846) stated that this is a blue HB star and derived periods he considered to be preliminary because the amplitude is less than 0.01 V mag. V49 and V52: V49 = Lee 3602 = Greenstein 140 = ZB 19 V52 = Lee 2630 = Greenstein 37 = ZB 18 and Periods, mean magnitudes and amplitudes were published for these two stars by Yao (1979 Acta Ast Sin Vol 20, 398) with an English translation in (1980, Chinese Ast 4, 389). The period for V49 (Lee 3602) was later revised from 0.1958 to 0.216 by Yao (1987, ESO Messenger No. 50, 33). We note however, that this period is short for an RR Lyrae. V53 (G512): According to Table 1 of Alcaino (1975, A&A Supp 21, 5), Alcaino 219 = G512 and according to Cudworth & Rees (1990), Alcaino 219 = Lee 1411. The x,y cordinates listed for G512 are the ones Cudworth & Rees (1990) listed for Alcaino 219 (Lee 1411). The other information is from Yao (1981, Chinese A&A 5, 476). V54 (G30): According to Table 3 of Lee (1977), Lee 3621 (ZB38) = G30. The magnitude listed in the above table is from Yao (1981, Chinese A&A 5, 476). The x,y coordinates are the ones Cudworth & Rees (1990, AJ 99, 1491) listed for Alcaino 464 (Lee 3621). V55 (G327): Yao (1991, IBVS 3622) showed that the blue HB star G327 (ZB39) is Lee 3315 = Alcaino 64 and derived preliminary periods. The magnitude listed in the above table is from Yao (1981, Chinese A&A 5, 476). The x,y coordinates are the ones Cudworth & Rees (1990, AJ 99, 1491) listed for Alcaino 64 (Lee 3315). In our 2002 electronic catalog, we designated G327 as V55 and Alcaino 64 as V62, but they are the same star. V56, V58, V59, V60 (G265, G206, G481, G543): V magnitudes, amplitudes and location on the CM diagram are from Yao (1987, ESO Messenger No. 50, p 33). The x,y coordinates are the ones that Cudworth & Rees (1990) listed for Alcaino 375 (Lee 4508), Alcaino 491 (Lee 4632), Alcaino 371 (Lee 4512) and Alcaino 376 (Lee 4507) respectively. V61 (G46= Lee 2616): Yao (1988, Acta Ast Sin 29, 243) published a table that summarized the data for G46, as well as Lee 2630 (V52), Lee 3602 (V49), G343 (V75) and ZB14 (V76). The x,y coordinates we list for V61 are the ones Cudworth & Rees (1990, AJ 99, 1491) listed for Alcaino 440 (Lee 2616). V62: See note for V55. V63-V74 (V44-55 of Kaluzny et al. 1997): RA, dec, period, magnitude, amplitude, variability type and membership status from Kaluzny et al. (1997, AJ 113, 2219). The spectrum of V65 (V46 of Kaluzny et al. 1997, AJ 113, 2219) indicates that the star belongs to a composite system. In a more recent paper, Mochejska et al. (2002, AJ 124, 1486) pointed out that its spectrum is characteristic of a hot subdwarf, but its period is too long for that. Its light curve is consistent with an SXPhe classification, in which case, the star would be located behind the cluster. Rucinski (2000, AJ 120 p.319) investigated the membership status of the eclipsing binaries announced by Kaluzny et al. V75-76 (G343 and ZB14): Yao (1988, Acta Ast Sin 29, 243) published a table that summarized the data for these two stars, as well as Lee2630, Lee3602 and G46. V77-78: These stars are V56 and V57 of Mochejska et al. (2002, AJ 124, 1486). Both stars are on the RGB and the data listed in the above table are from their discovery paper. We have tentatively classified them both as semi-regular. V79 (G302): Mean V magnitude and amplitude for G302 are from Yao's 2004 discovery paper. Lee's published magnitude (1977, A&A Supp. 27, 367) was too bright because the star had an unresolved companion. Cudworth & Rees did not list an x,y position for this star in their 1990 paper (AJ 99, 1491). V80 (Alcaino 66): The information listed for this star in the table above is from the discovery paper by Yao et al. They also derived a period of approximately one day and concluded that the star must an eclipsing variable or a rotating spotted star if it is a cluster member. ====================================================================== Discovery of the Variable Stars in M4: V1-33 Leavitt (1904, HC 90, 1) with x,y positions An ID chart was subsequently published by Sawyer (1931, HC 366). The RA & dec listed in the above table are from Shokin & Samus (1996, Ast Let 22, 761). V34-43 de Sitter & Oosterhoff (1947, BAN 10, 287) with x,y positions for V34-43 and Greenstein's (1939, ApJ 90, 401) numbers for V35-42. Greenstein's paper included an ID chart. The RA & dec listed for these stars in the above table are from Shokin & Samus (1996, Ast Let 22, 761) who also published an ID chart for V34 and V43. V44-V47 are stars 246, 381, 382, and 505 listed by Alcaino (1975, A&A Suppl.21, 5) with ID chart. These are HB stars that Alcaino found to be variable He therefore classified them as RR Lyrae. Their status as variables has not been discussed in any subsequent studies. The B magnitudes we list in the above table are from his paper. The RA & dec are from Shokin & Samus (1996, Ast Let 22, 761). The numbers V44-47 were assigned in our electronic update to Sawyer Hogg's 1973 catalog. V48-V52 are stars 1717, 3602, 3732, 1610 and 2630 listed by Lee (1977, A&A Suppl. 27, 367) with ID chart. Lee stated that #1717, 3602 and 3732 are RR Lyrae variables and #1610 and 2630 were suspected RR Lyrae. The RA & dec listed in the above table for all of these stars are from Shokin & Samus (1996, Ast Let 22, 761). Lee 1717, 2630 and 3602 were subsequently observed by Yao. The B magnitudes we list for Lee 1610 and 3732 are from Lee's paper. Their status as variables has not been discussd in any subsequent studies. The numbers v48-52 were assigned in our electronic update to Sawyer Hogg's 1973 catalog. V53 = G512 = ZB44 V54 = G30 = ZB38 = Lee 3621 V55 = G327 = ZB39 = Lee 3315 = Alcaino 64 suspected variables announced by Yao et al. (1981, Chinese A&A 5, 476). The G numbers refer to Greenstein's 1939 paper (ApJ 90, 401) which includes an ID chart. ID charts were also published by Alcaino (1975, A&A Suppl. 21, 5) and by Lee (1977, A&A Suppl. 27 367). The numbers V53-55 were assigned in our electronic update to Sawyer Hogg's 1973 catalog. In our previous electronic catalog, Alcaino 64 and G327 (ZB39) were listed as separate variables (V55 and V62), but they are the same star. V56 = G265 = ZB37 = Alcaino 375 = Lee 4508 Yao, Astrophys & Space Sci 119, 41 (1986) This paper shows that at least one of the red giant stars G265 or G266 is variable, but in a subsequent paper in ESO Messenger (1987, No. 50, 33), it appears that only G265 is considered to be variable. The G number refers to Greenstein's 1939 paper (ApJ 90, 401) which includes an ID chart. ID charts were also published by Alcaino (1975, The number V56 was assigned in our electronic update to Sawyer Hogg's 1973 catalog. A&A Suppl. 21, 5) and by Lee (1977, A&A Suppl. 27 367). V57 = G266 = Lee 4509 This star was listed in our previous electronic catalog but it is no longer considered to be variable. See the comment above for G265. The number was assigned in our electronic update to Sawyer Hogg's 1973 catalog. V58 = G206 = Alcaino 491 = Lee 4632 V59 = G481 = Alcaino 371 = Lee 4512 V60 =G543 = Alcaino 376 = Lee 4507 Yao, ESO Messenger (1987, No. 50, 33) The G numbers refer to Greenstein's 1939 paper (ApJ 90, 401) which includes an ID chart. ID charts were also published by Alcaino (1975, A&A Suppl. 21, 5) and by Lee (1977, A&A Suppl. 27 367). The numbers V58-60 were assigned in our electronic update to Sawyer Hogg's 1973 catalog. V61 = G46 = Alcaino 149 = Lee 2616 Yao (1988, Acta Ast Sinica 29, No. 3, p243) with ID chart and x,y position. The x,y we list in the above table is the value Cudworth & Rees (1990, AJ 99, 1491) listed for Lee 2616. The G number refers to Greenstein's 1939 paper (ApJ 90, 401) which includes an ID chart. ID charts were also published by Alcaino (1975, A&A Suppl. 21, 5) and by Lee (1977, A&A Suppl. 27 367). The number V61 was assigned in our electronic update to Sawyer Hogg's 1973 catalog. V62 = Alcaino 64 which is the same star as V55. The number V62 was assigned in our electronic update to Sawyer Hogg's 1973 catalog. V63-V74 are V44-V55 of Kaluzny et al. (1997, AJ 113 2219) with ID charts and 1950 RA and dec. The 2000 RA and dec listed in the above table are from Kopacki (2009 private communication) who is preparing a paper on the variables in M4. The numbers V63-V74 were assigned in our electronic update to Sawyer Hogg's 1973 catalog. V75 = G343 = ZB36 Yao (1979, Chinese Astronomical Circular No. 6) with x,y position and ID chart. The G number refers to Greenstein's 1939 paper (ApJ 90, 401) which also includes an ID chart. We have not listed Yao's x,y coordinates [-581, +384] in the above table because they are on a different system from those of Cudworth & Rees, which we have listed for the other variable stars discovered by Yao and collaborators. V76 = ZB14 Yao (1977, Acta Ast Sin 18, 216) and English translation in (1978 Chinese Ast 2, 305) with x,y position and ID chart. ZB is the abbreviation for Zhongguo Bianxing (Chinese Variable Star). We have not listed Yao's x,y coordinates [-1198, +590] in the above table because they are on a different system from those of Cudworth & Rees, which we have listed for the other variable stars discovered by Yao and collaborators. V77-78 = variables numbered 56 and 57 of Mochejska et al. Mochejska et al. (2002, AJ 124, 1486) with RA, dec and ID charts V79 = G302 = Lee 3107 Yao et al. (2004, Acta Ast Sinica 45, 237) and English translation in (2004, Chinese A&A 28, 399) with ID chart The G number refers to Greenstein's 1939 paper (ApJ 90, 401) which includes an ID chart. V80 = Alcaino 66 Yao et al. (2006, Chinese A&A 30, 351) which is an English translation of (2007, Acta Ast 48, 18) with RA and dec. Alcaino (1975, A&A Supp. 21, 5) published an ID chart. Pietrukowicz et al. (2008, MNRAS 388, 1111) searched for dwarf novae in M4 and found none. ==============================================================