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1994Aj 107.2184E the Astronomical Journal THE ASTRONOMICAL JOURNAL VOLUME 107, NUMBER 6 JUNE 1994 107.2184E PHOTOMETRY OF F-K TYPE BRIGHT GIANTS AND SUPERGIANTS. III. THE LUMINOSITY, REDDENING, AND HEAVY ELEMENT ABUNDANCE OF GK STARS Olin J. Eggen 1994AJ Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatories,1 Casilla 603, La Serena, Chile Received 1993 December 7; revised 1994 January 31 ABSTRACT The reddening, luminosity, and heavy element abundance of 250 bright giants and supergiants of type GK are discussed on the basis of 4 color, DDO, RI, and Geneva photometry. Bright giants of type GK with age greater than 5X108 yr, and of type GO/3 with age greater than 2X108 yr, are very scarce in the solar neighborhood. The median space motion vectors of the bright giants and supergiants with well determined space motions are (£/,V,JV) = (+10.6,—13.2,-7.7)±(12.3,8.8,8.8) km/s. The index for 4 color photometry, when corrected for luminosity (gravity) effects, is sensitive to heavy element abundance in the F type stars but not in those of GK type. The CN index reflects the heavy element abundance of the GK stars but may not be reliable for those of type GO/3. The available spectroscopic determinations of [Fe/H] give mixed results with the two largest samples [McWilliam, ApJS, 74,1075 (1990); Brown et ö/., ApJS, 71, 293 (1989)] being internally consistent but with a large zero-point difference. There is a similar zero-point shift in the peak frequency of the photometrically determined values of P[Fe/H] for the F type and for the GK type stars. There is little evidence for an appreciable galactic, radial gradient in the P[Fe/H] values. A previously noted correlation of the heavy element abundance index, AMj, with the amplitude defect in the B light curves of Cepheids, FB, and interpretation of the (PLFB) relation as a (PL [Fe/H]) relation needs further investigation in light of the apparent sensitivity of M1 to Fe/H for the F stars (the domain of the Cepheids with P<10 d) and lack of this sensitivity for the G0/3 star (domain of the Cepheids with P>10 d). 1. INTRODUCTION P[Fe/H](M1)=3.2A(M1)0+0.100, (7) The normal (class III) giants of types G and K in the where young disk population are extensively discussed in Eggen (1993) on the basis of the following calibrations: reddening; ACN=(Cm)0-1.112(Ä-/)0 + 0.131, (8) (¿>-y)o=0.826(P-/) + 0.722M1-0.550(b-y) A(M1)o=(M1)o-2.15(/?-/)o + 0.240. (9) + 0.353, (1) The (b—y), M,, C¡ and (R,I) systems are defined in Eggen luminosity; (1982) and the DDO system in McClure (1976). As noted in Eggen (1993) the bright giants (BG) and su- A/V=4.86(C1) —5.86(P—/)0 + 0.95, (2) pergiants (SG) require a different calibration of the photo- metric parameters in terms of luminosity and reddening. The where C1 = C1-0.220(b—y), adopted relations are: My=6.60 —13.00(P—/)0 —20.00A(45 —48)0 E(b—y) = 1.085(1?—/) —0.603[(42 —45) — 3.12(CJ0, (3) — 5(45 —48)]+ 0.151, (10) where where A(45 — 48)0= (45 —48)0 —0.600(42 —45 )0“ 0.605, (4) 5(45 —48) = (45 —48) —0.600(42 —45) —0.695, (11) (Cm)0=(41—42)0—1.66[(45 —58)0 — 0.45(42 —45)0 Aiy(DDO) = 3.43 —14.00(1?—/)0 —20.05(45 -0.792], (5) — 48) for (f?-/) =£0.375, heavy element abundance; 0 0 P[Fe/H](DDO)=3.12ACN+0.031, (6) A/V(DDO) = 1.75 — 9.50(1?—/)0 —20.05(45 — 48)0 for (l?-/)0^0.375, (12) 1Operated by the Association of Universities for Research in Astronomy, Inc. under cooperative agreement with the National Science Foundation. My(4C) = 2.75 —10.50(1?—/)0—7.65[« —6], (13) 2184 Astron. J. 107 (6), June 1994 0004-6256/94/107(6)/2184/27/$0.90 © 1994 Am. Astron. Soc. 2184 © American Astronomical Society • Provided by the NASA Astrophysics Data System 2185 O. J. EGGEN: GK GIANTS AND SUPERGIANTS 2185 107.2184E Table 1. (R-I) photometry. 1994AJ HD R-I HD R-I HD R-I 3488 5?97 0®352 65699 4,?62 0*?345 0 2 97534 4®00 0I?347 6446 6.55 0.528 66604 9.08 0.362 0 2 98386 6.77 0.457 0 7927 4.67 0.385 66678 8.88 0.322 2 2 96782 7.74 0.359 4 8267 7.64 0.345 67243A 5.67 0.359 5 3 99154 7.90 0.334 3 12409 8.43 0.309 67243C 10.46 0.770 15 2 99313 7.91 0.395 2 13640 8.30 0.424 67523 2.66 0.079 1 99576 8.46 0.462 1 14985 6.25 0.453 67594 3.94 0.314 5 2 100137 7.46 0.380 1 15589 6.48 0.384 66111 7.66 0.405 7 2 100276 7.35 0.268 1 16901 5.05 0.310 70046 6.44 0.414 2 3 101314 6.70 0.374 5 17005 6.40 0.260 70302 5.79 0.355 0 2 101570 4.46 0.400 2 18145 6.03 0.348 70385 7.22 0.404 2 2 102305 8.42 0.371 0 20902 0.214 70555 4.20 0.490 1 2 102839 4.33 0.475 2 20176 5.77 0.350 71181 7.06 0.403 2 2 103134 9.07 0.356 1 23010 6.39 0.088 72125 7.72 0.459 2 2 103225A 7.26 0.457 4 24107 7.02 0.360 72561 5.52 0.353 4 2 104096 8.71 0.469 4 25049 6.73 0.391 73155 4.42 0.455 0 2 104215 7.13 0.485 2 26630 0.383 74160 3.32 0.359 1 105136 5.72 0.409 6 27385 6.64 0.596 75276 5.46 0.275 5 2 105340 4.53 0.466 5 28085 6.63 0.474 75586 7.74 0.374 4 2 106057 5.15 0.300 2 28794 5.36 0.455 76006 6.97 0.290 4 2 106981 7.05 0.440 4 31767 3.87 0.460 77020 5.39 0.353 4 2 107265 7.19 0.441 5 31910 0.310 77615 5.23 0.445 5 3 106262 7.55 0.369 38871 4.86 0.305 77996 4.94 0.427 3 4 110463 6.09 0.344 1 39400 4.18 0.481 78791 4.25 0.302 3 2 111315 5.05 0.369 5 40805 3.52 0.375 79696 5.20 0.269 6 3 111790 5.78 0.356 1 41701 6.16 0.281 79737 6.80 0.533 7 2 112762 7.62 0.493 2 42456 6.94 0.470 79739 6.36 0 446 4 2 113778 5.12 0.336 43497 7.20 0.528 80106 4.25 0.616 2 2 114533 5.41 0.356 2 44612 6.51 0.340 80126 6.74 0.391 4 2 114756 6.61 0.506 2 45416 4.74 0.380 61502 5.56 0.495 3 2 117341 7.99 0.341 0 45629 5.94 0.469 61949 6.42 0.350 2 2 117740 3.38 0.391 47209 6.59 0.306 82122 6.93 0.346 7 2 116520 5.56 0.393 2 47475 5.84 0.360 62150 3.90 0.500 4 3 119605 5.24 0.265 4 47667 4.16 0.535 82205 4.68 0.462 5 2 120112 7.00 0.456 2 48616 6.36 0.359 62415 6.07 0.289 2 2 120537 6.19 0.436 0 49050 7.16 0.525 83111 6.50 0.363 3 2 121261 8.67 0.512 5 49068 6.66 0.440 83609 7.66 0.268 2 2 121976 7.43 0.364 0 49091 6.13 0.555 63657 7.35 0.396 0 2 122223 4.18 0.204 49102 7.16 0.391 63696 8.32 0.418 4 2 123349 7.94 0.447 0 49105 7.34 0.405 84341 8.05 0.487 7 2 124196 6.05 0.362 0 49212 7.30 0.400 84441 2.70 0.275 5 2 124602 7.62 0.499 2 49367 6.76 0.391 84533 6.06 0.530 2 2 125609 5.90 0.404 3 49778 6.64 0.353 84610 7.42 0.303 0 2 126152 7.27 0.661 5 50372 6.65 0.355 85205 7.96 0.328 1 2 127685 6.61 0.485 1 51043 6.00 0.345 85530 7.48 0.376 2 2 128713 5.75 0.396 3 52497 4.88 0.312 85656 4.93 0.441 5 2 129330 6.79 0.396 2 53003 6.64 0.281 86453 6.84 0.263 1 2 131296 5.12 0.436 1 54605 1.70 0.195 87109 7.14 0.412 1 2 131425 5.45 0.356 0 55751 4.65 0.400 87323 7.00 0 350 6 2 132223 7.51 0.391 2 56695 8.98 0.343 87951 6.36 0.333 1 2 132242 6.22 0.211 57118 5.89 0.277 86056 7.99 0.302 0 2 132594 7.59 0.366 57623 3.70 0.253 88069 7.86 0.300 4 4 134270 4.96 0.306: 58134 7.15 0.359 88092 7.30 0.283 3 3 134704 7.50 0.324 58367 4.59 0.335 88495 8.08 0.307 4 2 135551 7.70 0.362 58526 5.60 0.310 88756 7.26 0.449 2 2 135913 7.80 0.326 59367 8.13 0.382 89175 7.47 0.343 2 2 136474 7.36 0.409 54669 5.76 0.375 89716 7.36 0.343 2 2 136505 6.14 0.376 59890 4.90 0.300 89373 7.46 0.456 5 2 136537 6.27 0.409 61561 8.92 0.347 89805 5.54 0.547 5 2 136635 10.33 219 61714 7.43 0.328 89874 7.30 0.291 0 2 136636 8.19 374 62236 7.52 0.369 89925 6.90 0.298 2 2 137465 5.62 338 63609 7.86 0.346 90301 7.86 0.274 0 2 141120 7.06 416 63700 2.37 0.370 90772 4.46 0.247 1 141767 4.61 391 63822 5.59 0.413 91629 7.12 0.259 0 2 142277 7.15 0.390 18.2032 9.48 0.357 92449 3.87 0.322 4 2 142584 6.68 0.442 64320 6.13 0.434 93807 6.54 0.416 2 2 142811 8.52 0.464 64571 6.27 0.263 94584 8.05 0.445 1 2 142822 6.70 0.487 64572 4.95 0.356 95393 6.64 0.482 2 2 143084 5.75 0.556 64858 8.11 0.344 96544 5.48 0.426 6 3 143119 6.77 0.500 65228 3.95 0.236 96746 8.39 0.318 0 2 144338 6.30 0.512 65297 7.24 0.447 97189 7.78 0.422 2 2 145302 9.10 0.386 © American Astronomical Society • Provided by the NASA Astrophysics Data System 2186 O.
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