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Publications of the Astronomical Society of the Pacific 106: 382-396, 1994 April Publications of the Astronomical Society of the Pacific 106: 382-396, 1994 April An Atlas of Southern MK Standards From 5800 to 10,200 A1 Anthony C. Danks Hughes STX/Goddard Space Flight Center, Code 683.0, Greenbelt, Maryland 20771 Michel Dennefeld Institut d'Astrophysique, 98bis Boulevard Arago, F-75014 Paris, France Received 1992 December 30; accepted 1994 February 2 ABSTRACT. An atlas of stellar spectra covering the wavelength range from 5800 to 10,200 A is presented of 126 southern MK standard stars, covering the luminosity classes I, III, and V. Some peculiar stars are included for comparison purposes. The spectra were obtained at a resolution of 4.3 A per pixel using a Cassegrain-mounted Boiler and Chivens spectrograph equipped with a Reticon detector. The quality and utility of the data are discussed and examples of the spectra are presented. The atlas is available in digital format through the NSSDC. 1. INTRODUCTION tion of 15 A which is lower than that used in this atlas, but overlaps nicely in wavelength. Mantegazza (1992) has be- Spectral synthesis of galaxies is one of the major driving forces for producing new stellar libraries covering as large gun the work of extending calibration to the Magellanic a spectral interval as possible. The "photographic" wave- clouds by observing 34 LMC and 15 SMC supergiants be- length region from 3800 to 4800 A, initially used for the tween AO and G5 in the wavelength range from 5600 to MK classification scheme, has been extended to shorter 9000 A, interestingly made with the same spectrograph as wavelengths through space technology. The UV range has this study. Origlia et al. (1993) have recently produced a been included in the classification schemes thanks to con- list of G, K, and M stars in the 1.5-1.7 μιη region for siderable efforts made by, e.g., Rountree and Sonneborn synthesis of NGC 1068. Our atlas bridges the gap between (1991), Massa (1989), Walbom and Nichols-Bohlin visible and IR nicely at a reasonable spectral resolution. A (1987), Walborn et al. (1985), Wu et al. (1983, 1991), detailed review of recent stellar spectral libraries can be and Heck (1982). found in Bica (1991). As spectral synthesis approaches improve, it has become Our intent in this paper is to augment the spectral li- clear that multiple stellar populations are needed, includ- braries available in the near infrared and provide as high a ing older and/or cooler stellar components, and this in spectral resolution possible without compromising flux turn is driving the need for red to near-infrared stellar considerations. The Cassegrain-mounted Boiler and Chiv- spectra. ens spectrograph with its high resolution-luminosity prod- With advances in detector technology (specially for sil- uct, equipped with a cooled Reticon diode array was an icon devices) observations can now routinely be made into ideal combination for this work. The observations were the near infrared, from the ground. The work of Jacoby et carried out at ESO, Chile. The initial intent was to select al. ( 1984) is an example of one of the first extensions into the wavelength range to start at 5000 A just longward of the red, with a library of 161 stellar spectra covering the the traditional MK spectral range and extend the spectral wavelength region 3150 to 7427 A at a spectral resolution coverage as far as possible into the red with one grating ~4.5 A. Similarly, Faber et al. (1985) studied 110 gi- Κ setting. However, by starting instead at 5800 A just short- ants and subgiants at a resolution of 9 A over the wave- ward of the Nai lines, we could take advantage of the length range 4000 to 6200 A. More recently, Silva and Cornell (1992) have studied stars from 3510 to 8930 A. Reticon red sensitivity out to 10,200 A. This combination For the near infrared, data available in the literature are gives approximately an additional 4000 A of spectrum to fragmentary and of varying quality, e.g., treating specific the usual visible range and should be particularly useful for spectral types, Fawley ( 1977), Barbieri et al. ( 1981 ), Jones stellar population synthesis studies of elliptical galaxies, et al. (1984), Alloin and Bica (1989), and Kirkpatrick et especially because their major constituents appear to be al. ( 1991, 1993). Many studies have been designed for flux late-type stars (O'Connell 1980). A first step was naturally calibration purposes and therefore of necessity low resolu- to obtain a set of standard stars to extend the spectral tion, e.g., O'Connell (1973), Breger (1976), Cochran classification to this region and to serve as a reference for (1981), Cochran and Barnes (1983), Gunn and Stryker comparison with other objects. The 126 stars presented in (1983). Recently, Torres-Dodgen and Weaver (1993) this paper were chosen from a master list of MK standards have published a digital near-IR atlas of 57 northern stars provided by the Stellar Data Center in Strasbourg. The in the wavelength region from 5700 to 8900 A at a resolu- number of MK standards in the Southern Hemisphere is limited, and our selection was made in consultation with C. ^ased on observations obtained at the European Southern Observatory, Jaschek. The complete list of stars, spectral type, luminos- La Silla, Chile. ities, magnitudes, and positions is given in Table 1. The 382 © 1994. Astronomical Society of the Pacific © Astronomical Society of the Pacific · Provided by the NASA Astrophysics Data System ATLAS OF SOUTHERN MK STANDARDS FROM 5800 TO 10,200 A 383 Table 1 Name, Spectral Type, Luminosity Class, Position, Magnitude, and Colors for the Stars Observed cu Spectral Type/L HD Number Spectral Type/L Real Name a (2000) 8 O-Type HD 200499 A5 V 22 CAP 21 0424.2 -1951 18 4.84 +.17 HD 66811 05 laf ζ PUP 08 03 35.0 -40 00 11 2.25 HD 187642 A7V 53 α AQL 19 50 46.9 +08 52 06 0.77 +.22 HD 37742 OS Ibe 50 ζ ORI 05 40 45.5 -01 56 34 2.05 -.21 HD 88824 A7 V 10 13 22.8 -51 13 59 5.28 +.25 HD 57061 091b 30 τ CMa 07 18 42.4 -24 57 15 4.40 -.15 F-Type HD 37043 09 III 44 ι ORI 05 35 25.9 -05 54 36 2.77 -.24 HD 36673 FOIb 05 32 43.7 -17 49 20 2.58 HD 47839 07 Ve 15 MON 06 40 58.6 +09 53 44 4.66 -.25 HD 90772 FOI 10 27 24.4 -57 38 20 4.66 HD 37468 09.5 V 48 σ ORI 05 38 44.7 -02 36 00 3.81 -.24 HD 161471 F2 la 17 47 35.0 -40 07 37 3.03 B-Type HD 61715 F4 lab 07 38 18.2 -48 36 04 5.68 HD 38771 BO.5 lav 53 κ ORI 05 47 45.3 -09 40 11 2.06 HD 54605 F8 la 25 δ CMA 07 08 23.4 -26 23 35 1.84 HD 53138 B3 la 24 o2 CMA 07 03 01.4 -23 50 00 3.02 HD 38558 FOUI 130 TAU 05 47 26.1 +17 43 45 5.49 +.30 HD 58350 31 η CMA 07 24 05.6 -29 18 11 2.45 HD 13174 F2 III 14 ARI 02 09 25.3 +25 56 24 4.98 +.33 HD 164353 67 ΟΡΗ 18 00 38.6 +02 55 53 3.97 HD 164584 F3 III 7 SGR 18 02 51.0 -24 16 56 5.34 +.52 HD 34085 81 19 β ORI 05 14 32.2 -08 12 06 0.12 HD 27290 F4 III γ DOR 04 1601.6 -51 29 12 4.25 +.30 HD 44743 B1 III 2 β CMA 06 22 41.9 -17 57 22 HD 48737 F5 III 31 ξ GEM 06 45 17.3 + 1253 44 3.36 HD 52089 B2 II 21 ε CMA 06 58 37.5 -28 50 20 HD 196524 F5 III 6 β DEL 20 37 32.9 + 14 35 43 3.63 HD 51309 B3 II 20 t CMA 06 56 08.1 -1703 15 4.37 HD 217096 F8 III-IV 22 58 34.9 -35 31 24 6.13 HD 53244 B8II 27 γ CMA 07 03 45.5 -15 38 00 4.12 HD 220657 F8 III 68 υ PEG 23 25 22.7 +23 24 15 4.40 HD 30836 B2III 3 π4 ORI 04 51 12.3 +05 36 18 3.69 HD 17094 F0IV 87 μ CET 02 44 56.5 + 10 06 51 4.27 HD 35468 B2 III 24 γ ORI 05 25 07.8 +06 20 59 1.64 HD 27397 F0IV 57 TAU 04 19 57.6 + 14 02 07 5.59 HD 34503 B5 III 20 τ ORI 05 17 36.3 -06 50 40 3.60 HD 182640 F3 IV 30 δ AQL 19 25 29.8 +03 06 53 3.36 HD 36822 B0 III 37 01 ORI 05 34 49.2 +09 29 22 4.41 -.16 HD 216385 F7IV 49 σ PEG 22 52 24.0 +09 50 09 5.16 HD 147165 B2 III + 09.5 V 20 σ SCO 1621 11.2 -25 35 34 2.89 +.13 HD 29992 FI V β CAE 04 42 3.4 -37 08 40 5.05 +.37 HD 886 B2 IV 88 γ PEG 00 13 14.1 +15 11 01 2.83 HD 26690 F2 V + F5 V 46 TAU 04 13 33.0 +07 42 58 5.29 +.36 HD 143018 B1 V + B2 V 6 π SCO 15 58 51.0 -26 06 51 2.89 HD 30652 F6V π3 ORI 04 49 50.3 +06 57 41 3.19 HD 16582 B2 IV 82 δ CET 02 39 28.9 +00 19 43 4.07 HD 173667 F6V 110 HER 18 45 39 +20 33 00 4.20 HD 23302 B6 IV 17 TAU 03 44 52.2 +24 06 48 3.70 HD 222368 F7V 17 ι PSC 23 39 57.0 +05 37 35 4.13 +.51 HD 23630 B7 IV 25 η TAU 03 47 29.0 +24 06 18 2.87 HD 1581 F9V ζ TUC 00 20 04.2 -64 52 30 4.23 +.58 HD 23850 B8 IV 27 TAU 03 49 09.7 +24 03 12 3.63 -.09 G-Type HD 35411 B0.5 V 28 η ORI 05 24 29 -02 23 00 3.35 -.19 HD 204867 GO Ib 22 β AQR 21 31 33.4 -05 34 16 2.91 HD 149438 B0V 23 τ SCO 16 35 53 -28 13 00 2.82 +.26 1 HD 52220 G1 Ib 06 58 56.3 -32 43 14 6.91 HD 144470 81 V 9 ω SCO 16 06 48 -20 40 00 3.95 -.04 HD 209750 G2 Ib 34 α AQR 22 05 46.9 -00 19 11 2.96 HD 74280 B3 V 7 η HYA 08 43 14 +03 23 00 4.30 -.20 HD 44362 G2 Ib 06 18 46.8 -50 21 33 7.04 +.83 HD 208057 B3 V 16 PEG 21 530 4 +25 55 00 5.07 HD 206859 G5 Ib 9 PEG 21 44 30.6 + 17 21 00 4.34 + 1.17 HD 219688 B5 V 93 Ψ AQR 23 17 54.1 -09 10 57 4.39 HD 48329 G8 Ib 27 ε GEM 06 43 55.9 +25 07 52 2.98 + 1.40 HD 58715 B8 V 3 β CMI 07 27 09.0 +08 17 21 2.90 HD 36079 G5 II 9 β LEP 05 28 14.7 -20 45 34 2.84 +.82 HD 214923 B8 V 42 ζ PEG 22 41 27.6 + 10 49 53 3.40 HD 185758 G1 III 5 α SEG 19 40 05.7 + 18 00 50 4.37 +.78 HD 218045 B9 V 54 α PEG 23 04 45.6 +15 12 19 2.49 HD 21120 G6 III 1 o TAU 03 24 48.7 +09 01 44 3.60 +.89 A-Type HD 33833 G7 III 05 12 48.1 -06 03 26 5.91 +.96 HD 46300 AO lb 06 32 54.2 +07 19 58 4.50 +.00 HD 10761 G8 III 110 o PSC 01 45 23.6 +09 09 28 4.26 +.96 HD 59612 A5 lb 08 29 51.4 -23 01 28 4.85 +.23 HD 3919 G8 III μ PHE 00 41 19.5 -46 05 06 4.59 +.97 HD 43836 AO II 6 19 22.7 23 16 37 7.03 HD 184492 G9 III 37 μ AQL 19 35 07.2 -10 33 38 5.12 + 1.13
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