Abstract
We have used high-resolution spectra to study the chemical composition of HR 1512, a star with effective temperature T eff = 15 200 K, atmospheric gravity log g = 3.52, microturbulence parameter V t = 1.5 km/s, and rotation rate v sin i = 17 km s−1. We confirm the presence of a helium deficiency (−0.6 dex), indicating that HR 1512 is a helium-weak star. Its considerable phosphorus excess (1.6 dex) testifies that the star belongs to the PGa subtype. We suggest that the He and P abundances increase with height; i.e., that there is stratification of He and P in the star’s atmosphere. Among the CNO elements, nitrogen demonstrates an underabundance of −0.4 dex, while the abundances of carbon and oxygen are solar. Deficits of about −0.5 or −0.6 dex were also found for Mg, Si, and S. A neon excess of 0.4 dex was derived from our non-LTE analysis of NeI lines. The largest excess among the iron-peak elements (Cr, Mn, Fe, and Ni) is 0.6 dex, for manganese; the abundances of chromium and nickel display excesses of 0.5 and 0.3 dex, respectively, while the iron abundance is almost normal. The chemical anomalies of HR 1512 generally agree with those for mercury-manganese stars. This supports the hypothesis that PGa stars represent an extension of HgMn stars to higher temperatures.
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L. S. Lyubimkov, D. L. Lambert, T. M. Rachkovskaya, et al., Mon. Not. R. Astron. Soc. 316, 19 (2000).
L. S. Lyubimkov, T. M. Rachkovskaya, S. I. Rostopchin, and D. L. Lambert, Mon. Not. R. Astron. Soc. 333, 9 (2002).
L. S. Lyubimkov, S. I. Rostopchin, and D. L. Lambert, Mon. Not. R. Astron. Soc. 351, 745 (2004).
L. S. Lyubimkov, S. I. Rostopchin, T. M. Rachkovskaya, et al., Mon. Not. R. Astron. Soc. 358, 193 (2005).
D. Hoffleit and W. H. Warren, Jr., The Bright Star Catalogue, 5th ed. (ADS, Strasbourg, 1991); http://cdsweb.u-strasbg.fr/cgi-bin/Cat?v/50.
R. G. Tull, P. J. MacQueen, C. Sneden, and D. L. Lambert, Publ. Astron. Soc. Pac. 107, 251 (1995).
F. Kupka, N. E. Piskunov, T. A. Ryabchikova, et al., Astron. Astrophys., Suppl. Ser. 138, 119 (1999).
W. L. Wiese and J. R. Fuhr, NIST Atomic Spectra Database, Lines Data (1999); http://www.nist.gov/srd/atomic.htm.
R. Kurucz, ATLAS9 Stellar Atmosphere Programs and 2 km s −1 Grid, CD-ROM No. 13 (Smithsonian Astrophysical Observatory, Cambridge, MA, 1993).
A. Claret, Astron. Astrophys., Suppl. Ser. 109, 441 (1995).
L. S. Lyubimkov, Izv. Krymsk. Astrofiz. Obs. 62, 44 (1980).
J. R. Giddings, PhD Thesis (Univ. London, London, 1981).
K. Butler, http://ccp7.dur.ac.uk./Docs/detail.ps (1994).
K. Butler, PhD Thesis (Univ. London, London, 1984).
T. A. A. Sigut, Astrophys. J. 473, 452 (1996).
A. J. Korn, S. C. Keller, A. Kaufer, et al., Astron. Astrophys. 385, 143 (2002).
S. R. Becker and K. Butler, Astron. Astrophys. 201, 232 (1988).
S. A. Korotin, S. M. Andrievsky, and L. Yu. Kostynchuk, Astron. Astrophys. 342, 756 (1999).
S. A. Korotin, S. M. Andrievsky, and R. E. Luck, Astron. Astrophys. 351, 168 (1999).
N. Przybilla, K. Butler, S. R. Becker, and R. P. Kudritzki, Astron. Astrophys. 369, 1009 (2001).
L. H. Auer and D. Mihalas, Astrophys. J. 184, 151 (1973).
T. A. A. Sigut, Astrophys. J. 519, 303 (1999).
K. Lodders, Astrophys. J. 591, 1220 (2003).
Y. I. Izotov and T. X. Thuan, Astrophys. J. 602, 200 (2004).
M. R. Hartoog and A. P. Cowley, Astrophys. J. 228, 229 (1979).
L. W. Kamp, Astrophys. J., Suppl. Ser. 36, 143 (1978).
M. Vrancken, K. Butler, and S. R. Becker, Astron. Astrophys. 311, 661 (1996).
C. M. Jomaron, M. M. Dworetsky, and C. S. Allen, Mon. Not. R. Astron. Soc. 303, 555 (1999).
S. J. Adelman, Mon. Not. R. Astron. Soc. 239, 487 (1989).
M. Takada-Hidai, K. Sadakane, and J. Jugaku, Astrophys. J. 304, 425 (1986).
K. C. Smith, Astron. Astrophys. 305, 902 (1996).
K. C. Smith and M. M. Dworetsky, Astron. Astrophys. 274, 335 (1993).
K. C. Smith, Astron. Astrophys. 319, 928 (1997).
V. M. Woolf and D. L. Lambert, Astrophys. J. 521, 414 (1999).
C. R. Proffitt, T. Brage, D. S. Leckrone, et al., Astrophys. J. 512, 942 (1999).
S. J. Adelman and O. I. Pintado, Astron. Astrophys., Suppl. Ser. 125, 219 (1997).
S. W. Roby and D. L. Lambert, Astrophys. J., Suppl. Ser. 73, 67 (1990).
M. M. Dworetsky and J. Budaj, Mon. Not. R. Astron. Soc. 318, 1264 (2000).
O. Richard, G. Michaud, and J. Richer, Astrophys. J. 558, 377 (2001).
I. Savanov and S. Hubrig, Astron. Astrophys. 410, 299 (2003).
I. S. Savanov, O. P. Kochukhov, and V. V. Tsymbal, Astrofizika 44, 79 (2001) [Astrophys. 44, 64 (2001)].
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Original Russian Text © T.M. Rachkovskaya, L.S. Lyubimkov, S.I. Rostopchin, 2006, published in Astronomicheskiĭ Zhurnal, 2006, Vol. 83, No. 2, pp. 146–157.
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Rachkovskaya, T.M., Lyubimkov, L.S. & Rostopchin, S.I. The chemical composition of HR 1512, a peculiar helium-weak star. Astron. Rep. 50, 123–133 (2006). https://doi.org/10.1134/S1063772906020053
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DOI: https://doi.org/10.1134/S1063772906020053