Abstract
We present the theoretical analysis of the Al I line formation in the spectra of late-type stars ignoring the assumption of local thermodynamic equilibrium (LTE). The calculations were based on the 39-level aluminum atom model for one-dimensional hydrostatic stellar atmosphere models with the parameters: T eff from 4000 to 9000 K, log g = 0.0–4.5, and metallicity [A] = 0.0;–1.0;–2.0;–3.0;–4.0. The aluminum atom model and the method of calculations were tested by the study of line profiles in the solar spectrum. We refined the oscillator strengths and Van-der-Vaals broadening constants C 6 of the investigated transitions. We conclude that the Al I atom is in the overionization state: the 3p level is underpopulated in the line formation region. This leads to the line weakening, as compared with the LTE results. The overionization effect becomes more pronounced with increasing temperature and decreasing metallicity. We show that the use of various atomic data (ionization cross-sections) for the low levels of Al I does not change the behavior of non-LTE deviations, whereas the value of these deviations varies essentially. For nine selected Al I lines we calculated the grids of theoretical non-LTE corrections (ΔX NLTE = logɛ NLTE − log ɛ LTE) to the Al abundances determinedwith the LTE assumption. The non-LTE corrections are positive and significant for the stars with temperatures T eff > 6000 K. These corrections weakly depend on log g, and increase with declining stellar metallicity.
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Y. V. Pavlenko and A. Magazzu, Astronom. and Astrophys. 311, 961 (1996).
D. Kiselman, New Astron. Rev. 45, 559 (2001).
L. L. Mashonkina, V. V. Shimanskii, N. A. Sakhibullin, Astron. Rep. 44, 790 (2000).
N. N. Shimanskaya, L. L. Mashonkina, N. A. Sakhibullin, Astron. Rep. 44, 530 (2000).
N. Przybilla, K. Butler, S. R. Becker, and R. P. Kudritzki, Astronom. and Astrophys. 369, 1009 (2001).
J. R. Shi, T. Gehren, L. Mashonkina, and G. Zhao, Astronom. and Astrophys. 503, 533 (2009).
Y. Takeda, O. Hashimoto, H. Taguchi, et al., Publ. Astronom. Soc. Japan 57, 751 (2005).
L. Mashonkina, A. J. Korn, and N. Przybilla, Astronom. and Astrophys. 461, 261 (2007).
D. V. Ivanova and V. V. Shimanskii, Astron. Rep. 44, 376 (2000).
Ya. Pavlenko, M. R. Zapatero Osorio, and R. Rebolo, Astronom. and Astrophys. 355, 245 (2000).
E. V. Belyakova and L. I. Mashonkina, Astron. Rep. 41, 530 (1997).
L. I. Mashonkina and I. F. Bikmaev, Astron. Rep. 40, 94 (1996).
M. J. Seaton, C. J. Zeippen, J. A. Tully, et al., Rev. Mex. Astron. Astrofis. 23, 19 (1992).
T. Gehren, C. Reile, and W. Steenbock, Stellar Atmospheres BeyondClassicalModels (Kluwer, Dordrecht, 1991), p. 387.
D. Baumuller and T. Gehren, Astronom. and Astrophys. 307, 961 (1996).
D. Baumuller and T. Gehren, Astronom. and Astrophys. 325, 1088 (1997).
I. F. Bikmaev, T. A. Ryabchikova, H. Brunt, et al., Astronom. and Astrophys. 389, 537 (2002).
P. J. D. Mauas, R. F. Borda, and M. L. Luoni, Astrophys. J. Suppl. 142, 285 (2002).
T. Gehren, Y.C. Liang, J. R. Shi, et al., Astronom. and Astrophys. 413, 104 (2004).
L. Mashonkina, L. Zhao, T. Gehren, et al., Astronom. and Astrophys. 478, 529 (2008).
L. H. Auer and J. Heasley, Astrophys. J. 205, 165 (1976).
N. A. Sakhibullin, Trudi Kazansk. Gor. Astron. Obs. 48, 9 (1983).
Ya. V. Pavlenko, Doctoral Dissertation in Mathematics and Physics (GAO, Kiev, 1996).
S. E. Nersisyan, A. V. Shavrina, A. A. Yaremchuk, Astrophysics, 30, 147 (1989).
R. L. Kurucz, SAO CD-ROMs (MA02138, Cambridge, USA, 1994).
C. R. Vidal, J. Cooper, and E. W. Smith, Astrophys. J. 25, 37 (1973).
R. L. Kurucz and I. Furenlid, SAO Special Rep. 387, 1 (1979).
A. Unsold, Physik der Sternatmospheren (Springer, Berlin-Gottingen-Heidelberg, 1955).
F. Castelli and R. L. Kurucz, IAUS 210, A20 (2003).
V. F. Suleymanov, Astron. Astrophys. Trans. 2, 197 (1992).
N. Grevesse and A. J. Sauval, Space Sci. Rev. 85, 161 (1998).
J. H. Bruls, R. J. Rutten, and N. Shchukina, Astronom. and Astrophys. 265, 237 (1992).
L. I. Mashonkina, N. N. Shimanskaya, and V. V. Shimanskii, Odessa Astron. Publ. 9, 78 (1996).
A. A. Radzig, B. M. Smirnov, Parametri atomov i atomnikh ionov (Parameters of Atoms and Atom Ions (Energoatomizdat, Moscow, 1986) [in Russian].
E. Biemont and N. Grevesse, Atomic Data and Nuclear Data Tables 12, 217 (1973).
W. L. Wiese, M. W. Smith, and B. M. Miles, Atomic Transition Probabilities. II. Sodium through Calcium. A critical data compilation (NSRDS-NBS, Nat. Bur. Standarts, Washington, 1969).
J. L. Kohl and W. H. Parkinson, Astrophys. J. 184, 641 (1973).
D. G. Yakovlev, L. M. Band, M. B. Trzhaskovskaya, and D. A. Verner, Astronom. and Astrophys. 237, 267 (1990).
D. Hofsaess, Atomic Data and Nuclear Data Tables 24, 285 (1979).
C. Park, J. Quant, Spectrosc. Radiat. Transfer. 11, 7 (1971).
H. Van Regemorter, Astrophys. J. 132, 906 (1962).
L. A. Veinstein, I. I. Sobelman, E.A. Yukov, Vozbyzhdenie atomov i yshirenie spektralnih linii (Atom Excitation and Spectral Line Broadening (Nauka, Moscow, 1979) [in Russian].
J. I. Castor and H. Nussbaumer, Monthly Notices Roy. Astronom. Soc. 155, 293 (1972).
W. Lotz, Z. Physik 232, 101 (1970).
W. Steenbock and H. Holweger, Astronom. and Astrophys. 130, 319 (1984).
Y. Takeda, K. Kato, and Y. Watanabe, Publ.Astronom. Soc. Japan 48, 511 (1996).
C. Cowley, Observatory 91, 139 (1971).
R. L. Kurucz, I. Furenlid, J. Brault, and L. Testerman, Solar Flux Atlas from 296 to 1300 nm (Nat. Solar Obs., Sunspot, NewMexico, 1984).
V. S. Menzhevitski, V. V. Shimansky, N. N. Shimanskaya, Kinematics and Physics of Celestial Bodies 26, 210 (2009).
V. S. Menzhevitski, V. V. Shimansky, N. N. Shimanskaya, Uchenie Zapiski Kazan. State Univ. 153, 95 (2010).
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Original Russian Text © V.S. Menzhevitski, V.V. Shimansky, N.N. Shimanskaya, 2012, published in Astrofizicheskii Byulleten, 2012, Vol. 67, No. 3, pp. 308–323.
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Menzhevitski, V.S., Shimansky, V.V. & Shimanskaya, N.N. Non-LTE effects in Al I lines. Astrophys. Bull. 67, 294–309 (2012). https://doi.org/10.1134/S1990341312030066
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DOI: https://doi.org/10.1134/S1990341312030066