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Estimating the chromospheric magnetic field from a revised NLTE modeling: the case of HR 7428

Published online by Cambridge University Press:  12 September 2017

Innocenza Busá*
Affiliation:
INAF - Catania Astrophysical Observatory, Via S. Sofia, 78, 95123 - Catania - Italy email: [email protected]
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Abstract

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Semi-empirical atmospheric modeling is here used to obtain the chromospheric magnetic field distribution versus height in the K2 primary component of the RS CVn binary system HR 7428. The chromospheric magnetic field estimation versus height comes from considering the possibility of not imposing hydrostatic equilibrium in the atmospheric modeling. The stability of the best Non-hydrostatic equilibrium model, implies the presence of and additive (toward the center of the star) pressure, that decrease in strength from the base of the chromosphere toward the outer layers. Interpreting the additive pressure as magnetic pressure and I derive a magnetic field intensity of about 500 Gauss at the base of the chromosphere.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2017 

References

Andretta, V., Busá, I., Gomez, M. T., & Terranegra, L. 2005 Astronomy & Astrophysics, 430, 669 CrossRefGoogle Scholar
Byrne, P. B., Abdul Aziz, H., Amado, P. J., et al. 1998 A&AS, 127, 505 Google Scholar
Brown, A. et al. 1991 Astrophysical Journal, 373, 614B Google Scholar
Busá, I., Andretta, V., Gomez, M. T., & Terranegra, L. 2001 Astronomy & Astrophysics, 373, 993 CrossRefGoogle Scholar
Carlsson, M. 1986, Technical report 33, Uppsala Astronomical Observatory Google Scholar
Cram, L. E. & Mullan, D. J. 1979, Astrophysical Journal, 234, 579 Google Scholar
Fontenla, J. M., Avrett, E. H., & Loeser, R. 1993, Astrophysical Journal, 406, 319 Google Scholar
Gratton, L. 1950, Astrophysical Journal, 111, 31 Google Scholar
Griffiths, N. W. & Jordan, C. 1998, Astrophysical Journal, 497, 883 Google Scholar
Jordan, C. & Brown, A. 1981 SPSS, 199JCrossRefGoogle Scholar
Hall, D. S., Gessner, S. E., Lines, H. C., & Lines, R. D. 1990 Astronomical Journal, 100, 2017 Google Scholar
Harper, G. M. 1992 Monthly Notices of the Royal Astronomical Society, 256, 37 Google Scholar
Houdebine, E. R. 1996 IAUS, 176, 547H Google Scholar
Kalkofen, W., Ulmschneider, P., & Avrett, E. H. 1999 Astrophysical Journal, 521, 141 CrossRefGoogle Scholar
Kurucz, R. L. 1993, IAU Coll. 138, ASP Conf. Ser., 44, 87 Google Scholar
Kurucz, R. L. & Avrett, E. H. 1981, SAOSR, 391Google Scholar
Leone, F., Avila, G., Bellassai, G., et al., 2016, AJ, 151, 116L CrossRefGoogle Scholar
Marino, G., Catalano, S., Frasca, A., & Marilli, E. 2001, Astronomy & Astrophysics, 375, 100 Google Scholar
Mauas, P. J. D. & Falchi, A. 1994, Astronomy & Astrophysics, 281, 129 Google Scholar
Mauas, P. J. D., Falchi, A., Pasquini, L., & Pallavicini, R. 1997, Astronomy & Astrophysics, 326, 249 Google Scholar
Mauas, P. J. D., Cacciari, C., & Pasquini, L. 2006, Astronomy & Astrophysics, 454, 609 Google Scholar
Cram, L. E. & Mullan, D. J. 1979, Astrophysical Journal, 234, 579 Google Scholar
Parsons, S. B. & Ake, T. B. 1987, Bull. Am. Astron. Soc., 19, 708 Google Scholar
Short, C. I. & Doyle, J. G. 1998, Astronomy & Astrophysics, 336, 613 Google Scholar
Spanó, P., Leone, F., Bruno, P., Catalano, S., Martinetti, E., Scuderi, S. 2006, MSAIS, 9, 481S Google Scholar
Spanó, P., Leone, F., Scuderi, S., Catalano, S., & Zerbi, F. M., 2004, SPIE, 5492, 373S Google Scholar
Uitenbroek, H. 1992, ASPC, 26, 546 Google Scholar
Vernazza, J. E., Avrett, E. H., & Loeser, R. 1973, Astrophysical Journal, 184, 605V Google Scholar
Vernazza, J. E., Avrett, E. H., & Loeser, R. 1981, Astrophysical Journal Supplement, 45, 635 CrossRefGoogle Scholar