Articles

 

Physical parameters of three field RR Lyrae stars¹

 

A. Arellano Ferro,² J. H. Peña,² and R. Figuera Jaimes^3,4

 

² Instituto de Astronomía, Universidad Nacional Autónoma de México, Apdo. Postal 70–264, México, D.F., 04510, México. (armando@astro.unam.mx, jhpena@astro.unam.mx).

³ European Southern Observatory, Karl–Schwarzschild–Str. 2, 85748 Garching bei München, Germany. (rfiguera@eso.org, robertofiguera@gmail.com).

⁴ SUPA, School of Physics and Astronomy, University of St. Andrews, UK.

 

Received 2012 September 20.
Accepted 2012 November 1.

 

RESUMEN

La fotometría Strömgren uvby — β de las estrellas clasificadas como RR Lyrae RU Piscium, SS Piscium and TU Ursae Majoris, ha sido empleada para estimar la abundancia de hierro, la temperatura efectiva, la gravedad superficial y la magnitud absoluta. Se discute la variabilidad secular del período de pulsación. El enrojecimiento de cada estrella se ha estimado a partir de los colores de Stromgren y de mapas celestes de enrojecimiento. Se reportan y comparan los resultados para [Fe/H], T_eff y log(g) obtenidos por alguno de los siguientes metodos: Descomposición de Fourier de la curva de luz, el índice ΔS de Preston y la comparación con las mallas teóricas en el plano (b — y)_o — c_1o.

 

ABSTRACT

Strömgren uvby — β photometry of the stars classified as RR Lyrae stars RU Piscium, SS Piscium and TU Ursae Majoris has been used to estimate their iron abundance, temperature, gravity and absolute magnitude. The stability of the pulsating period is discussed. The nature of SS Psc as a RRc or a HADS is addressed. The reddening of each star is estimated from the Strömgren colour indices and reddening sky maps. The results of three approaches to the determination of [Fe/H], T_eff and log(g) are discussed: Fourier light curve decomposition, the Preston ΔS index and the theoretical grids on the (b — y)_o — c_1o plane.

Key Words: stars: variables: RR Lyrae — techniques: photometry.

 

DESCARGAR ARTÍCULO EN FORMATO PDF

 

ACKNOWLEDGMENTS

We are grateful to Joan Miller for proof reading the manuscript. This work was partially supported by DGAPA–Universidad Nacional Autonoma de Mexico through project IN104612. The authors have made extensive use of the SIMBAD database operated at CDS, Strasbourg, France and the NASA Astrophysics Data Systems hosted by the Harvard–Smithsonian Center for Astrophysics.

 

REFERENCES

Agerer, F., & Hübscher, J. 1996, Inf. Bull. Variable Stars, 4382, 1        [ Links ]

Alard C. 2000, A & AS, 144, 363        [ Links ]

Alcock, C., et al. 2000, ApJ, 542, 257        [ Links ]

Antonello, E., Broglia, P., Conconi, P., & Mantegazza, L. 1986, A & A, 169, 122         [ Links ]

Arellano Ferro, A., Arévalo, M. J., Lázaro, C., Rey, M., Bramich, D. M., & Giridhar, S. 2004, RevMexAA, 40, 209        [ Links ]

Arellano Ferro, A., Bramich, D. M., Figuera Jaimes, R., Giridhar, S., & Kuppuswamy, K. 2012, MNRAS, 420, 1333        [ Links ]

Arellano Ferro, A., Figuera Jaimes, R., Giridhar, S., Bramich, D. M., Hernández Santisteban, J. V., & Kuppuswamy, K. 2011, MNRAS, 416, 2265         [ Links ]

Arellano Ferro, A., Giridhar S., & Bramich, D. M. 2010, MNRAS, 402, 226         [ Links ]

Arellano Ferro, A., Rojas López, V., Giridhar, S., & Bramich, D. M. 2008, MNRAS, 384, 1444        [ Links ]

Blažko, S. 1907, Astron. Nachr., 175, 325         [ Links ]

Bookmeyer, B. B., Fitch, W. S., Lee, T. A., Wisniewski, W. Z., & Johnson, H. L. 1977, RevMexAA, 2, 235        [ Links ]

Bramich D. M. 2008, MNRAS, 386, L77        [ Links ]

Bramich D. M., Figuera Jaimes, R., Giridhar, S., & Arellano Ferro, A. 2011, MNRAS, 413, 1275        [ Links ]

Cacciari, C., & Clementini, G. 2003, in Stellar Candles for Extragalactic Distance Scale, ed. D. Alloin & W. Gieren (Berlin: Springer), 105        [ Links ]

Cacciari, C., Corwin, T. M., & Carney, B. W. 2005, ApJ, 129, 267        [ Links ]

Chaboyer, B. 1999, in Post–Hipparcos Cosmic Candles, ed. A. Heck & F. Caputo (Dordrech: Kluwer), 111        [ Links ]

Clementini, G., Gratton, R., Bragaglia, A., Carretta, E., Di Fabrizio, L., & Maio, M. 2003, AJ, 125, 1309         [ Links ]

Crawford, D. L. 1975, AJ, 80, 955        [ Links ]

Derekas, A., Kiss, L. L., Udalski, A., Bedding, T. R., & Szatmáry, K. 2004, MNRAS, 354, 821         [ Links ]

Fernley, J., & Barnes, T. G. 1997, A & AS, 125, 313        [ Links ]

Fernley, J., Barnes, T. G., Skillen, I., Hawley, S. L., Hanley, C. J., Evans, D. W., Solano, E., & Garrido, R. 1998, A & A, 330, 515         [ Links ]

Guggenberger, E., et al. 2012, MNRAS, 424, 649         [ Links ]

Hauck, B., & Mermilliod, M. 1998, A & AS, 129, 43         [ Links ]

Jurcsik, J. 1995, Acta Astron., 45, 653        [ Links ]

––––––––––. 1998, A & A, 333, 571        [ Links ]

Jurcsik, J., & Kovács, G. 1996, A & A, 312, 111         [ Links ]

Kains, N., Bramich, D. M., Figuera Jaimes, R., Arellano Ferro, A., Giridhar, S., & Kuppuswamy, K. 2012, A & A, 548, A92        [ Links ]

Kholopov, P. N., et al. 1987, General Catalogue of Variable stars (Moscow: Nauka)         [ Links ]

Kiss, L., Szatmary, K., Gal, J., & Kaszas, G. 1995, Inf. Bull. Variable Stars, 4205, 1         [ Links ]

Kovács, G. 1998, Mem. Soc. Astron. Italiana, 69, 49         [ Links ]

Kovács, G., & Walker, A. R. 2001, A & A, 371, 579         [ Links ]

Layden, A. C. 1994, AJ, 108, 1016        [ Links ]

Lázaro, C., Arellano Ferro, A., Arévalo, M. J., Bramich, D. M., Giridhar, S., & Poretti, E. 2006, MNRAS, 372, 69        [ Links ]

Lenz, P., & Breger, M. 2004, IAU Symp. 224, The A–Star Puzzle, ed. J. Zverko, J. Ziznovsky, S. J. Adelman, & W. W. Weiss (Cambridge: Cambridge Univ. Press), 786        [ Links ]

Lester, J. B., Gray, R. O., & Kurucz, R. I. 1986, ApJ, 61, 509        [ Links ]

McNamara, D. H., & Redcorn, M. E. 1977, PASP, 89, 61         [ Links ]

Mendes de Oliveira, C., & Nemec, J. M. 1988, PASP, 100, 217        [ Links ]

Moskalik, P., & Olech, A. 2008, Commun. Asteroseismol., 157, 345        [ Links ]

Moskalik, P., & Poretti, E. 2003, A & A, 398, 213        [ Links ]

Moskalik, P., et al. 2012, arXiv:1208.4251        [ Links ]

Morgan, S., Wahl, J. N., & Wieckhorts, R. M. 2007, MNRAS, 374, 1421        [ Links ]

Olech, A., Kaluzny, J., Thompson, I. B., Pych, W., Krzemináski, W., & Shwarzenberg–Czerny, A. 1999, AJ, 118, 442        [ Links ]

––––––––––. 2001, MNRAS, 321, 421        [ Links ]

Oosterhoff, P. T. 1939, Observatory, 62, 104        [ Links ]

Peña, J. H., Arellano Ferro, A., Peña Miller, R., Sareyan, J. P., & Álvarez, M. 2009, RevMexAA, 45, 191        [ Links ]

Peña, J. H., Figuera Jaimes, R., Chow, M., Peña Miller, R., & Álvarez, M. 2012, RevMexAA, 48, 299         [ Links ]

Preston, G. W. 1959, ApJ, 130, 507         [ Links ]

Rodríguez, E., et al. 1994, A & AS, 106, 21        [ Links ]

Saha, A., & White, R. E. 1990, PASP, 102, 148         [ Links ]

Schlegel, D. J., Finkbeiner, D. P., & Davis, M. 1998, ApJ, 500, 525        [ Links ]

Schuster, W. J., & Nissen, P. E. 1988, A & AS, 73, 225         [ Links ]

Simon, N. R., & Clement, C. M. 1993, ApJ, 410, 526         [ Links ]

Soszyński, I., et. al. 2009, Acta Astron., 59, 1         [ Links ]

Suntzeff, N. B., Kraft, R. P., & Kinman, T. D. 1994, ApJS, 93, 271        [ Links ]

Szeidl, B., Olah, K., & Mizzer, A. 1986, Commun. Konkoly Obs., 89, 57        [ Links ]

Tremko, J. 1964, Commun. Konkoly Obs., 55, 1        [ Links ]

Wade, R. A., Donley, J., Fried, R., White, R. E., & Saha, A. 1999, AJ, 118, 2442        [ Links ]

Zinn, R., & West, M. J. 1984, ApJS, 55, 45        [ Links ]

 

NOTE

Based on observations collected at the San Pedro Mártir Observatory, Mexico.