The ? Dor variable HR 8799: Results from a multisite campaign
Por:
Zerbi F.M., Rodríguez E., Garrido R., Martín S., Arellano Ferro A., Sareyan J.P., Krisciunas K., Akan M.C., Evren S., Ibanoglu C., Keskin V., Pekünlü R., Tunca Z., Luedeke K., Paparó M., Nuspl J., Guerrero G.
Publicada:
1 ene 1999
Resumen:
In this paper, we present the results of a multisite photometric campaign devoted to the ? Doradus type variable HR 8799. From Johnson and Strömgren data, we were able to identify three independent frequencies (f1, = 1.9791 cycle d-1,f2 = 1.7268 cycle d-1 and f3 = 1.6498 cycle d-1) as well as another signal, which we are able to identify as the coupling term between two of the frequencies (f4 = f1 - f2 = 0.2479 cycle d-1). These four frequencies are able to account for all of the observed variations down to the 1? significance level. We discuss another possible interpretation of these frequencies using a model of quasi-stochastic amplitude modulation. In this scenario, we are able to show that HR 8799 might be pulsating with two independent frequencies, one of which undergoes amplitude modulation similar to other ? Dor objects. In addition, we discuss a preliminary mode identification based on the observed colour curves. Finally, 18 simultaneous, high-resolution echelle spectra were collected on two nights and we qualitatively compare the radial velocities from these data with our photometry.
Filiaciones:
Osservatorio Astronomico di Brera, Via Bianchi 46, I-23807 Merate, Italy
Inst. de Astrofis. de Andalucia, CSIC, Apdo 3004, E-18080 Granada, Spain
Departamento de Astronomía, IFUG, Universidad de Guanajuato, Apdo Postal 144, Guanajuato, Gto 36000, Mexico
Observatoire de la Côte d'Azur, BP 4229, 0634 Nice Cedex 4, France
Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195-1580, United States
Ege University Observatory, Bornova, Izmir, Turkey
9624 Giddings Avenue NE, Albuquerque, NM 87109, United States
Konkoly Observatory, PO Box 67, 1525 Budapest XII, Hungary
All Open Access; Bronze
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