Site Map
Follow us on Facebook Follow us on Twitter YouTube channel
Centro de Astrofísica da Universidade do Porto

Delta Scuti stars in Praesepe I. The STACC 1998 campaign - The photometry

S. Frandsen, J. Nuspl, A. Pigulski, M. Breger, J. A. Belmonte, T. Dall, T. Arentoft, C. Sterken, T. Medupe, S. K. Gupta, F. J. G. Pinheiro, M. J. P. F. G. Monteiro, C. Barban, M. Chevreton, E. Michel, J. M. Benko, Sz. Barcza, R. Szabó, Z. Kołaczkowski, G. Kopacki, S. N. Udovichenko

We present the results of the multisite differential CCD photometry for the two delta Scuti stars, BN and BV Cnc, in the open cluster Praesepe. The main objective was to identify the character of the pulsation modes in BN Cnc deriving their accurate periods, amplitudes and phases. These parameters are essential for the mode identification which uses combined photometric and spectroscopic data and is presented in the second article. For BN Cnc, six pulsation modes with amplitudes above the detection limit ( ~ 0.5 mmag) were detected. Using the same CCD frames it was possible to verify the presence of the four pulsation modes in BV Cnc, the faintest of delta Scuti stars in Praesepe. It is shown that in this very low-amplitude pulsator, substantial amplitude variations are seen between 1997 and 1998. Based in part on observations obtained at the European Southern Observatory at La Silla, Chile (Application 60D-0148).

Astronomy and Astrophysics
Volume 376, Page 175
September 2001

>> PDF>> ADS>> DOI

Institute of Astrophysics and Space Sciences

Institute of Astrophysics and Space Sciences (IA) is a new but long anticipated research infrastructure with a national dimension. It embodies a bold but feasible vision for the development of Astronomy, Astrophysics and Space Sciences in Portugal, taking full advantage and fully realizing the potential created by the national membership of the European Space Agency (ESA) and the European Southern Observatory (ESO). IA resulted from the merging the two most prominent research units in the field in Portugal: the Centre for Astrophysics of the University of Porto (CAUP) and the Center for Astronomy and Astrophysics of the University of Lisbon (CAAUL). It currently hosts more than two-thirds of all active researchers working in Space Sciences in Portugal, and is responsible for an even greater fraction of the national productivity in international ISI journals in the area of Space Sciences. This is the scientific area with the highest relative impact factor (1.65 times above the international average) and the field with the highest average number of citations per article for Portugal.

Proceed on CAUP's website|Go to IA website