000002000 001__ 2000
000002000 005__ 20160701171657.0
000002000 0247_ $$2DOI$$a10.1051/0004-6361:20077514
000002000 037__ $$aASTROimport-157
000002000 100__ $$aRodríguez, E.
000002000 245__ $$aThe field high-amplitude SX Phoenicis variable BL Camelopardalis: results from a multisite photometric campaign. I. Pulsation
000002000 260__ $$c2007
000002000 520__ $$aContext: BL Cam is an extreme metal-deficient field high-amplitude SX Phe-type variable where a very complex frequency spectrum is detected, with a number of independent nonradial modes excited, unusual among the high-amplitude pulsators in the Lower Classical Instability Strip. Aims: An extensive and detailed study has been carried out to investigate the pulsational content and properties of this object. Methods: The analysis is based on 283 h of CCD observations obtained in the Johnson V filter, during a long multisite photometric campaign carried out along the Northern autumn-winter of 2005-2006. Additionally, multicolour BI photometry was also collected to study the phase shifts and amplitude ratios, between light curves obtained in different filters, for modal discrimination of the main excited modes.  Results: The detailed frequency analysis revealed a very rich and dense pulsational content consisting of 25 significant peaks, 22 of them corresponding to independent modes: one is the already known main periodicity f0 = 25.5765 cd-1 (Δ V = 153 mmag) and the other 21 are excited modes showing very small amplitudes. Some additional periodicities are probably still remaining in the residuals. This represents the most complex spectrum ever detected in a high-amplitude pulsator of this type. The majority of the secondary modes suspected from earlier works are confirmed here and, additionally, a large number of new peaks are detected. The amplitude of the main periodicity f0 seems to be stable during decades, but the majority of the secondary modes show strong amplitude changes from one epoch to another. The suspected fundamental radial nature of the main periodicity of BL Cam is confirmed, while the secondary peak f1 = 25.2523 cd-1 is identified as a nonradial mixed mode g4 with ℓ = 1. The radial double-mode nature, claimed by some authors for the main two frequencies of BL Cam, is not confirmed. Nevertheless, the frequency f6 = 32.6464 cd-1 could correspond to the first radial overtone.
000002000 700__ $$a Fauvaud, S.
000002000 700__ $$a Farrell, J. A.
000002000 700__ $$a Zhou, A.-Y.
000002000 700__ $$a Sareyan, J.-P.
000002000 700__ $$a López-González, M. J.
000002000 700__ $$a Dupret, M.-A.
000002000 700__ $$a Grigahcéne, A.
000002000 700__ $$a De Ridder, J.
000002000 700__ $$a Klingenberg, G.
000002000 700__ $$a Wolf, M.
000002000 700__ $$a van Cauteren, P.
000002000 700__ $$a Lampens, P.
000002000 700__ $$a Martínez, D.
000002000 700__ $$a Casanova, V. M.
000002000 700__ $$a Aceituno, F. J.
000002000 700__ $$a Helvaci, M.
000002000 700__ $$a Hintz, E. G.
000002000 700__ $$a Král, L.
000002000 700__ $$a Fumagalli, F.
000002000 700__ $$a Simonetti, J. H.
000002000 700__ $$a Granslo, B. H.
000002000 700__ $$a Kotková, L.
000002000 700__ $$a Santacana, G.
000002000 700__ $$a Michelet, J.
000002000 700__ $$a Fauvaud, M.
000002000 700__ $$a Vugnon, J.-M.
000002000 700__ $$a Sadsaoud, H.
000002000 700__ $$a Aliouane, S.
000002000 700__ $$a Grigahcéne, Z. C.
000002000 700__ $$a Martín-Ruíz, S.
000002000 700__ $$a Amado, P. J.
000002000 700__ $$a Suárez, J. C.
000002000 700__ $$a Moya, A.
000002000 700__ $$a Kucáková, H.
000002000 700__ $$a Kocián, R.
000002000 700__ $$a Truparová, K.
000002000 700__ $$a Avdibegovic, A.
000002000 700__ $$a Blažek, M.
000002000 700__ $$a Kliner, J.
000002000 700__ $$a Zasche, P.
000002000 700__ $$a Vilásek, M.
000002000 700__ $$a Bartošíková, S.
000002000 700__ $$a Yasarsoy, B.
000002000 700__ $$a Ulusoy, C.
000002000 700__ $$a Graham, K. A.
000002000 700__ $$a Nicholson, M. P.
000002000 700__ $$a Trondal, O.
000002000 700__ $$a Yesilyaprak, C.
000002000 700__ $$a Coker, D.
000002000 773__ $$c255-264$$i1$$pAstronomy and Astrophysics$$v471$$y2007
000002000 85642 $$ahttp://esoads.eso.org/abs/2007A%26A...471..255R
000002000 905__ $$apublished in
000002000 980__ $$aREFERD