Browsing by Author "Handler, G"

Now showing 1 - 4 of 4
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    2MASS J0516288+260738: Discovery of the first eclipsing late K + Brown dwarf binary system?
    (2003) Schuh, S L; Handler, G; Drechsel, H; Hauschildt, P; Dreizler, S; Medupe, R; Karl, C; Napiwotzki, R; Kim, S-L; Park, B-G; Wood, M A; Paparó, M; Szeidl, B; Virághalmy, G; Zsuffa, D; Hashimoto, O; Kinugasa, K; Taguchi, H; Kambe, E; Leibowitz, E; Ibbetson, P; Lipkin, Y; Nagel, T; Göhler, E; Pretorius, M L
    We report the discovery of a new eclipsing system less than one arcminute south of the pulsating DB white dwarf
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    On the Period-Luminosity-Colour-Metallicity relation and the pulsational characteristics of λ  Bootis type stars
    (2002) Paunzen, E; Handler, G; Weiss, W W; Nesvacil, N; Hempel, A; Romero-Colmenero, E; Vuthela, F F; Reegen, P; Shobbrook, R R; Kilkenny, D
    Generally, chemical peculiarity found for stars on the upper main sequence excludes
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    Preparing the COROT space mission: Incidence and characterisation ofpulsation in the lower instability strip
    (2003) Poretti, E; Garrido, R; Amado, P J; Uytterhoeven, K; Handler, G; Alonso, R; Martin, S; Aerts, C; Catala, C; Goupil, M J; Michel, E; Mantegazza, L; Mathias, P; Pretorius, M L; Belmonte, J A; Claret, A; Rodríguez, E; Suarez, J C; Vuthela, F F; Weiss, W W; Ballereau, D; Bouret, J C; Charpinet, S; Hua, T; LYftinger, T; Nesvacil, N; Van\'t Veer-Menneret, C
    By pursuing the goal to find new variables in the COROT field-of-view we characterised a sample of stars located in the lower part of the instability strip. Our sample is composed of stars belonging to the disk population in the solar neighbourhood. We found that 23% of the stars display multiperiodic light variability up to a few mmag in amplitude, i.e., easily detectable on a single night of photometry.
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    The δ Scuti star FG Vir.V. The 2002 photometric multisite campaign
    (2004) Breger, M; Rodler, F; Pretorius, M L; Martín-Ruiz, S; Amado, P J; Costa, V; Garrido, R; Olivares, I; Rodríguez, E; Rolland, A; Tshenye, T; Handler, G; Poretti, E; Sareyan, J P; Alvarez, M; Kilmartin, P M; Zima, W
    A high-accuracy multisite campaign was carried out from 2002 January to May with a photometric coverage of 398 h at five observatories. The concentration on a few selected sites gives better consistency and accuracy than collecting smaller amounts from a larger number of sites. 23 frequencies were detected with a high statistical significance. 6 of these are new. The 17 frequencies found in common with the 1992-1995 data are the modes with highest amplitudes. This indicates that the pulsation spectrum of FG Vir is relatively stable over the ten-year period. Two frequencies have variable amplitudes and phases from year to year as well as during 2002. These were both found to be double modes with close frequencies. For the mode at 12.15 c/d this leads to an apparent modulation with a time scale of ~129 d. The close frequencies at 12.15 c/d are composed of a radial and a nonradial mode, suggesting a similarity with the Blazhko Effect seen in RR Lyrae stars.