AAVSO: American Association of Variable Star Observers

AL Pictoris and FR Piscium: Two Regular Blazhko RR Lyrae Stars

Volume 42 number 2 (2014)

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Pierre de Ponthière
15 Rue Pré Mathy, Lesve, Profondeville 5170, Belgium; address email correspondence to pierredeponthiere@gmail.com
Franz-Josef Hambsch
12 Oude Bleken, Mol, 2400, Belgium
Kenneth Menzies
318A Potter Road, Framingham, MA 01701
Richard Sabo
2336 Trailcrest Drive, Bozeman, MT 59718


The results presented are a continuation of observing campaigns conducted by a small group of amateur astronomers interested in the Blazhko effect of RR Lyrae stars. The goal of these observations is to confirm the RR Lyrae Blazhko effect and to detect any additional Blazhko modulation which cannot be identified from all sky survey data-mining. The Blazhko effect of the two observed stars is confirmed, but no additional Blazhko modulations have been detected. The observation of the RR Lyrae star AL Pictoris during 169 nights was conducted from San Pedro de Atacama (Chile). From the observed light curve, 49 pulsation maxima have been measured. Fourier analyses of (O-C), magnitude at maximum light (Mmax), and the complete light curve have provided a confirmation of published pulsation and Blazhko periods, 0.548622 and 34.07 days, respectively. The second multi-longitude observation campaign focused on the RR Lyrae star FR Piscium and was performed from Europe, the United States, and Chile. Fourier analyses of the light curve and of 59 measured brightness maxima have improved the accuracy of pulsation and Blazhko periods to 0.45568 and 51.31 days, respectively. For both stars, no additional Blazhko modulations have been detected.