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Cm Telescope (cm + telescope)
Selected AbstractsLOLAS: an optical turbulence profiler in the atmospheric boundary layer with extreme altitude resolutionMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2008R. Avila ABSTRACT We report the development and first results of an instrument called Low Layer SCIDAR (Scintillation Detection and Ranging) (LOLAS) which is aimed at the measurement of optical-turbulence profiles in the atmospheric boundary layer with high altitude resolution. The method is based on the Generalized SCIDAR (GS) concept, but unlike the GS instruments which need a 1-m or larger telescope, LOLAS is implemented on a dedicated 40-cm telescope, making it an independent instrument. The system is designed for widely separated double-star targets, which enables the high altitude resolution. Using a 200-arcsec-separation double star, we have obtained turbulence profiles with unprecedented 12-m resolution. The system incorporates necessary novel algorithms for autoguiding, autofocus and image stabilization. The results presented here were obtained at Mauna Kea Observatory. They show LOLAS capabilities but cannot be considered as representative of the site. A forthcoming paper will be devoted to the site characterization. The instrument was built as part of the Ground Layer Turbulence Monitoring Campaign on Mauna Kea for Gemini Observatory. [source] Sixty four nights of UBV photometry of early-type stars at La Sila,ASTRONOMISCHE NACHRICHTEN, Issue 3 2010P. Mayer Abstract UBV measurements of early-type stars, mostly eclipsing binaries, obtained at La Silla in the years 1990 to 1994 with the ESO 50 cm telescope are presented. Most of these data were already used in our individual studies of several binaries. Now all photometric measurements were reduced again with an advanced technique and are made available electronically. Our data for MY Ser have not yet been published; new light curve is given and solved. The result is that MY Ser is a contact binary, with very large fill-out parameter. Also a light curve and its solution for V1051 Cen are provided, and the problem of the period of V871 Cen is pointed out. Besides binaries (and the comparison and check stars) data for several stars in southern H II regions are included. Extinction and transformation coefficients are given (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Planetary transit observations at the University Observatory Jena: XO-1b and TrES-1,ASTRONOMISCHE NACHRICHTEN, Issue 5 2009St. Raetz Abstract We report on observations of transit events of the transiting planets XO-1b and TrES-1 with a 25 cm telescope of the University Observatory Jena. With the transit timings for XO-1b from all 50 available XO, SuperWASP, Transit Light Curve (TLC)-Project- and Exoplanet Transit Database (ETD)-data, including our own I -band photometry obtained in March 2007, we find that the orbital period is P = (3.941501 ± 0.000001) d, a slight change by ,3 s compared to the previously published period. We present new ephemeris for this transiting planet. Furthermore, we present new R -band photometry of two transits of TrES-1. With the help of all available transit times from literature this allows us to refine the estimate of the orbital period: P = (3.0300722 ± 0.0000002) d. Our observations will be useful for future investigations of timing variations caused by additional perturbing planets and/or stellar spots and/or moons (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Photometric monitoring of the young star Par 1724 in Orion,ASTRONOMISCHE NACHRICHTEN, Issue 5 2009R. Neuhäuser Abstract We report new photometric observations of the ,200 000 year old naked weak-line run-away T Tauri star Par 1724, located north of the Trapezium cluster in Orion. We observed in the broad band filters B, V, R, and I using the 90 cm Dutch telescope on La Silla, the 80 cm Wendelstein telescope, and a 25 cm telescope of the University Observatory Jena in Großschwabhausen near Jena. The photometric data in V and R are consistent with a ,5.7 day rotation period due to spots, as observed before between 1960ies and 2000. Also, for the first time, we present evidence for a long-term 9 or 17.5 year cycle in photometric data (V band) of such a young star, a cycle similar to that to of the Sun and other active stars (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||