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Related papers: Cyclical period changes in Z Chamaeleontis

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Short time scale photometric properties of eight faint Cataclysmic Variable (CV) stars are presented. Nova Carinae 1895 (RS Car) has a photometric modulation at 1.977 h which could be either an orbital or a superhump period. Nova Carinae…

Astrophysics · Physics 2009-11-07 Patrick A. Woudt , Brian Warner

The High Mass X-ray Binary (HMXB) SMC X-1 demonstrates an orbital variation of 3.89 days and a super-orbital variation with an average length of 55 days. As we show here, however, the length of the super-orbital cycle varies by almost a…

Astrophysics · Physics 2009-11-13 Sarah Trowbridge , Michael A. Nowak , Joern Wilms

The daily sunspot numbers of the whole disk as well as the northern and southern hemispheres from January 1, 1945 to December 31, 2010 are used to investigate the temporal variation of the rotational cycle length through the continuous…

Solar and Stellar Astrophysics · Physics 2015-06-03 J. -L. Xie , X. -J. Shi , J. -C. Xu

NSVS 14256825 is the second sdOB + dM eclipsing binary systems with an orbital period of 2.65 hours. The special binary was reported to contain circumbinary planets or brown dwarfs by using the timing method. However, different results were…

Solar and Stellar Astrophysics · Physics 2020-04-01 Zhu L. -Y. , Qian S. -B. , Fernandez Lajus , E. , Wang Z. -H. , Li L. -J

We present the results of an intensive multiwavelength campaign on nova LMC 2012. This nova evolved very rapidly in all observed wavelengths. The time to fall two magnitudes in the V band was only 2 days. In X-rays the super soft phase…

We report K2 observations of the eclipsing cataclysmic variable V729 Sgr which covered nearly 80 days in duration. We find five short outbursts and two long outbursts, one of which shows a clear plateau phase in the rise to maximum…

Solar and Stellar Astrophysics · Physics 2017-05-31 Gavin Ramsay , Matt A. Wood , John Cannizzo , Steve Howell , Alan Smale

We present optical photometry and spectroscopy of the new eclipsing Cataclysmic Variable MASTER OTJ192328.22+612413.5, discovered by the MASTER team. We find the orbital period to be P=0.16764612(5) day /4.023507(1) hour. The depth of the…

Solar and Stellar Astrophysics · Physics 2016-07-13 M. R. Kennedy , P. Callanan , P. M. Garnavich , P. Szkody , S. Bounane , B. M. Rose , P. Bendjoya , L. Abe , J. P. Rivet , O. Suarez

The period changes of contact binaries obtained by the analysis of eclipse minima timing are found mostly chaotic in nature. However, they are representable by a few cyclic changes superposed on a secular change. The cyclic changes are…

Solar and Stellar Astrophysics · Physics 2014-12-03 O. Demircan , İ Bulut

Twenty-one new optical light curves, including five curves obtained in 2009 and sixteen curves detected from the AAVSO International Database spanning from 1977 to 2011, demonstrate 16 new primary minimum light times in the high state.…

Solar and Stellar Astrophysics · Physics 2013-08-29 Zhibin Dai , Shengbang Qian , Linjia Li

We present high speed photometric observations of 20 faint cataclysmic variables, selected from the Sloan Digital Sky Survey and Catalina catalogues. Measurements are given of 15 new directly measured orbital periods, including four…

Solar and Stellar Astrophysics · Physics 2015-06-03 Patrick A. Woudt , Brian Warner , Deanne de Bude , Sally Macfarlane , Matthew P. E. Schurch , Ewald Zietsman

Years to decade-long cyclic period changes have been observed in many classes of close binaries. A common explanation invoked for these cyclic period changes is the gravitational influence of an unseen third body upon the close binary pair.…

Astrophysics · Physics 2007-05-23 R. T. Zavala

The evolution of novae and Cataclysmic Variables (CVs) is driven by changes in the binary orbital periods. In a direct and critical test for various evolution models and their physical mechanisms, I measure the sudden changes in the period…

Solar and Stellar Astrophysics · Physics 2023-08-02 Bradley E. Schaefer

We present measurements of the periods of Dwarf Nova Oscillations (DNOs) and Quasi-Periodic Oscillations (QPOs) in Cataclysmic Variable stars (CVs), many culled from published literature, but also others newly observed (in VZ Pyx, CR Boo,…

Astrophysics · Physics 2009-11-07 Brian Warner , Patrick A. Woudt , Magaretha L. Pretorius

In most Delta Scuti stars, the measured period changes are considerably larger than those expected from stellar evolution. In order to study these period and amplitude changes, a few selected stars are measured photometrically for hundreds…

Solar and Stellar Astrophysics · Physics 2015-05-14 Michel Breger

NSV 1907, formerly listed as an irregular variable in variability catalogues, was classified as an Algol-type eclipsing binary in the Catalina Surveys Periodic Variable Star Catalogue. We have identified NSV 1907 as an ultraviolet (UV)…

Planets in highly eccentric orbits form a class of objects not seen within our Solar System. The most extreme case known amongst these objects is the planet orbiting HD~20782, with an orbital period of 597~days and an eccentricity of 0.96.…

We present time-resolved V-photometry of the old nova RR Pic. Apart from the hump-like variability, the light curves show the strong flickering and random variation typical for RR Pic. We do not find any convincing evidence for the…

Astrophysics · Physics 2009-11-13 L. Schmidtobreick , C. Papadaki , C. Tappert , A. Ederoclite

We report extensive photometry of the dwarf nova QW Ser throughout its 2003 February superoutburst till quiescence. During the superoutburst the star displayed clear superhumps with a mean period of Psh = 0.07703(4) days. In the quiescence…

Astrophysics · Physics 2009-11-10 A. Olech , P. Kedzierski , K. Zloczewski , K. Mularczyk , M. Wisniewski

Abstract We investigate a short-period W UMa binary KIC 9026766 with an orbital period of 0.2721278 days in the Kepler field of view. By using an automated q-search for the folded light curve and producing a synthetic light curve for this…

Solar and Stellar Astrophysics · Physics 2022-01-05 Somaye Soomandar , Abbas Abedi

We applied the method of continuous wavelet-transform to high-quality time-frequency analysis to the sets of observations of relative sunspot numbers. Wavelet analysis of these data reveals the following pattern: at the same time there are…

Solar and Stellar Astrophysics · Physics 2015-12-15 A. A. Borisov , E. A. Bruevich , V. V. Bruevich , I. K. Rozgacheva , E. V. Shimanovskaya