Reduction of Benzils Promoted by a New Class of Bifunctional Organocatalysts

We report on the time-resolved optical CCD photometry of newly discovered SU UMa-type dwarf novae, FL TrA and CTCVJ0549$-$4921. During a 2006 August outburst, we detected superhumps with a period of 0.59897(11) days for FL TrA, clarifying the SU UMa nature of the system. On the first night of our observations of FL TrA, the object showed no superhumps. This implies that it takes a few days for the full development of superhumps. The superhump period variation diagram of FL TrA was similar to that observed in some WZ Sge stars and short-period SU UMa-type stars. This indicates that the system is closely related to WZ Sge stars and SU UMa stars having short orbital periods. For CTCV J0549$-$4921, the candidates of the mean superhump period are 0.083249(10) days and 0.084257(8) days, respectively. Due to a lack of observations, we cannot determine the true superhump period, but the latter period is favorable. Using the ASAS-3 archive, it turned out that the system showed only four outbursts over the past 6 years. The outburst amplitude of CTCV J0549$-$4921 was relatively small, with about 4.5 mag. One possibility is that mass evaporation may play a role during quiescence.

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The 2006 November Outburst of EG Aquarii: the SU UMa Nature Revealed

Imada

Stubbings

Katô

et al. 2008

Publications of the Astronomical Society of Japan

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We report on time-resolved CCD photometry of the cataclysmic variable EG Aquarii during a 2006 November outburst. During the outburst, superhumps were unambiguously detected with a mean period of 0.078828(6) d, allowing for the first time to classify the object as an SU UMa-type dwarf nova. It also turned out that the outburst contained a precursor. At the end of the precursor, immature profiles of humps were observed. By a phase analysis of these humps, we interpreted the features as being superhumps. This is the second example that the superhumps were shown during a precursor. Near the maximum stage of the outburst, we discovered an abrupt shift of the superhump period by ${\sim\;}$0.002 d. After the supermaximum, the superhump period decreased at a rate of $\dot{P}/P =$$-$8.2${\;\times\;}$10$^{-5}$, which is typical for SU UMa-type dwarf novae. Although the outburst light curve was characteristic of SU UMa-type dwarf novae, long-term monitoring of the variable shows no outbursts over the past decade. We also comment on the basic properties of long period and inactive SU UMa-type dwarf novae.

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Reduction of Benzils Promoted by a New Class of Bifunctional Organocatalysts

Cited by 6 publications

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Introduction to Cataclysmic Variable Stars

Introduction to Cataclysmic Variable Stars

Photometric Studies of New Southern SU UMa-Type Dwarf Novae, FL Trianguli Australis and CTCV J0549–4921

The 2006 November Outburst of EG Aquarii: the SU UMa Nature Revealed

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