We analyze the long-term activity of a little known dwarf nova (DN) DT Oct. We use photographic observations from the Bamberg Observatory (Southern Patrol Photographic Sky Survey), CCD data from ASAS-3 survey, and AAVSO data (both CCD and visual). We determined the recurrence times of the superoutbursts, T_Cso, and of the normal outbursts, T_Cno, to be approximately 311 d and about 30 d, respectively. Although the length of T_Cso evolves gradually and undergoes only small variations (increases and decreases) of the nearby or neighbouring events (on the timescale of a few epochs), the evolution of T_Cso displays considerably larger changes on the longer timescales. They suggest a dominant trend of a decrease of T_Cso on the timescale of tens of years. The possibly magnetized white dwarf does not prevent DT Oct to show the long-term activity of the SU UMa systems. We place the time evolution of the superoutbursts of DT Oct in the context of DNe of various sub-types.

中文翻译：

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鲜为人知的矮矮新星DT Octantis的长期活动

我们分析了一个鲜为人知的矮新星（DN）DT十月的长期活动。我们使用了班贝格天文台（南部巡逻照相天空调查）的摄影观测结果，ASAS-3调查的CCD数据以及AAVSO数据（CCD和视觉）。我们确定超爆发的复发时间T _Cso和正常爆发的复发时间T _Cno分别约为311 d和约30 d。尽管T _Cso的长度是逐渐变化的，并且仅发生附近或邻近事件的微小变化（增加和减少）（在几个纪元的时间尺度上），但T _Cso的演变在更长的时间范围内显示相当大的变化。他们提出了在几十年的时间尺度上T _Cso降低的主要趋势。可能被磁化的白矮星不会阻止DT Oct显示SU UMa系统的长期活动。我们将DT Oct超爆发的时间演化置于各种子类型的DNe中。