发表机构
University of Washington; Institute of Applied Astronomy of Russian Academy of Sciences; Department of Astronomy, University of Illinois Urbana-Champaign; Rubin Observatory/NSF NOIRLab（华盛顿大学; 俄罗斯科学院应用天体物理研究所; 伊利诺伊大学厄巴纳-香槟分校天文学系; 鲁宾天文台/美国国家光学红外天文实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
提出一种为每个天体单独选择傅里叶阶数的改进自转周期确定方法，应用于Rubin DP2星表，发现66颗超快自转小行星，其中两颗直径超2公里、自转周期约5分钟，最大者491384直径约2.5公里。
AI 中文摘要
大型巡天的时间分辨测光可以确定大量小行星的自转周期，但前提是每个周期的可靠性需被自动评估，因为稀疏且不规则的采样会产生许多虚假的周期图极小值。我们提出了一种改进方法，通过为每个天体单独选择傅里叶级数的阶数来确定小行星的自转周期。与低阶方法相比，该方法具有显著优势，尤其是在无法可靠确定自转周期的唯一解时。在这种情况下，该方法会报告一组备选周期及其相应的概率估计。我们将改进的自转周期确定方法应用于NSF-DOE Vera C. Rubin天文台数据预览2（DP2）太阳系天体星表，并为大量小行星样本确定了可靠的周期。其中，我们发现了66颗超快自转体，它们的自转速度快于经典的2.2小时自转屏障。其中两颗尤为引人注目：小行星491384和566130的直径均大于2公里，但它们在约五分钟内完成一次完整自转。要在如此快的自转下幸存，它们必须具有显著的内聚力。小行星491384的直径约为2.5公里，是迄今已知最大的超快自转体。
英文摘要
Time-resolved photometry from large surveys can yield rotation periods for huge numbers of asteroids, but only if the reliability of each period is assessed automatically, since sparse and irregular sampling produces many false periodogram minima. We present an improved method that determines asteroid rotation periods with a Fourier series whose order is chosen for each object individually. This has substantial advantages over lower order methods, especially when unique solutions for the spin period cannot be reliably determined. In such cases, the method reports the set of alternative periods together with the corresponding probability estimates. We apply the improved spin period determination method to the NSF-DOE Vera C. Rubin Observatory Data Preview 2 (DP2) catalog of solar system objects and determine reliable periods for a large sample of asteroids. Among them we find 66 super-fast rotators, which spin faster than the classical 2.2 h spin barrier. Two of them are remarkable: asteroids 491384 and 566130 are both larger than 2 km, yet they complete a full rotation in only about five minutes. To survive such a fast spin, they must have significant internal cohesion. At a diameter of about 2.5 km, asteroid 491384 is the largest ultra-fast rotator known so far.
Comments27 pages, 8 figures, 4 tables
