Recently, a class of long-period radio transients (LPTs) has been discovered, exhibiting emission thousands of times longer than radio pulsars^1,2,3,4,5. These findings, enabled by advances in wide-field radio surveys, challenge existing models of rotationally powered pulsars. Proposed models include highly magnetized neutron stars⁶, white-dwarf pulsars⁷ and white-dwarf binary systems with low-mass companions⁸. Although some models predict X-ray emission^6,9, no LPTs have been detected in X-rays despite extensive searches^1,2,3,4,5,10. Here we report the discovery of an extremely bright LPT (10–20 Jy in radio), ASKAP J1832−0911, which has coincident radio and X-ray emission, both with a 44.2-minute period. Its correlated and highly variable X-ray and radio luminosities, combined with other observational properties, are unlike any known Galactic object. The source could be an old magnetar or an ultra-magnetized white dwarf; however, both interpretations present theoretical challenges. This X-ray detection from an LPT reveals that these objects are more energetic than previously thought and establishes a class of hour-scale periodic X-ray transients with a luminosity of about 10³³ erg s⁻¹ linked to exceptionally bright coherent radio emission.

最近，发现了一类长周期射电瞬变 （LPT），其发射时间比射电脉冲星 ^1,2,3,4,5 长数千倍。这些发现得益于宽视场射电巡天的进展，挑战了现有的旋转动力脉冲星模型。提出的模型包括高度磁化的中子星 ⁶ （high magnetized neutron stars）、白矮星脉冲星 7 （white-dwarf pulsars⁷） 和具有低质量伴星的白矮星双星系统 ⁸ （white-dwarf binary system）。尽管一些模型预测 X 射线发射 ^6,9，但尽管进行了广泛的搜索，但仍未在 X 射线中检测到 LPT^1,2,3,4,5,10。在这里，我们报告了一种非常亮的 LPT（无线电中为 10-20 Jy）的发现，ASKAP J1832-0911，它具有重合的无线电和 X 射线发射，周期均为 44.2 分钟。它相关且高度可变的 X 射线和射电光度，再加上其他观测特性，与任何已知的银河系天体都不同。源可能是旧磁星或超磁化白矮星;然而，这两种解释都提出了理论上的挑战。来自 LPT 的 X 射线探测表明，这些天体的能量比以前认为的要高，并建立了一类小时尺度的周期性 X 射线瞬变，其光度约为 10³³ erg s⁻¹，与异常明亮的相干射电发射有关。