The dissipation of turbulence in astrophysical systems is fundamental to energy transfer and heating in environments ranging from the solar wind and corona to accretion disks and the intracluster medium. Although turbulent dissipation is relatively well understood in fluid dynamics, astrophysical plasmas often exhibit exotic behaviour, arising from the lack of interparticle collisions, which complicates turbulent dissipation and heating in these systems. Recent observations by NASA’s Parker Solar Probe mission in the inner heliosphere have shed new light on the role of ion cyclotron resonance as a potential candidate for turbulent dissipation and plasma heating. Here, using in situ observations of turbulence and wave populations, we show that ion cyclotron waves provide a major pathway for dissipation and plasma heating in the solar wind. Our results support recent theoretical predictions of turbulence in the inner heliosphere, known as the helicity barrier, that suggest a role of cyclotron resonance in ion-scale dissipation. Taken together, these results provide important constraints for turbulent dissipation and acceleration efficiency in astrophysical plasmas.

天体物理系统中湍流的耗散对于太阳风、日冕、吸积盘和星团内介质等环境中的能量传输和加热至关重要。尽管湍流耗散在流体动力学中相对较好地理解，但天体物理等离子体经常表现出奇异的行为，这是由于缺乏粒子间碰撞而引起的，这使这些系统中的湍流耗散和加热变得复杂。美国宇航局帕克太阳探测器任务最近在内日球层进行的观测，为离子回旋共振作为湍流耗散和等离子体加热的潜在候选者的作用提供了新的线索。在这里，通过对湍流和波群的现场观测，我们表明离子回旋波为太阳风中的耗散和等离子体加热提供了主要途径。我们的结果支持了最近对内部日光层湍流（称为螺旋势垒）的理论预测，该预测表明回旋加速器共振在离子尺度耗散中的作用。总而言之，这些结果为天体物理等离子体中的湍流耗散和加速效率提供了重要的约束。