Asteroseismology can reveal strong internal magnetic fields in red giant stars

作者：Fuller Jim^*; Cantiello Matteo; Stello Dennis; Garcia Rafael A; Bildsten Lars

来源：Science, 2015, 350(6259): 423-426.

DOI：10.1126/science.aac6933

Internal stellar magnetic fields are inaccessible to direct observations, and little is known about their amplitude, geometry, and evolution. We demonstrate that strong magnetic fields in the cores of red giant stars can be identified with asteroseismology. The fields can manifest themselves via depressed dipole stellar oscillation modes, arising from a magnetic greenhouse effect that scatters and traps oscillation-mode energy within the core of the star. The Kepler satellite has observed a few dozen red giants with depressed dipole modes, which we interpret as stars with strongly magnetized cores. We find that field strengths larger than similar to 10(5) gauss may produce the observed depression, and in one case we infer a minimum core field strength of approximate to 10(7) gauss.

• 出版日期2015-10-23
• 单位中国科学院理论物理研究所