HD80606在行星近星点附近的射电观测：II。LOFAR在30-78兆赫的低波段天线观测
Radio Observations of HD80606 Near Planetary Periastron: II. LOFAR Low Band Antenna Observations at 30-78 MHz
摘要：
太阳系中所有的巨行星都通过电子回旋脉泽不稳定性产生射电辐射，最显著的是木星的十米波辐射。所有这些太阳系电子回旋脉泽的产生，至少部分是由于与太阳风的相互作用。HD 80606 b是一颗巨大的行星，轨道高度偏心，因此预测其无线电辐射可能在近星点附近大幅增强。本文报道了HD 80606 b的低频阵列（LOFAR）在其近星点附近的观测结果，以探测行星磁层中电子回旋脉泽不稳定性产生的无线电发射。报告的观测频率在30兆赫和78兆赫之间，它们与以前大多数太阳系外行星的射电观测有两个区别：（i）它们的频率接近50兆赫，更接近木星发射的频率（< 40 MHz），并且低于大多数以前报告的太阳系外行星观测;和（ii）灵敏度约为几毫扬斯基，比以前在100兆赫以下观测到的几乎所有太阳系外行星低一个数量级或更多。我们没有探测到HD 80606 b的任何射电辐射，并利用这些观测结果对它的射电光度进行了新的限制。我们还重新审视是否进行了观测的时候，它是超阿尔夫文相对于主恒星的恒星风，经验从太阳系说明是一个国家，其中电子回旋脉泽发射可以持续在行星的磁极区。
英文摘要：
All the giant planets in the solar system generate radio emission via the electron cyclotron maser instability, most notably giving rise to Jupiter's decametric emissions. An interaction with the solar wind is at least partially responsible for all of these solar system electron cyclotron masers. HD80606b is a giant planet with a highly eccentric orbit, leading to predictions that its radio emission may be enhanced substantially near periastron. This paper reports observations with the Low Frequency Array (LOFAR) of HD80606b near its periastron in an effort to detect radio emissions generated by an electron cyclotron maser instability in the planet's magnetosphere. The reported observations are at frequencies between 30 MHz and 78 MHz, and they are distinguished from most previous radio observations of extrasolar planets by two factors: (i) They are at frequencies near 50 MHz, much closer to the frequencies at which Jupiter emits (< 40 MHz) and lower than most previously reported observations of extrasolar planets; and (ii) Sensitivities of approximately a few millijanskys have been achieved, an order of magnitude or more below nearly all previous extrasolar planet observations below 100 MHz. We do not detect any radio emissions from HD80606b and use these observations to place new constraints on its radio luminosity. We also revisit whether the observations were conducted at a time when it was super-Alfvenic relative to the host star's stellar wind, which experience from the solar system illustrates is a state in which an electron cyclotron maser emission can be sustained in a planet's magnetic polar regions.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
