A Search for Radio Emission from Extrasolar Planets
A Search for Radio Emission from Extrasolar Planets
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寻找太阳系外行星的射电发射
DOI：
10.1086/317864
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
T. Bastian
中科院分区：
文献类型：
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作者：
G. Dulk;Y. Leblanc;T. Bastian
太阳系中所有磁化的行星都会发出强烈的回旋脉泽辐射。像木星一样，太阳系外的巨大行星可能是磁化的。此外，如果在它们的磁层中有一个高能（keV）电子源，来自极光过程或行星与卫星之间的磁耦合，那么太阳系外行星很可能是回旋脉泽发射器。对来自系外行星的回旋脉泽辐射的探测和后续观测将揭示行星磁场的存在、强度和复杂性，行星的自转速率，以及行星磁层内可能存在的类似木卫一的卫星。磁场可能是生命在行星表面生存所必需的，因为它们提供了保护，使其免受恒星风、恒星耀斑和宇宙射线的高能粒子的邪恶影响。我们利用甚大天线阵（VLA）对太阳系外行星和褐矮星的分米和米波长的无线电发射进行了搜索。我们在333和1465 MHz观测到了7颗太阳系外行星和2颗褐矮星，在74 MHz观测到了1颗太阳系外行星和1颗褐矮星。典型的（1 σ）灵敏度在1465 MHz时为0.02-0.07 mJy，在333 MHz时为1-10 mJy，在74 MHz时约为50 mJy。迄今为止，尚未发现任何此类情况。
All magnetized planets in the solar system emit intense cyclotron maser radiation. Like Jupiter, extrasolar giant planets are probably magnetized. If, in addition, there is a source of energetic (keV) electrons in their magnetospheres, from auroral processes or as a result of magnetic coupling between the planet and a satellite, it is likely that extrasolar planets are cyclotron-maser emitters. Detection and follow-up observations of cyclotron maser radiation from an exoplanet would reveal the presence, strength, and complexity of the planetary magnetic field, the planet's rotation rate, and possibly the presence of an Io-like moon within the planet's magnetosphere. Magnetic fields may be necessary for life to exist on the surface of planets because they provide protection from the nefarious effects of energetic particles of stellar winds, stellar flares, and cosmic rays. We have conducted a search for radio emission from extrasolar planets and brown dwarfs at decimeter and meter wavelengths using the Very Large Array (VLA). We have observed seven extrasolar planets and two brown dwarfs at 333 and 1465 MHz, and one extrasolar planet and one brown dwarf at 74 MHz. Typical (1 σ) sensitivities were 0.02-0.07 mJy at 1465 MHz, 1-10 mJy at 333 MHz, and ~50 mJy at 74 MHz. To date, no detections have been made.