摘要
对１９８８年６月２９日云南天文台高时间分辨率射电望远镜观测到的微波超快速吸收现象进行了分析研究。在世界时０７ｈ３８ｍ５０ｓ至０７ｈ３８ｍ５８ｓ超快速吸收现象出现在太阳活动区ＮＯＡＡ／ＵＳＡＦ５０６０上空的４００ＧＨｚ上，而在２８４ＧＨｚ和１４２ＧＨｚ上空出现的是ｓｐｉｋｅ辐射。当时，该活动区呈现出极其活跃的双极磁场位形。在世界时０７ｈ３８ｍ至０８ｈ４７ｍ先后产生了３Ｂ级和２Ｂ级的Ｈα耀斑，并出现了Ｍ６５Ｘ射线爆发。根据电子回旋脉泽谐波吸收峰的特性，我们计算了三个波段的二次、三次谐波的磁场强度，并采用偶极磁场模型进行分析。对于４００ＧＨｚ上出现的超快速吸收现象，可能是产生的三次谐波脉泽辐射，在穿过吸收区时被吸收掉了。
In this paper, a microwave ultra-fast absorption phenomenon observed with high time resolution on June 29, 1988 is analyzed. This absorption appeared at the atmospheric layer of 4 00 GHz above solar active region of NOAA/USAF 5060 from 07 h38 m50 s to 07 h38 m58 s UT. At atmospheric layers of 2 84 GHz and 1 42 GHz spike emissions appeared. AR5060 was of the configuration of bipolar magnetic field which had strong activity. Hα flares of 3B and 2B were generated from 07 h38 m to 08 h47 m UT. X-ray burst of M6 5 also occurred. According to the characteristics of harmonic absorption peak of ECM, we have calculated the magnetic field of harmonic, S=2,3, at three frequencies (4 00 GHz, 2 84 GHz and 1 42 GHz) and analysed the absorption by using the bipolar field model. It is possible that the third harmonic of ECM at frequency of 4 00 GHz, was absorbed when it passed the absorption region (Ω e=ω/3).
出处
《云南天文台台刊》
CSCD
1998年第1期33-40,共8页
Publications of the Yunnan Observatoty
