CAJ | 학술논문

目前观测的CME(日冕物质抛射)是其在天空平面的投影,这就导致CME的观测参量与真实参量之间存在一定的差异,比如说观测到的CME速度一般要比CME的真实速度小.运用基于锥状模型对CME的速度进行投影改正的方法,分析1996年9月到2007年9月(将近1个活动周)SOHO/LASCO日冕仪观测到的1 691个仅与耀斑相关的CME(简称FL类CME)和610个仅与暗条爆发相关的CME(简称FE类CME)投影改正前后的速度分布,得到如下结果:(1)投影改正前后,FL类CME和FE类CME的速度分布非常相似.且投影改正前后,两类CME的平均速度几乎相同; (2)投影改正前后,FL类CME和FE类CME速度的自然对数分布也非常相似.
목전관측적CME(일면물질포사)시기재천공평면적투영,저취도치CME적관측삼량여진실삼량지간존재일정적차이,비여설관측도적CME속도일반요비CME적진실속도소.운용기우추상모형대CME적속도진행투영개정적방법,분석1996년9월도2007년9월(장근1개활동주)SOHO/LASCO일면의관측도적1 691개부여요반상관적CME(간칭FL류CME)화610개부여암조폭발상관적CME(간칭FE류CME)투영개정전후적속도분포,득도여하결과:(1)투영개정전후,FL류CME화FE류CME적속도분포비상상사.차투영개정전후,량류CME적평균속도궤호상동; (2)투영개정전후,FL류CME화FE류CME속도적자연대수분포야비상상사.
Observations of coronal mass ejections (CMEs) with coronagraphs are subject to the projection effect, which results in statistical errors in many properties of CMEs, such as the speed. In this paper, using the method based on the cone model to correct the speeds of CMEs due to the projection effect, we study the speed distribution of CMEs before and after correction for 1691 CMEs only associated with flares (type-FL CMEs) and 610 CMEs only associated with filament eruptions (type-FE CMEs) observed by the Large Angle and Spectrometric Coronagraph Experiment on board the Solar and Heliospheric Observatory (SOHO/LASCO) from September 1996 to September 2007, corresponding to almost an entire solar cycle. The results are concluded as follows: (1) before and after the correction, type-FL and type-FE CMEs have quite similar distribution of speed with almost the same average speed; (2) before and after the correction, type-FL and type-FE CMEs have quite similar distribution of the natural logarithm of speed. Our results do not favor that CMEs should be classified into two distinct types, i.e. slow CMEs that are associated with filament eruptions and fast CMEs associated with solar flares.