Dynamic relationship between proton and electron auroral substorms
Dynamic relationship between proton and electron auroral substorms
复制标题
质子和电子极光亚暴之间的动态关系
DOI：
10.1029/ja080i004p00553
复制
发表时间：
1975
影响因子：
--
通讯作者：
H. Fukunishi
中科院分区：
文献类型：
--
作者：
H. Fukunishi
1970年3月至10月，在南极洲的Syowa站（校正地磁纬度，−66.7°;经度，72.5°）对质子极光和电子极光的动力学行为进行了同步观测。氢的巴耳末β（Hβ）被选为质子极光的典型发射线，而N2+ 4278-A，O I 5577-A和O I 6300-A的发射被选为电子极光。Hβ光度计有一个倾斜滤光片，用于测量没有强电子极光污染的微弱质子极光的快速时空变化，而其他光度计有固定的干涉滤光片。利用这些电子扫描光度计的记录，详细研究了质子和电子极光亚暴的发展特征。结果表明，在亚暴膨胀相开始前的一段时间内，质子极光的发射带以100-250 m/s的速度向赤道方向移动，并伴随着环流的发展。在膨胀相开始时，平静弧突然变亮，一般在午夜前区域，电子极光隆起迅速向极向和向西扩展。在午夜后的区域，质子极光的发射带迅速向极向扩展，光度大幅增加。在膨胀的电子极光隆起的前缘没有质子极光，而在膨胀的质子极光隆起中没有观察到分裂型电子极光（弧或带）。因此，我们认为存在一种机制，使午夜前区域的电子和午夜后区域的质子沿沿着地磁场线向下加速到电离层。膨胀相开始后，质子极光的亮度在黄昏区大大增加，同时，发射带向赤道方向扩展，伴随着不对称的部分环流和正海湾的发展。这一关系表明，夜区质子极光的源是注入的环流质子。
The simultaneous observations of the dynamic behavior of proton and electron auroras were carried out from March to October 1970 at Syowa station (corrected geomagnetic latitude, −66.7°; longitude, 72.5°) in Antarctica. The hydrogen Balmer beta (Hβ) was selected as a typical emission line from proton auroras, whereas N2+ 4278-A, O I 5577-A, and O I 6300-A emissions were selected for electron auroras. The Hβ photometer has a tilting filter to measure rapid space-time variations of faint proton auroras free from the contamination of strong electron auroras, whereas the other photometers have fixed interference filters. By means of the records of these meridian-scanning photometers the developing features of the proton and electron auroral substorms are investigated in detail. It is found that during the period preceding the onset of a substorm expansion phase the emission zone of the proton aurora moves equatorward with a speed of 100–250 m/s, accompanying the development of the ring current. It is also found that at the onset of the expansion phase the quiet arcs suddenly brighten generally in the premidnight region and the electron auroral bulge rapidly expands poleward and westward. In the postmidnight region it is observed that the emission zone of proton auroras rapidly expands poleward with a large increase in luminosity. Proton auroras are absent in the leading edge of the expanding electron auroral bulge, whereas breakup-type electron auroras (arcs or bands) are not observed in the expanding proton auroral bulge. Therefore it is suggested that there is a mechanism that accelerates electrons in the premidnight region and protons in the postmidnight region along the geomagnetic field lines down to the ionosphere. After the onset of the expansion phase the luminosity of the proton aurora greatly increases in the evening region, and simultaneously, the emission zone expands equatorward, accompanying the development of the asymmetric partial ring current and the positive bay in this local time region. This relation indicates that the source of the proton aurora in the evening region is the injected ring current protons.