在地球磁層內，有一種右旋極化的電磁波(RHP WAVES)叫做合唱波，它會沿著磁力線傳播且電磁波頻率大約落在大0.1~0.8倍的電子迴旋頻率之間。合唱波會在內磁層中會與電漿中的粒子產生交互作用，使得環境中周圍的電子產生加速的效應。

本研究聚焦在日側地區進行觀測分析，以西密斯衛星中的其中一顆THEMIS-D衛星在西元2010年所做得觀測，並以高時間解析度的磁場資料作為研究的材料，用以探討合唱波於日側地區出現的次數和機率統計，以及與環境的背景磁場和電子溫度進行比對，從而推測合唱波事件發生時，空間位置與背景參數之間是否有影響。

以空間位置來看，觀測到的數據其結果為與合唱波事件於MLT=15時發生的機率最高為32.5%，在L-parameter落在6~10區間，機率為46.76%機率最高，在geocentric distance落在5~8 (Re)區間，機率為60.00%機率為最高。

以環境背景參數背景磁場強度與電子溫度來看，在日側地區背景磁場強度大小的觀測基礎上，我們發現合唱波事件和無合唱波時段所發生的機率曲線高度重合下，因而推論合唱波事件發生與背景磁場強度沒有太大的關係，若以環境的電子溫度來看，我們會發現若合唱波事件發生，普遍來說，周圍的電子溫度大概只可以被加熱到700eV這個區間範圍，且在低溫區域範圍內(電子溫度小於700eV)時，我們可以總結出一個規律，若有發生合唱波事件的整體機率上溫度偏高。

In the Earth’s magnetosphere, chorus waves are a kind of right-handed polarized(RHP) waves with frequency range between 0.1f_ce and 0.8f_ce, where f_ce is the electron cyclotron frequency.

Chorus waves travel along magnetic field lines and interact with the particles causing electron heating in the space environment. This study focuses on the location of the dayside magnetosphere. The magnetic field data come from one of the THEMIS satellites called THD.

In terms of spatial position, according to the observed data, chorus waves occur with maximum probabilities of 32.50% at magnetic local time(MLT)=15, 46.76% at L-parameter between 6 and 10, 60.00% at geocentric distances between 5 and 8 Earth radii (R_E). In terms of the intensity of the background magnetic field, the probability curves of the chorus wave events and time intervals without waves are highly coincident.

We conclude that chorus wave events do not have much relationship with the background magnetic field magnitude. But based on the electron temperature of the environment, it is found that if chorus waves occur, the surrounding electron temperature is most likely heated up to a range of 700 eV, and in the low-temperature range (electron temperature less than 400 eV), we find the following trend: the higher the temperature, the higher probability of finding a chorus wave event.

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