本学位论文主要围绕伽马射线暂现源开展研究，研究的对象包括来自天体的伽马射线暴（Gamma-ray Burst，简称GRB）、软伽马射线重复暴（Soft Gamma Repeater，简称SGR）、太阳耀斑（Solar Flare，简称SFL）等，和来自地球的地球伽马闪（Terrestrial Gamma-ray Flash，简称TGF）和地球电子束（Terrestrial Electron Beam，简称TEB）等，研究内容包括搜索、鉴别、性质统计和定位等，主要使用的数据来自观测仪器：怀柔一号极目卫星（即，引力波暴高能电磁对应体全天监测器，Gravitational-wave high-energy Electromagnetic Counterpart All-sky Monitor，简称GECAM）和费米伽马射线望远镜的伽马射线爆发监视器（Gamma-ray Burst Monitor aboard the Fermi Gamma-ray Space Telescope，简称Fermi/GBM）。主要成果包括：

（1）GECAM地球伽马闪和地球电子束研究。TGF是亚毫秒时标的伽马射线波段的剧烈爆发，若TGF在传播的过程中跟大气发生相互作用，则可能产生次级电子或者正电子，即TEB。目前探测到的TEB是比较罕见的，在近15年里总共报道了仅~30例TEB事件。依托GECAM的创新性设计，例如，时间分辨率高（100 ns）、探测能量范围宽（~15 keV-~5 MeV）、抗数据饱和的硬件设计、搭载了能够探测电子的探测器等，本学位论文设计了一种GECAM的TGF/TEB搜索算法，在~9个月的数据里，搜索到了147个亮的TGF事件、2个典型的TEB事件和2个TEB-like事件。比较重要的发现包括：GECAM的TGF事件和GLD360闪电的关联率达到~80%，显著的高于其它空间仪器和WWLLN数据进行闪电关联得到的结果（~33%）；报道了全球首例四峰TEB-like事件。

（2）计数调制定位方法研究，主要研究了定位过程里的三个问题。首先，为了给弱源定位，本学位论文提出一种贝叶斯定位方法，蒙卡模拟表明该方法在弱源定位中有一定的优势。然后，为了缓解定位所用的能谱和真实能谱的不匹配问题，提出一种能谱-位置迭代的定位策略，蒙卡模拟表明该策略可以在一定程度上缓解能谱不匹配的问题。最后，因为传统的贝叶斯定位系统误差估计方法采用了高斯假设，所以当统计误差区域非高斯时的系统误差估计是不准确的，因此提出一种基于置信度检验的系统误差估计方法，蒙卡模拟表明本文提出的估计方法可以准确估计系统误差。

（3）为了评估GECAM的定位能力，本学位论文对23个亮且有外部准确参考位置的GECAM爆发事件（包括9个GRB事件、12个SGR事件、2个SFL事件）进行了GECAM实测定位研究。其中，3个流量~1*10^-5 erg/cm2的亮GRB事件的1 sigma统计误差是~2度，跟GECAM卫星设计的定位指标是基本符合的，该实测结果初步表明GECAM达到了其设计的定位指标。根据选择的23个爆发事件和基于置信度检验的系统误差估计方法，计算得到GECAM的定位系统误差是~2.5度。这是首次报道的GECAM定位系统误差估计值。

This thesis primarily focuses on the study of gamma-ray transient sources, encompassing astronomical events such as Gamma-ray Burst (GRB), Soft Gamma-ray Repeater (SGR), and Solar Flare (SFL), as well as terrestrial phenomena like Terrestrial Gamma-ray Flash (TGF) and Terrestrial Electron Beam (TEB). The research includes search, identification, statistics of source properties, and localization. The primary data used in this study are from the Huairou-1 Satellite (i.e. Gravitational-wave high-energy Electromagnetic Counterpart All-sky Monitor, GECAM) and the Gamma-ray Burst Monitor aboard the Fermi Gamma-ray Space Telescope (Fermi/GBM). The main achievements of this thesis include:

(1) Research of TGFs and TEBs detected by GECAM. TGFs are intense bursts in the gamma-ray band with sub-millisecond timescales. If TGFs interact with the atmosphere during propagation, they may produce secondary electrons or positrons, known as TEBs. Currently, detected TEBs are relatively rare, with only approximately 30 reported cases in the past 15 years. This research utilizes the innovative design of GECAM, including high time resolution (100~ns), a wide energy range (~15~keV to ~5~MeV), hardware design resistant to data saturation, and detectors capable of detecting electrons. A TGF/TEB search algorithm for GECAM has been proposed in this thesis. Analysis of ~9 months of data led to the discovery of 147 bright TGFs, 2 typical TEBs, and 2 TEB-like events. Notable findings include: the matched ratio between GECAM TGFs and GLD360 lightning reaches ~80%, which is significantly higher than the matched ratio obtained using other space instruments and WWLLN lightning data (~33%); and a quad-peaked TEB-like event was discovered, which is the first reported occurrence of its kind.

(2) Research of localization method based on counts distribution. Firstly, a Bayesian localization method was proposed to locate weak sources, and Monte Carlo simulations demonstrated its effectiveness in weak source localization. Secondly, a localization strategy based on location-spectrum iteration was proposed to alleviate the mismatch between the spectral parameters used in localization and the true source spectra. Monte Carlo simulations showed that this strategy can effectively address the mismatch. Thirdly, it was observed that traditional Bayesian systematic error estimation approach requires Gaussian assumption, which may lead to inaccurate estimates for non-Gaussian error regions. To address this issue, a systematic error estimation method based on confidence tests was proposed, and Monte Carlo simulations showed that this method can accurately estimate systematic errors.

(3) A research was conducted to evaluate the localization capability of GECAM. Specifically, 23 bright GECAM bursts (including 9 GRBs, 12 SGRs, and 2 SFLs) with accurate reference locations were selected for analysis. Among them, the 1 sigma statistical error for 3 bright GRBs (fluence ~1*10^-5 erg/cm2) was found to be ~2 deg, which is consistent with the localization designs of the GECAM satellite. Based on the selected 23 bursts, the systematic error of GECAM localization was estimated to be ~2.5 deg, which is the first reported estimation of the GECAM localization systematic error.