中文摘要：

伽玛暴火球激波模型虽然从整体上形象地说明了爆发后的过程和主要特征,但近年随着观测的深入,似乎也暴露出它在有些方面的考虑可能还不完全,例如它采用同步辐射近似,就相当于承认其磁场基本上是一种均匀场,而均匀场只有单一的一种形态,这无疑就将磁场强弱以外的所有其他重要信息全都抹掉了.尤其在伽玛暴激波中,其密度、压强等物理量都认为是非均匀的,怎么唯独由扰动机制产生的激波磁场又能看成均匀的呢？!本文仔细分析了这一问题，认为激波磁场中磁场弯曲引发的辐射可能才是主体部分，火球激波模型在解释某些最新观测结果时遇到困难，可能正是忽略了这部分辐射的缘故。如果用适合于弯曲磁场的同步-曲率辐射公式，就能很好地拟合一系列伽玛暴谱，统一解释过去难以说明的高能拐点和能量过剩现象，并对辐射区磁场结构、产生机制以及激波加速机制做些初步的推断。

英文摘要：

The frequently cited fireball-shock model of Gamma-Ray Burst （hereafter, GRB） can explain well the main features and processes after the burst. This model, however, is challenged by the latest high-resolution observational results during the last few years, which present some clues on the incompleteness of its theoretical considerations. For example, one basic assumption of the fireball model is using the standard synchrotron radiation mechanism to approximate the high energy emissions from GRBs. This is equivalent to claim that the magnetic field inside GRB is uniformly distributed, which smears out most of the important information of magnetic field configuration other than the field strength. In the study of GRB shocks, it is generally believed that most of the physical quantities, such as density and pressure, are inhomogeneous throughout the shocked region. Then why is it plausible to assume the shocked magnetic field alone to be homogeneous, which originates from perturbation mechanism？ In this paper, we analysis this problem in details, and regard that the radiation induced by curvature of shocked magnetic field lines plays a significant role in GRB emissions. The traditional fireball-shock model meets difficulties in explaining some latest observational results. This may be caused by ignorance of that important portion of radiation above. Making application of the formulae of synchro-curvature radiation, which can treat analytically the particle radiations in the curved magnetic field, we fit well a series of new GRB spectra, and present a unified interpretation toward the turnoff point and energy excess in the high-energy portion of the spectra. These features above are difficult to explain within the past synchrotron radiation framework. Furthermore, the fitting of a series of GRB spectra allows us to give some new constraints on the magnetic structure of the emission district, origin of the shocked magnetc field, and the mechanism of shock acceleration.