Synchrotron emission polarization is very sensitive to the magnetic field configuration. Recently, polarization of synchrotron emission with a mixed (SM) magnetic field in the gamma-ray burst (GRB) afterglow phase has been developed. Here, we apply these SM models to the GRB prompt phase and compare their polarization properties with that of synchrotron emission in purely ordered (SO) magnetic field. We find that the polarization properties in an SM model are very similar to these in a corresponding SO model (e.g., synchrotron emission in a mixed magnetic field with an aligned ordered part (SMA) and synchrotron emission with a purely ordered aligned magnetic field (SOA)), only with a lower polarization degree (PD). We also discuss the statistical properties of the models. We find PDs of the simulated bursts are concentrated around 25% for both SOA and synchrotron emission in a purely ordered toroidal magnetic field (SOT), while they can range from 0% to 25% for SMA and synchrotron emission in a mixed magnetic field with a toroidal ordered part (SMT), depending on ξ_B value, i.e., the ratio of magnetic reduction of the ordered magnetic field over that of random magnetic field. From statistics, if PDs of majority GRBs are non-zero, then it favors SO and SM models. Further, if there are some bright GRBs with prominently lower PDs than that of the majority GRBs, it favors SOT (SMT) models; if all the bright GRBs have comparable PDs with the majority ones, it favors SOA (SMA) models. Finally, we apply our results to POLAR’s data and find that ∼ 10% time-integrated PDs of the observed bursts favor SMA and SMT models, and the ξ_B parameter of these bursts is constrained to be around 1.135.

同步加速器发射极化对磁场配置非常敏感。最近，在伽马射线爆发 (GRB) 余辉阶段，已开发出具有混合 (SM) 磁场的同步加速器发射极化。在这里，我们将这些 SM 模型应用于 GRB 瞬发阶段，并将它们的极化特性与纯有序 (SO) 磁场中的同步加速器发射的极化特性进行比较。我们发现 SM 模型中的极化特性与相应的 SO 模型中的极化特性非常相似（例如，具有对齐有序部分 (SMA) 的混合磁场中的同步辐射和具有纯有序对齐磁场 (SOA) 的同步辐射))，仅具有较低的极化度 (PD)。我们还讨论了模型的统计特性。ξ _B 值，即有序磁场的磁化强度与随机磁场的磁化强度之比。从统计数据来看，如果大多数 GRB 的 PD 不为零，那么它有利于 SO 和 SM 模型。此外，如果有一些明亮的 GRB 的 PD 明显低于大多数 GRB，则有利于 SOT (SMT) 模型；如果所有明亮的 GRB 的 PD 都与大多数 GRB 相当，那么它有利于 SOA (SMA) 模型。最后，我们将我们的结果应用于 POLAR 的数据，发现观测到的爆发的 10% 时间积分 PD 有利于 SMA 和 SMT 模型，并且这些爆发的ξ _B 参数被限制在 1.135 左右。