论文标题
原始喷气机的无线电光谱：热和非热发射
Radio spectra of protostellar jets: Thermal and non-thermal emission
论文作者
论文摘要
原始喷气机和流出是恒星形成的指针，它是动量和能量转移到星际介质的重要来源。从电离喷气机发射的无线电发射已被检测到许多原始物体。在少数情况下，还观察到负光谱指数和极化发射，这表明存在相对论电子的同步加速器发射。在这项工作中，我们开发了一个数值模型，该模型既包含了射流几何形状中的无热自由和非热同步发射机制。通量密度包括内部热射流的贡献，以及沿边缘和四肢的热和非热分布发射的组合，射流与星际介质相互作用。我们还包括整个射流横向的电离分数的效果。对射流的无线电发射和光谱的研究显示了沿视线的发射过程和光学深度的依赖性。我们探讨了各种参数对与之相关的离职频率和无线电频谱指数（在10 MHz和300 GHz之间）的影响。
Protostellar jets and outflows are pointers of star-formation and serve as important sources of momentum and energy transfer to the interstellar medium. Radio emission from ionized jets have been detected towards a number of protostellar objects. In few cases, negative spectral indices and polarized emission have also been observed suggesting the presence of synchrotron emission from relativistic electrons. In this work, we develop a numerical model that incorporates both thermal free-free and non-thermal synchrotron emission mechanisms in the jet geometry. The flux densities include contribution from an inner thermal jet, and a combination of emission from thermal and non-thermal distributions along the edges and extremities, where the jet interacts with the interstellar medium. We also include the effect of varying ionization fraction laterally across the jet. An investigation of radio emission and spectra along the jet shows the dependence of the emission process and optical depth along the line of sight. We explore the effect of various parameters on the turnover frequencies and the radio spectral indices (between 10 MHz and 300 GHz) associated with them.
