Exploring the powering source of the TeV X-ray binary LS 5039
J. Moldon, M. Ribo, J. M. Paredes, J. Marti, M. Massi
备注：
6 pages, 1 figure. Needs PoS.cls. Contributed talk at The 9th European VLBI Network Symposium on The role of VLBI in the Golden Age for Radio Astronomy and EVN Users Meeting, September 23-26, 2008, Bologna, Italy
LS 5039是迄今为止发现的四颗TeV发射X射线双星之一。其多波长发射的动力源可以是微类星体场景中的吸积或年轻非吸积脉冲星场景中的风相互作用。这两个方案预测不同的形态和峰值位置的变化沿轨道周期的3.9天，这可以测试在毫角秒尺度上使用VLBI技术。在这里，我们提出了一个运动的5 GHz VLBA观测在2000年6月进行（2运行5天间隔）。结果表明，核心组件具有恒定的通量密度，和一个快速变化的形态和位置角的细长的扩展发射，但保持一个稳定的通量密度。这些结果很难在微类星体的情况下舒适地拟合，而它们似乎与非吸积脉冲星的预测行为相兼容。
英文摘要：
LS 5039 is one of the four TeV emitting X-ray binaries detected up to now. The powering source of its multi-wavelength emission can be accretion in a microquasar scenario or wind interaction in a young non-accreting pulsar scenario. These two scenarios predict different morphologic and peak position changes along the orbital cycle of 3.9 days, which can be tested at milliarcsecond scales using VLBI techniques. Here we present a campaign of 5 GHz VLBA observations conducted in June 2000 (2 runs five days apart). The results show a core component with a constant flux density, and a fast change in the morphology and the position angle of the elongated extended emission, but maintaining a stable flux density. These results are difficult to fit comfortably within a microquasar scenario, whereas they appear to be compatible with the predicted behavior for a non-accreting pulsar.
PS15dpn is a luminous rapidly rising Type Ibn supernova (SN) discovered by Pan-STARRS1 (PS1). Previous study showed that its bolometric light curve (LC) cannot be explained by the $^{56}$Ni model. In this paper, we used the $^{56}$Ni model, the magnetar model, the circumstellar interaction (CSI) model, and the CSI plus $^{56}$Ni model to fit the bolometric LC of PS15dpn. We found that the $^{56}$Ni model can fit the bolometric LC but the parameters are unrealistic, and that the magnetar model, the CSI model, and the CSI plus $^{56}$Ni model can match the data with reasonable parameters. Consid…
Microquasar Cygnus X-3 as the PeVatron powering the Cygnus Bubble
University of Science and Technology of China（中国科学技术大学）；Yerevan State University（埃里温国立大学）；TIANFU Cosmic Ray Research Center（天府宇宙线研究中心）；Max-Planck-Institut for Nuclear Physics（马克斯·普朗克核物理研究所）
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Nanjing University（南京大学）；Tsung-Dao Lee Institute, Shanghai Jiao Tong University（上海交大李政道研究所）；Key Laboratory of Modern Astronomy and Astrophysics, Nanjing University, Ministry of Education（南京大学现代天文与天体物理教育部重点实验室）；School of Physics and Astronomy, Shanghai Jiao Tong University（上海交通大学物理与天文学院）
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