Global kinetic modeling of the intrabinary shock in spider pulsars

蜘蛛脉冲星双星内激波的全局动力学模型

• 批准号: 2307202
• 负责人: Lorenzo Sironi
• 金额: $ 52.77万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2307202&HistoricalAwards=false
• 关键词: Global; kinetic; modeling; intrabinary; shock

Among the most fascinating astrophysical objects are the “spider pulsars,” which are a particular type of very rapidly-rotating, extremely compact neutron stars in a binary system. Spider pulsars, which are classified as either Redbacks (RBs) or Black Widows (BWs), are in tight binary orbits with a low-mass stellar companion. The pulsar emanates an intense relativistic wind. When impacting on the companion star, the wind exacerbates ablation and mass loss of the companion, which is then “devoured” by the pulsar wind --- hence, the evocative name of these systems. A research team at Columbia University will use state-of-the-art computer simulations to better understand spider pulsars, and astrophysical shock waves in general. The lead researcher will also design a new course, “Back-of-the-envelope physics, astronomy, and beyond," to introduce students in the Columbia Bridge to Ph.D. scholars program to the art of looking at reality with quantitative eyes, using personal experience and prior knowledge as a guide to drawing order-of-magnitude conclusions, and thus to being prepared to make decisions that are grounded in quantitative reasoning.The relativistic pulsar wind consists of toroidal stripes of opposite magnetic field polarity, separated by current sheets of hot plasma. The wind terminates in a strong shock, where the ram pressure of the pulsar wind is balanced by the companion wind or its magnetosphere. The intrabinary shock may be an efficient site of particle acceleration, which would then explain why X-ray and gamma-ray lightcurves of spider pulsars are often modulated on the orbital period. Therefore, the scrutiny of BWs and RBs can help uncover the largely unknown physics of pulsar winds in millisecond pulsars, and aid in understanding where the transition occurs from a Poynting flux-dominated to a particle-dominated flow. This project will involve first-principles global kinetic Particle-In-Cell simulations of the intrabinary shock in spider pulsars, so one can simultaneously capture the microscopic physics of magnetic field dissipation, particle acceleration and ensuing emission, as well as the global morphology and curvature of the shock and the resulting macroscopic flow dynamics. While the main focus is on spider pulsars, the question of particle acceleration in magnetically-dominated striped shocks is of profound relevance to the physics of Poynting-flux-dominated relativistic outflows in other systems, like jets of active galactic nuclei and gamma-ray bursts. This award advances the goals of the Windows on the Universe Big Idea.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

最引人入胜的天体物理物体是“蜘蛛脉冲星”，它们是二元系统中非常快速的，非常紧凑的中性恒星的特定类型。蜘蛛脉冲星被归类为红背（RB）或黑寡妇（BWS），在紧密的二进制轨道上，具有低质量恒星伴侣。脉冲星散发出强烈的相对论风。当影响伴侣恒星时，风加剧了同伴的消融和质量损失，然后被脉冲星风“吞噬”，因此，这些系统的令人回味的名称。哥伦比亚大学的研究团队将使用最先进的计算机模拟来更好地了解蜘蛛脉冲星和天体物理冲击波。首席研究人员还将设计一门新课程，即“底层物理学，天文学及其他人”，向哥伦比亚桥的学生介绍博士学位。学者们以定量的眼光来看待现实，利用个人经验和先验知识来绘制刻录顺序结论的指南，因此准备做出基于定量推理的决策。相对论的脉冲星风由相反的磁场极性组成，由相反的磁场极性组成，由当前热等离子体的当前板隔开。风在强烈的冲击中终止，其中脉冲风的RAM压力与伴侣风或磁层平衡。内部冲击可能是颗粒加速度的有效位点，然后解释了为什么在轨道时期通常会调节蜘蛛脉冲星的X射线和伽马射线灯弯曲。因此，对BWS和RB的审查可以帮助揭示毫秒脉冲脉冲中脉冲星风的主要未知物理，并有助于理解从以颗粒为主的流量为主导的流量为颗粒的流量而发生的过渡。该项目将涉及蜘蛛脉冲星中静脉冲击的第一原理，因此可以简单地捕获磁场耗散，颗粒加速度和发射的显微镜物理学，以及减震器的全球形态和曲率，并产生震动的曲率和结果循环流动流动动力学。虽然主要的重点是蜘蛛脉冲星，但磁性的条纹冲击中的粒子加速度问题与其他系统中的po频畅性相对论媒体的物理学具有深远的相关性，例如主动银河核和伽马射线爆发的喷射。该奖项推动了宇宙中窗户的目标。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子优点和更广泛的影响审查标准来评估被认为是宝贵的支持。