RUI: Pulsars and the Interstellar Medium

RUI：脉冲星和星际介质

• 批准号: 9619493
• 负责人: Dan Stinebring
• 金额: $ 14.77万
• 依托单位: Oberlin College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-04-15 至 2001-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9619493&HistoricalAwards=false
• 关键词: RUI; Pulsars; Interstellar; Medium

Abstract Stinebring Turbulence in the interstellar medium provides the support needed to keep the gas from collapsing into a pancake. Evidence from pulsar observations indicates that a turbulent cascade of energy may exist over 12 orders of magnitude in scale size from 10 to the eighth (one hundred million) cm to 100 parsec. This turbulent cascade is not well understood, although high mass stars probably account for much of the energy input to the cascade through stellar winds, ionization, and supernova explosions. In particular, the dissipation of turbulent energy into heat at some scale size less than 10 to the tenth (ten billion) cm must occur, but the details of the mechanism and the physical conditions under which this happens are sketchy. The research to be carried out is aimed at determining the strength of the turbulent cascade at a size scale around 10 to the tenth cm and smaller and to learn more about the dissipation mechanism. The main technique employed will be the observational study of radio pulsar scintillation in the weak scattering regime. This is an opportune time to embark on such a study since both the upgraded Arecibo, Puerto Rico telescope and the soon-to-be-completed Green Bank Telescope will provide outstanding opportunities for pulsar observations above 1 GHz. This is the frequency range in which weak scattering phenomena can be studied effectively. The phenomenon of image-splitting, in which the pulsar image separates into two or more distinct pieces due to scattering in the transition regime between strong and weak scattering, will also be explored. The goals are the same: to better elucidate the strength of the electron inhomogeneity spectrum in the Galaxy and to seek evidence for a dissipation scale. High time resolution studies of bright pulsars will also be undertaken using a well-known VLBI recording system, the S2 system, to obtain baseband sampled data. These observations, which can be conducted at several observat ories (and observing frequencies) simultaneously, will allow high-precision monitoring of pulsar dispersion measures. This provides additional information about the electron inhomogeneities in the Galaxy. As a secondary effort, the baseband sampled data will also be analyzed to study brief and intense radio emission from pulsars in order to better understand the emission physics. Undergraduate students from Oberlin College will be centrally involved in all of these projects and will participate in observations, analysis, and the presentation of the results.

星际培养基中的抽象stinebring湍流提供了防止气体塌陷成煎饼所需的支撑。 脉冲星观察结果的证据表明，湍流的能量级联可能存在于12个数量级以上，从10到第八厘米到100 parsec。尽管高质量恒星可能通过恒星风，电离和超新星爆炸来解释级联反应的大部分能量输入，但这种动荡的级联反应尚未得到充分理解。 特别是，必须发生湍流能量在一定比例的大小小于10到十亿厘米（100亿）厘米的尺寸下耗散成热量，但是机制的细节和发生这种情况的物理条件的细节是粗略的。 要进行的研究旨在确定湍流级联反应的强度，尺寸尺寸约为10至第十cm，较小，并了解有关耗散机制的更多信息。 所采用的主要技术将是弱散射状态中无线电脉冲星闪烁的观察性研究。 这是开始进行此类研究的时机，因为已升级的Arecibo，Puerto Rico望远镜和即将完成的绿色银行望远镜都将为1 GHz以上的Pulsar观察提供出色的机会。 这是可以有效研究弱散射现象的频率范围。 图像分裂的现象也将被探索，其中脉冲星图像分为两个或多个不同的碎片，这也将被探索。目标是相同的：更好地阐明了银河系中电子不均匀性光谱的强度，并寻求耗散量表的证据。 还将使用众所周知的VLBI记录系统S2系统进行亮点脉冲星的高时间分辨率研究，以获取基带抽样的数据。 这些观察结果可以同时在几个观察者（以及观察频率）上进行的观察结果，将允许对PULSAR分散措施进行高精度监测。 这提供了有关银河系中电子不均匀性的其他信息。作为次要工作，还将分析基带采样的数据以研究脉冲星的简短无线电发射，以便更好地了解排放物理。 来自奥伯林学院的本科生将集中参与所有这些项目，并将参与观察，分析和结果的介绍。