High Resolution Studies of Solar Flares, Active Regions, Prominences and the Quiet Sun at Centimeter and Millimeter Wavelengths

厘米和毫米波长下太阳耀斑、活动区域、日珥和安静太阳的高分辨率研究

• 批准号: 9316972
• 负责人: Mukul Kundu
• 金额: $ 45.76万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-03-01 至 1997-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9316972&HistoricalAwards=false
• 关键词: Resolution; Studies; Solar; Flares; Active

9316972 Kundu This effort continues research at the University of Maryland centered around the study of solar flares using radiowave techniques. The investigators will use observations made by the Very Large Array (VLA) of the National Radio Astronomy Observatory, and the Berkeley-Illinois-Maryland Millimeter Array (BIMA) at Hat Creek. The investigators will compare the observed magnetic structure of sunspot-associated microwave sources with model computations and determine the vertical and horizontal components of the magnetic field at specific locations in the low corona. The study will also make use of X-ray and EUV data obtained by the Yohkoh satellite. The combined data will be used to estimate the electron temperature and magnetic field in coronal loops, and the temperature and density structure of the active region in three dimensions. VLA observations of flares at multiple centimeter wavelengths will be used to study the structure and cause of flaring. The BIMA observations will provide high spatial resolution measurements of flares at millimeter wavelengths. In particular, the millimeter imaging observations of MeV electrons will be used to study gamma ray sources sizes, structures and locations. The similarity of time profiles of impulsive emission by MeV electrons will permit us to analyze the fundamental characteristics of the acceleration mechanism responsible for MeV electrons. The delay of millimeter emission relative to cm, hard X-rays and gamma rays will provide important information on electron and proton acceleration. Additionally, the investigators will search for nanoflares and acoustic waves in the Sun's chromosphere and study chromospheric and coronal heating.***

这项工作继续在马里兰大学进行，研究的中心是利用无线电波技术研究太阳耀斑。研究人员将使用国家射电天文台的甚大阵列（VLA）和Hat Creek的伯克利-伊利诺伊-马里兰毫米波阵列（BIMA）进行观测。研究人员将把观测到的与太阳黑子相关的微波源的磁结构与模型计算进行比较，并确定低日冕特定位置磁场的垂直和水平分量。这项研究还将利用Yohkoh卫星获得的x射线和极紫外数据。综合数据将用于估算日冕环内的电子温度和磁场，以及活动区域的三维温度和密度结构。VLA对多厘米波长耀斑的观测将用于研究耀斑的结构和成因。BIMA观测将提供毫米波长耀斑的高空间分辨率测量。特别是，MeV电子的毫米成像观测将用于研究伽马射线源的大小、结构和位置。MeV电子脉冲发射时间谱的相似性将使我们能够分析产生MeV电子的加速机制的基本特征。毫米发射相对于厘米、硬x射线和伽马射线的延迟将提供电子和质子加速的重要信息。此外，研究人员将在太阳的色球层中寻找纳米耀斑和声波，并研究色球层和日冕的加热