Fundamental Characteristics of Very Low Mass Objects

奖项编号：ist - 0606748pi: Gilbor basrii机构：加州大学伯克利分校标题：极低质量物体的基本特征摘要本研究集中于收集观测数据和开发分析工具，以进一步了解极低质量恒星、棕矮星和巨大的系外行星（统称为极低质量物体）的特征。这项工作旨在解决与确定基本参数非常低质量物体（质量、半径、温度、表面重力、成分、旋转和磁场）和大气过程（尘埃形成、磁加热和光谱形成）以及它们的形成、频率和二值性有关的问题。将采用的主要工具是高分辨率光谱学，它将通过“精细分析技术”来开发和校准，以获得单个极低质量物体的基本参数。这些将依次应用于广泛的野外物体和恒星形成区域的物体。此外，这些导出的参数将用于校准和改进极低质量物体的演化模型，既可以了解它们的早期演化，又可以在极低质量物体上更好地利用演化模型来理解恒星形成。对双星中低质量天体的观测将用于更好地理解极低质量天体的双星频率和分离分布，作为测试其形成模式模型的一种手段，并有助于理解在新的参数体系下多天体形成本身的过程。此外，将继续研究低质量天体的自转和活动，方法是进行实际的磁场测量以及对不同类型天体进行更广泛的取样。最后，作为校准M星和早期L星基本参数努力的一部分，将开始研究组成对极低质量天体大气化学和光谱形成的影响。该项目将支持一名新研究生的论文工作，并有助于培养在该小组工作的下一代科学家。巴斯里博士定期通过讲座和媒体进行公众宣传，他在这些领域的活动将继续下去。

AWARD NO: AST-0606748PI: Gilbor BasriINSTITUTION: University of California BerkeleyTITLE: Fundamental Characteristics of Very Low Mass ObjectsABSTRACTThis research centers on the collection of observations and the development of analysistools to further our understanding of the characteristics of very low mass stars, browndwarfs, and giant extrasolar planets (collectively referred to as very low mass objects).The work is intended to address issues with the determination of the fundamentalparameters very low mass objects (mass, radius, temperature, surface gravity,composition, rotation, and magnetic fields) and atmospheric processes (dust formation,magnetic heating, and spectral formation) as well as their formation, frequency and thebinarity. The principle tool to be employed is high resolution spectroscopy which herewill be developed and calibrated through "fine analysis techniques" for obtainingfundamental parameters of single very low mass objects. These will in turn be applied toa broad set of both field objects and objects in star forming regions. Moreover, thesederived parameters will be used to calibrate and improve evolutionary models of verylow mass objects, both to understand their early evolution and to place the use ofevolutionary models in understanding star formation on a better footing for very lowmasses. Observations of low mass objects in binaries will be used to gain a betterunderstanding of the binary frequency and separation distribution of very low massobjects as a means of testing models of their formation modes and to help inunderstanding the process of multi-object formation itself in a new parameter regime. Inaddition, studies of studies of rotation and activity in low mass objects will be continuedby pursuing actual magnetic field measurements as well as a broader sample of differenttypes of objects. Finally, the study of the effects of composition on the atmosphericchemistry and spectral formation in very low mass objects will be begun as part of theeffort to calibrate the fundamental parameters of M and early L stars.This project will support the thesis work of a new graduate student as well as contributeto the training of the next generation of scientists in working in this group. Dr. Basriregularly engages in public outreach through talks and through the media and hisactivities in these areas will continue.