International Research Fellow Awards: Spiral Galaxy Disks; Dust Control, Spiral Structure, and Star Formation

9902653Gonzalez国际研究员奖励计划使美国科学家和工程师能够在国外进行三到二十四个月的研究。 该计划的奖项提供了联合研究的机会，以及使用独特或互补的设施，专业知识和国外的实验条件。冈萨雷斯与支持24个月的工作在天文台德热内夫在大学德热内夫在索维尼，瑞士，与一组研究人员领导的博士。 Gonzalez博士将应用两种原创的成功的光度测量方法来解决两个重要而悬而未决的问题：螺旋星系盘的尘埃含量和分布，以及螺旋结构本身的性质和驱动机制。 她将使用她开发的一种名为“合成场方法”的方法，通过附近螺旋星系的圆盘，从背景星系的颜色和数量来测量平均总消光。这将是迄今为止最大规模的关于螺旋星系完全灭绝的研究，并将允许第一次无反射地确定星系盘中尘埃的径向分布。 通过将光学和近红外数据结合到一个无红化、超巨星敏感的光度参数中，并将结果与恒星种群合成模型进行比较，她将搜索方位角恒星梯度，并测量螺旋图案的角速度（在不同的星系样本中）。 她的目标是获得螺旋星系中恒星成分密度波频率的第一批统计数据。日内瓦天文台设有机械和计算机车间、仪器校准实验室和一个计算机中心。 它积极参与欧洲南方天文台和欧洲航天局的工作。 参与ESO将为Gonzalez博士提供独特的望远镜设施。 Pfenniger博士发表了大量关于星系动力学的文章。

9902653GonzalezThe International Research Fellow Awards Program enables U.S. scientists and engineers to conduct three to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.This award will provide Dr. Rosa A. Gonzalez with support for twenty-four months to work at the Observatoire de Geneve at the Universite de Geneve in Sauverny, Switzerland, with a group of researchers led by Dr. Pfenninger. Twelve months is being supported by NSF's Directorate for Mathematical and Physical Sciences' Office of Multidisciplinary Activities.Dr. Gonzalez will apply two original and successful photometric methods to address two important and outstanding questions: the dust content and distribution of spiral galaxy disks, and the nature and driving mechanisms of spiral structure itself. She will use a method she has developed called "Synthetic Field Method" to measure average total extinction through the disks of nearby spiral galaxies, from colors and counts of background galaxies. This will be the largest study to date of total extinction in spirals, and will allow the first assumption-free determination of the radial distribution of dust in galaxy disks. By combining optical and near-infrared data into a reddening-free, supergiant-sensitive photometric parameter, and comparing the results to stellar population synthesis models, she will search for azimuthal stellar gradients and measure the angular velocity of the spiral pattern (in a different sample of galaxies). Her goal is to secure the first statistics on the frequency of density waves in the stellar component of spiral galaxies.The Geneva Observatory has mechanic and computer workshops, instrument calibration labs and a computer center. It has an active participation within the European Southern Observatory (ESO) and the European Space Agency. The participation in the ESO will offer Dr. Gonzalez access to unique telescope facilities. Dr. Pfenniger has published extensively on galaxy dynamics.***