Uncovering the Nature of Lyman-alpha Nebulae in the Distant Universe

该奖项由2009年美国复苏与再投资法案(公法111-5)资助。扎布卢多夫博士将研究莱曼-阿尔法团，这是遥远宇宙中的一大团发光气体，可能代表着当今最明亮星系的青春期。她和她的团队将完成两个相辅相成的盲目调查，以寻找太遥远的莱曼-阿尔法斑点，以至于我们看到它们在大爆炸后只有30亿年。这些测量将使用窄带滤光片，使用斯图尔德2.3米望远镜和国家光学天文台两个4米望远镜上的宽视场成像器。用较小的望远镜进行的浅而超宽的探测针对的是最稀有、最明亮的斑点，而用4米长的望远镜进行的探测将更深，以探测更多较暗的斑点。然后，扎布卢多夫博士将在光学和红外波长上获取最亮的斑点的光谱，以测量气体运动，并限制温度、密度和化学成分。通过比较不同谱线的轮廓，可以看出发光的气体是坠入还是以星系风的形式吹出。将这些观测结果与模型进行比较，将会发现莱曼-阿尔法团是否可能是吸积气体的新生星系。一名研究生和一名本科生将通过参与这项研究进行培训。扎布卢多夫博士将把研究结果纳入本科生的课堂练习中。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Dr Zabludoff will study Lyman-alpha blobs, large clouds of glowing gas in the distant Universe that may represent the adolescence of today's brightest galaxies. She and her team will complete two complementary, blind surveys to search for Lyman-alpha blobs so distant that we see them as they were only 3 billion years after the Big Bang. These surveys will use a narrow-band filter with the wide-field imagers on the Steward 2.3-meter telescope and the two 4-meter telescopes of the National Optical Astronomy Observatory. The shallow but ultra-wide survey with the smaller telescope targets the rarest, most luminous blobs, while the survey with the 4-meter telescopes will be deeper to detect the more numerous fainter blobs. Dr Zabludoff will then take spectra of the brightest blobs at optical and infrared wavelengths, to measure the gas motions and to constrain the temperature, density and chemical composition. Comparing profiles of the different spectral lines will show whether the glowing gas is falling in, or blowing out as a galactic wind. Comparing these observations with models will show whether the Lyman-alpha blobs are likely to be gas-accreting nascent galaxies.A graduate student and an undergraduate will be trained by participating in the research. Dr Zabludoff will incorporate results from the research into classroom exercises for undergraduate students.