Spiral and dwarf galaxies' kinematics and optical instrumentation

螺旋星系和矮星系的运动学和光学仪器

• 批准号: 90037-2006
• 负责人: Carignan, Claude
• 金额: $ 2.91万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2008
• 资助国家: 加拿大
• 起止时间: 2008-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=390764
• 关键词: Spiral; dwarf; galaxies; kinematics; optical

The main goal of our different research projects is to determine the physical parameters (e.g. density laws, total extent) of the Dark Matter present in spiral and dwarf galaxies. The methodology used is the following. First, from 21cm HI observations obtained at the Very Large Array (New-Mexico), Westerbork (Holland), the Australia Telescope, and at DRAO (Penticton, BC), it is possible to derive the rotation curves of those galaxies over 2 to 5 times their optical diameters and thus to measure the mass present out to the last measured velocity point (kinematical mass). Those observations also give us the gas mass, which can sometimes be more important than the stellar mass in certain dwarf galaxies. Then, the light distribution (surface photometry) allows us to derive the stellar mass (using near infrared data, e.g. Spitzer). The difference between the kinematical mass and the luminous mass (stars & gas) is thus a measure of the Dark Matter component. Since the mass models are very sensitive to the rising part of the rotation curves, higher resolution 3D data, obtained from Fabry-Perot interferometry, must be combined to the HI data for the inner parts (to avoid the beam smearing effect of HI data). This is especially important if someone wants to determine whether the dark matter density profiles are flat (e.g. isothermal) or cuspy (e.g. NFW) in the very inner parts, as predicted by Cold Dark Matter cosmological simulations. In order to get the highest Signal-to-Noise data possible in the very critical inner parts, we built our own Image Photon Counting System (IPCS) called FaNTOmM, which we used not only on the 1,6m telescope of the Observatoire du mont Mégantic, but also on the 3,6m telescopes of the Canada-France-Hawaii (CFHT) and of the ESO (La Silla). The first generation of FaNTOmM used a GaAs intensifier tube which gives a DQE ~ 30% (meaning that 30% of the incoming photons are detected), as compared to ~4-5% for the old IPCS and we are working on the second generation camera based on a L3CCD chip which should provide a DQE > 80%.

我们不同的目标是确定物理参数（例如，密度定律，总范围）和矮星系。 ，西方（荷兰），澳大利亚望远镜和在五到5倍光直径的2至5倍的软管星系，因此要测量您的质量，而不是恒星的最后一个测得的速度点。然后，某些矮人的星系中的质量。由于质量模型对旋转曲线的上升部分非常敏感，因此从Fabry-Perot干涉法获得的更高分辨率3D数据必须合并到HI数据中，以使其内部零件EAM涂抹效果的HI数据尤其重要。如果某人想确定深色暗物质宇宙模拟所预测的暗物质密度曲线是否是平坦的（例如NFW）。零件，我们构建了称为Fantoms IC的图像光子计数系统（IPC），但在加拿大 - 弗朗西 - 弗朗西·霍瓦伊（CFHT）和ESO（LA Silla）的36m望远镜上也是如此。检测到DQE〜30％ONS的管），相比之下，旧IPC 〜4-5％，我们正在基于第二代摄像机的工作。