Support for observing at the Green Bank 100m Telescope (2)

在3.5毫米左右的波长范围内，正常恒星形成星系的射电辐射预计将由自由-自由机制主导。这种自由辐射通常受到其他射电观测的很弱限制，因为它被波长较长的同步辐射和波长较短的尘埃辐射淹没。因此，绘制大约3.5毫米的正常星系发射图将检查我们对射电发射机制和正常星系模型的物理理解。由于这种观测对表面亮度灵敏度的要求很高，最好使用大型全口径望远镜上的宽带焦平面阵列来完成。我们已经获得了绿岸100米直径望远镜(GBT)试验项目15小时的全职申请，该项目将使用运行在90 GHz的野马测辐射热计相机绘制附近两个星系的地图。到目前为止，GBT是世界上最大的能够工作在90 GHz的望远镜，野马相机是唯一工作在90 GHz的通用相机。我们请求为一人前往现场进行这些初步观测和远程观测程序培训提供支持。根据绿色银行程序的要求，需要亲自前往进行初步观察。此外，这些观测在绝对校准要求和非常干燥和晴朗的天气要求方面将是非常具有挑战性的。

In a range of wavelengths around 3.5 mm, radio emission from normal star-forming galaxies is expected to be dominated by the free-free mechanism. This free-free emission is usually very weakly constrained by other radio observations since it is swamped by synchrotron radiation at longer wavelengths and dust emission at shorter wavelengths. Mapping the emission of normal galaxies at around 3.5 mm will therefore provide a check of our understanding of physics of radio emission mechanisms and models of normal galaxies. Due to the demanding surface-brightness sensitivity requirements of such observations, they are best done using wide-bandwidth focal plane arrays on large filled-aperture telescopes. We have been awarded the full time request of 15 hours for a pilot project at the Green Bank 100-metre diameter telescope (GBT) to map two nearby galaxies with the MUSTANG bolometer camera operating at 90 GHz. The GBT is by far the largest telescope in the world capable of operating at 90 GHz and the MUSTANG camera is the only general-purpose camera operating at 90 GHz. We request support for travel for one person to the site to carry out these initial observations and train in the remote observing procedures. In-person visits for initial observations is required by the Green Bank procedures. Additionally these observations will be very challenging in terms of absolute calibration requirements, and very dry and clear weather requirements.