Innovative Multiband Filters

用于天文成像的滤光器通常或多或少地均匀地接纳两个波长极值之间的所有光。然而，存在高度期望更复杂的传输函数的情况。 其中一种情况是在近红外，其中地球大气中的分子OH的发射发生在窄带。 在这里，如果分子谱线可以被选择性地阻挡，则用宽带滤波器成像的背景可以减少两倍。 直到最近，过滤器的自定义“调谐”是不可能的。 然而，它现在不仅实用，而且是一种提高近红外探测速度的引人注目的技术。 与其他提高效率的方法相比，有充分的理由相信，这种创新的成像滤光器也应该是廉价的。亚利桑那州立大学的James Rhoads博士建议进行定制红外成像滤光器的开发，与商业供应商合作，为天文学中的各种应用进行设计和表征。 将看到质量效益的研究领域包括：a）寻找最早的星系和类星体，B）发现高红移超新星和表征暗能量，以及c）通过开发一种特殊的过滤器来识别质量最低的褐矮星，该过滤器调整到其独特的近红外光谱。PI将监督这些滤光片的设计、建造和评估，并提供功能光学器件，供公众在国家光学天文台的仪器上使用。 此外，将公布滤波器规定，供整个观测天文学界复制。 这项工作的资金由NSF的天文科学部通过其先进技术和仪器计划提供。

Filters for astronomical imaging have typically admitted more or less uniformly all of the light between two wavelength extremes. However, there are instances where more complex transmission functions are highly desirable. One such case is in the near-infrared, where terrestrial atmospheric emission arising from the molecule OH occurs in narrow bands. Here, the background for imaging with a broadband filter could be reduced by a factor of two if the molecular lines could be selectively blocked. Until recently, custom "tuning" of filters was not possible. However, it is now not only practical but also a compelling technique for improving the speed of near-IR surveys. Compared to other methods of enhancing efficiency, there is every reason to believe that such innovative imaging filters should also be inexpensive.Dr. James Rhoads of the Arizona State University proposes to carry out the development of custom infrared imaging filters, working with commercial vendors in their design and characterization for a variety of applications in astronomy. Among the research areas that will see a qualitative benefit are a) finding the earliest galaxies and quasars, b) discovering high-redshift supernovae and characterizing dark energy, and c) identifying the lowest-mass brown dwarfs through the development of a special filter tuned to its unique near-IR spectrum. The PI will oversee the design, construction, and evaluation of these filters, and in addition provide functioning optics for use by the public on instruments operated at the National Optical Astronomy Observatories. Furthermore, the filter prescriptions will be publicized for duplication by the entire observational astronomy community. Funding for this work is being provided by NSF's Division of Astronomical Sciences through its Advanced Technologies and Instrumentation program.