Shaul Hanany - US grants

This project is for the development of two technologies: (1) a magnetic bearing; and (2) broad-band, cryogenic, anti-reflection coatings, both of which could be useful for high sensitivity measurements of the polarization of the cosmic microwave background radiation. The technology will be applicable to a broad range of astrophysical measurements, and the technology development will involve the education of graduate students in advanced instrumentation techniques.

The proposal seeks funding to begin a research effort on characterizing and extracting galactic dust emissions from the data that will be collected by the NASA-funded Antarctic Long Duration Balloon-borne (LDB) ?E and B Experiment? (EBEX). A leading cosmological paradigm for the beginning and evolution of the Universe posits a period of Inflation shortly after the Big Bang. Inflation generated primordial gravitational waves in the Universe that imprinted a distinct signature called the "B-mode signal" on the polarization of the Cosmic Microwave Background (CMB) radiation. This signal is extremely weak, around 100 microKelvins or smaller, and astrophysical foregrounds such as polarized emission from galactic dust and synchrotron radiation swamp the Inflationary signal over most of the sky. The EBEX balloon payload will have the sensitivity to detect the B-mode signal if it is stronger than 1/10 of the current theoretical upper limit. The balloon observations will be carried out in frequency bands between 150 and 410 GHz. The higher end of this band is not accessible from the ground; thus, EBEX can provide valuable information on the properties of galactic dust emissions. This information is critical for all the CMB experiments searching for the Inflationary signal. EBEX is currently awaiting its flight from Antarctica in the austral summer of 2010/2011. The requested funds will be used to support a post-doctoral fellow and a graduate student to work on the characterization and extraction of galactic dust foregrounds from the EBEX data.

The investigators will improve the performance of telescopes that study the large scale properties of the early Universe. For best performance such telescopes utilize optics made from alumina, sapphire, and silicon. The investigators seek to develop a new technique to modify the surfaces of such optics to increase the amount of light that can be utilized. The techniques developed will also allow the optics to operate over a larger range of temperatures. Such improvements will enable astronomers to collect light more efficiently and collect better scientific observations. . Successful development will lead to a technique that can then be industrialized on large scales.<br/>This work will involve the efforts of graduate student. An expansion of an outreach program that reaches tens of thousands of school-age kids and families annually is also planned.<br/><br/>The search by cosmic microwave background (CMB) instruments to find the signatures of inflation, constrain the sum of neutrino masses, and trace the formation of cosmic structures requires ever larger throughput from the optical systems utilized. In response, optical designers are increasingly using optical elements made of alumina, silicon, and sapphire for higher throughput. This project aims to develop broad-band, cryogenically-robust, anti-reflection coating (ARC) for optical elements made of alumina, sapphire, and silicon using laser ablation of sub-wavelength structures (SWS). Maturing this technology will solve a technology bottleneck in millimeter and sub-millimeter astrophysics for CMB instruments. This resulting scalable and reproducible ARC fabrication approach, will be transferred to industrial partners. This will permit researchers to have purchasable, turn-key solutions for their ARC needs instead of solving the challenge anew with every project. The project looks to develop a prescription for the processing steps need to manufacture such ARCs that can be transferred to corporate entities.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.