SBIR-STTR Award

The physical phenomena that dominates the use of submillimeter (SMM) spectra for the analysis of missile intercepts is the rapid cooling of the post-intercept gas and debris field and its impact on the SMM spectral signatures and post-impact chemistry. It is likely that the initial high temperatures and density will result in a molecular soup that is much more complex than the atomic mixtures that provide the short time emission spectra. With this complexity and richness of spectra come the prospects of much more signature specificity, as well as additional information about the physical states of the expanding gas cloud. An important aspect of the proposed Phase 1 effort will be to determine if enough information exists or can be developed for the envisioned Phase 2 code development. If not, we will provide alternative paths forward toward that end. These will emphasize the use of general principles of spectroscopy, chemistry, and remote sensing to establish those points in the evolution of the expanding gas and debris fields that are most likely to provide useful signatures so that resources can be focused on developing the required chemical, spectroscopic, and physical information.

Keywords:
Molecular Rotational Spectroscopy, Signatures, Submillimeter Wave Spectroscopy, Terahertz Spectroscopy

Our Phase I study provided quantitative results that showed feasibility for scenarios of interest. It included both the details of signatures and the sensitivity for THz sensor systems with realistic parameters. In Phase II we will extend these results to create a non-scenario specific model that will serve as an interface with the intercept community allowing the capabilities of the THz to be optimized for kill assessment. Key elements of the model will include appropriate description of the temperatures of the several degrees of freedom for both the gas and the debris; chemical and physical models for the expanding cloud; pressure broadening, doppler broadening, and collisional processes: more detailed modeling of the debris cross-sections. In addition, we expect to acquire currently unavailable Thz signature measurements, which with the model effort, will guide the system design for Thz signature detection. The work plan includes the following elements: Develop a model for THz signature generation; Generation of THz spectral signature data; Provide system design for THz signature detection; Assemble a sparse signal THz detection module; Integrate THz results with MDA code contractor(s).

Keywords:
Molecular Rotational Spectroscopy, Signatures, Submillimeter Wave Spectroscopy, Terahertz Spectroscopy