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Photon Systems in collaboration with JPL are continuing development of a new technology robot-mounted or hand-held sensor for reagentless, short-range, standoff detection and identification of trace levels chemical, biological, and explosive (CBE) materials on surfaces. This deep ultraviolet CBE sensor is the result of ongoing Army STTR and DTRA programs. The evolving 15 lb, 20 W, lantern-size sensor can discriminate CBE from background clutter materials using a fusion of deep UV excited resonance Raman (RR) and laser induced native fluorescence (LINF) emissions collected is less than 1 ms. RR is a method that provides information about molecular bonds, while LINF spectroscopy is a much more sensitive method that provides information regarding the electronic configuration of target molecules. Standoff excitation of suspicious packages, vehicles, persons, and other objects that may contain hazardous materials is accomplished using excitation in the deep UV where there are four main advantages compared to near-UV, visible or near-IR counterparts. 1) Excited between 220 and 250 nm, Raman emission occur within a fluorescence-free region of the spectrum, eliminating obscuration of weak Raman signals by fluorescence from target or surrounding materials. 2) Because Raman and fluorescence occupy separate spectral regions, detection can be done simultaneously, providing a much wider set of information about a target. 3) Rayleigh law and resonance effects increase Raman signal strength and sensitivity of detection. 4) Penetration depth into target in the deep UV is short, providing separation of a target material from its background or substrate.

We present a new active, non-invasive, non-desctructive, in situ spectroscopic method that enable a better understanding of the spatial distribution of microbes, organics, and water on natural surfaces that could support life-detection, organic stability assessment, and in-situ resource utilization missions on planetary bodies. Analytical and spectroscopic methods that have been employed to attempt to address these types of questions provide detection over a limited spatial area, provide either significant false positives/false negatives, or are limited to either morphological or chemical information. Furthermore, apart from the spectroscopic analyses, the methods are limited to invasive treatments that alter the samples or remove critical spatial context. Active spectroscopic methods such Raman and or LIBS have been employed as a means to approach these questions however, traditional Raman scatting is an extremely weak phenomenon and LIBS provides looses information regarding chemical structure. As an alternative, we present the use of deep UV native fluorescence, Raman spectroscopy and hyperspectral imaging from proximity (1-10 cm) to standoff (1-5m). Deep UV native fluorescence, coupled to resonance Raman spectroscopy, can provide a solution that has a means to map large areas with sensitivities to organics, that are expected to be present from meteoritic infall, biosignatures indicating extant or extinct life, and detect the presence of water for in-situ resource utilization. The methodology and the data presented will demonstrate the ability to detect and differentiate organics a natural surface - relevant to Mars and other planetary surfaces, and also elucidate the distribution to enable an understanding of their provenance.

Naphthalene has been identified by the National Research Council as a serious health hazard for personnel working with jet fuels and oil-based sealants containing naphthalene. We are developing a family of miniature, self-contained, direct reading personal exposure monitors (PEMs) to detect, differentiate, quantify, and log naphthalene and other volatile organic compounds (VOCs) in the breathing zone of the wearer or in the hands of an industrial hygienist with limits of detection in the low parts per billion (ppb) range. The VOC Dosimeter (VOCDos) described here is a PEM that provides real-time detection and data logging of exposure as well as accumulated dose, with alarms addressing long term and immediate exposure limits. We will describe the sensor, which employs optical methods with a unique excitation source and rapidly refreshable vapor concentrator. This paper addresses the rapidly increasing awareness of the health risks of inhaling jet fuel vapors by Department of Defense (DOD) personnel engaged in or around jet fueling operations. Naphthalene is a one to three percent component of the 5 billion gallons of jet fuels used annually by DOD. Naphthalene is also a component of many other petroleum products such as asphalt and other oil-based sealants. The DOD is the single largest user of petroleum fuels in the United States (20% of all petroleum fuel used). The VOCDos wearable sensor provides real-time detection and data logging of exposure as well as accumulated dose. We will describe the sensor, which employs endogenous fluorescence from VOCs accumulated on a unique, rapidly refreshable, patent-pending concentrator, excited by a unique deep ultraviolet excitation source.