SRI | 2011 Research
Simulations of Dark Matter Halo Formation
Christopher Wells, Assistant Professor of Physics, and two students, Colin Lauer and Graeme Little, will be writing and running simulations of dark matter halo formation. It is now known, through indirect observations, that 80% of the mass in our universe is an exotic substance known as ``dark matter.” It is exotic because it cannot be composed of ordinary atoms and dark because it does not produce electromagnetic radiation, i.e. light. Because it does not interact like ordinary matter does, dark matter can more easily aggregate under the influence of gravity in the early universe. These aggregations or ``halos’’ act as a sort of gravitational glue that makes it possible for ordinary matter to populate galaxies and form stars. At present there are nearly a dozen distinct experiments world-wide looking for direct evidence of dark matter, that is the interaction of dark matter with ordinary matter in non-gravitational ways. These experiments and their results rely on knowing where they should be able to find the dark matter and how much momentum it should have on average. Thus, we intend to study the problem of how the dark matter organizes itself in the early universe in a variety of dark matter models. In particular, we want to study models where the dark matter has a variety of self-interactions.
Chemically-mediated Predator-prey Interactions in Larval Black Flies
Aaron Sullivan, Associate Professor of Biology, and two students, Michele Adams and Maya McElfishwill investigate chemically-mediated predator-prey interactions in larval black flies. Our recent field studies show that larvae are more likely to engage in defensive postures when they are exposed to chemical cues from wounded conspecifics and invertebrate predators versus a control stimulus (water). Our approach to the research to be done during the Summer Research Institute of 2011 is to further characterize the responses of larval black flies to cues from vertebrate as well as invertebrate predators and to determine if responses are performed in a threat-sensitive manner. The threat-sensitivity hypothesis essentially states that prey species will respond to a stimulus in proportion to the level of threat perceived as a result of that stimulus. Our research will utilize field techniques to evaluate prey responses to a variety of chemical cues related to predation as well as laboratory studies using an artificial stream apparatus.
Developing an Interferometer for Measuring Stresses in Thin Films
Brandon Hoffman, Assistant Professor of Physics, and two students, Tyler Reynolds and Nicholas Fuller, will design and construct a laser interferometer for measuring stresses in thin metal films. Nanofabricated devices have become extremely important in our ever shrinking world of technology. However, scientists have not yet developed a working model that can explain the properties of the thin films that make up such devices. For instance, thin films can support much higher stresses than their bulk counterparts. These stresses determine the microstructures which, in turn, determine the film’s properties. Most techniques used to resolve stresses in films measure the curvature of a substrate along only one or two axes and calculate the stress from the curvature. Our research group will develop an interferometer that illuminates an entire four inch substrate. Computer software will control the position of the reference mirror and generate a topographical image of the substrate. In this way, stresses can be calculated along any axis in the plane of the substrate.
Development of Green Oxidation Catalysts
Associate Professor of Chemistry, Karen Torraca, will work with two students this summer toward the development of a “green” synthetic method for the conversion of alcohols to ketones or aldehydes. The current standard synthetic process requires large amounts of heavy metals and generates a lot of hazardous environmental waste. Although there is a strong research emphasis across academia to develop better oxidation processes, very few new processes have actually been implemented in large-scale manufacturing due to the lack of robustness. Our ultimate goal will be to develop not only a “green” process, but also one that is amenable to large-scale use where it will have the greatest environmental impact. Our research will focus on the use of palladium catalysts to complete the oxidation of various alcohols to ketones or aldehydes under mild conditions.
Inertial Confinement Fusion
Mark Yuly, professor of physics, and two students, Keith Mann and Andrew Evans, will be working with scientists from SUNY-Geneseo and the Laboratory for Laser Energetics (LLE) in Rochester NY on research related to inertial confinement fusion (ICF). In ICF a large amount of energy is deposited, usually with high-powered lasers, to a small pellet of nuclear fuel in order to initiate a fusion reaction. ICF is currently studied at a number of laboratories around the world – in the United States most notably at the National Ignition Faculty (NIF) and the LLE. In order to characterize the fusion reaction, a system has been developed using activation of 12C. Samples of purified graphite are placed at several locations around the ICF target chamber, where they are exposed to the flux of neutrons produced in the fusion reaction. By far, the biggest remaining obstacle to the implementation of this diagnostic technique is that it depends on accurate knowledge of the 12C(n,2n) cross section, which has not been well-measured. Our primary goal is to develop a technique for measuring this cross section.
Associate Professor of Biology Matt Pelletier worked with two students to attempt to clone a gene encoding a protein believed to be involved in insect development. Efforts to clone and characterize this gene may lead to future discoveries of safe pesticides that could prevent herbivorous insects from destroying crops.
Computer Network Intrusion Detection Systems
Computers and the Internet are an integral part of our daily work and life. As such, computer and computer network security has become increasingly important and relevant. Malicious attacks on computers can cause different damages to organizations and homes, and computer network intrusion detection systems (IDS) are designed to detect such attacks. Most of the intrusion detection techniques developed so far build their detection model offline using the network traffic captured by some specific software, and then deploy the model in real time on the network. There are two limitations of this approach. Firstly, it cannot detect any gradual change of normal behavior, since its model is created offline. Secondly, it is impossible to store the infinite data generated by fast Internet with any finite memory storage to build a model offline. Professor of Math and Computer Science, Wei Hu, and his two students, Zachary Miller and William Deitrick, plan to create a new IDS to tackle both issues. The salient features of their IDS are to update the detection model seamlessly whenever there is a change of normal activities and to maintain the model online all the time with the capacity to process fast Internet traffic.