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Future ProjectsJURASSIC PARK - In MiniatureOctober 5th-9th 2009 Mentors: Benedicta Arhatari, Corey Putkunz, Andrew Peele OverviewX-rays are invisible light waves that have more energy than visible light. We use them to take pictures of our teeth and bones. But did you know that they can be used to take pictures of many other things to understand the structure of objects. X-rays can be used to take pictures of hard materials like metal and also soft materials like biological tissue. Why are they so versatile? X-rays can be high or low energy (like visible light has different colours which represent different energies) and this means that they can be used to visualize (image) the surface or the inside of objects. IntroductionX-raysThe X-rays that penetrate through a very thin objects are low energy and the ones that penetrate through a heavy thick objects are high energy. X-rays can be produced by various instruments such as: X-ray machines, very hot objects in the universe, the synchrotron. X-rays are high energy light given off by very fast moving particles like electrons. X-ray machines have filaments that emit and X-rays. Other machines like the synchrotron has a big circular tube in which electrons are accelerated and at given points around the ring/tube they give off X-rays of various energies, which are used by scientists. The scientists at the synchrotron build end stations at various points around the ring and this is where they harness the x-rays to use in their experiments. Laboratory sources of X-rays such as the X-ray micro-computed tomography machine are very useful but do not produce the bright energy x-rays such as the synchrotron (but it is less expensive to use than the synchrotron). X-rays have a higher energy than visible light but depending on the source producing the X-rays can have relatively high or low energy. High energy x-rays go right through an object like the ones at the dentist and so show regions of high and low density. Low energy x-rays only penetrate a small distance into objects and these can be used to study the surface properties of substances. To use high energy x-rays the synchrotron is needed but it is very expensive and sometimes difficult to set up experiments on the ‘end stations’ at synchrotrons. It is therefore necessary to use more conventional x-ray sources to do experiments to visualize structures. FossilsFossils can be of various types; castes, moulds or mineralisation where all organic content has been replaced by rock, and there can be fossils that may have some organic content remaining such as amber fossils containing insects, small vertebrate animals or plants. Simple photographs can be taken of these animal/plant remains but to cut the amber open would destroy the structure of these fossils and so would be of little value. It is in the structure of the animal and plant remains that palaeontologists learn about the organism and can work out how living things looked, lived and were related to one another. To get information about fossils in amber without destroying the fossil is very important. Having more information about living things in the past helps us to better understand the evolution of life on Earth. Your BriefRecently images of fossil animals in amber have been taken using the synchrotron, but it is very expensive and only a few specimens have been investigated. The project for you to undertake at the CXS group at the Latrobe University, Physics Department is to use an X-ray machine called the X-ray micro-computed tomography machine that is inexpensive to use and easily accessible (compared to the synchrotron) to take images of amber containing insects. To date it is not known whether it is possible to get information about the fossils using this technique. Once the data is collected you will write an article either directed to New Scientist or the LaTrobe University Bulletin (or another forum of your choice). The article will report your findings, and needs to explain the importance and relevance to the community to study investigate science in an integrated way. You will propose further investigations that future groups of students or in fact the scientists can undertake. You will collectively present your week’s investigation to the group of scientists and teachers at the end of the week. Growing Tall Poppies Program: an authentic science experienceYou are the 3rd group to participate in the Growing Tall Poppies Program which is investigating the research being undertaken by the CXS (Coherent X-ray Science Group funded by the Australian Research Council). This center for excellence is approaching science in an interdisciplinary way where Physicists, Biologists and Chemists work together to understand the nature of the world. Please click here to read about the work done by the previous student groups for CXS. Reading materialGood web-sites to read in preparation for your project.
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