This article is a report submitted as part of a class at Stanford University and is intended to educate the general public about particle accelerators. Particle accelerators, as the name suggests, are devices used to energize or accelerate subatomic particles to high levels of energy and speed.  These high speed particles are then used for various purposes which typically include investigations into nuclear physics and the subatomic structure of matter.  Two well-known examples of particle accelerators that are used today are the Large Hadron Collider built by CERN and the Stanford Linear Accelerator Center (SLAC) operated by Stanford University. Advanced research carried out at such centers has found wide application and provides a means to satisfy manâ's unending curiosity.  Such efforts have even found their way into works of fiction like Dan Brown's best-seller Angels and Demons and are often discussed in popular television programs like The Big Bang Theory.
Based on the method used to accelerate particles, accelerators can be divided into two main categories: Linear Accelerators and Circular Accelerators. Linear Accelerators consist of linearly arranged accelerating units. These units are so arranged that particles gain energy through each stage. Particles are generally fed into one end of the unit and are consumed for research at another end. In order to achieve high particle beam energies, linear accelerators have to be very long and thus become costly.  Circular Accelerators are those in which the particles to be accelerated are passed through the accelerating units in a repeated or circular manner. This enables them to acquire energy on each pass. An example of a circular accelerator is the cyclotron. Some devices like the synchrotron use a combination of these two methods of acceleration. 
There are important research applications of particle accelerators. A significant goal of particle accelerator research is towards studying the structure of particles. Researchers have often been able to produce particles that were previously unknown or unobserved.  Other research endeavors include the fields of biology, medicine, and surface chemistry
It is believed that accelerators will prove to be invaluable research tools to aid technological progress. A significant step to advance research in this area was taken when a large international community of scientists produced the basic design for the International Linear Collider (ILC).  The author believes that particle accelerators may hold the key to understanding the world around us and our universe.
© Calvin Dsouza. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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