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How X-rays Work" X-rays are basically the same thing as visible light rays. Both are wavelike forms of electromagnetic energy carried by particles called photons (see How Light Works for details). The difference between X-rays and visible light rays is the energy level of the individual photons. This is also expressed as the wavelength of the rays. Ablation. Ablation is removal of material from the surface of an object by vaporization, chipping, or other erosive processes.

Examples of ablative materials are described below, and include spacecraft material for ascent and atmospheric reentry, ice and snow in glaciology, biological tissues in medicine, and passive fire protection materials. Ablation near the electrode in a flashtube. Nuclear Fission Basics. The debate over nuclear power plants has been going on for some time, with nuclear physicists and lawmakers alike throwing around terms like nuclear fission, critical mass, and chain reaction.

But how does nuclear fission work, exactly? In the 1930s, scientists discovered that some nuclear reactions can be initiated and controlled. How does fission work? Ryan, It's not so much the kinetic energy of the neutron - but the fact that it is falling into a nuclear potential well. Imagine you had an old well - the type people used to haul water up from in a bucket.

Except this well is dry - it's just a very deep hole in the ground lined with stones. How do nuclear fusion and nuclear fission work. Compton Scattering. In Compton scattering, an incoming photon of energy E (shown in black) undergoes an elastic collision with a weakly bound (assumed free) outer-shell electron (shown in blue).

Compton Scattering

The electron is scattered with kinetic energy K at an angle j with respect to the x-axis (direction of incoming photon) while the scattered photon of energy E' (shown in green) makes an angle q with respect to the x-axis. Because energy has been given to the scattered electron, the scattered photon will have a lower energy and therefore a longer wavelength than the incident photon. Electrons, photons, and the photo-electric effect. We're now starting to talk about quantum mechanics, the physics of the very small.

Electrons, photons, and the photo-electric effect

Planck's constant At the end of the 19th century one of the most intriguing puzzles in physics involved the spectrum of radiation emitted by a hot object. Specifically, the emitter was assumed to be a blackbody, a perfect radiator. The hotter a blackbody is, the more the peak in the spectrum of emitted radiation shifts to shorter wavelength. Nobody could explain why there was a peak in the distribution at all, however; the theory at the time predicted that for a blackbody, the intensity of radiation just kept increasing as the wavelength decreased. Plasmas. Plasmas exist in a wide range of settings and varieties.


Most stars are made up of plasma. The Aurora Borealis is a plasma light show in our upper atmosphere caused by the bombardment from space of the solar wind - another kind of plasma. Lightning bolts are visible plasma trails left by the passage of the electric current that formed it. As stated in the definition, plasma is a gaseous type of state where the matter making the plasma consists of electrically neutral and charged particles. Overall, plasma is electrically neutral having as many positive ions as free electrons distributed through it. New Cold Fusion Evidence Reignites Hot Debate. 25 March 2009—On Monday, scientists at the American Chemical Society (ACS) meeting in Salt Lake City announced a series of experimental results that they argue confirms controversial ”cold fusion” claims.

New Cold Fusion Evidence Reignites Hot Debate

Chief among the findings was new evidence presented by U.S. Navy researchers of high-energy neutrons in a now-standard cold fusion experimental setup—electrodes connected to a power source, immersed in a solution containing both palladium and ”heavy water.” National Ignition Facility. The National Ignition Facility, located at Lawrence Livermore National Laboratory.

National Ignition Facility

The target assembly for NIF's first integrated ignition experiment is mounted in the cryogenic target positioning system, or cryoTARPOS. The two triangle-shaped arms form a shroud around the cold target to protect it until they open five seconds before a shot. National Ignition Facility & Photon Science - Bringing Star Power to Earth. Scientists plan to ignite tiny man-made star. How scientists brought the power of the Sun to Earth « Goodheart's Extreme Science. How scientists brought the power of the Sun to Earth Posted by Steven Goodheart on February 1, 2010 · 6 Comments The super-amplified light impacts the target area with an intensity and ferocity only found in the hottest places in the universe.

How scientists brought the power of the Sun to Earth « Goodheart's Extreme Science

Imagine 500 times the energy of the entire United States being used at any given moment focused on a target smaller than a pinhead! Fusion power. The Sun is a natural fusion reactor.

Fusion power

Fusion power is the energy generated by nuclear fusion processes. In fusion reactions, two light atomic nuclei fuse to form a heavier nucleus (in contrast with fission power). 106, 085004 (2011): Demonstration of Ignition Radiation Temperatures in Indirect-Drive Inertial Confinement Fusion Hohlraums. Big science in a small space. The National Ignition Facility (NIF) at Lawrence Livermore in California was designed with a specific goal: to use high-powered lasers to ignite a fusion reaction that releases more energy than the one million joules needed to start it.

Big science in a small space

Now, in a pair of papers appearing in Physical Review Letters (Kline et al. and Glenzer et al.), scientists at NIF are reporting some of the first tests at the new facility. In experiments that simulate “real” conditions more closely than any previous attempt, the team shows they are able to successfully generate the almost sunlike levels of heat needed for laser-driven fusion. The planned target of NIF’s lasers is a pill-sized hollow gold target, called a hohlraum, that encases a “fusion capsule”—about micrograms of solid deuterium-tritium mix, surrounded by a light material.

Nuclear Fusion : WNA. (Updated February 2014) Fusion power offers the prospect of an almost inexhaustible source of energy for future generations, but it also presents so far insurmountable scientific and engineering challenges.

Nuclear Fusion : WNA

The main hope is centred on tokamak reactors which confine a deuterium-tritium plasma magnetically. Today, many countries take part in fusion research to some extent, led by the European Union, the USA, Russia and Japan, with vigorous programs also underway in China, Brazil, Canada, and Korea. Initially, fusion research in the USA and USSR was linked to atomic weapons development, and it remained classified until the 1958 Atoms for Peace conference in Geneva.