Nuclear fusion is quite a way off becoming viable although progress is being made with larger and larger fusion reactors being created all the time. So far the largest reactor that is being built at the moment, ITER, will have an exhaust power of about 150 megaWatt. When a proper fusion power plant is created it would have an exhaust power of about 800 megaWatt. A divertor is a component of a fusion reactor which uses a magnetic field to define a plasma boundary. The divertor can be controlled to manage and shape the plasma into a D-shape plasma (a more elongated ovular form). In this state, the heavy ions, which are the main component of the “exhaust” of the fusion, are flung out and separated with greater ease. Unfortunately the current limit of divertors are 10 megaWatt per metre squared and it doesn’t seem this limit is set to increase. Radiative cooling has to be employed in future reactors if they can’t provide the exhaust space for the current divertor ability.
There is condensed matter physics, where particles have to adhere to eachother (hence the word condensed). There’s plasma physics, where electrons have stripped from all the atoms leaving just a gas of ions behind. There is also an intermediate step. This is where the temperature is such that the average kinetic energy of the electrons is about equal to the binding potential energy that holds them to the nuclei. This means it is too cold for condensed matter physics where its a guarantee that the electrons will be liberated, but too hot for condensed matter physics where the electrons are guaranteed to be bound. This is called warm dense matter and is not easily modelled by either branch of physics.
The importance of the Sun in our solar system cannot be overstated. When considered, it is quickly realised that almost all sources of energy on this planet come from the Sun. For solar power it is obvious, but wind power is caused by the temperature gradient the Sun produces and fossil fuels originally started out as plants absorbing energy through photosynthesis. The two main exceptions are tidal power, which is a conversion of the Earth and Moon’s rotational kinetic energy and geothermal power, which is gained from nuclear decay in the Earth’s core.
Ultra high energy cosmic ray (UHECR) are cosmic rays which are measured to have over 1018 eV of kinetic energy. Many of these particles exist beyond the Greisen–Zatsepin–Kuzmin limit, a theoretical limit based on the interaction of the cosmic rays above a certain energy threshold and the photons of the cosmic microwave background radiation. In essence if the particles were of too high energy they would of interacted and slowed down, but this restriction only applies over a certain distance. UHECRs are believed to be produced locally and so are not restricted by the limit. There is also a possibility that heavier nuclei my circumvent the limit also but what particles make up UHECRs are still unknown. Despite this the mass compositions have been measured by the Pierre Auger Observatory in Argentina which is believed to show particles of higher mass than helium with an upper limit of about iron.
The discovery of nuclear magnetic resonance is described as one of the great scientific achievements of the last century. It was found that any atom with an odd number of nucleons in the nucleus would exhibit a magnetic moment. Luckily common isotopes such as hydrogen-1, carbon-13, fluorine-19, and phosphorous-31 exist which can be easily analysed (technically hydrogen-2 and nitrogen-14 also have magnetic moments but there are difficulties present in these cases). When anything with a magnetic moment is placed in a magnetic field it will experience a torque which rotates it, for objects the size of nuclei the magnetic field needs to be great, many Tesla normally.
I would hope that every body reading would at least have some idea of what a solar flare is. When eruption on the Sun are great enough it is possible for a coronal mass ejection to occur. This massive release of plasma (weighing up to 100,000,000,000 kg, and considering it’s gas that’s an incredible volume) and magnetic flux which speed away from the Sun at about 1500 km s−1. They can be considered as one of the driving forces for space weather and are also important for understanding the Sun’s magnetic field in the corona. Now at the surface of the Sun, where the magnetic fields permeate, they end up bending back and reconnecting at constantly shifting points. This massive three dimensional structure is known as the magnetic flux ropes.
Some elements are incredibly common and have been studied for hundred of years in one form or another. Abundant elements like oxygen, nitrogen and hydrogen are easy to find as they are literally all around us. Other elements like gold, lead and copper are unreactive and so are easily found lying around most of the time in their elements form or in an easily extractable ore. Elements near the bottom of the periodic table, in the radioactive set, are not only rare as they are constantly decaying but also are quite reactive. The example under examination today is one that most people will have heard of as it is that of plutonium. Samples of plutonium have over recent years been subject to a series of experiments and associated theoretical treatment from X-ray spectroscopy to neutron scattering.