An alpha particle is deflected by a magnetic field
Alpha particles or alpha rays are a form of particle radiation which are highly ionizing and have low penetration. They consist of two protons and two neutrons bound together into a particle that is identical to a helium nucleus, and can be written as He2+.
Alpha rays are easily absorbed by materials and can travel only a few centimeters in air. They can be absorbed by tissue paper or the outer layers of human skin and so are not generally dangerous to life unless the source is ingested or inhaled. If alpha radiation does enter the body, however, it is the most dangerous form of ionizingradiation. They are the most strongly ionizing, and with large enough doses can cause any or all of the symptoms of radiation poisoning.
Most smoke detectors contain a small amount of the alpha emitter americium-241. This isotope is extremely dangerous if inhaled or ingested, but the danger is minimal if the source is kept sealed.
Because alpha particles occur naturally, but can have energy high enough to participate in a nuclear reaction, study of them led to much early knowledge of nuclear physics.
In computer technology, DRAM 'soft' errors were linked to alpha particles in 1978 in Intel's DRAM chips. The discovery has led to strict control of radioactive elements in the packaging and semiconductor materials, and the problem was largely considered 'solved'.
Alphaparticles or alpha rays (named after the first letter in the greek alphabet, α) are a highly ionizing form of particle radiation which have low penetration.
When an alphaparticle is emitted, the atomic mass of an element goes down by roughly 4 amu, due to the loss of 4 nucleons.
The physicist Ernest Rutherford famously used alphaparticles to infer that Lord Kelvin's "plum pudding" model of the atom was fundamentally flawed.
In alpha decay, the atomic number changes, so the original (or parent) atoms and the decay-product (or daughter) atoms are different elements and therefore have different chemical properties.
In the alpha decay of a nucleus, the change in binding energy appears as the kinetic energy of the alphaparticle and the daughter nucleus.
Because this energy must be shared between these two particles, and because the alphaparticle and daughter nucleus must have equal and opposite momenta, the emitted alphaparticle and recoiling nucleus will each have a well-defined energy after the decay.
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