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Pair production is the transformation of electromagnetic energy into matter, into a particle and its antiparticle, usually an electron and a positron. Let's have a look at this situation.
When a high energy gamma ray with a minimum energy of 1.022 MeV passes close to an atomic nucleus, a phenomenon called pair production can occur. In this event, the energy of the gamma ray is converted into mass. It's a play right out of Albert Einstein's quantum mechanical playbook. The electron and positron are opposites of each other, and the appearance of an elementary particle and its antiparticle must obey conservation laws. That's where the "assistance" of a nearby atomic nucleus comes in. The electron and positron will appear and come away from the event with some given kinetic energy, and will scatter and slow down as they move off. The positron, of course, will end up combining with an electron in a mutual annihilation event where the two particles have their mass entirely converted into energy. This will result in a pair of electromagnetic rays, or photons, leaving the annihilation event and moving in opposite directions.
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Can pair production take place in a vacuum?
== No. In a complete vacuum with nothing there, electromagnetic energy (the gamma ray from which pair production might arise) will proceed unaffected and at the speed of light. The question asks specifically about a vacuum and suggests that there is nothing there to in any way react with the gamma ray. So the answer is that pair production will not take place in, say, the extreme vacuum of deep space where a gamma ray is passing. If we start "tinkering" with the scenario and, say, firing high energy gamma rays down an evacuated pipe through which we pass a magnetic field, pair production might then occur. But it is impossible to have a magnetic field without having the material to create it - moving charges. No moving charges, no magnetic field, no pair production. Pair production will not arise spontaneously from a gamma ray of sufficient energy to facilitate it, and this is almost certainly what the question is asking. Additional information There has been publication of research that suggests that a magnetic field can initiate pair production, but the investigation continues, and the idea of doing this "strays" from what is arguably the true intent of the question. It would have been easy to change the question, but why not leave up what is up? The idea that a magnetic field can initiate pair production is an interesting one.
What is the effect of gamma rays on living tissue?
Compton Scattering, Photoelectric Effect, and Pair Production.
What happens if the energy of a photon exceeds that necessary for pair production?
The excess energy is transferred to the particles as kinetic energy.
How momentum is conserved in pair production before and after collision?
That means that total momentum doesn't change. It is the same before and after the collision.
Write down the three distinct way by which gamma radiations interact with matter?
Photoelectric Effect, Compton Effect, and Pair Production.
Can pair production produce in vacuum?
pair production can not produce in vaccum
What three types of primary industries are involved in the production of a pair of skates?
What three types of manufacturing industries are involved in the production of a pair of skates
Is Pair Production possible near black hole?
Yes. The (as yet hypothetical) Hawking radiation is due to pair production near the border (event horizon) of a black hole.Yes. The (as yet hypothetical) Hawking radiation is due to pair production near the border (event horizon) of a black hole.Yes. The (as yet hypothetical) Hawking radiation is due to pair production near the border (event horizon) of a black hole.Yes. The (as yet hypothetical) Hawking radiation is due to pair production near the border (event horizon) of a black hole.
What primary economic activities are associated with making a pair of jeans?
Cotton production, dye production, and metal production (for the buttons and rivets).
What are the best pair of headphones for studio production?
Beats by DR. DRE
What three manufacturing industries are involved in the production of a pair of skates?
hi
What is the effects of gamma on living tissues?
Compton Scattering, Photoelectric Effect, and Pair Production.
What are the pair of ligaments covered by laryngeal epithelium that function in sound production?
vocal cords
Can pair production take place in a vacuum?
== No. In a complete vacuum with nothing there, electromagnetic energy (the gamma ray from which pair production might arise) will proceed unaffected and at the speed of light. The question asks specifically about a vacuum and suggests that there is nothing there to in any way react with the gamma ray. So the answer is that pair production will not take place in, say, the extreme vacuum of deep space where a gamma ray is passing. If we start "tinkering" with the scenario and, say, firing high energy gamma rays down an evacuated pipe through which we pass a magnetic field, pair production might then occur. But it is impossible to have a magnetic field without having the material to create it - moving charges. No moving charges, no magnetic field, no pair production. Pair production will not arise spontaneously from a gamma ray of sufficient energy to facilitate it, and this is almost certainly what the question is asking. Additional information There has been publication of research that suggests that a magnetic field can initiate pair production, but the investigation continues, and the idea of doing this "strays" from what is arguably the true intent of the question. It would have been easy to change the question, but why not leave up what is up? The idea that a magnetic field can initiate pair production is an interesting one.
What is the effect of gamma rays on living tissue?
Compton Scattering, Photoelectric Effect, and Pair Production.
What happens if the energy of a photon exceeds that necessary for pair production?
The excess energy is transferred to the particles as kinetic energy.
What is the minimum energy to produce ionization?
The minium required energy of a photon that is involved in the creation of an electron-positron pair (which is pair production), is 1.022 MeV.An electron-positron pair has a given probability of being produced when a photon of the stated energy (or a higher energy) passes close the nucleus of an atom. Pair production does not happen "in the presence of a photon" but happens as a direct result of the the actual presence of a photon (having at least the stated energy) in the presence of an atomic nucleus. The presence of an atomic nucleus is necessary to insure conservation of the quantum mechanical characteristics of the event. Said another way, the high energy photon alone cannot spontaneously create the electron-positron pair in pair production. A link can be found below to related questions.
