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Old Jul 25th 2017, 08:30 AM   #1
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Neutrino and conservation of energy.

In the process of beta decay the neutrino carries the missing energy and also in this process the law of conservation of energy remains valid.

In beta decay, a neutron in an unstable nucleus transforms into a proton and emits an electron or a proton transforms into a neutron and emits a positron at the same time.

When a radioactive nucleus emits a beta particle (electron), the electron may have any energy from zero up to a certain maximum. Pauli suggested that when the electron has less than the maximum possible value, the remaining energy is carried away by an undetected particle, the neutrino. If this is not so then the law of conservation of energy would be violated.

Is this correct?
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Old Jul 25th 2017, 09:02 AM   #2
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Conservation of mass.

We know that the mass of an electron plus the mass of a proton is less than mass of a neutron. When a neutron decays into a proton and electron (beta process) mass is conserved because the remaining mass is in the form of a neutrino and it is energy. Neutrino is energy.

Does it also mean that missing mass may be converted to photons instead of neutrino?
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Old Jul 25th 2017, 01:22 PM   #3
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Originally Posted by avito009 View Post
When a radioactive nucleus emits a beta particle (electron), the electron may have any energy from zero up to a certain maximum. ...

Is this correct?
Just to be a fly in the ointment...

How can an emitted particle have zero energy? If it has zero energy it won't move.
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Old Jul 25th 2017, 01:40 PM   #4
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Originally Posted by kiwiheretic View Post
Just to be a fly in the ointment...

How can an emitted particle have zero energy? If it has zero energy it won't move.
He either is speaking about kinetic energy or doesn't know about mass energy.
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Old Jul 25th 2017, 11:04 PM   #5
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Mass Energy definition.

The mass of a body regarded relativistically as energy.
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Old Jul 25th 2017, 11:17 PM   #6
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Clarification

Originally Posted by Pmb View Post
He either is speaking about kinetic energy or doesn't know about mass energy.
Yes I was speaking about kinetic energy. From wikipedia:

Beta particles can therefore be emitted with any kinetic energy ranging from 0 to Q. A typical Q is around 1 MeV, but can range from a few keV to a few tens of MeV.
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Old Jul 26th 2017, 04:01 PM   #7
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Originally Posted by avito009 View Post
Neutrino is energy.
Not true. Neutrinos, like any other particle, have certain properties: They are electrically neutral, massless (at least theoretically), carry weak hypercharge, are "left handed," and carry momentum, and energy. There is no such thing as "pure energy."

-Dan
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Old Jul 29th 2017, 10:53 AM   #8
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Originally Posted by topsquark View Post
Not true. Neutrinos, like any other particle, have certain properties: They are electrically neutral, massless (at least theoretically), carry weak hypercharge, are "left handed," and carry momentum, and energy. There is no such thing as "pure energy."

-Dan
Dan. Neutrinos were actually found to have mass. This has been the revelation in particle physics for some time now. It has to do with neutrino oscillation.

See: https://en.wikipedia.org/wiki/Neutrino
The Nobel prize in Physics 2015 was awarded to both Takaaki Kajita and Arthur B. McDonald for their experimental discovery of neutrino oscillations, which demonstrates that neutrinos have mass
See also: https://en.wikipedia.org/wiki/Neutrino_oscillation


As far as pure energy, whomever believes that please see:
http://www.newenglandphysics.org/com...an_Guth_02.mp4
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Old Jul 29th 2017, 10:54 AM   #9
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Originally Posted by topsquark View Post
Not true. Neutrinos, like any other particle, have certain properties: They are electrically neutral, massless (at least theoretically), carry weak hypercharge, are "left handed," and carry momentum, and energy. There is no such thing as "pure energy."

-Dan
Dan - I sent you several PMs. Did you get them and read them?
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