Does temperature apply to neutrons and subatomic particles?

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coolul007
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Does temperature apply to subatomic particles, in particular the neutron? The question is prompted by the definition of absolute zero, being specific to atomic movement.
 
coolul007 said:
Does temperature apply to subatomic particles, in particular the neutron?
I am not sure if a get question properly but, in general, particles temperature can be defined with its kinetic energy
slow neutrons are colder, hot neutrons are faster..

as analogue of classical temperature, where $$ T \sim <E_k> $$
 
coolul007 said:
Does temperature apply to subatomic particles, in particular the neutron? The question is prompted by the definition of absolute zero, being specific to atomic movement.

I don't think you understand the definition of temperature. It is a measure of the average kinetic energy of an ensemble of ANY particles, neutrons included.

If you do a search, you can even find, especially in a solid state text or webpage, the temperature of the "electron gas" in a conductor at room temperature.

Zz.
 
Yes neutrons have a temperature. For non-relativistic free neutrons (eg: moderated neutrons radiating from a nuclear reactor) the equations are trivial ##E = \frac{3}{2}k_{B}T## where ##E## is the kinetic energy ##E = \frac{1}{2}mv^{2}##. Indeed, at neutron scattering facilities dedicated to using neutrons as a probe of condensed matter, the different instruments are typically classified as cold, thermal, or hot. Which is a direct reference to the neutron temperatures used in the scattering experiments.
 
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I was thinking of temperature in the classic sense of atom versus subatomic particle. I have been lied to about atoms my whole life, so if I am way off base here I apologize. My understanding is the atoms increase "temperature" by absorbing photons. Therefore a rock that does not have kinetic energy can have "stored heat". Therefore, my thoughts went to particles that don't seem to absorb a photon and are at "rest" in the nucleus of an atom. That is what spurred my question.
 
coolul007 said:
I have been lied to
That's a bit harsh. I probably got the same stories but don't share the feeling; learning is a gradual process that has to start somewhere. And what you can absorb in one step is limited (as well as what you can absorb in a whole lifetime :cry: :confused: ).
 
coolul007 said:
My understanding is the atoms increase "temperature" by absorbing photons.
I wouldn't say that is a meaningful statement. It's trying to extend a macroscopic, statistical idea into the behaviour of a single entity. Absorbing Energy doesn't imply a pro-rata increase in temperature, even in a real gas because input energy can result in an increase in Potential Energy as well as KE. Van der Vaal forces beween gas molecules stop them behaving ideally.
I would say that you haven't been "lied to" as much as taken an inappropriate message from a not-to-good presentation of the situation.
 
BvU said:
That's a bit harsh. I probably got the same stories but don't share the feeling; learning is a gradual process that has to start somewhere. And what you can absorb in one step is limited (as well as what you can absorb in a whole lifetime :cry: :confused: ).
I didn't mean to be harsh, the implication is that, as understanding increases the previous teachings are invalidated. I'm 72 1/2 years old, so you can imagine the world, as well as the subatomic world has changed for me. I ask this question in relation to absolute zero, being the lack of "static" energy in an atom. I was just pondering if there is a subatomic equivalence. No condemnation of physicists on my part. Thank you for your replies.
 
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coolul007 said:
I didn't mean to be harsh, the implication is that, as understanding increases the previous teachings are invalidated. I'm 72 1/2 years old, so you can imagine the world, as well as the subatomic world has changed for me. I ask this question in relation to absolute zero, being the lack of "static" energy in an atom. I was just pondering if there is a subatomic equivalence. No condemnation of physicists on my part. Thank you for your replies.
I think you're asking if neutrons have "internal" temperature as well as "external" temperature that SpinFlop described. Atoms can receive energy which pushes electrons into "higher orbits". I don't believe there is an equivalent in neutrons.