Number of quantum accessible states of a particle given T, N?

damarkk
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Homework Statement
How to find a number of accessible quantum states of a gas particle with spin S and given T, N (number of particles of the system)?
Relevant Equations
Boson gas, Fermion gas
It's given a gas of particles all identical which has T fixed and spin S. Let's ##g(\epsilon)## the density of orbital states and

##g(\epsilon) = g_0## for ##\forall \epsilon \in [\epsilon_0, \epsilon_1]##, zero otherwise.

How to compute the number of accessible quantum states of one particle?


This is my attempt, and I suspect that is not good. Let S=0 and then bosons in a system.

Simply, if we have the density of orbitals we have to integrate ##g(\epsilon)## and we have ##\int_{\epsilon_0}^{\epsilon_1} g(\epsilon) d\epsilon## and we get that is ##g_0(\epsilon_1-\epsilon_0)##.
 
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It seems that we have N particles with spin S in contact with a heat bath at temperature T. OK.
That is enough to specify the number of accessible states as (2S+1). Setting the spin equal to zero would result in one state only.
In the absence of a perturbation, e.g. an external magnetic field, the (2S+1) states are degenerate which makes them equally accessible at any temperature.
Also, I do not understand the bit about orbital states. Whence orbital states? Presumably the particles are free.

Can you give us the original statement /question as you were given, damarkk?

Attn @kuruman
 
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