Re: Temperature applied to small group of particles

[Ludwik Kowalski <kowalskil@MAIL.MONTCLAIR.EDU>]

And the concept "nuclear temperature" has been used to describe excited
atomic nuclei (which then emit neutrons, protons, etc.). Some of the
systems contain no more than 20 particles. Temperature here is a
useful, operationally defined, parameter. It can be "measured" by
analyzing energy spectra of emitted neutrons, protons or alpha
particles.
Ludwik Kowalski

On Tuesday, March 9, 2004, at 08:19 AM, Brian Whatcott wrote:

> People who trap a few particles in a laser beam are pleased
> to talk about refrigerating them to low, low temps.
> (By discarding particles with discernable doppler effect)
>
> Brian W
>
> At 06:18 AM 3/9/2004, you wrote:
> > Is the term temperature of a system of say, 50 particles meaningful?
> > If
> > not What macroscopic(?) state variable would be most appropiate to
> > define
> > the energy of the system?  Intuatively I don't think you can define
> > temp
> > here as there are not enough particles to give a statistically
> > accurate
> > measure of the speed.  By this I mean that the velocity of a
> > particular
> > particle  could easily be far away from the mean speed and hence skew
> > the
> > results.  Infact maybe the mean speed is not even appropiate in this
> > system...maybe modal is bettter.
> >
> > Can I get any measure of the energy of the system?
> >
> > Thanks
> > for any ideas.
> >
> > Alex
>
>
> Brian Whatcott    Altus OK    Eureka!