Re: [Phys-L] neutrons

[Brian Whatcott <betwys1@sbcglobal.net>]

 In the case of detecting proton spin precession of water, it is desirable to provide 120 dB  plus of voltage gain with low noise contribution. I hardly think that neutron spin relaxation is any less demanding.  Accordingly I expect diode detection of the alternating signal is unlikely to succeed.

[b c] Since I’m an experimentalist, not theory, I thought I’d  attach a bar magnet to a vibrator (I have a powerful one for preparing [registering?] paper for binding) and use a loop antenna, diode, and my Keithley.  However, I think the second part of this

http://www.physics.sfsu.edu/~lea/courses/ugrad/460notes5.PDF ;<http://www.physics.sfsu.edu/~lea/courses/ugrad/460notes5.PDF>  does all. 

    On Tuesday, February 9, 2021, 11:59:48 PM CST, bernard cleyet <bernard@cleyet.org> wrote:  
 
 Since I’m an experimentalist, not theory, I thought I’d  attach a bar magnet to a vibrator (I have a powerful one for preparing [registering?] paper for binding) and use a loop antenna, diode, and my Keithley.  However, I think the second part of this 

http://www.physics.sfsu.edu/~lea/courses/ugrad/460notes5.PDF <http://www.physics.sfsu.edu/~lea/courses/ugrad/460notes5.PDF>  does all.  


bc …  may have misunderstood.


BTW,  are we going to have an "off topic”  list serve?  

> On 2021/Feb/09, at 11:01, John Denker via Phys-l <phys-l@mail.phys-l.org> wrote:
>
> On 2/9/21 10:14 AM, David Ward wrote:
>
> > I recognize that a neutron has a non-zero magnetic moment, that it is
> > a collection of quarks with a total electric charge of zero. Here's
> > the student question: If a neutron were made to move, would its
> > electromagnetic nature result in EM wave propagation?
> >
> > My first answer is no, but there is that magnetic moment and the
> > substructure of the neutron. A cursory glance with Google led to one
> > or two hits where people implied it might emit.
>
> The short answer is yes, if you wiggle a neutron, it will radiate
> (except maybe on a set of measure zero, if you wiggle it in just
> the wrong way).
>
> I don't have a nice simple explanation of why, which probably
> means I don't understand the topic as well as I should ... but
> here's the best I can do.
>
> E) You may be familiar a radio antenna in the form of an electric
> dipole. Just a wire.  Electrons run up and down the wire. The E
> field of the electrons does the work.
> M) There are also loop antennas.  A loop of one or more turns of
> wire. AC current flows in the loop. Changing magnetic field.
> Radiation.
>
> A neutron looks like a magnetic dipole. So wiggling a neutron
> will look more like item (M) than item (E) above. The pattern
> of radiation in space will be different from what you would get
> from an electric dipole.  

much cut  

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