Re: Cathode vibration- how to dampen?

["Daniel S. Carman" <carman@jlab.org>]

Elke,

I understand from recent conversations that Tim has a list of
vibration sources in the Hall.  We will look to calculate the
natural frequency of vibration of the cathodes and then perhaps
devise a simple measurement to verify.  I will keep you informed
on what we learn.


				Regards,

					Daniel


**********************************************************************
*                                                                    *
* Dr. Daniel S. Carman                   e-mail : carman@jlab.org    *
* Staff Scientist                        office : (757)-269-5586     *
* Jefferson Laboratory                   web: www.jlab.org/~carman   *
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On Fri, 22 Feb 2008, Elke-Caroline Aschenauer wrote:

> On Wed, 20 Feb 2008, Tim Whitlatch wrote:
>
> Dear all,
>
> one other thing to investigate before doing a lot work is what is in the
> environment of the fdc which could cause vibrations, like pumps.
>
> Cheers elke
>
>
>
> > Date: Wed, 20 Feb 2008 14:22:39 -0500
> > From: Tim Whitlatch <whitey@jlab.org>
> > To: wcrahen <wcrahen@jlab.org>, halld-tracking-hw@jlab.org
> > Subject: Re: Cathode vibration- how to dampen?
> >
> > Thanks for the heads up Bill. This may or may not be an issue. Dan has
> > proposed doing a simple test to determine what frequencies drive the
> > oscillations (visible) in the cathode plane. He said the equipment is
> > available. Before we spend any time on coming up with solutions, let's
> > see what the natural frequencies of the plane are and what driving
> > frequencies it will be subject to by way of Dan's simple test. There may
> > be no issue at all.
> >
> > Cheers,
> >
> >        Tim
> >
> > wcrahen wrote:
> > > Brian stopped by to discuss vibration of the cathode planes in the
> > > FDC- and any strategies we might have to eliminate motion. He would
> > > like to set up a meeting. The  first thought is to attach the cathode
> > > to the ground plane with some rohacel plugs (we can't have a complete
> > > ring if we flow gas through the center).
> >
> >
>
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