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Lab Book 2014_05_13 Leak Detector Work and Checks of Rotating Frames and Special Relativity

Lab Book 2014_05_13     Hamilton Carter               

After fixing the crusty battery cable in the car this morning, I got to do a little bit of work around the lab before the end of the day.  We met and discussed the special relativity work today as well.  Fermi-Walker transport makes sense as just being the acceleration normal to the tangential velocity that changes the direction of the tangential velocity.

The hose between the auxiliary roughing pump and the leak detector was attached.  The auxiliary pump is used to rough out the volum to be leak detected before using a valve on the leak detector to attach the built in diffusion pump to the volume to attain a much higher vacuum, (in the range of 10E-8 Torrs).

The added hose used the fittings I built a few weeks ago to attach the system.  There’s an intermediate piece that contains an O-ring that fits between the KF fitting on the hose and the pump assembly.
New KF fitting I constructed

O-ring fitting that fits between the two KF fittings

Break-away fitting clamp

Half of clamp enclosing hose and pump fitting with interfacing O-ring

Completely clamped connection

The liquid nitrogen Dewar still had liquid in it, but apparently the lid flange was leaking.  This was not allowing any pressure to build up and so the liquid nitrogen was not exiting the Dewar.  The liquid level was 26 inches as of about 4:30 PM today.  I’ll measure again tomorrow.  We may leak detect a very large liquid helium Dewar along with the glass and fiberglass Dewars.  I need to locate heating tape so we can heat up the Dewar to re-activate the active carbon filter inside.

I worked more on QFT in rotating frames as well.  My original calculations showing that gamma doesn’t participate in the transverse Lorentz force may be incorrect.  I’ve started a new derivation approaching the problem from the direction of four force.  The check and a few notes on Fermi-Walker transport can have been added to the paper positing that the number operator might not be valid for circular motion.

Current pdf version of relativistic work


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