Lab Book 2014_05_27 Special Relativity, Proper Acceleration, and Magnet Prep

Meetings, Magnets, and Special Relativity

Spent the morning attending a meeting and getting to do just a tiny little bit of special relativity research, regarding proper acceleration in the instantaneously moving rest frame. The rest of the day was spent debugging, first the liquid nitrogen Dewar, and then the leak detector. The leak detector is still not up to snuff. Prep work was done for lifting the magnet that will supply the quenching field for the superconducting samples.

New to these posts?
The hole theory of superconductivity, a BCS compatible modle, predicts that when a superocnductor is brought back to its normal state quickly, it will emit x-rays. We plan to experimentally verify this or set a new lower limit for its detection. Scroll to the bottom for more complete information of what this physics experiment is about and what we hope to achieve.

Relativistic range work:
Reviewed and followed Brehme’s derivation of proper acceleration and its meaning. Proper acceleration is used in the Walter rapidity paper as well as all my rapidity style derivations and winds up in the MacColl and Shahin papers as well. Here are my notes on Brehme’s interpretation:

For the full scratch-pad LaTex write up of the above notes see https://www.writelatex.com/read/jrvqwgbqbvvj.

Liquid Nitrogen Dewar Refill

An attempt was made to fill the liquid nitrogen Dewar through the lid rather than through the liquid nozzle again. This resulted in the lid once again not being seated properly and the Dewar not properly developing pressure. The lid is to be reseated. Upon reseating, the pressure slowly climbed again and we were able to get liquid nitrogen out of the Dewar.

Magnet Lift and Move

The short bar was placed back in the lifting A-frame. The A-frame was test fit and does just straddle the magnet.

Ace Bolt and Screw has located the eye bolts we need to lift the magnet! They’re in Dallas and hopefully will be here by Thursday. It'll be time for another field trip with the kids!

Background

Hirsch's theory of hole superconductivity proposes a new BCS-compatible model of Cooper pair formation when superconducting materials phase transition from their normal to their superconducting state[1]. One of the experimentally verifiable predictions of his theory is that when a superconductor rapidly transitions, (quenches), back to its normal state, it will emit x-rays, (colloquially referred to here as H-rays because it's Hirsch's theory).

A superconductor can be rapidly transitioned back to its normal state by placing it in a strong magnetic field. The experiment being performed proposes to look for H-rays emitted by a Pb superconductor when it is quenched by a strong magnetic field.

The lab book entries in this series detail the preparation and execution of this experiment… mostly. I also have a few theory projects involving special relativity and quantum field theory. Occasionally, they appear in these pages.

Call for Input

If you have any ideas, questions, or comments, they're very welcome!

References

1. Hirsch, J. E., “Pair production and ionizing radiation from superconductors”, http://arxiv.org/abs/cond-mat/0508529

The Valentine's Day Magnetic Monopole

There's an assymetry to the form of the two Maxwell's equations shown in picture 1. While the divergence of the electric field is proportional to the electric charge density at a given point, the divergence of the magnetic field is equal to zero. This is typically explained in the following way. While we know that electrons, the fundamental electric charge carriers exist, evidence seems to indicate that magnetic monopoles, the particles that would carry magnetic 'charge', either don't exist, or, the energies required to create them are so high that they are exceedingly rare. That doesn't stop us from looking for them though! Keeping with the theme of Fairbank[1] and his academic progeny over the semester break, today's post is about the discovery of a magnetic monopole candidate event by one of the Fairbank's graduate students, Blas Cabrera[2]. Cabrera was utilizing a loop type of magnetic monopole detector. Its operation is in...

Cool Math Tricks: Deriving the Divergence, (Del or Nabla) into New (Cylindrical) Coordinate Systems

Now available as a Kindle ebook for 99 cents ! Get a spiffy ebook, and fund more physics The following is a pretty lengthy procedure, but converting the divergence, (nabla, del) operator between coordinate systems comes up pretty often. While there are tables for converting between common coordinate systems , there seem to be fewer explanations of the procedure for deriving the conversion, so here goes! What do we actually want? To convert the Cartesian nabla to the nabla for another coordinate system, say… cylindrical coordinates. What we’ll need: 1. The Cartesian Nabla: 2. A set of equations relating the Cartesian coordinates to cylindrical coordinates: 3. A set of equations relating the Cartesian basis vectors to the basis vectors of the new coordinate system: How to do it: Use the chain rule for differentiation to convert the derivatives with respect to the Cartesian variables to derivatives with respect to the cylindrical variables. The chain ...

More Cowbell! Record Production using Google Forms and Charts

First, the what : This article shows how to embed a new Google Form into any web page. To demonstrate ths, a chart and form that allow blog readers to control the recording levels of each instrument in Blue Oyster Cult's "(Don't Fear) The Reaper" is used. HTML code from the Google version of the form included on this page is shown and the parts that need to be modified are highlighted. Next, the why : Google recently released an e-mail form feature that allows users of Google Documents to create an e-mail a form that automatically places each user's input into an associated spreadsheet. As it turns out, with a little bit of work, the forms that are created by Google Docs can be embedded into any web page. Now, The Goods: Click on the instrument you want turned up, click the submit button and then refresh the page. Through the magic of Google Forms as soon as you click on submit and refresh this web page, the data chart will update immediately. Turn up the:...

Copasetic Flow

Search This Blog