Hikes and Trips

Hello everyone!

Been a busy week (as usual). My thesis continues to progress and I've set my goal to be done by graduation. This may seem kind of a no brainer to most of you, but I was offered an extra month's pay to stick around and finish up the thesis and teach. I'm ready to be done, however. So the goal is to finish the bloody thing in the next month. I have two chapters left and the appendices to do, so that all should be doable assuming I can get my code to obey me.

I did go to a very neat seminar at CERN last week that I wanted to share with the physics types among you. If you are uninterested, skip a few paragraphs. This seminar was about the next generation of particle accelerators. Basically the LHC is ludicrously huge and expensive for what seems to be increasingly diminishing returns. We can get 10% higher energies for over 100% the cost in essence. (I pulled those numbers out of nowhere, but it reflects the general trend.) This seminar was about a new form of particle acceleration which I thought was very cool. It's so new it isn't yet an official CERN experiment and they are in the approvals phase. It is called plasma wake acceleration.

I won't go into the detail that the seminar did (mostly because I didn't understand much more than the big picture), but I thought it worked in a very cool way. The LHC beam lines (and for all I know all other particle accelerator beams) are under a vacuum to ensure that the beams don't interact with anything besides each other. The particles in the beams are accelerated via magnets up to near light speed and energies in the TeV range (Tera electron volt). It takes many revolutions and a slow ramping up of the magnets for this to occur. Plasma wake acceleration uses a plasma as the medium used to accelerate particles.

Plasma is a state of matter where electrons are not really associated with any particular atomic nucleus, allowing them to move freely. If you shoot a positive charge through a plasma, all of the positively charged nuclei floating around in it are pushed off to the side, repelled by the electric field of the positive charge. When moving at relativistic speeds, a charged particle's electric field is forced into a ring around the particle perpendicular to the direction of motion. This means that the positive charges in the plasma are shot strait sideways by a very strong electric field. The impulse is high too since it acts over a very short period of time, giving it a nice strong shove out of the way.

Once the moving particle has passed through, there is a gap in the plasma where there are no positive charges, thus leaving it very strongly negatively charged. The result is that the positive charges in the plasma collapse back inwards and for a split instant form a very dense positive charge before going back into equilibrium. This happens in the wake of the positively charged beam of particles shooting through the plasma, meaning that the effect in essence chases after the beam. If you inject the particles you wish to accelerate at the right point, they will be pushed by their like signed charges and pulled by their opposite signed charges and be very effectively accelerated.

One of the beauties of this approach is that the original beam you use to set up the plasma wake becomes separated into bunches of charge, setting up waves of charged particles with a wavelength relating to the natural frequency of the plasma. This not only makes the total positive charge stronger, but also means that it is easy to know when to inject your protons or electrons that you want accelerated. Of course the initial beam loses energy as it passes through the plasma, so this method is only good over a few hundred meters at a time, but that can be enough, especially if done in stages. Ultimately this method of acceleration can, in a linear accelerator (as opposed to a circular one like the LHC) add around 1 GeV per meter of plasma to electrons. This means that in a kilometer or so, one can reach LHC level energies. Which is mind blowing. I enjoyed the seminar and wanted to share it with people. I may have some of the process a little wrong, but I think I have the general idea.

Anyway, for those who weren't interested in physics, this is where you should pick up. Hiking! I went with Polly, Laurel, and Morag (the usual crew) for a nice hike on one of the hills sort of in the middle of the valley. It counts as a hill in a valley because it isn't a part of the alps, nor a part of the Jura mountains. It was an area the Polly had been in before with her boyfriend and his mother and it was a delightful romp through the forest on a hill. Almost a mountain.

There was one slight problem in that thought the sun was bright and it was warm in the valley, standing on a reasonably exposed hilltop is rather cold. Particularly when there is heavy wind that is constantly blowing a frozen melody through the trees. Once we got moving it wasn't so bad, particularly when we were in the wooded areas, and the wind was much less further down.

There was one other disconcerting thing about the hike... We drove to the top and hiked down, then back up, rather than climbing a mountain and coming back down. This absolutely defies everything I believe about hiking and was only allowable because we spent most of the time at the same altitude traversing on roads and trails rather than going down to the bottom and coming allll the way back up. We had a great view the entire time, which was also nice.

Most of the woods were pine, which made me very happy since I have spent so much of my life hiking in Seattle. Actually the woods themselves were very Cascade-like, except that there was less undergrowth and no sword ferns. It was nice to be around real trees for a change. Most of the ones down in the valley are aspen, oak, or other leafy trees which while pretty don't quite have the right smell for a good hike.

We had lunch at a little rather muddy pond in a real live honest to God meadow (something that isn't as common in the Cascades) with wild flowers creeping up because spring is starting (in spite of the layer of ice that still occasionally covers car windshields in the mornings). We all packed our own lunches, though we did share a bit. I shared strawberries purchased at the Ferney Voltaire market that were perfectly ripe and delicious on the way to lunch, so I was exempt. Also I just had a sandwich, which isn't a very sharing-oriented food.

We ran into a number of people on the way (including a dog that came nosing around while we were eating). Some of them looked SERIOUS with the extendable poles, north face jackets (well, ok, I was wearing a north face jacket) and high end hiking boots. Granted I was wearing high end running shoes, but they're high end running shoes with something like 500 miles on them, not to mention lots of walking in them. They need replacing since I can see my feet through them in several areas. Still going though! Asics knows it stuff.

In all the hike was about four hours and was delightful. We weren't even that cold except for the beginning of the hike and a brief stop on the way back to take pictures of the Alps side of things. That was very windy and very cold, even relative to the start of the hike. We went back and enjoyed earl grey tea (which is much better coming from the UK than in the group packs you get in the US) and some cookies (biscuits, I suppose since they were English too) that have the wonderful name of Chocolate Digestives. I can't imagine a less appealing word to attach chocolate to, but they do taste nice and are excellent for dipping in tea.

One last thing to bring you all up to date on before signing off: I am going to Istanbul! As most of you probably know. Laurel and I are the only ones going, but we've got a hostel booked and flights purchased. It should be a great trip and I have approximately 328 things to see in the three full days we have there. Coming back should be fun since I get back and the next day fly back to Omaha. Wheeee! Hehe. I will have daily blog posts while I'm there (12th through 16th).

Ciao!