To get you all set for the presentations on the Higgs particle search coming up on Tuesday, December 13th, I’ve written a sequence of three articles about the Standard Model Higgs particle, the simplest form of Higgs particle that might be present in nature, and the one that is the main target, during Phase 1 of the search for the Higgs particle, that the Large Hadron Collider (LHC) experiments are aiming to discover or rule out. Links to the three articles now appear at the bottom of this page, which provides context by describing the Standard Model Higgs particle in some detail.
- Article 1 is about producing the Standard Model Higgs particle,
- Article 2 is about how the (lightweight) Standard Model Higgs particle decays, and
- Article 3 combines the previous two into a search strategy, and into a program for studying the Standard Model Higgs in detail if/when it is found. Article 3 also points to a couple of older articles that cover important details highly relevant, in my judgment, to Tuesday’s presentation.
Re: Article 3, which is new today — I should warn you that I’m suffering from jet lag, so … well, you know what that might mean. I hope there’s nothing amiss, and that the prose is readable! Also, article 3 is long, and you might want to read it in two sittings, divided at what will be an obvious point.
One reason I’m very tired today is that last night’s flight to Geneva was shortened by extraordinary 200 mile-per-hour (320 kilometer-per-hour) tail winds for the first couple of hours. We had a ground speed over 700 miles per hour for a while (1150 km per hour)! The pilots told me they later had to slow the plane’s air speed down significantly in order that we wouldn’t arrive before the customs officials at the Geneva airport start their day. At normal air speed we apparently would have made the trip in less than 5 1/2 hours!
10 Responses
Did you check for Cerenkov radiation outside your window? 🙂
Sorry, couldn’t help myself.
Andy (Andy Haas, professor at New York University, member of ATLAS) — sorry to hear you couldn’t help yourself. While you’re feeling so generous, want to tell us how many sigmas is the Higgs signal at ATLAS? 😉
David, I went back and read Matt’s post. Gotcha. Thanks for taking the time with me. I’m a classicist, not a physicist, so anything that involves comparing two numbers relative to each other is always going to confuse me!
David, I got that. But Matt mentioned the ground speed in his original article, I was just confused about his final sentence “At normal air speed we apparently would have made the trip in less than 5 1/2 hours!”. Normal, would, I think, be without the “extraordinary” 200 mph tail winds. You just posted that normal air speed means a trip of almost eight hours. I think Matt meant to say (maybe) that at the abnormal speed they were traveling, the trip would have taken 5 1/2 hours, but the crew slowed down the plane so they would arrive after the custom officials started their jobs.
The tail winds (the speed of the air with respect to the ground) don’t affect the air speed (the speed of the plane with respect to the air). Due to the extraordinary tail winds (the speed of the air with respect to the ground), normal air speed (of the plane with respect to the air) would have resulted in an abnormal ground speed (of the plane with respect to the ground), and thus a shorter trip, as Matt states. This is a great illustration of the point in the linked article, that the speed of something (plane or air) always has to be stated as relative to something else (air or ground).
Earl – you are right that what I wrote was confusing. I mean that if we had traveled at normal air speed instead of the slower speed that the pilots chose, in order to make our arrival at a reasonable hour. So yes, your interpretation is right. And I think David overestimated the usual length of the trip; the flight time is shorter than that. [Maybe there’s a cushion built in for air traffic issues at Newark?]
Your last sentence is a bit confusing. You are saying that at normal air speeds (without the 200 mph tail wind) you would have made the flight in 5 1/2 hours. OK, but why the exclamation point? You didn’t say how long it took you at the increased air speed, so, as far as I can see, we have no idea of the difference (unless I fire up Google Earth and plot the geodesic and figure out the time to traverse the arc given an 700 mph ground speed over the “first couple of hours.” Jet lag will do this to you! 🙂
Earl, “air speed” refers to the speed of the plane with respect to the air, not the speed of the air with respect to the ground. To find the standard flight time, I checked United.com, which showed a 7 hour 50 minute nonstop flight from Newark to Geneva.