Search found 48 matches
- Sat Dec 19, 2009 11:05 am
- Forum: Science
- Topic: Uncertainty in calculations
- Replies: 12
- Views: 16237
Re: Uncertainty in calculations
So, you to make sure it is understood correctly. Imprecise measurements of parameters or initial conditions, might lead to imprecision of a prediction. Yes. There is even a uncertainty principle. It says, that you cannot measure two correlated thinks with infinite precision. For example, if you wan...
- Fri Dec 18, 2009 10:47 am
- Forum: New Users Start Here
- Topic: LHC exhibition in Germany
- Replies: 4
- Views: 6865
Re: LHC exhibition in Germany
Yes, its based on the exhibition done in Berlin last year. It has been transformed into a mobile one, so that it can been shown around the country. By the way, the Berlin exhibition had about 30.000 visitors
- Fri Dec 18, 2009 10:40 am
- Forum: Science
- Topic: Uncertainty in calculations
- Replies: 12
- Views: 16237
Re: Uncertainty in calculations
Which particles do you mean? The protons in the beam are not treated individually. It's also not neccesary. And all reconstructed particles in the experiment are using measurements. You can calculate back wards using the measured paricles to get the particles which decayed (reconstruct their mass an...
- Thu Dec 17, 2009 6:26 pm
- Forum: LHCb
- Topic: Q&A with a LHCb expert
- Replies: 6
- Views: 17447
Re: Q&A with a LHCb expert
At what processes do you look? Of course there are lot of things various people look for (even directly for the Higgs). But there are a few major studies: * The Tree-level determination of gamma * Charmless charged two-body B decays * Measurement of mixing-induced CP violation in B_s -> J/psi phi * ...
- Thu Dec 17, 2009 6:25 pm
- Forum: LHCb
- Topic: Q&A with a LHCb expert
- Replies: 6
- Views: 17447
Re: Q&A with a LHCb expert
How do you measure it? In an analyse you look at a specific process (see below). Lets take Bs -> J/Psi (mu+ mu-) Phi(K+ K-) as an example (In this decay the final state y and ay are the same, so look at b going into this state and anti-b going into this state). In a first step the event is reconstru...
- Thu Dec 17, 2009 6:24 pm
- Forum: LHCb
- Topic: Q&A with a LHCb expert
- Replies: 6
- Views: 17447
Re: Q&A with a LHCb expert
A tiny bit of theory Within the standard model (SM) there is only one place, where you can generate such processes. It is the CKM matrix (Cabibbo, Kobayashi, Maskawa). This matrix describes, how you can change a downtyp quark (d,s,b) into an uptyp quark (u,c,t) via the weak interaction (emitting a W...
- Thu Dec 17, 2009 6:23 pm
- Forum: LHCb
- Topic: Q&A with a LHCb expert
- Replies: 6
- Views: 17447
Re: Q&A with a LHCb expert
Motivation It all starts with the biggest asymmetry one can measure: our universe :) . When the universe was cooling down, photons (radiation) started to converted into particle and antiparticle. And particles and antiparticles annihilated into photons. So one would expect some kind of equilibrium b...
- Thu Dec 17, 2009 6:22 pm
- Forum: LHCb
- Topic: Q&A with a LHCb expert
- Replies: 6
- Views: 17447
Re: Q&A with a LHCb expert
WOW, I am an expert :D Okay, i tried to summarise the informations. But first i have to say that i am not an expert on the theory or the final results LHCb wants to measure. Nevertheless i picked up some informations from various talks given about these subjects, which i will try to explain in the n...
- Thu Dec 17, 2009 6:08 pm
- Forum: LHCb
- Topic: Event Display
- Replies: 12
- Views: 33750
Re: Event Display
As promised in the live chat, i asked for the colour codes. Turns out, not as simple as one would think. So i hope i understood this correctly. The program that produces this Plots is called Panoramix. This package visualises all objects, that can be generated by other LHCb software packages. So wha...
- Mon Dec 14, 2009 2:16 pm
- Forum: The Accelerator
- Topic: basic accelerator theory from a great discussion in chat
- Replies: 7
- Views: 19038
Re: basic accelerator theory from a great discussion in chat
So from an engineers POV the LHC is a very complex control loop with lots of non-independent tuning parameters and lots of disturbances. Now I have an idea why there was LHC@Home to simulate the behavior of the beams. I wonder if they have to find new settings after the break, small hysteretic effe...
- Sun Dec 13, 2009 4:44 pm
- Forum: The Accelerator
- Topic: LHC Theme Song ?
- Replies: 13
- Views: 17189
Re: LHC Theme Song ?
Yeah, it is really all one needs to know about the LHC in just under 5min.DCWhitworth wrote: I happen to think it's the best explanation of the LHC I've ever come across. Probably what got me interested in it in the frst place.
- Sun Dec 13, 2009 4:27 pm
- Forum: The Accelerator
- Topic: LHC Theme Song ?
- Replies: 13
- Views: 17189
Re: LHC Theme Song ?
Not bad.
Of course, there is always the Large Hadron Rap:
http://www.youtube.com/watch?v=j50ZssEojtM
Of course, there is always the Large Hadron Rap:
http://www.youtube.com/watch?v=j50ZssEojtM
- Sat Dec 12, 2009 9:44 pm
- Forum: New Users Start Here
- Topic: LHC exhibition in Germany
- Replies: 4
- Views: 6865
LHC exhibition in Germany
If you are in Germany, look out for the exhibition "Die Weltmaschine". It presents spare pieces from the experiments and you can get in direct contact with physisits working at the LHC experiments.
It is currently in Heidelberg until the 20th of December. In January it will be in Frankfurt.
It is currently in Heidelberg until the 20th of December. In January it will be in Frankfurt.
- Sat Dec 12, 2009 9:36 pm
- Forum: New Users Start Here
- Topic: Hello to all
- Replies: 7
- Views: 10195
Re: Hello to all
Please somebody explain me: What is a color charge? ;-) It is the charge of the strong force ;) Think of it the same way as about electric charge. The only difference is, that there is not only 2 kinds (+ and -), but three types of charge. As you have to name it someway, someone choose red, green a...
- Sat Dec 12, 2009 6:24 pm
- Forum: New Users Start Here
- Topic: Hello to all
- Replies: 7
- Views: 10195
Re: Hello to all
Please somebody explain me: What is a color charge? ;-) It is the charge of the strong force ;) Think of it the same way as about electric charge. The only difference is, that there is not only 2 kinds (+ and -), but three types of charge. As you have to name it someway, someone choose red, green a...