Design a CP violation experiment with B-mesons in 1 hour

• Which accelerator do you want to use– e+e-, pp, pp, something else?– Fixed target, collider?Mention pros and cons of each option

• At which energy or energies would you run your favorite accelerator?

– Why?

• You decide you want to measure CP asymmetry in BJ/ KS, which has a branching ratio of 10-4. How many B particles must be produced to reach 1o accuracy on ?

• In the CP asymmetry you measure both BJ/KS and BJ/KS

– How would you tag the flavour of the B at “production”?

• Why is “production” in quotes?

– Are there intrinsic limitations?– What detectors do you need for tagging?

• To select BJ/KS and B+- backgrounds need to be rejected

– What are signatures/properties of signal and background that can be used to separate the two?

• Which can be used ‘online’ in a trigger?

– One of the two decays has a particular nasty background. Which one? How do you get rid of it, and what detectors do you need?

• Give the formula to reconstruct the “decay time” of a B meson in terms of directly “measurable” quantities.

– Why is “decay time” in quotes?– Which detectors are required, and what is there

relative importance?

• Make a sketch of your detector– How does it compare to current and planned

experiments?– If ambitious, estimate the cost and write a

proposal ;-)