Muon Decay Constant: Find Mean Lifetime & Lambda

[RK1992]

muon decay constant/ muon flux

where can i find the decay constant of a muon (the lambda which appears in):
[URL]http://upload.wikimedia.org/math/3/f/2/3f28b1c0d4362b86a89f976d83d81070.png[/URL]

thanks

edit:
oh the wiki page http://en.wikipedia.org/wiki/Exponential_decay
gives the relationship that the decay constant is the reciprocal of the mean lifetime
is that correct?

 

[phyzguy]

Typically you will find the half-life tabulated, which for the muon is about 2 microseconds. As the Wikipedia article you cited states, the decay constant is related to the half-life as follows:
$$\lambda = \frac{ln(2)}{t_{1/2}}$$

 

[Bob S]

See top of second page in this URL for both positive and negative-charged muon lifetimes:

http://pdg.lbl.gov/2004/listings/s004.pdf

Bob S

 

[Vanadium 50]

Bob seems to be suggesting that positively and negatively charged muons have different lifetimes. This is not the case.

 

[RK1992]

Bob seems to be suggesting that positively and negatively charged muons have different lifetimes. This is not the case.

i can see that the ratio is almost 1:1 for the mean lifetimes :)

but my other question is where on Earth are you supposed to obtain simple data on muon flux at different altitudes - like at the height where they are generally created and at ground level? I am not looking for partial differential equations and all that, just for example the number of muons through a metre sqaured area per second at a height of 5000m and the number of muons through a metre squared per second at ground level

 

[Bob S]

Bob seems to be suggesting that positively and negatively charged muons have different lifetimes. This is not the case.

The measurement of both positive and negative charged muon lifetimes is an important test to verify that they are equal, as required by CPT invariance. See second table on page 2 of

http://pdg.lbl.gov/2004/listings/s004.pdf

Bob S

 

[Vanadium 50]

The measurement of both positive and negative charged muon lifetimes is an important test to verify that they are equal, as required by CPT invariance.

True, but irrelevant to what the OP asked. Please don't sidetrack the thread.