How do I derive T (transmission) in a rectangular potential barrier with E > V0?

knightil
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Barrier potential, E> V0

V(X) = 0 ( x < 0 )
= V0 ( 0 < x < a )
= 0 ( x> a )

Psi(x)1 = Aexp[ik1x] + B exp[-ik1x]
Psi(x)2 = Cexp[ik2x] + D exp[-ik2x]
Psi(x)3 = Fexp[ik1x] + G exp[-ik1x] ( K3= K1 so I put k1 )

and G = 0 because there is no reflection,

I used B.C so I get 4 functions
and I calculated and I found what is A/F .
but there is problem
exp[ik2a] and exp[-ik2a], I changed into sine and cosine
but there is remaind exp[ik1a]

I have to derive T(transmission) but there is no K1
how do I eliminate that?

this problem is from Introductory Nuclear Physics chap.2 - 1
please help me :(
 
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nickjer said:
You definitely should show more work, since I have no idea what steps you are doing and where you went wrong. But wikipedia does a very similar problem:

http://en.wikipedia.org/wiki/Rectangular_potential_barrier

my Q was how I change t to T in wikipedia where you link.
why there is sine fomula?

but, finally I've done :)
thank you
 
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