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On the Flavor Problem in Strongly Coupled Theories - THEP Mainz

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2.5. Hierarchies <strong>in</strong> Quark Masses and Mix<strong>in</strong>gs and <strong>the</strong> RS GIM Mechanism 87<br />

with <strong>the</strong> overlap <strong>in</strong>tegrals<br />

(δq)ij = 2π<br />

� 1<br />

Lɛ ɛ<br />

(δQ)ij = 2π<br />

Lɛ<br />

� 1<br />

ɛ<br />

(∆g q<br />

h )ij = 2π<br />

� 1<br />

Lɛ ɛ<br />

dt a<br />

Q †<br />

i<br />

SQ<br />

q †<br />

dt ai Sq<br />

i (t)SQ j (t) aQ<br />

j<br />

i (t)Sq j<br />

(t) aq<br />

j<br />

q †<br />

dt δ(t − 1) ai Sq<br />

i (t)Y † q S Q<br />

j (t) aQ<br />

j . (2.179)<br />

The last <strong>in</strong>tegral corresponds to <strong>the</strong> second Yukawa coupl<strong>in</strong>g <strong>in</strong> (2.177) and must be<br />

evaluated with a properly regularized delta function, see [118, p.135f.]. It will represent<br />

<strong>the</strong> lead<strong>in</strong>g term <strong>in</strong> Higgs mediated flavor violat<strong>in</strong>g processes, because it is not chirally<br />

suppressed. However, for all processes considered it can still be neglected, because <strong>in</strong><br />

<strong>the</strong> case of ∆F = 1 currents <strong>the</strong> flavor-conserv<strong>in</strong>g vertex is chirally suppressed and for<br />

∆F = 2 currents it is smaller <strong>the</strong>n <strong>the</strong> tensor structure (2.176) by a factor v 2 /M 2 KK .<br />

It is however important <strong>in</strong> Higgs physics [127].<br />

In <strong>the</strong> ZMA, <strong>the</strong> above matrices simplify considerably,<br />

∆Q → U q†<br />

L diag<br />

�<br />

F 2 (cQi )<br />

�<br />

U<br />

3 + 2cQi<br />

q<br />

L ,<br />

∆q → U q†<br />

R diag<br />

�<br />

F 2 (cqi )<br />

�<br />

U<br />

3 + 2cqi<br />

q<br />

R ,<br />

∆ ′ Q → U q†<br />

L diag<br />

�<br />

5 + 2cQi<br />

and<br />

where<br />

� �<br />

�∆Q<br />

mn⊗ � ∆q<br />

� ′<br />

�<br />

∆ ′ q → U q†<br />

R diag<br />

m ′ n ′ → �<br />

i,j<br />

� q† �<br />

UL mi<br />

( � ∆Qq)ij = F 2 (cQi )<br />

3 + 2cQi<br />

2(3 + 2cQi )2 F 2 (cQi )<br />

�<br />

5 + 2cqi<br />

2(3 + 2cqi )2 F 2 (cqi )<br />

�<br />

� q�<br />

UL <strong>in</strong> ( � ∆Qq)ij<br />

�<br />

U q<br />

L ,<br />

U q<br />

R , (2.180)<br />

� q† �<br />

UR m ′ j<br />

� q �<br />

UR jn ′ , (2.181)<br />

3 + cQi + cqj F<br />

2(2 + cQi + cqj )<br />

2 (cqj )<br />

, (2.182)<br />

3 + 2cqj<br />

and analogue for <strong>the</strong> rema<strong>in</strong><strong>in</strong>g comb<strong>in</strong>ations of <strong>in</strong>dices Q and q. Because of <strong>the</strong><br />

v/MKK suppression <strong>in</strong> (2.150), <strong>the</strong> ε structures vanish <strong>in</strong> <strong>the</strong> ZMA. Us<strong>in</strong>g <strong>the</strong> fact that<br />

all ci parameters except cu3 are very close to −1/2, it is a reasonable approximation<br />

to replace (3 + cQi + cqj )/(2 + cQi + cqj ) by 2, <strong>in</strong> which case we obta<strong>in</strong> <strong>the</strong> approximate<br />

result<br />

�∆A ⊗ � ∆B → ∆A ∆B , (2.183)

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