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This is exact to O ( λ ω$_{c}$ $_{E$_{f}$}$), where λ ’s are the dimensionless coupling constants exhibited b elow. In the con tinuum approximation for fermions near the fermi-energy, γ ( k , k $^{′}$) ∝ i ( k × k $^{′}$). The pairing vertex is then 

<img src='content_image/371127.jpg'>

Since Re χ ( k − k $^{′}$) , ω ) < 0 for − ω$_{c}$ < ω < ω$_{c}$ , independent of momentum, the p airing symmetry is given simply by expressing ( k × k $^{′}$) 2 in separable form : 

<img src='content_image/371126.jpg'>

Pairing interaction in the s -wave channel is repulsive, that in the two d -wave channels is equally attractive, and in the odd-parity channels is zero. The factor i in γ ( k , k $^{′}$), present be- cause the coupling is to fluctuations of time-reversal odd operators, is crucial in determining the sign of the interactions of the pairing vertex. 

To estimate T$_{c}$ , we use what has been discussed in Sec.(II) about the effect of inelastic 

