Proposition 5.20.4 (Lelong–Poincaré).0C02CD3B5D59 Let $s\in \mathrm{H}^0(X,L)$ be non-zero and $h$ be a Hermitian metric on $L$. Then
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5.20.5
\begin{equation} c_1(L,h)+\mathrm{dd}^{\mathrm{c}}\log |s|_ h^2=[Z(s)], \end{equation}
where $Z(s)$ is the zero divisor defined by $s$ and $[\bullet ]$ denote the associated current of integration.
Proof. In a holomorphic frame $e$ of $L$, write $s=fe$ and $|e|_h^2=\exp(-\rho)$. Then $\log|s|_h^2=\log|f|^2-\rho$ and $c_1(L,h)=\mathrm{dd}^{\mathrm c}\rho$. The normalized Poincaré--Lelong formula gives $\mathrm{dd}^{\mathrm c}\log|f|^2=[Z(f)]$. Substitution proves
\[c_1(L,h)+\mathrm{dd}^{\mathrm c}\log|s|_h^2=[Z(s)].\]
Changing the frame multiplies $f$ by a nowhere-vanishing holomorphic function; its logarithmic squared modulus is pluriharmonic, so the local identities agree on overlaps. This also checks the factor $1/(2\pi)$ in the normalization.
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