Compute the Turaev cobracket of the correction term

Compute the Turaev cobracket of the element j in the symplectic-invariant degree-six ideal component \mathfrak{j}_{g,1}(6)^{\mathrm{Sp}}, where j is the correction term appearing in the decomposition of the first Galois obstruction \sigma_3(g).

Background

The paper expresses the first Galois obstruction as σ3(g)=180(g1)gεj\sigma_3(g)=180(g-1)g\,\varepsilon-j, where ε\varepsilon lies in the kernel of the Enomoto–Satoh trace map and jjg,1(6)Spj\in\mathfrak{j}_{g,1}(6)^{\mathrm{Sp}} is a correction term arising from the ideal that vanishes after passage to the closed-surface setting. The authors explicitly compute ES6(σ3(g))=ES6(j)ES_6(\sigma_3(g))=ES_6(-j), but they do not compute the Turaev cobracket of jj.

References

Is it possible to compute the Turaev cobracket of the element $j\in \mathfrak{j}_{g,1}(6){\mathrm{Sp}$?

The first Galois obstruction in the Johnson cokernel  (2608.17673 - Morita et al., 18 Aug 2026) in Section 7, Section “Questions,” first Question environment

Is it true that $$ \overline{ES}{4k+2}(\sigma{2k+1}(g))=0? $$

The first Galois obstruction in the Johnson cokernel  (2608.17673 - Morita et al., 18 Aug 2026) in Section 7, Section “Questions,” second Question environment (label probles)