Properties

Label 2.1.8.31a1.3
Base \(\Q_{2}\)
Degree \(8\)
e \(8\)
f \(1\)
c \(31\)
Galois group $Z_8 : Z_8^\times$ (as 8T15)

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Defining polynomial

\(x^{8} + 16 x^{5} + 34\) Copy content Toggle raw display

Invariants

Base field: $\Q_{2}$
Degree $d$: $8$
Ramification index $e$: $8$
Residue field degree $f$: $1$
Discriminant exponent $c$: $31$
Discriminant root field: $\Q_{2}(\sqrt{2})$
Root number: $1$
$\Aut(K/\Q_{2})$: $C_2$
This field is not Galois over $\Q_{2}.$
Visible Artin slopes:$[3, 4, 5]$
Visible Swan slopes:$[2,3,4]$
Means:$\langle1, 2, 3\rangle$
Rams:$(2, 4, 8)$
Jump set:$[1, 3, 7, 15]$
Roots of unity:$2$

Intermediate fields

$\Q_{2}(\sqrt{-2})$, 2.1.4.11a1.1

Fields in the database are given up to isomorphism. Isomorphic intermediate fields are shown with their multiplicities.

Canonical tower

Unramified subfield:$\Q_{2}$
Relative Eisenstein polynomial: \( x^{8} + 16 x^{5} + 34 \) Copy content Toggle raw display

Ramification polygon

Residual polynomials:$z^4 + 1$,$z^2 + 1$,$z + 1$
Associated inertia:$1$,$1$,$1$
Indices of inseparability:$[24, 16, 8, 0]$

Invariants of the Galois closure

Galois degree: $32$
Galois group: $D_8:C_2$ (as 8T15)
Inertia group: $\SD_{16}$ (as 8T8)
Wild inertia group: $\SD_{16}$
Galois unramified degree: $2$
Galois tame degree: $1$
Galois Artin slopes: $[2, 3, 4, 5]$
Galois Swan slopes: $[1,2,3,4]$
Galois mean slope: $4.0$
Galois splitting model:$x^{8} - 8 x^{4} + 18$