Properties

Label 2.1.8.27a1.118
Base \(\Q_{2}\)
Degree \(8\)
e \(8\)
f \(1\)
c \(27\)
Galois group $(C_4^2 : C_2):C_2$ (as 8T26)

Related objects

Downloads

Learn more

Defining polynomial

\(x^{8} + 4 x^{6} + 8 x^{5} + 2 x^{4} + 16 x + 6\) Copy content Toggle raw display

Invariants

Base field: $\Q_{2}$
Degree $d$: $8$
Ramification index $e$: $8$
Residue field degree $f$: $1$
Discriminant exponent $c$: $27$
Discriminant root field: $\Q_{2}(\sqrt{-2\cdot 5})$
Root number: $i$
$\Aut(K/\Q_{2})$: $C_2$
This field is not Galois over $\Q_{2}.$
Visible Artin slopes:$[2, \frac{7}{2}, \frac{9}{2}]$
Visible Swan slopes:$[1,\frac{5}{2},\frac{7}{2}]$
Means:$\langle\frac{1}{2}, \frac{3}{2}, \frac{5}{2}\rangle$
Rams:$(1, 4, 8)$
Jump set:$[1, 2, 4, 16]$
Roots of unity:$2$

Intermediate fields

$\Q_{2}(\sqrt{-5})$, 2.1.4.9a1.5

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: \( x^{8} + 4 x^{6} + 8 x^{5} + 2 x^{4} + 16 x + 6 \) 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:$[20, 12, 4, 0]$

Invariants of the Galois closure

Galois degree: $64$
Galois group: $D_4:D_4$ (as 8T26)
Inertia group: $C_4\wr C_2$ (as 8T17)
Wild inertia group: $C_4\wr C_2$
Galois unramified degree: $2$
Galois tame degree: $1$
Galois Artin slopes: $[2, 3, \frac{7}{2}, 4, \frac{9}{2}]$
Galois Swan slopes: $[1,2,\frac{5}{2},3,\frac{7}{2}]$
Galois mean slope: $3.9375$
Galois splitting model:$x^{8} + 6 x^{4} + 6$