$p$-adic field 2.2.8.54a1.956

• Label: 2.2.8.54a1.956
• Base: \(\Q_{2}\)
• Degree: \(16\)
• e: \(8\)
• f: \(2\)
• c: \(54\)
• Galois group: $C_4^2.D_4$ (as 16T360)

Defining polynomial

$( x^{2} + x + 1 )^{8} + 4 ( x^{2} + x + 1 )^{7} + 4 x ( x^{2} + x + 1 )^{6} + \left(8 x + 8\right) ( x^{2} + x + 1 )^{5} + \left(16 x + 2\right) ( x^{2} + x + 1 )^{4} + \left(16 x + 16\right) ( x^{2} + x + 1 )^{3} + 8 ( x^{2} + x + 1 )^{2} + 2$

Invariants

Base field:	$\Q_{2}$
Degree $d$:	$16$
Ramification index $e$:	$8$
Residue field degree $f$:	$2$
Discriminant exponent $c$:	$54$
Discriminant root field:	$\Q_{2}$
Root number:	$-1$
$\Aut(K/\Q_{2})$:	$C_4$
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:	$[1, 5, 13, 21]$
Roots of unity:	$12 = (2^{ 2 } - 1) \cdot 2^{ 2 }$

Intermediate fields

$\Q_{2}(\sqrt{5})$, $\Q_{2}(\sqrt{-1})$, $\Q_{2}(\sqrt{-5})$, 2.2.2.4a1.1, 2.2.4.18a1.7

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

Canonical tower

Unramified subfield:	$\Q_{2}(\sqrt{5})$ $\cong \Q_{2}(t)$ where $t$ is a root of \( x^{2} + x + 1 \)
Relative Eisenstein polynomial:	\( x^{8} + 8 t x^{7} + \left(4 t + 4\right) x^{6} + 8 t x^{5} + \left(8 t + 2\right) x^{4} + 16 t x^{3} + 8 x^{2} + 16 x + 2 \) $\ \in\Q_{2}(t)[x]$

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:	$128$
Galois group:	$C_4^2.D_4$ (as 16T360)
Inertia group:	not computed
Wild inertia group:	not computed
Galois unramified degree:	$2$
Galois tame degree:	$1$
Galois Artin slopes:	$[2, 2, 3, \frac{7}{2}, 4, \frac{9}{2}]$
Galois Swan slopes:	$[1,1,2,\frac{5}{2},3,\frac{7}{2}]$
Galois mean slope:	$3.96875$
Galois splitting model:	not computed