$p$-adic field 2.2.8.36b18.22

• Label: 2.2.8.36b18.22
• Base: \(\Q_{2}\)
• Degree: \(16\)
• e: \(8\)
• f: \(2\)
• c: \(36\)
• Galois group: $C_2^5:C_4$ (as 16T227)

Defining polynomial

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

Invariants

Base field:	$\Q_{2}$
Degree $d$:	$16$
Ramification index $e$:	$8$
Residue field degree $f$:	$2$
Discriminant exponent $c$:	$36$
Discriminant root field:	$\Q_{2}$
Root number:	$-1$
$\Aut(K/\Q_{2})$:	$C_2^2$
This field is not Galois over $\Q_{2}.$
Visible Artin slopes:	$[2, 2, 3]$
Visible Swan slopes:	$[1,1,2]$
Means:	$\langle\frac{1}{2}, \frac{3}{4}, \frac{11}{8}\rangle$
Rams:	$(1, 1, 5)$
Jump set:	$[1, 3, 7, 15]$
Roots of unity:	$6 = (2^{ 2 } - 1) \cdot 2$

Intermediate fields

$\Q_{2}(\sqrt{5})$, 2.2.2.4a2.1, 2.2.2.6a1.2, 2.2.2.6a1.3, 2.2.4.12a7.2, 2.2.4.16b5.2, 2.2.4.16b5.5

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:	\( x^{8} + \left(4 t + 4\right) x^{7} + \left(2 t + 2\right) x^{6} + \left(4 t + 4\right) x^{5} + 2 t x^{4} + 4 t x^{3} + 8 t + 6 \) $\ \in\Q_{2}(t)[x]$

Ramification polygon

Residual polynomials:	$z^6 + t z^2 + (t + 1)$,$(t + 1) z + t$
Associated inertia:	$2$,$1$
Indices of inseparability:	$[11, 6, 4, 0]$

Invariants of the Galois closure

Galois degree:	$128$
Galois group:	$C_2^5:C_4$ (as 16T227)
Inertia group:	Intransitive group isomorphic to $C_2^5$
Wild inertia group:	$C_2^5$
Galois unramified degree:	$4$
Galois tame degree:	$1$
Galois Artin slopes:	$[2, 2, 2, 2, 3]$
Galois Swan slopes:	$[1,1,1,1,2]$
Galois mean slope:	$2.4375$
Galois splitting model:	$x^{16} - 12 x^{14} + 48 x^{12} - 144 x^{10} + 380 x^{8} - 624 x^{6} + 528 x^{4} - 192 x^{2} + 16$