Properties

Label 2.2.b_b
Base field $\F_{2}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple yes
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{2}$
Dimension:  $2$
L-polynomial:  $1 + x + x^{2} + 2 x^{3} + 4 x^{4}$
Frobenius angles:  $\pm0.347634004421$, $\pm0.802798946039$
Angle rank:  $2$ (numerical)
Number field:  4.0.2873.1
Galois group:  $D_{4}$
Jacobians:  1

This isogeny class is simple and geometrically simple, primitive, ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

This isogeny class is ordinary.

$p$-rank:  $2$
Slopes:  $[0, 0, 1, 1]$

Point counts

This isogeny class contains the Jacobian of 1 curve (which is hyperelliptic), and hence is principally polarizable:

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $9$ $27$ $108$ $459$ $549$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $4$ $6$ $13$ $26$ $14$ $63$ $116$ $274$ $589$ $966$

Decomposition and endomorphism algebra

Endomorphism algebra over $\F_{2}$
The endomorphism algebra of this simple isogeny class is 4.0.2873.1.
All geometric endomorphisms are defined over $\F_{2}$.

Base change

This is a primitive isogeny class.

Twists

Below is a list of all twists of this isogeny class.
TwistExtension degreeCommon base change
2.2.ab_b$2$2.4.b_f