Properties

Label 2.7.af_t
Base field $\F_{7}$
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:  $\F_{7}$
Dimension:  $2$
L-polynomial:  $1 - 5 x + 19 x^{2} - 35 x^{3} + 49 x^{4}$
Frobenius angles:  $\pm0.260350433790$, $\pm0.415892662795$
Angle rank:  $2$ (numerical)
Number field:  4.0.9725.1
Galois group:  $D_{4}$
Jacobians:  $1$
Isomorphism classes:  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

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $29$ $3161$ $138011$ $5882621$ $280790064$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $3$ $63$ $399$ $2451$ $16708$ $117507$ $823749$ $5762643$ $40338813$ $282456478$

Jacobians and polarizations

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

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{7}$.

Endomorphism algebra over $\F_{7}$
The endomorphism algebra of this simple isogeny class is 4.0.9725.1.

Base change

This is a primitive isogeny class.

Twists

Below is a list of all twists of this isogeny class.

TwistExtension degreeCommon base change
2.7.f_t$2$2.49.n_ef