Properties

Label 2.7.ac_d
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:  $1 - 2 x + 3 x^{2} - 14 x^{3} + 49 x^{4}$
Frobenius angles:  $\pm0.180410678678$, $\pm0.654187137638$
Angle rank:  $2$ (numerical)
Number field:  4.0.25488.1
Galois group:  $D_{4}$
Jacobians:  $6$
Isomorphism classes:  6

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $37$ $2553$ $107152$ $6007209$ $289576837$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $6$ $52$ $312$ $2500$ $17226$ $117646$ $825222$ $5769220$ $40336872$ $282452212$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 6 curves (of which all are hyperelliptic):

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 4.0.25488.1.

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.c_d$2$2.49.c_bz