Properties

Label 2.23.k_cn
Base field $\F_{23}$
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:  $\F_{23}$
Dimension:  $2$
L-polynomial:  $1 + 10 x + 65 x^{2} + 230 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.585672095708$, $\pm0.783089164485$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-61 -10 \sqrt{6}})\)
Galois group:  $D_{4}$
Jacobians:  $12$
Isomorphism classes:  12
Cyclic group of points:    yes

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $835$ $296425$ $144912580$ $78441465625$ $41426821687675$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $34$ $560$ $11908$ $280308$ $6436394$ $148049030$ $3404721158$ $78310916068$ $1801157083804$ $41426488524800$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 12 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{23}$.

Endomorphism algebra over $\F_{23}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-61 -10 \sqrt{6}})\).

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.23.ak_cn$2$(not in LMFDB)