Properties

Label 2.23.ak_cg
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:  $1 - 10 x + 58 x^{2} - 230 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.145604305875$, $\pm0.453559101412$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-54 +10 \sqrt{13}})\)
Galois group:  $D_{4}$
Jacobians:  $30$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $348$ $288144$ $148664556$ $78140042496$ $41426191001868$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $14$ $546$ $12218$ $279230$ $6436294$ $148073922$ $3405041458$ $78311251774$ $1801151571614$ $41426514421986$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 30 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 \(\Q(\sqrt{-54 +10 \sqrt{13}})\).

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.k_cg$2$(not in LMFDB)