Properties

Label 2.23.g_be
Base field $\F_{23}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{23}$
Dimension:  $2$
L-polynomial:  $( 1 - 2 x + 23 x^{2} )( 1 + 8 x + 23 x^{2} )$
  $1 + 6 x + 30 x^{2} + 138 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.433137181604$, $\pm0.813988011405$
Angle rank:  $2$ (numerical)
Jacobians:  $28$

This isogeny class is not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $704$ $292864$ $149150144$ $78318862336$ $41366340323264$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $30$ $554$ $12258$ $279870$ $6426990$ $148066058$ $3404873586$ $78311067454$ $1801151509374$ $41426493059114$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 28 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{23}$
The isogeny class factors as 1.23.ac $\times$ 1.23.i and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:

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_ck$2$(not in LMFDB)
2.23.ag_be$2$(not in LMFDB)
2.23.k_ck$2$(not in LMFDB)