Properties

Label 2.23.g_bu
Base field $\F_{23}$
Dimension $2$
$p$-rank $1$
Ordinary no
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:  $( 1 + 23 x^{2} )( 1 + 6 x + 23 x^{2} )$
  $1 + 6 x + 46 x^{2} + 138 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.5$, $\pm0.715122617226$
Angle rank:  $1$ (numerical)
Jacobians:  $72$

This isogeny class is not simple, primitive, not ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

$p$-rank:  $1$
Slopes:  $[0, 1/2, 1/2, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $720$ $311040$ $145650960$ $78282547200$ $41418839091600$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $30$ $586$ $11970$ $279742$ $6435150$ $148045354$ $3404942130$ $78310067518$ $1801152126270$ $41426535533386$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 72 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{23^{2}}$.

Endomorphism algebra over $\F_{23}$
The isogeny class factors as 1.23.a $\times$ 1.23.g and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{23}$
The base change of $A$ to $\F_{23^{2}}$ is 1.529.k $\times$ 1.529.bu. 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.ag_bu$2$(not in LMFDB)