Properties

Label 2.23.e_o
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:  $( 1 - 4 x + 23 x^{2} )( 1 + 8 x + 23 x^{2} )$
  $1 + 4 x + 14 x^{2} + 92 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.363071407864$, $\pm0.813988011405$
Angle rank:  $2$ (numerical)
Jacobians:  $82$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $640$ $286720$ $150144640$ $78561280000$ $41367356483200$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $28$ $542$ $12340$ $280734$ $6427148$ $148038014$ $3404772644$ $78311540926$ $1801155847420$ $41426494425182$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 82 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.ae $\times$ 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.am_da$2$(not in LMFDB)
2.23.ae_o$2$(not in LMFDB)
2.23.m_da$2$(not in LMFDB)