Properties

Label 2.23.an_di
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:  $( 1 - 8 x + 23 x^{2} )( 1 - 5 x + 23 x^{2} )$
  $1 - 13 x + 86 x^{2} - 299 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.186011988595$, $\pm0.325452467839$
Angle rank:  $2$ (numerical)
Jacobians:  $4$
Isomorphism classes:  10

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $304$ $282112$ $151232704$ $78690064384$ $41445675302224$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $11$ $533$ $12428$ $281193$ $6439321$ $148034558$ $3404818519$ $78311185201$ $1801153883204$ $41426508536093$

Jacobians and polarizations

This isogeny class contains the Jacobians of 4 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{23}$
The isogeny class factors as 1.23.ai $\times$ 1.23.af 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.ad_g$2$(not in LMFDB)
2.23.d_g$2$(not in LMFDB)
2.23.n_di$2$(not in LMFDB)