Properties

Label 2.89.h_cg
Base field $\F_{89}$
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:  $\F_{89}$
Dimension:  $2$
L-polynomial:  $( 1 - 8 x + 89 x^{2} )( 1 + 15 x + 89 x^{2} )$
  $1 + 7 x + 58 x^{2} + 623 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.360625947619$, $\pm0.792528363707$
Angle rank:  $2$ (numerical)
Jacobians:  $240$
Cyclic group of points:    yes

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $8610$ $63283500$ $497682417960$ $3937622899392000$ $31180211185432744050$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $97$ $7989$ $705964$ $62758721$ $5583789257$ $496981076562$ $44231333927633$ $3936588862712641$ $350356405638319276$ $31181719915444994949$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 240 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{89}$.

Endomorphism algebra over $\F_{89}$
The isogeny class factors as 1.89.ai $\times$ 1.89.p 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
2.89.ax_lm$2$(not in LMFDB)
2.89.ah_cg$2$(not in LMFDB)
2.89.x_lm$2$(not in LMFDB)