Properties

Label 2.89.i_gw
Base field $\F_{89}$
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:  $\F_{89}$
Dimension:  $2$
L-polynomial:  $( 1 + 89 x^{2} )( 1 + 8 x + 89 x^{2} )$
  $1 + 8 x + 178 x^{2} + 712 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.5$, $\pm0.639374052381$
Angle rank:  $1$ (numerical)
Jacobians:  $384$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $8820$ $65091600$ $495837829620$ $3935773487923200$ $31182399900885410100$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $98$ $8214$ $703346$ $62729246$ $5584181218$ $496981473462$ $44231333877682$ $3936588797602366$ $350356402858995554$ $31181719937474975574$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 384 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{89^{2}}$.

Endomorphism algebra over $\F_{89}$
The isogeny class factors as 1.89.a $\times$ 1.89.i 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 $\overline{\F}_{89}$
The base change of $A$ to $\F_{89^{2}}$ is 1.7921.ek $\times$ 1.7921.gw. 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.ai_gw$2$(not in LMFDB)