Properties

Label 2.89.r_jl
Base field $\F_{89}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple yes
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{89}$
Dimension:  $2$
L-polynomial:  $1 + 17 x + 245 x^{2} + 1513 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.606732206369$, $\pm0.693807873504$
Angle rank:  $2$ (numerical)
Number field:  4.0.33535845.1
Galois group:  $D_{4}$
Jacobians:  $32$
Isomorphism classes:  32
Cyclic group of points:    yes

This isogeny class is simple and geometrically 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $9697$ $64358989$ $494839781521$ $3937118996937205$ $31182630882077508352$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $107$ $8123$ $701927$ $62750691$ $5584222582$ $496979459651$ $44231337380743$ $3936588898381411$ $350356403001664403$ $31181719930004388878$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 32 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{89}$
The endomorphism algebra of this simple isogeny class is 4.0.33535845.1.

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.ar_jl$2$(not in LMFDB)