Properties

Label 2.89.b_cu
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:  $1 + x + 72 x^{2} + 89 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.326002566082$, $\pm0.694146852346$
Angle rank:  $2$ (numerical)
Number field:  4.0.1122476.1
Galois group:  $D_{4}$
Jacobians:  $350$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $8084$ $63895936$ $497016640016$ $3937922126288384$ $31181465089430547124$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $91$ $8065$ $705022$ $62763489$ $5584013811$ $496978669486$ $44231338500139$ $3936588826608129$ $350356404021865198$ $31181719948590469425$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 350 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 4.0.1122476.1.

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.ab_cu$2$(not in LMFDB)