Properties

Label 2.89.au_jt
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

Related objects

Downloads

Learn more

Invariants

Base field:  $\F_{89}$
Dimension:  $2$
L-polynomial:  $( 1 - 15 x + 89 x^{2} )( 1 - 5 x + 89 x^{2} )$
  $1 - 20 x + 253 x^{2} - 1780 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.207471636293$, $\pm0.414628214971$
Angle rank:  $2$ (numerical)
Jacobians:  $165$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6375$ $63590625$ $498280608000$ $3936969422465625$ $31181736113307159375$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $70$ $8028$ $706810$ $62748308$ $5584062350$ $496982249838$ $44231349562190$ $3936588813552868$ $350356401837664330$ $31181719909094915148$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 165 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.ap $\times$ 1.89.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
2.89.ak_dz$2$(not in LMFDB)
2.89.k_dz$2$(not in LMFDB)
2.89.u_jt$2$(not in LMFDB)