Properties

Label 2.89.s_jj
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:  $( 1 + 5 x + 89 x^{2} )( 1 + 13 x + 89 x^{2} )$
  $1 + 18 x + 243 x^{2} + 1602 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.585371785029$, $\pm0.741949407251$
Angle rank:  $2$ (numerical)
Jacobians:  $72$
Isomorphism classes:  204

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $9785$ $64042825$ $495233096960$ $3937102921854025$ $31182021567541116425$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $108$ $8084$ $702486$ $62750436$ $5584113468$ $496981023662$ $44231333129532$ $3936588751002436$ $350356405121554374$ $31181719922751364724$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 72 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.f $\times$ 1.89.n 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.as_jj$2$(not in LMFDB)
2.89.ai_ej$2$(not in LMFDB)
2.89.i_ej$2$(not in LMFDB)