Properties

Label 2.89.b_t
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:  $1 + x + 19 x^{2} + 89 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.277968510535$, $\pm0.744741055041$
Angle rank:  $2$ (numerical)
Number field:  4.0.6498557.1
Galois group:  $D_{4}$
Jacobians:  $189$
Isomorphism classes:  189

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $8031$ $63051381$ $497129637447$ $3938514161026293$ $31181463605572224816$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $91$ $7959$ $705181$ $62772923$ $5584013546$ $496980442071$ $44231332214657$ $3936588585573139$ $350356404417707623$ $31181719940401074414$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 189 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 4.0.6498557.1.

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_t$2$(not in LMFDB)