Properties

Label 2.89.ae_de
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:  $( 1 - 12 x + 89 x^{2} )( 1 + 8 x + 89 x^{2} )$
  $1 - 4 x + 82 x^{2} - 356 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.280588346245$, $\pm0.639374052381$
Angle rank:  $2$ (numerical)
Jacobians:  $600$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $7644$ $63934416$ $496875968316$ $3937688969969664$ $31182650451928299324$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $86$ $8070$ $704822$ $62759774$ $5584226086$ $496979294886$ $44231320660774$ $3936588832892734$ $350356402952970998$ $31181719935461838150$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 600 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.am $\times$ 1.89.i 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.au_ko$2$(not in LMFDB)
2.89.e_de$2$(not in LMFDB)
2.89.u_ko$2$(not in LMFDB)