Properties

Label 2.27.an_dq
Base field $\F_{3^{3}}$
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:  $\F_{3^{3}}$
Dimension:  $2$
L-polynomial:  $( 1 - 8 x + 27 x^{2} )( 1 - 5 x + 27 x^{2} )$
  $1 - 13 x + 94 x^{2} - 351 x^{3} + 729 x^{4}$
Frobenius angles:  $\pm0.220355751984$, $\pm0.340228233311$
Angle rank:  $2$ (numerical)
Jacobians:  $12$
Isomorphism classes:  60

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $460$ $546480$ $395686480$ $283481035200$ $205930114591300$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $15$ $749$ $20100$ $533417$ $14351625$ $387402326$ $10460251635$ $282429437393$ $7625597388060$ $205891117739789$

Jacobians and polarizations

This isogeny class contains the Jacobians of 12 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{3^{3}}$.

Endomorphism algebra over $\F_{3^{3}}$
The isogeny class factors as 1.27.ai $\times$ 1.27.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
2.27.ad_o$2$2.729.t_bsy
2.27.d_o$2$2.729.t_bsy
2.27.n_dq$2$2.729.t_bsy