Properties

Label 2.27.am_cw
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:  $( 1 - 10 x + 27 x^{2} )( 1 - 2 x + 27 x^{2} )$
  $1 - 12 x + 74 x^{2} - 324 x^{3} + 729 x^{4}$
Frobenius angles:  $\pm0.0877398280459$, $\pm0.438356648427$
Angle rank:  $2$ (numerical)
Jacobians:  $48$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $468$ $533520$ $386721972$ $281527833600$ $205780798043028$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $16$ $734$ $19648$ $529742$ $14341216$ $387439406$ $10460624848$ $282430143518$ $7625596404016$ $205891148425214$

Jacobians and polarizations

This isogeny class contains the Jacobians of 48 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.ak $\times$ 1.27.ac 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.ai_bi$2$2.729.e_abgk
2.27.i_bi$2$2.729.e_abgk
2.27.m_cw$2$2.729.e_abgk