Properties

Label 2.256.acd_bwd
Base field $\F_{2^{8}}$
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:  $\F_{2^{8}}$
Dimension:  $2$
L-polynomial:  $1 - 55 x + 1251 x^{2} - 14080 x^{3} + 65536 x^{4}$
Frobenius angles:  $\pm0.0468977989438$, $\pm0.239713717685$
Angle rank:  $2$ (numerical)
Number field:  4.0.50319009.1
Galois group:  $D_{4}$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $52653$ $4260838719$ $281438061848100$ $18446834335464510699$ $1208925983194026518273403$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $202$ $65014$ $16775017$ $4294988314$ $1099511776552$ $281474961900343$ $72057593477341702$ $18446744062122393394$ $4722366482715365551897$ $1208925819613716882793654$

Jacobians and polarizations

This isogeny class contains a Jacobian, and hence is principally polarizable.

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{2^{8}}$.

Endomorphism algebra over $\F_{2^{8}}$
The endomorphism algebra of this simple isogeny class is 4.0.50319009.1.

Base change

This is a primitive isogeny class.

Twists

Below is a list of all twists of this isogeny class.

TwistExtension degreeCommon base change
2.256.cd_bwd$2$(not in LMFDB)