Properties

Label 2.163.abt_bfx
Base field $\F_{163}$
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:  $\F_{163}$
Dimension:  $2$
L-polynomial:  $1 - 45 x + 829 x^{2} - 7335 x^{3} + 26569 x^{4}$
Frobenius angles:  $\pm0.0992622747912$, $\pm0.199159696144$
Angle rank:  $2$ (numerical)
Number field:  4.0.2319525.8
Galois group:  $D_{4}$
Jacobians:  $16$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $20019$ $696240801$ $18750113281701$ $498329605649727981$ $13239713117398182381264$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $119$ $26203$ $4329533$ $705937531$ $115064287544$ $18755379226807$ $3057125340863783$ $498311415036903523$ $81224760536549909129$ $13239635967018178444678$

Jacobians and polarizations

This isogeny class contains the Jacobians of 16 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{163}$.

Endomorphism algebra over $\F_{163}$
The endomorphism algebra of this simple isogeny class is 4.0.2319525.8.

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.163.bt_bfx$2$(not in LMFDB)