Properties

Label 2.61.abb_lr
Base field $\F_{61}$
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:  $\F_{61}$
Dimension:  $2$
L-polynomial:  $1 - 27 x + 303 x^{2} - 1647 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.114657586013$, $\pm0.208688212581$
Angle rank:  $2$ (numerical)
Number field:  4.0.68725.1
Galois group:  $D_{4}$
Jacobians:  $5$
Isomorphism classes:  5

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2351$ $13398349$ $51502277891$ $191783445050389$ $713402752074698576$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $35$ $3599$ $226901$ $13851339$ $844667150$ $51520945943$ $3142746156725$ $191707325699539$ $11694146107390571$ $713342911549467254$

Jacobians and polarizations

This isogeny class contains the Jacobians of 5 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{61}$.

Endomorphism algebra over $\F_{61}$
The endomorphism algebra of this simple isogeny class is 4.0.68725.1.

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.61.bb_lr$2$(not in LMFDB)