Properties

Label 2.61.abb_lp
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:  $1 - 27 x + 301 x^{2} - 1647 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.0643104250482$, $\pm0.230612073966$
Angle rank:  $2$ (numerical)
Number field:  4.0.2197.1
Galois group:  $C_4$
Jacobians:  $9$
Isomorphism classes:  9

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2349$ $13382253$ $51465248721$ $191736116755173$ $713360334091993344$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $35$ $3595$ $226739$ $13847923$ $844616930$ $51520377283$ $3142741037471$ $191707289788099$ $11694145935604151$ $713342911430554390$

Jacobians and polarizations

This isogeny class contains the Jacobians of 9 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 4.0.2197.1.

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_lp$2$(not in LMFDB)