Properties

Label 2.61.f_bk
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:  $1 + 5 x + 36 x^{2} + 305 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.349699683640$, $\pm0.782211468955$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-582 -30 \sqrt{41}})\)
Galois group:  $D_{4}$
Jacobians:  $144$
Cyclic group of points:    no
Non-cyclic primes:   $2, 3$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4068$ $14026464$ $51633903600$ $191834281436544$ $713261179830318228$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $67$ $3769$ $227482$ $13855009$ $844499527$ $51520200838$ $3142742531107$ $191707316174689$ $11694146500948642$ $713342910246605329$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 144 curves (of which all are hyperelliptic):

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 \(\Q(\sqrt{-582 -30 \sqrt{41}})\).

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.af_bk$2$(not in LMFDB)