Properties

Label 2.61.ax_jk
Base field $\F_{61}$
Dimension $2$
$p$-rank $1$
Ordinary no
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:  $1 - 23 x + 244 x^{2} - 1403 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.109726878648$, $\pm0.321721348102$
Angle rank:  $2$ (numerical)
Number field:  4.0.512705.1
Galois group:  $D_{4}$
Jacobians:  $20$
Isomorphism classes:  20

This isogeny class is simple and geometrically simple, primitive, not ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

$p$-rank:  $1$
Slopes:  $[0, 1/2, 1/2, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2540$ $13695680$ $51624778640$ $191751626981120$ $713333957925433500$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $39$ $3681$ $227442$ $13849041$ $844585699$ $51520147878$ $3142742990559$ $191707345034241$ $11694146513673882$ $713342914584741001$

Jacobians and polarizations

This isogeny class contains the Jacobians of 20 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 4.0.512705.1.

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.x_jk$2$(not in LMFDB)