Properties

Label 2.61.ax_jj
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:  $1 - 23 x + 243 x^{2} - 1403 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.100123618576$, $\pm0.325377247674$
Angle rank:  $2$ (numerical)
Number field:  4.0.103725.1
Galois group:  $D_{4}$
Jacobians:  $24$
Isomorphism classes:  30

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2539$ $13687749$ $51609046975$ $191735811639909$ $713323953851741584$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $39$ $3679$ $227373$ $13847899$ $844573854$ $51520066783$ $3142742647629$ $191707344257299$ $11694146509589703$ $713342914532262454$

Jacobians and polarizations

This isogeny class contains the Jacobians of 24 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 4.0.103725.1.

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_jj$2$(not in LMFDB)