Properties

Label 2.61.ay_kb
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:  $1 - 24 x + 261 x^{2} - 1464 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.135025069903$, $\pm0.285069722533$
Angle rank:  $2$ (numerical)
Number field:  4.0.153625.1
Galois group:  $D_{4}$
Jacobians:  $28$
Isomorphism classes:  28

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2495$ $13650145$ $51651330320$ $191813489207545$ $713379988161809375$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $38$ $3668$ $227558$ $13853508$ $844640198$ $51520471238$ $3142742783918$ $191707322200708$ $11694146305804958$ $713342913935332148$

Jacobians and polarizations

This isogeny class contains the Jacobians of 28 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 4.0.153625.1.

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.y_kb$2$(not in LMFDB)