Properties

Label 2.61.r_gy
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:  $1 + 17 x + 180 x^{2} + 1037 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.597818699027$, $\pm0.787759329610$
Angle rank:  $2$ (numerical)
Number field:  4.0.4200957.1
Galois group:  $D_{4}$
Jacobians:  $80$
Isomorphism classes:  80
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4956$ $14114688$ $51258738384$ $191764465976832$ $713343785884258956$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $79$ $3793$ $225826$ $13849969$ $844597339$ $51520548454$ $3142739711575$ $191707318344385$ $11694146379941770$ $713342908411829593$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 80 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 4.0.4200957.1.

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.ar_gy$2$(not in LMFDB)