Properties

Label 2.61.ad_aca
Base field $\F_{61}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{61}$
Dimension:  $2$
L-polynomial:  $1 - 3 x - 52 x^{2} - 183 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.105151362908$, $\pm0.771818029575$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{-235})\)
Galois group:  $C_2^2$
Jacobians:  $26$
Isomorphism classes:  88

This isogeny class is simple but not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $3484$ $13434304$ $51284131600$ $191781084328704$ $713302521976375084$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $59$ $3609$ $225938$ $13851169$ $844548479$ $51520737318$ $3142746297659$ $191707313682529$ $11694146519265338$ $713342912260729329$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 26 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{61^{3}}$.

Endomorphism algebra over $\F_{61}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-3}, \sqrt{-235})\).
Endomorphism algebra over $\overline{\F}_{61}$
The base change of $A$ to $\F_{61^{3}}$ is 1.226981.auc 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-235}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.61.d_aca$2$(not in LMFDB)
2.61.g_fb$3$(not in LMFDB)
2.61.ag_fb$6$(not in LMFDB)

Below is a list of all twists of this isogeny class.

TwistExtension degreeCommon base change
2.61.d_aca$2$(not in LMFDB)
2.61.g_fb$3$(not in LMFDB)
2.61.ag_fb$6$(not in LMFDB)
2.61.a_ej$6$(not in LMFDB)
2.61.a_aej$12$(not in LMFDB)