Properties

Label 2.61.e_abt
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:  $1 + 4 x - 45 x^{2} + 244 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.249095665427$, $\pm0.915762332094$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{19})\)
Galois group:  $C_2^2$
Jacobians:  $32$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $3925$ $13458825$ $51824522500$ $191759844670425$ $713390147149373125$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $66$ $3616$ $228318$ $13849636$ $844652226$ $51520389838$ $3142739393706$ $191707299700036$ $11694145779249558$ $713342913101183776$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 32 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 \(\Q(\sqrt{-3}, \sqrt{19})\).
Endomorphism algebra over $\overline{\F}_{61}$
The base change of $A$ to $\F_{61^{3}}$ is 1.226981.zs 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-57}) \)$)$

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.ae_abt$2$(not in LMFDB)
2.61.ai_fi$3$(not in LMFDB)
2.61.a_ec$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.61.ae_abt$2$(not in LMFDB)
2.61.ai_fi$3$(not in LMFDB)
2.61.a_ec$6$(not in LMFDB)
2.61.i_fi$6$(not in LMFDB)
2.61.a_aec$12$(not in LMFDB)