Properties

Label 2.67.ac_acl
Base field $\F_{67}$
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:  $\F_{67}$
Dimension:  $2$
L-polynomial:  $1 - 2 x - 63 x^{2} - 134 x^{3} + 4489 x^{4}$
Frobenius angles:  $\pm0.127681533513$, $\pm0.794348200180$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{22})\)
Galois group:  $C_2^2$
Jacobians:  $40$
Cyclic group of points:    yes

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4291$ $19579833$ $90222136900$ $406227357352089$ $1822780773001210771$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $66$ $4360$ $299976$ $20159044$ $1350082866$ $90459274750$ $6060715328118$ $406067700012484$ $27206534984972712$ $1822837803635897800$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 40 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{67^{3}}$.

Endomorphism algebra over $\F_{67}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-3}, \sqrt{22})\).
Endomorphism algebra over $\overline{\F}_{67}$
The base change of $A$ to $\F_{67^{3}}$ is 1.300763.ape 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-66}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.67.c_acl$2$(not in LMFDB)
2.67.e_fi$3$(not in LMFDB)
2.67.ae_fi$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.67.c_acl$2$(not in LMFDB)
2.67.e_fi$3$(not in LMFDB)
2.67.ae_fi$6$(not in LMFDB)
2.67.a_fa$6$(not in LMFDB)
2.67.a_afa$12$(not in LMFDB)