Properties

Label 2.23.a_ay
Base field $\F_{23}$
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:  $\F_{23}$
Dimension:  $2$
L-polynomial:  $1 - 24 x^{2} + 529 x^{4}$
Frobenius angles:  $\pm0.162641718363$, $\pm0.837358281637$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-22}, \sqrt{70})\)
Galois group:  $C_2^2$
Jacobians:  $4$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $506$ $256036$ $148060154$ $78581544976$ $41426506234586$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $24$ $482$ $12168$ $280806$ $6436344$ $148084418$ $3404825448$ $78311639998$ $1801152661464$ $41426501255522$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 4 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{23^{2}}$.

Endomorphism algebra over $\F_{23}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-22}, \sqrt{70})\).
Endomorphism algebra over $\overline{\F}_{23}$
The base change of $A$ to $\F_{23^{2}}$ is 1.529.ay 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-385}) \)$)$

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.23.a_y$4$(not in LMFDB)