Properties

Label 2.23.al_cl
Base field $\F_{23}$
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:  $\F_{23}$
Dimension:  $2$
L-polynomial:  $1 - 11 x + 63 x^{2} - 253 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.0980658819420$, $\pm0.437882154474$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-194 -22 \sqrt{53}})\)
Galois group:  $D_{4}$
Jacobians:  $10$
Isomorphism classes:  10
Cyclic group of points:    yes

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $329$ $281953$ $147910175$ $78003143309$ $41398488019504$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $13$ $535$ $12157$ $278739$ $6431988$ $148052035$ $3405004231$ $78311416179$ $1801152527011$ $41426519279550$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 10 curves (of which all are hyperelliptic):

  • $y^2=7 x^6+17 x^5+19 x^4+3 x^3+11 x^2+x+11$
  • $y^2=21 x^6+10 x^5+21 x^4+19 x^3+22 x^2+13 x+9$
  • $y^2=11 x^6+11 x^5+11 x^4+22 x^3+15 x^2+8 x+3$
  • $y^2=18 x^6+19 x^5+7 x^4+9 x^3+13 x^2+2 x$
  • $y^2=19 x^6+12 x^5+22 x^4+11 x^3+2 x^2+21 x+10$
  • $y^2=17 x^6+x^5+9 x^4+5 x^3+21 x^2+21 x+7$
  • $y^2=10 x^6+19 x^5+2 x^4+16 x^3+8 x^2+18 x+4$
  • $y^2=5 x^6+3 x^5+11 x^4+3 x^3+6 x^2+21 x+7$
  • $y^2=8 x^5+8 x^4+2 x^3+3 x^2+12 x+12$
  • $y^2=19 x^6+21 x^5+20 x^4+5 x^3+12 x^2+5 x+17$

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{23}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-194 -22 \sqrt{53}})\).

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.l_cl$2$(not in LMFDB)