Properties

Label 2.23.al_cq
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:  $1 - 11 x + 68 x^{2} - 253 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.162255762163$, $\pm0.411666868096$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-214 -22 \sqrt{33}})\)
Galois group:  $D_{4}$
Jacobians:  $6$
Isomorphism classes:  6
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $334$ $287908$ $149932600$ $78313279264$ $41421476307754$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $13$ $545$ $12322$ $279849$ $6435563$ $148057850$ $3405040421$ $78311655409$ $1801151383726$ $41426494361225$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 6 curves (of which all are hyperelliptic):

  • $y^2=19 x^6+9 x^5+17 x^4+18 x^3+15 x^2+18 x+11$
  • $y^2=14 x^6+20 x^4+5 x^3+9 x^2+5 x+13$
  • $y^2=5 x^6+4 x^5+17 x^4+22 x^3+6 x^2+7 x+22$
  • $y^2=17 x^6+6 x^5+17 x^4+5 x^3+x+21$
  • $y^2=10 x^6+4 x^5+14 x^4+2 x^3+14 x^2+16 x+14$
  • $y^2=6 x^6+22 x^5+18 x^4+13 x^3+11 x^2+7 x+22$

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 \(\Q(\sqrt{-214 -22 \sqrt{33}})\).

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_cq$2$(not in LMFDB)