Properties

Label 2.23.am_dc
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

Related objects

Downloads

Learn more

Invariants

Base field:  $\F_{23}$
Dimension:  $2$
L-polynomial:  $1 - 12 x + 80 x^{2} - 276 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.218762671529$, $\pm0.341325181820$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\sqrt{-54 +12 \sqrt{2}})\)
Galois group:  $D_{4}$
Jacobians:  $8$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $322$ $289156$ $152025538$ $78707106576$ $41438017377442$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $12$ $546$ $12492$ $281254$ $6438132$ $148025346$ $3404774196$ $78310960318$ $1801152606060$ $41426503978146$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 8 curves (of which all are hyperelliptic):

  • $y^2=11 x^6+13 x^5+5 x^4+12 x^3+17 x^2+19 x$
  • $y^2=17 x^6+16 x^5+19 x^4+17 x^3+5 x^2+18 x+14$
  • $y^2=7 x^6+16 x^5+2 x^4+18 x^3+8 x^2+22 x+21$
  • $y^2=12 x^6+22 x^5+20 x^4+9 x^3+15 x^2+7$
  • $y^2=17 x^6+15 x^5+15 x^4+19 x^3+17 x^2+6 x+5$
  • $y^2=2 x^6+6 x^5+14 x^4+6 x^3+11 x^2+2 x+3$
  • $y^2=5 x^6+18 x^5+17 x^4+5 x^3+6 x^2+19 x+6$
  • $y^2=7 x^6+6 x^5+5 x^4+16 x^3+x^2+19 x+17$

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 \(\Q(\sqrt{-54 +12 \sqrt{2}})\).

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.m_dc$2$(not in LMFDB)