Properties

Label 2.23.c_bv
Base field $\F_{23}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
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:  $( 1 + x + 23 x^{2} )^{2}$
  $1 + 2 x + 47 x^{2} + 46 x^{3} + 529 x^{4}$
Frobenius angles:  $\pm0.533246515430$, $\pm0.533246515430$
Angle rank:  $1$ (numerical)
Jacobians:  $9$

This isogeny class is not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $625$ $330625$ $146410000$ $77771265625$ $41459111265625$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $26$ $620$ $12032$ $277908$ $6441406$ $148075310$ $3404669602$ $78310234468$ $1801156996736$ $41426524147100$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 9 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{23}$
The isogeny class factors as 1.23.b 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-91}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.23.ac_bv$2$(not in LMFDB)
2.23.a_bt$2$(not in LMFDB)
2.23.ab_aw$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.23.ac_bv$2$(not in LMFDB)
2.23.a_bt$2$(not in LMFDB)
2.23.ab_aw$3$(not in LMFDB)
2.23.a_abt$4$(not in LMFDB)
2.23.b_aw$6$(not in LMFDB)