Properties

Label 2.169.abs_bfh
Base field $\F_{13^{2}}$
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:  $\F_{13^{2}}$
Dimension:  $2$
L-polynomial:  $( 1 - 25 x + 169 x^{2} )( 1 - 19 x + 169 x^{2} )$
  $1 - 44 x + 813 x^{2} - 7436 x^{3} + 28561 x^{4}$
Frobenius angles:  $\pm0.0885687144757$, $\pm0.239161554446$
Angle rank:  $2$ (numerical)
Jacobians:  $84$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $21895$ $806940225$ $23297237074240$ $665442179281049625$ $19005029097392428768975$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $126$ $28252$ $4826634$ $815762068$ $137858965686$ $23298088032142$ $3937376366611254$ $665416608605924068$ $112455406950179714106$ $19004963775046849071052$

Jacobians and polarizations

This isogeny class contains the Jacobians of 84 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{13^{2}}$.

Endomorphism algebra over $\F_{13^{2}}$
The isogeny class factors as 1.169.az $\times$ 1.169.at and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.169.ag_afh$2$(not in LMFDB)
2.169.g_afh$2$(not in LMFDB)
2.169.bs_bfh$2$(not in LMFDB)