Properties

Label 2.169.abt_bgg
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:  $( 1 - 25 x + 169 x^{2} )( 1 - 20 x + 169 x^{2} )$
  $1 - 45 x + 838 x^{2} - 7605 x^{3} + 28561 x^{4}$
Frobenius angles:  $\pm0.0885687144757$, $\pm0.220639651288$
Angle rank:  $2$ (numerical)
Jacobians:  $32$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $21750$ $805837500$ $23294178747000$ $665439475217400000$ $19005042530173093293750$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $125$ $28213$ $4826000$ $815758753$ $137859063125$ $23298091147618$ $3937376414412125$ $665416608970146433$ $112455406947814508000$ $19004963774919168805573$

Jacobians and polarizations

This isogeny class contains the Jacobians of 32 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.au 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.af_agg$2$(not in LMFDB)
2.169.f_agg$2$(not in LMFDB)
2.169.bt_bgg$2$(not in LMFDB)