Properties

Label 2.169.aby_blb
Base field $\F_{13^{2}}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
Geometrically simple no
Primitive no
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{13^{2}}$
Dimension:  $2$
L-polynomial:  $( 1 - 25 x + 169 x^{2} )^{2}$
  $1 - 50 x + 963 x^{2} - 8450 x^{3} + 28561 x^{4}$
Frobenius angles:  $\pm0.0885687144757$, $\pm0.0885687144757$
Angle rank:  $1$ (numerical)
Jacobians:  $6$

This isogeny class is not simple, not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $21025$ $799475625$ $23269625299600$ $665375421944975625$ $19004927208209142600625$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $120$ $27988$ $4820910$ $815680228$ $137858226600$ $23298087024718$ $3937376478082440$ $665416611171280708$ $112455406986047162430$ $19004963775397054624948$

Jacobians and polarizations

This isogeny class contains the Jacobians of 6 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 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-51}) \)$)$

Base change

This isogeny class is not primitive. It is a base change from the following isogeny classes over subfields of $\F_{13^{2}}$.

SubfieldPrimitive Model
$\F_{13}$2.13.a_az

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.169.a_alb$2$(not in LMFDB)
2.169.by_blb$2$(not in LMFDB)
2.169.z_ro$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.169.a_alb$2$(not in LMFDB)
2.169.by_blb$2$(not in LMFDB)
2.169.z_ro$3$(not in LMFDB)
2.169.a_lb$4$(not in LMFDB)
2.169.az_ro$6$(not in LMFDB)