Properties

Label 2.131.abm_xz
Base field $\F_{131}$
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:  $\F_{131}$
Dimension:  $2$
L-polynomial:  $( 1 - 19 x + 131 x^{2} )^{2}$
  $1 - 38 x + 623 x^{2} - 4978 x^{3} + 17161 x^{4}$
Frobenius angles:  $\pm0.188329584469$, $\pm0.188329584469$
Angle rank:  $1$ (numerical)
Jacobians:  $7$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $12769$ $291145969$ $5056651690000$ $86744647524460249$ $1488406824690880065409$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $94$ $16964$ $2249308$ $294548964$ $38580262154$ $5053921397318$ $662062677510734$ $86730203444447044$ $11361656646688293028$ $1488377021587554390404$

Jacobians and polarizations

This isogeny class contains the Jacobians of 7 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{131}$.

Endomorphism algebra over $\F_{131}$
The isogeny class factors as 1.131.at 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-163}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.131.a_adv$2$(not in LMFDB)
2.131.bm_xz$2$(not in LMFDB)
2.131.t_iw$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.131.a_adv$2$(not in LMFDB)
2.131.bm_xz$2$(not in LMFDB)
2.131.t_iw$3$(not in LMFDB)
2.131.a_dv$4$(not in LMFDB)
2.131.at_iw$6$(not in LMFDB)