Properties

Label 2.197.aby_bnb
Base field $\F_{197}$
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:  $\F_{197}$
Dimension:  $2$
L-polynomial:  $( 1 - 27 x + 197 x^{2} )( 1 - 23 x + 197 x^{2} )$
  $1 - 50 x + 1015 x^{2} - 9850 x^{3} + 38809 x^{4}$
Frobenius angles:  $\pm0.0882242067266$, $\pm0.194339516027$
Angle rank:  $2$ (numerical)
Jacobians:  $72$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $29925$ $1488020625$ $58434153926400$ $2268490456054265625$ $88036659801248398057125$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $148$ $38340$ $7643074$ $1506163268$ $296710165508$ $58451742974070$ $11514990645526964$ $2268453125248368388$ $446885265421874979418$ $88036397287305461777700$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 72 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{197}$.

Endomorphism algebra over $\F_{197}$
The isogeny class factors as 1.197.abb $\times$ 1.197.ax 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
2.197.ae_ait$2$(not in LMFDB)
2.197.e_ait$2$(not in LMFDB)
2.197.by_bnb$2$(not in LMFDB)