Properties

Label 2.83.abd_oc
Base field $\F_{83}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple yes
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{83}$
Dimension:  $2$
L-polynomial:  $1 - 29 x + 366 x^{2} - 2407 x^{3} + 6889 x^{4}$
Frobenius angles:  $\pm0.0761778611858$, $\pm0.287099181260$
Angle rank:  $2$ (numerical)
Number field:  4.0.1601993.1
Galois group:  $D_{4}$
Jacobians:  $20$
Isomorphism classes:  20

This isogeny class is simple and geometrically 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4820$ $46715440$ $327072610160$ $2252499859582400$ $15515959974845775100$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $55$ $6781$ $572020$ $47462697$ $3939020025$ $326939483494$ $27136041662155$ $2252292207567633$ $186940255968937420$ $15516041200218630861$

Jacobians and polarizations

This isogeny class contains the Jacobians of 20 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{83}$.

Endomorphism algebra over $\F_{83}$
The endomorphism algebra of this simple isogeny class is 4.0.1601993.1.

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.83.bd_oc$2$(not in LMFDB)