Properties

Label 2.127.abm_xo
Base field $\F_{127}$
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:  $\F_{127}$
Dimension:  $2$
L-polynomial:  $1 - 38 x + 612 x^{2} - 4826 x^{3} + 16129 x^{4}$
Frobenius angles:  $\pm0.128321556909$, $\pm0.222174226426$
Angle rank:  $2$ (numerical)
Number field:  4.0.2362176.1
Galois group:  $D_{4}$
Jacobians:  $16$
Isomorphism classes:  16

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $11878$ $256636068$ $4196731788574$ $67683468900310224$ $1091550310992340263118$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $90$ $15910$ $2048802$ $260176294$ $33038867550$ $4195878038710$ $532875896025990$ $67675234361335294$ $8594754747928792314$ $1091533853064314262550$

Jacobians and polarizations

This isogeny class contains the Jacobians of 16 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{127}$.

Endomorphism algebra over $\F_{127}$
The endomorphism algebra of this simple isogeny class is 4.0.2362176.1.

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.127.bm_xo$2$(not in LMFDB)