Properties

Label 2.25.ao_dt
Base field $\F_{5^{2}}$
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:  $\F_{5^{2}}$
Dimension:  $2$
L-polynomial:  $1 - 14 x + 97 x^{2} - 350 x^{3} + 625 x^{4}$
Frobenius angles:  $\pm0.181719349551$, $\pm0.311346897918$
Angle rank:  $2$ (numerical)
Number field:  4.0.128576.2
Galois group:  $D_{4}$
Jacobians:  $4$
Isomorphism classes:  4

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $359$ $390233$ $248555804$ $153258937721$ $95415159378519$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $12$ $624$ $15906$ $392340$ $9770512$ $244142022$ $6103486128$ $152587981092$ $3814698828306$ $95367433546144$

Jacobians and polarizations

This isogeny class contains the Jacobians of 4 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{5^{2}}$.

Endomorphism algebra over $\F_{5^{2}}$
The endomorphism algebra of this simple isogeny class is 4.0.128576.2.

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.25.o_dt$2$2.625.ac_bhb