Properties

Label 1.625.i
Base field $\F_{5^{4}}$
Dimension $1$
$p$-rank $1$
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:  $\F_{5^{4}}$
Dimension:  $1$
L-polynomial:  $1 + 8 x + 625 x^{2}$
Frobenius angles:  $\pm0.551149423452$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-609}) \)
Galois group:  $C_2$
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:  $1$
Slopes:  $[0, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $634$ $391812$ $244126138$ $152587265280$ $95367445698394$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $634$ $391812$ $244126138$ $152587265280$ $95367445698394$ $59604645053769732$ $37252902973606002778$ $23283064365301081052160$ $14551915228374422072503354$ $9094947017729275493172530052$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 16 curves (of which 0 are hyperelliptic):

where $a$ is a root of the Conway polynomial.

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{5^{4}}$.

Endomorphism algebra over $\F_{5^{4}}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-609}) \).

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
1.625.ai$2$(not in LMFDB)