Properties

Label 2.89.am_fh
Base field $\F_{89}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple no
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{89}$
Dimension:  $2$
L-polynomial:  $1 - 12 x + 137 x^{2} - 1068 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.213651833311$, $\pm0.546985166645$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{77})\)
Galois group:  $C_2^2$
Jacobians:  $300$

This isogeny class is simple but not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6979$ $63781081$ $496982183152$ $3936655125371241$ $31183096917870446899$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $78$ $8052$ $704970$ $62743300$ $5584306038$ $496983075342$ $44231323655478$ $3936588681336964$ $350356403707485210$ $31181719920865755252$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 300 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{89^{6}}$.

Endomorphism algebra over $\F_{89}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-3}, \sqrt{77})\).
Endomorphism algebra over $\overline{\F}_{89}$
The base change of $A$ to $\F_{89^{6}}$ is 1.496981290961.bytva 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-231}) \)$)$
Remainder of endomorphism lattice by field

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.89.a_afa$3$(not in LMFDB)
2.89.m_fh$3$(not in LMFDB)
2.89.a_afa$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.89.a_afa$3$(not in LMFDB)
2.89.m_fh$3$(not in LMFDB)
2.89.a_afa$6$(not in LMFDB)
2.89.a_fa$12$(not in LMFDB)