Properties

Label 2.89.s_jb
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:  $1 + 18 x + 235 x^{2} + 1602 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.569742487015$, $\pm0.763590846318$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-2}, \sqrt{-3})\)
Galois group:  $C_2^2$
Jacobians:  $291$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $9777$ $63912249$ $495537155136$ $3936932223957225$ $31181760230175333777$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $108$ $8068$ $702918$ $62747716$ $5584066668$ $496982005486$ $44231327822412$ $3936588710182276$ $350356405887183222$ $31181719918850164228$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 291 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{89^{3}}$.

Endomorphism algebra over $\F_{89}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-2}, \sqrt{-3})\).
Endomorphism algebra over $\overline{\F}_{89}$
The base change of $A$ to $\F_{89^{3}}$ is 1.704969.abnm 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-2}) \)$)$

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.as_jb$2$(not in LMFDB)
2.89.abk_ti$3$(not in LMFDB)
2.89.as_jb$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.89.as_jb$2$(not in LMFDB)
2.89.abk_ti$3$(not in LMFDB)
2.89.as_jb$6$(not in LMFDB)
2.89.a_afq$6$(not in LMFDB)
2.89.bk_ti$6$(not in LMFDB)
2.89.a_fq$12$(not in LMFDB)
2.89.ai_bg$24$(not in LMFDB)
2.89.i_bg$24$(not in LMFDB)