Properties

Label 2.89.au_ks
Base field $\F_{89}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
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:  $( 1 - 10 x + 89 x^{2} )^{2}$
  $1 - 20 x + 278 x^{2} - 1780 x^{3} + 7921 x^{4}$
Frobenius angles:  $\pm0.322192315511$, $\pm0.322192315511$
Angle rank:  $1$ (numerical)
Jacobians:  $80$

This isogeny class is not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6400$ $64000000$ $499340089600$ $3937813504000000$ $31181149811270560000$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $70$ $8078$ $708310$ $62761758$ $5583957350$ $496978533038$ $44231316403190$ $3936588866233918$ $350356405958621830$ $31181719947090216398$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 80 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{89}$
The isogeny class factors as 1.89.ak 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-1}) \)$)$

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_da$2$(not in LMFDB)
2.89.u_ks$2$(not in LMFDB)
2.89.k_l$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.89.a_da$2$(not in LMFDB)
2.89.u_ks$2$(not in LMFDB)
2.89.k_l$3$(not in LMFDB)
2.89.abg_qs$4$(not in LMFDB)
2.89.aba_na$4$(not in LMFDB)
2.89.ag_s$4$(not in LMFDB)
2.89.a_ada$4$(not in LMFDB)
2.89.g_s$4$(not in LMFDB)
2.89.ba_na$4$(not in LMFDB)
2.89.bg_qs$4$(not in LMFDB)
2.89.ak_l$6$(not in LMFDB)
2.89.a_age$8$(not in LMFDB)
2.89.a_ge$8$(not in LMFDB)
2.89.aq_gl$12$(not in LMFDB)
2.89.q_gl$12$(not in LMFDB)