Properties

Label 2.89.a_ada
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:  $( 1 - 16 x + 89 x^{2} )( 1 + 16 x + 89 x^{2} )$
  $1 - 78 x^{2} + 7921 x^{4}$
Frobenius angles:  $\pm0.177807684489$, $\pm0.822192315511$
Angle rank:  $1$ (numerical)
Jacobians:  $351$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $7844$ $61528336$ $496982669924$ $3937813504000000$ $31181719921404167204$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $90$ $7766$ $704970$ $62761758$ $5584059450$ $496984048886$ $44231334895530$ $3936588866233918$ $350356403707485210$ $31181719912842150806$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 351 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{89^{2}}$.

Endomorphism algebra over $\F_{89}$
The isogeny class factors as 1.89.aq $\times$ 1.89.q and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{89}$
The base change of $A$ to $\F_{89^{2}}$ is 1.7921.ada 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.abg_qs$2$(not in LMFDB)
2.89.bg_qs$2$(not in LMFDB)
2.89.aba_na$4$(not in LMFDB)

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

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