Properties

Label 2.89.a_da
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:  $( 1 - 10 x + 89 x^{2} )( 1 + 10 x + 89 x^{2} )$
  $1 + 78 x^{2} + 7921 x^{4}$
Frobenius angles:  $\pm0.322192315511$, $\pm0.677807684489$
Angle rank:  $1$ (numerical)
Jacobians:  $707$
Cyclic group of points:    no
Non-cyclic primes:   $2, 5$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $8000$ $64000000$ $496979912000$ $3937813504000000$ $31181719938528200000$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $90$ $8078$ $704970$ $62761758$ $5584059450$ $496978533038$ $44231334895530$ $3936588866233918$ $350356403707485210$ $31181719947090216398$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 707 curves (of which all are hyperelliptic):

  • $y^2=83 x^6+84 x^5+80 x^4+27 x^3+50 x^2+75 x+25$
  • $y^2=71 x^6+74 x^5+62 x^4+81 x^3+61 x^2+47 x+75$
  • $y^2=76 x^6+31 x^5+9 x^4+41 x^3+38 x^2+79 x+62$
  • $y^2=50 x^6+4 x^5+27 x^4+34 x^3+25 x^2+59 x+8$
  • $y^2=77 x^6+69 x^5+6 x^4+16 x^3+22 x^2+2 x+68$
  • $y^2=53 x^6+29 x^5+18 x^4+48 x^3+66 x^2+6 x+26$
  • $y^2=73 x^5+45 x^4+7 x^2+70 x+7$
  • $y^2=88 x^6+35 x^5+11 x^4+80 x^3+26 x^2+34 x+82$
  • $y^2=86 x^6+16 x^5+33 x^4+62 x^3+78 x^2+13 x+68$
  • $y^2=52 x^6+66 x^5+11 x^4+72 x^3+24 x^2+6 x$
  • $y^2=67 x^6+20 x^5+33 x^4+38 x^3+72 x^2+18 x$
  • $y^2=50 x^6+69 x^5+27 x^3+5 x^2+78 x+77$
  • $y^2=61 x^6+29 x^5+81 x^3+15 x^2+56 x+53$
  • $y^2=22 x^6+46 x^5+37 x^4+68 x^3+39 x^2+82 x+24$
  • $y^2=66 x^6+49 x^5+22 x^4+26 x^3+28 x^2+68 x+72$
  • $y^2=14 x^6+75 x^5+86 x^4+65 x^3+34 x^2+48 x+9$
  • $y^2=42 x^6+47 x^5+80 x^4+17 x^3+13 x^2+55 x+27$
  • $y^2=31 x^6+46 x^5+83 x^4+81 x^3+73 x^2+70 x+11$
  • $y^2=88 x^6+40 x^5+39 x^4+68 x^3+66 x^2+64 x+37$
  • $y^2=82 x^6+63 x^5+46 x^4+73 x^3+68 x^2+66 x+73$
  • and 687 more

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.ak $\times$ 1.89.k 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.da 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.au_ks$2$(not in LMFDB)
2.89.u_ks$2$(not in LMFDB)
2.89.abg_qs$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.89.au_ks$2$(not in LMFDB)
2.89.u_ks$2$(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.k_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)