Properties

Label 2.97.abg_ri
Base field $\F_{97}$
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:  $\F_{97}$
Dimension:  $2$
L-polynomial:  $( 1 - 16 x + 97 x^{2} )^{2}$
  $1 - 32 x + 450 x^{2} - 3104 x^{3} + 9409 x^{4}$
Frobenius angles:  $\pm0.198227810371$, $\pm0.198227810371$
Angle rank:  $1$ (numerical)
Jacobians:  $26$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6724$ $87385104$ $833996338756$ $7840085270593536$ $73745594591001372484$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $66$ $9286$ $913794$ $88559230$ $8587710786$ $832975028422$ $80798296912770$ $7837433500052734$ $760231055939215938$ $73742412655196687686$

Jacobians and polarizations

This isogeny class contains the Jacobians of 26 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{97}$.

Endomorphism algebra over $\F_{97}$
The isogeny class factors as 1.97.aq 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-33}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.97.a_ack$2$(not in LMFDB)
2.97.bg_ri$2$(not in LMFDB)
2.97.q_gd$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.97.a_ack$2$(not in LMFDB)
2.97.bg_ri$2$(not in LMFDB)
2.97.q_gd$3$(not in LMFDB)
2.97.a_ck$4$(not in LMFDB)
2.97.aq_gd$6$(not in LMFDB)