Properties

Label 2.97.ac_c
Base field $\F_{97}$
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:  $\F_{97}$
Dimension:  $2$
L-polynomial:  $1 - 2 x + 2 x^{2} - 194 x^{3} + 9409 x^{4}$
Frobenius angles:  $\pm0.227127002908$, $\pm0.727127002908$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(i, \sqrt{193})\)
Galois group:  $C_2^2$
Jacobians:  $316$
Cyclic group of points:    no
Non-cyclic primes:   $2, 3$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $9216$ $88547328$ $832444646400$ $7840629295939584$ $73743204085842871296$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $96$ $9410$ $912096$ $88565374$ $8587432416$ $832972004930$ $80798296734048$ $7837433297177854$ $760231057168540512$ $73742412689492826050$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 316 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{97^{4}}$.

Endomorphism algebra over $\F_{97}$
The endomorphism algebra of this simple isogeny class is \(\Q(i, \sqrt{193})\).
Endomorphism algebra over $\overline{\F}_{97}$
The base change of $A$ to $\F_{97^{4}}$ is 1.88529281.basc 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-193}) \)$)$
Remainder of endomorphism lattice by field

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.97.c_c$2$(not in LMFDB)
2.97.a_ahk$8$(not in LMFDB)
2.97.a_hk$8$(not in LMFDB)