Properties

Label 2.97.as_hm
Base field $\F_{97}$
Dimension $2$
$p$-rank $1$
Ordinary no
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:  $( 1 - 18 x + 97 x^{2} )( 1 + 97 x^{2} )$
  $1 - 18 x + 194 x^{2} - 1746 x^{3} + 9409 x^{4}$
Frobenius angles:  $\pm0.133124938748$, $\pm0.5$
Angle rank:  $1$ (numerical)
Jacobians:  $256$

This isogeny class is not simple, primitive, not ordinary, and not supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

$p$-rank:  $1$
Slopes:  $[0, 1/2, 1/2, 1]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $7840$ $89125120$ $832431701920$ $7835937590476800$ $73743203961373559200$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $80$ $9474$ $912080$ $88512382$ $8587432400$ $832975302786$ $80798302045520$ $7837433590698238$ $760231060071363920$ $73742412715352038914$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 256 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{97^{2}}$.

Endomorphism algebra over $\F_{97}$
The isogeny class factors as 1.97.as $\times$ 1.97.a 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 $\overline{\F}_{97}$
The base change of $A$ to $\F_{97^{2}}$ is 1.9409.afa $\times$ 1.9409.hm. The endomorphism algebra for each factor is:

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.s_hm$2$(not in LMFDB)
2.97.ai_hm$4$(not in LMFDB)
2.97.i_hm$4$(not in LMFDB)