Properties

Label 2.79.s_jf
Base field $\F_{79}$
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:  $\F_{79}$
Dimension:  $2$
L-polynomial:  $( 1 + 9 x + 79 x^{2} )^{2}$
  $1 + 18 x + 239 x^{2} + 1422 x^{3} + 6241 x^{4}$
Frobenius angles:  $\pm0.668983296649$, $\pm0.668983296649$
Angle rank:  $1$ (numerical)
Jacobians:  $21$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $7921$ $39929761$ $241705956496$ $1517619410523225$ $9468595729943338921$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $98$ $6396$ $490232$ $38963188$ $3077160278$ $243085485246$ $19203918512282$ $1517108879823268$ $119851594600804328$ $9468276089539753356$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 21 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{79}$.

Endomorphism algebra over $\F_{79}$
The isogeny class factors as 1.79.j 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-235}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.79.as_jf$2$(not in LMFDB)
2.79.a_cz$2$(not in LMFDB)
2.79.aj_c$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.79.as_jf$2$(not in LMFDB)
2.79.a_cz$2$(not in LMFDB)
2.79.aj_c$3$(not in LMFDB)
2.79.a_acz$4$(not in LMFDB)
2.79.j_c$6$(not in LMFDB)