Properties

Label 2.79.y_lc
Base field $\F_{79}$
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:  $\F_{79}$
Dimension:  $2$
L-polynomial:  $1 + 24 x + 288 x^{2} + 1896 x^{3} + 6241 x^{4}$
Frobenius angles:  $\pm0.653790398454$, $\pm0.846209601546$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(i, \sqrt{14})\)
Galois group:  $C_2^2$
Jacobians:  $66$
Isomorphism classes:  68
Cyclic group of points:    no
Non-cyclic primes:   $13$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $8450$ $38954500$ $242484723650$ $1517453070250000$ $9468247355271877250$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $104$ $6242$ $491816$ $38958918$ $3077047064$ $243087455522$ $19203902560856$ $1517108926669438$ $119851595089062824$ $9468276082626847202$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 66 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{79^{4}}$.

Endomorphism algebra over $\F_{79}$
The endomorphism algebra of this simple isogeny class is \(\Q(i, \sqrt{14})\).
Endomorphism algebra over $\overline{\F}_{79}$
The base change of $A$ to $\F_{79^{4}}$ is 1.38950081.gny 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-14}) \)$)$
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
2.79.ay_lc$2$(not in LMFDB)
2.79.a_afa$8$(not in LMFDB)
2.79.a_fa$8$(not in LMFDB)