Properties

Label 2.47.ak_cb
Base field $\F_{47}$
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:  $\F_{47}$
Dimension:  $2$
L-polynomial:  $1 - 10 x + 53 x^{2} - 470 x^{3} + 2209 x^{4}$
Frobenius angles:  $\pm0.0934990704185$, $\pm0.573167596248$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{-22})\)
Galois group:  $C_2^2$
Jacobians:  $36$
Isomorphism classes:  38
Cyclic group of points:    yes

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1783$ $4890769$ $10694455396$ $23789918217481$ $52604763029133943$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $38$ $2216$ $103004$ $4875300$ $229369558$ $10779294422$ $506622362074$ $23811296104324$ $1119130590665348$ $52599132379842536$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 36 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{47^{3}}$.

Endomorphism algebra over $\F_{47}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-3}, \sqrt{-22})\).
Endomorphism algebra over $\overline{\F}_{47}$
The base change of $A$ to $\F_{47^{3}}$ is 1.103823.apu 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-22}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.47.k_cb$2$(not in LMFDB)
2.47.u_hm$3$(not in LMFDB)
2.47.au_hm$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.47.k_cb$2$(not in LMFDB)
2.47.u_hm$3$(not in LMFDB)
2.47.au_hm$6$(not in LMFDB)
2.47.a_ag$6$(not in LMFDB)
2.47.a_g$12$(not in LMFDB)