Properties

Label 2.47.a_k
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:  $1 + 10 x^{2} + 2209 x^{4}$
Frobenius angles:  $\pm0.266963477027$, $\pm0.733036522973$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{21}, \sqrt{-26})\)
Galois group:  $C_2^2$
Jacobians:  $468$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2220$ $4928400$ $10779150060$ $23853456000000$ $52599132468869100$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $48$ $2230$ $103824$ $4888318$ $229345008$ $10779084790$ $506623120464$ $23811268890238$ $1119130473102768$ $52599132701908150$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 468 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{47^{2}}$.

Endomorphism algebra over $\F_{47}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{21}, \sqrt{-26})\).
Endomorphism algebra over $\overline{\F}_{47}$
The base change of $A$ to $\F_{47^{2}}$ is 1.2209.k 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-546}) \)$)$

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.47.a_ak$4$(not in LMFDB)