Properties

Label 2.47.a_abi
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:  $1 - 34 x^{2} + 2209 x^{4}$
Frobenius angles:  $\pm0.191097871214$, $\pm0.808902128786$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{2}, \sqrt{-15})\)
Galois group:  $C_2^2$
Jacobians:  $194$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2176$ $4734976$ $10779401344$ $23843142107136$ $52599131794961536$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $48$ $2142$ $103824$ $4886206$ $229345008$ $10779587358$ $506623120464$ $23811284899198$ $1119130473102768$ $52599131354093022$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 194 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 \(\Q(\sqrt{2}, \sqrt{-15})\).
Endomorphism algebra over $\overline{\F}_{47}$
The base change of $A$ to $\F_{47^{2}}$ is 1.2209.abi 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-30}) \)$)$

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_bi$4$(not in LMFDB)
2.47.aq_ey$8$(not in LMFDB)
2.47.q_ey$8$(not in LMFDB)