Properties

Label 2.47.a_abt
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:  $1 - 45 x^{2} + 2209 x^{4}$
Frobenius angles:  $\pm0.170549836992$, $\pm0.829450163008$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(i, \sqrt{139})\)
Galois group:  $C_2^2$
Jacobians:  $63$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2165$ $4687225$ $10779422420$ $23834656305625$ $52599131959849325$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $48$ $2120$ $103824$ $4884468$ $229345008$ $10779629510$ $506623120464$ $23811294727588$ $1119130473102768$ $52599131683868600$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 63 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 \(\Q(i, \sqrt{139})\).
Endomorphism algebra over $\overline{\F}_{47}$
The base change of $A$ to $\F_{47^{2}}$ is 1.2209.abt 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-139}) \)$)$

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.ao_fn$4$(not in LMFDB)
2.47.a_bt$4$(not in LMFDB)
2.47.o_fn$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.47.ao_fn$4$(not in LMFDB)
2.47.a_bt$4$(not in LMFDB)
2.47.o_fn$4$(not in LMFDB)
2.47.ah_c$12$(not in LMFDB)
2.47.h_c$12$(not in LMFDB)