Properties

Label 2.47.a_bt
Base field $\F_{47}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
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:  $( 1 - 7 x + 47 x^{2} )( 1 + 7 x + 47 x^{2} )$
  $1 + 45 x^{2} + 2209 x^{4}$
Frobenius angles:  $\pm0.329450163008$, $\pm0.670549836992$
Angle rank:  $1$ (numerical)
Jacobians:  $123$
Cyclic group of points:    yes

This isogeny class is not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2255$ $5085025$ $10779008240$ $23834656305625$ $52599132511810775$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $48$ $2300$ $103824$ $4884468$ $229345008$ $10778801150$ $506623120464$ $23811294727588$ $1119130473102768$ $52599132787791500$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 123 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 isogeny class factors as 1.47.ah $\times$ 1.47.h and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{47}$
The base change of $A$ to $\F_{47^{2}}$ is 1.2209.bt 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$2$(not in LMFDB)
2.47.o_fn$2$(not in LMFDB)
2.47.a_abt$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.47.ao_fn$2$(not in LMFDB)
2.47.o_fn$2$(not in LMFDB)
2.47.a_abt$4$(not in LMFDB)
2.47.ah_c$6$(not in LMFDB)
2.47.h_c$6$(not in LMFDB)