Properties

Label 2.47.am_fa
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:  $( 1 - 6 x + 47 x^{2} )^{2}$
  $1 - 12 x + 130 x^{2} - 564 x^{3} + 2209 x^{4}$
Frobenius angles:  $\pm0.355830380849$, $\pm0.355830380849$
Angle rank:  $1$ (numerical)
Jacobians:  $48$
Cyclic group of points:    no
Non-cyclic primes:   $2, 3, 7$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1764$ $5143824$ $10910638116$ $23821583901696$ $52588452181045284$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $36$ $2326$ $105084$ $4881790$ $229298436$ $10778836822$ $506623038300$ $23811303958654$ $1119130580745828$ $52599132068734486$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 48 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{47}$
The isogeny class factors as 1.47.ag 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-38}) \)$)$

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.a_cg$2$(not in LMFDB)
2.47.m_fa$2$(not in LMFDB)
2.47.g_al$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.47.a_cg$2$(not in LMFDB)
2.47.m_fa$2$(not in LMFDB)
2.47.g_al$3$(not in LMFDB)
2.47.a_acg$4$(not in LMFDB)
2.47.ag_al$6$(not in LMFDB)