Properties

Label 2.47.a_abe
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:  $1 - 30 x^{2} + 2209 x^{4}$
Frobenius angles:  $\pm0.198301488982$, $\pm0.801698511018$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(i, \sqrt{31})\)
Galois group:  $C_2^2$
Jacobians:  $171$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2180$ $4752400$ $10779387140$ $23845642240000$ $52599131777792900$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $48$ $2150$ $103824$ $4886718$ $229345008$ $10779558950$ $506623120464$ $23811281427838$ $1119130473102768$ $52599131319755750$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 171 curves (of which all are hyperelliptic):

  • $y^2=37 x^6+24 x^5+20 x^4+2 x^3+45 x^2+44 x+18$
  • $y^2=44 x^6+26 x^5+6 x^4+10 x^3+37 x^2+32 x+43$
  • $y^2=21 x^6+19 x^5+5 x^4+20 x^3+33 x^2+12 x+4$
  • $y^2=42 x^6+22 x^5+11 x^4+35 x^2+8 x+12$
  • $y^2=39 x^6+24 x^5+13 x^4+19 x^3+17 x^2+14 x+20$
  • $y^2=7 x^6+26 x^5+18 x^4+x^3+38 x^2+23 x+6$
  • $y^2=37 x^6+3 x^5+36 x^4+31 x^3+45 x^2+11 x+22$
  • $y^2=44 x^6+15 x^5+39 x^4+14 x^3+37 x^2+8 x+16$
  • $y^2=34 x^6+24 x^5+8 x^4+7 x^3+44 x^2+25 x+31$
  • $y^2=29 x^6+26 x^5+40 x^4+35 x^3+32 x^2+31 x+14$
  • $y^2=20 x^6+40 x^5+4 x^4+44 x^3+21 x^2+35 x+24$
  • $y^2=6 x^6+12 x^5+20 x^4+32 x^3+11 x^2+34 x+26$
  • $y^2=35 x^6+24 x^5+12 x^4+15 x^3+26 x^2+13 x+6$
  • $y^2=7 x^6+40 x^5+3 x^4+8 x^3+28 x^2+45 x+46$
  • $y^2=22 x^6+33 x^5+11 x^4+36 x^3+25 x^2+5 x+46$
  • $y^2=16 x^6+24 x^5+8 x^4+39 x^3+31 x^2+25 x+42$
  • $y^2=25 x^6+27 x^5+19 x^4+26 x^3+x^2+17 x+23$
  • $y^2=13 x^6+33 x^5+41 x^4+23 x^3+32 x^2+30 x+21$
  • $y^2=7 x^6+35 x^5+33 x^4+21 x^3+2 x^2+40 x+11$
  • $y^2=35 x^6+34 x^5+24 x^4+11 x^3+10 x^2+12 x+8$
  • and 151 more

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 \(\Q(i, \sqrt{31})\).
Endomorphism algebra over $\overline{\F}_{47}$
The base change of $A$ to $\F_{47^{2}}$ is 1.2209.abe 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-31}) \)$)$

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.aq_gc$4$(not in LMFDB)
2.47.a_be$4$(not in LMFDB)
2.47.q_gc$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.47.aq_gc$4$(not in LMFDB)
2.47.a_be$4$(not in LMFDB)
2.47.q_gc$4$(not in LMFDB)
2.47.ai_r$12$(not in LMFDB)
2.47.i_r$12$(not in LMFDB)