Properties

Label 2.47.a_by
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:  $1 + 50 x^{2} + 2209 x^{4}$
Frobenius angles:  $\pm0.339263688900$, $\pm0.660736311100$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(i, \sqrt{11})\)
Galois group:  $C_2^2$
Jacobians:  $324$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2260$ $5107600$ $10779008980$ $23830018560000$ $52599132387625300$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $48$ $2310$ $103824$ $4883518$ $229345008$ $10778802630$ $506623120464$ $23811298823038$ $1119130473102768$ $52599132539420550$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 324 curves (of which all are hyperelliptic):

  • $y^2=8 x^6+12 x^5+35 x^4+30 x^3+16 x^2+15 x+44$
  • $y^2=38 x^6+25 x^5+26 x^4+2 x^3+18 x^2+26 x+9$
  • $y^2=2 x^6+31 x^5+36 x^4+10 x^3+43 x^2+36 x+45$
  • $y^2=38 x^6+41 x^5+45 x^4+41 x^3+9 x^2+43 x+27$
  • $y^2=26 x^6+30 x^5+45 x^4+7 x^3+20 x^2+22 x+36$
  • $y^2=36 x^6+9 x^5+37 x^4+35 x^3+6 x^2+16 x+39$
  • $y^2=36 x^6+28 x^5+31 x^4+8 x^3+46 x^2+9 x+40$
  • $y^2=39 x^6+46 x^5+14 x^4+40 x^3+42 x^2+45 x+12$
  • $y^2=46 x^6+32 x^5+28 x^4+20 x^3+11 x^2+27 x+42$
  • $y^2=38 x^6+19 x^5+7 x^4+7 x^3+35 x^2+5 x+3$
  • $y^2=39 x^6+4 x^5+18 x^4+15 x^3+41 x^2+26 x+4$
  • $y^2=7 x^6+20 x^5+43 x^4+28 x^3+17 x^2+36 x+20$
  • $y^2=x^6+24 x^5+3 x^4+12 x^3+12 x^2+3 x+31$
  • $y^2=5 x^6+26 x^5+15 x^4+13 x^3+13 x^2+15 x+14$
  • $y^2=2 x^6+12 x^5+42 x^3+19 x^2+3 x+2$
  • $y^2=10 x^6+13 x^5+22 x^3+x^2+15 x+10$
  • $y^2=7 x^6+36 x^5+39 x^4+35 x^3+36 x^2+28 x+28$
  • $y^2=35 x^6+39 x^5+7 x^4+34 x^3+39 x^2+46 x+46$
  • $y^2=16 x^6+18 x^5+22 x^4+13 x^3+13 x^2+38 x+35$
  • $y^2=33 x^6+43 x^5+16 x^4+18 x^3+18 x^2+2 x+34$
  • and 304 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 \(\Q(i, \sqrt{11})\).
Endomorphism algebra over $\overline{\F}_{47}$
The base change of $A$ to $\F_{47^{2}}$ is 1.2209.by 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-11}) \)$)$

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.ay_je$4$(not in LMFDB)
2.47.a_aby$4$(not in LMFDB)
2.47.y_je$4$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.47.ay_je$4$(not in LMFDB)
2.47.a_aby$4$(not in LMFDB)
2.47.y_je$4$(not in LMFDB)
2.47.am_dt$12$(not in LMFDB)
2.47.m_dt$12$(not in LMFDB)