Properties

Label 2.47.a_bl
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

Related objects

Downloads

Learn more

Invariants

Base field:  $\F_{47}$
Dimension:  $2$
L-polynomial:  $1 + 37 x^{2} + 2209 x^{4}$
Frobenius angles:  $\pm0.314388191939$, $\pm0.685611808061$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{57}, \sqrt{-131})\)
Galois group:  $C_2^2$
Jacobians:  $190$
Isomorphism classes:  200
Cyclic group of points:    yes

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2247$ $5049009$ $10779020784$ $23841062018361$ $52599132648452607$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $48$ $2284$ $103824$ $4885780$ $229345008$ $10778826238$ $506623120464$ $23811287587684$ $1119130473102768$ $52599133061075164$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 190 curves (of which all are hyperelliptic):

  • $y^2=4 x^6+15 x^5+38 x^4+7 x^3+22 x^2+40 x+43$
  • $y^2=20 x^6+28 x^5+2 x^4+35 x^3+16 x^2+12 x+27$
  • $y^2=44 x^6+39 x^5+44 x^4+11 x^3+41 x^2+31 x+18$
  • $y^2=32 x^6+7 x^5+32 x^4+8 x^3+17 x^2+14 x+43$
  • $y^2=10 x^6+16 x^5+41 x^4+19 x^3+38 x^2+31 x+13$
  • $y^2=3 x^6+33 x^5+17 x^4+x^3+2 x^2+14 x+18$
  • $y^2=39 x^6+16 x^5+30 x^4+17 x^3+37 x^2+42 x+34$
  • $y^2=7 x^6+33 x^5+9 x^4+38 x^3+44 x^2+22 x+29$
  • $y^2=13 x^6+44 x^5+6 x^3+17 x^2+21 x+45$
  • $y^2=18 x^6+32 x^5+30 x^3+38 x^2+11 x+37$
  • $y^2=9 x^6+3 x^5+12 x^4+x^3+35 x^2+3 x+24$
  • $y^2=45 x^6+15 x^5+13 x^4+5 x^3+34 x^2+15 x+26$
  • $y^2=7 x^6+28 x^5+2 x^4+10 x^3+40 x^2+18 x+24$
  • $y^2=35 x^6+46 x^5+10 x^4+3 x^3+12 x^2+43 x+26$
  • $y^2=40 x^6+44 x^5+33 x^4+32 x^3+14 x^2+39 x+24$
  • $y^2=12 x^6+32 x^5+24 x^4+19 x^3+23 x^2+7 x+26$
  • $y^2=45 x^6+20 x^5+17 x^4+32 x^3+7 x^2+22 x+10$
  • $y^2=37 x^6+6 x^5+38 x^4+19 x^3+35 x^2+16 x+3$
  • $y^2=41 x^6+35 x^5+29 x^4+3 x^3+9 x^2+44 x+36$
  • $y^2=42 x^6+30 x^5+23 x^4+33 x^3+16 x^2+33 x+24$
  • and 170 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 \(\Q(\sqrt{57}, \sqrt{-131})\).
Endomorphism algebra over $\overline{\F}_{47}$
The base change of $A$ to $\F_{47^{2}}$ is 1.2209.bl 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-7467}) \)$)$

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.47.a_abl$4$(not in LMFDB)