Properties

Label 2.79.a_z
Base field $\F_{79}$
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:  $\F_{79}$
Dimension:  $2$
L-polynomial:  $1 + 25 x^{2} + 6241 x^{4}$
Frobenius angles:  $\pm0.275289025372$, $\pm0.724710974628$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{133}, \sqrt{-183})\)
Galois group:  $C_2^2$
Jacobians:  $360$
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $6267$ $39275289$ $243087003072$ $1518032690639721$ $9468276087017794827$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $80$ $6292$ $493040$ $38973796$ $3077056400$ $243086550622$ $19203908986160$ $1517108684529988$ $119851595982618320$ $9468276091408742452$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 360 curves (of which all are hyperelliptic):

  • $y^2=72 x^6+26 x^5+58 x^4+31 x^3+39 x^2+46 x+36$
  • $y^2=58 x^6+78 x^5+16 x^4+14 x^3+38 x^2+59 x+29$
  • $y^2=34 x^6+20 x^5+16 x^4+45 x^3+65 x^2+10 x+37$
  • $y^2=23 x^6+60 x^5+48 x^4+56 x^3+37 x^2+30 x+32$
  • $y^2=51 x^6+51 x^5+67 x^4+63 x^3+50 x^2+51 x+68$
  • $y^2=74 x^6+74 x^5+43 x^4+31 x^3+71 x^2+74 x+46$
  • $y^2=60 x^6+64 x^5+62 x^4+36 x^2+2 x+61$
  • $y^2=22 x^6+34 x^5+28 x^4+29 x^2+6 x+25$
  • $y^2=57 x^6+58 x^5+48 x^4+50 x^3+4 x^2+7 x+14$
  • $y^2=13 x^6+16 x^5+65 x^4+71 x^3+12 x^2+21 x+42$
  • $y^2=46 x^6+64 x^5+55 x^4+19 x^3+46 x^2+53 x+27$
  • $y^2=59 x^6+34 x^5+7 x^4+57 x^3+59 x^2+x+2$
  • $y^2=71 x^6+40 x^5+61 x^4+50 x^3+58 x^2+51 x+18$
  • $y^2=55 x^6+41 x^5+25 x^4+71 x^3+16 x^2+74 x+54$
  • $y^2=17 x^6+2 x^5+63 x^4+40 x^3+20 x^2+x+39$
  • $y^2=51 x^6+6 x^5+31 x^4+41 x^3+60 x^2+3 x+38$
  • $y^2=57 x^6+70 x^5+21 x^4+12 x^3+25 x^2+38 x+11$
  • $y^2=13 x^6+52 x^5+63 x^4+36 x^3+75 x^2+35 x+33$
  • $y^2=62 x^6+12 x^5+43 x^4+56 x^3+72 x^2+9 x+55$
  • $y^2=28 x^6+36 x^5+50 x^4+10 x^3+58 x^2+27 x+7$
  • and 340 more

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{79^{2}}$.

Endomorphism algebra over $\F_{79}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{133}, \sqrt{-183})\).
Endomorphism algebra over $\overline{\F}_{79}$
The base change of $A$ to $\F_{79^{2}}$ is 1.6241.z 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-24339}) \)$)$

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.79.a_az$4$(not in LMFDB)