Properties

Label 2.61.h_bs
Base field $\F_{61}$
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:  $\F_{61}$
Dimension:  $2$
L-polynomial:  $( 1 - 6 x + 61 x^{2} )( 1 + 13 x + 61 x^{2} )$
  $1 + 7 x + 44 x^{2} + 427 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.374508117845$, $\pm0.812941686065$
Angle rank:  $2$ (numerical)
Jacobians:  $126$
Cyclic group of points:    no
Non-cyclic primes:   $2, 5$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4200$ $13994400$ $51679555200$ $191780433129600$ $713249628203805000$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $69$ $3761$ $227682$ $13851121$ $844485849$ $51520471238$ $3142742158989$ $191707340994241$ $11694146296274442$ $713342908935551801$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 126 curves (of which all are hyperelliptic):

  • $y^2=35 x^6+24 x^5+44 x^4+4 x^3+43 x^2+9 x+51$
  • $y^2=15 x^6+47 x^5+38 x^4+3 x^3+14 x^2+20 x+45$
  • $y^2=43 x^6+27 x^5+26 x^4+13 x^3+19 x^2+21 x+38$
  • $y^2=21 x^6+8 x^5+24 x^4+43 x^3+52 x^2+14 x+14$
  • $y^2=48 x^6+35 x^5+17 x^4+57 x^3+56 x^2+50 x+20$
  • $y^2=60 x^6+33 x^5+18 x^4+33 x^3+12 x^2+30 x+56$
  • $y^2=12 x^6+26 x^5+45 x^4+24 x^3+28 x^2+55 x+48$
  • $y^2=15 x^6+57 x^5+11 x^4+59 x^3+19 x^2+19 x+39$
  • $y^2=55 x^6+13 x^5+42 x^4+13 x^3+40 x^2+41 x+57$
  • $y^2=56 x^6+21 x^5+9 x^4+16 x^3+46 x^2+49 x+7$
  • $y^2=39 x^6+53 x^5+6 x^4+10 x^3+2 x^2+33 x+57$
  • $y^2=3 x^6+37 x^5+30 x^4+56 x^3+34 x^2+37 x+49$
  • $y^2=28 x^6+23 x^5+49 x^4+26 x^3+30 x^2+12 x+17$
  • $y^2=2 x^6+50 x^5+26 x^4+5 x^3+24 x^2+51 x+25$
  • $y^2=16 x^6+46 x^5+33 x^4+56 x^3+45 x^2+37 x+45$
  • $y^2=9 x^6+2 x^5+45 x^4+27 x^3+58 x^2+22 x+16$
  • $y^2=5 x^6+33 x^5+55 x^4+41 x^3+40 x^2+35 x+56$
  • $y^2=25 x^6+29 x^5+20 x^4+14 x^3+35 x^2+54 x$
  • $y^2=49 x^6+50 x^5+12 x^4+x^3+18 x^2+38 x+14$
  • $y^2=49 x^6+34 x^5+53 x^4+37 x^3+20 x^2+2 x+13$
  • and 106 more

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{61}$.

Endomorphism algebra over $\F_{61}$
The isogeny class factors as 1.61.ag $\times$ 1.61.n and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.61.at_hs$2$(not in LMFDB)
2.61.ah_bs$2$(not in LMFDB)
2.61.t_hs$2$(not in LMFDB)
2.61.au_hy$3$(not in LMFDB)
2.61.af_em$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.61.at_hs$2$(not in LMFDB)
2.61.ah_bs$2$(not in LMFDB)
2.61.t_hs$2$(not in LMFDB)
2.61.au_hy$3$(not in LMFDB)
2.61.af_em$3$(not in LMFDB)
2.61.ai_bm$6$(not in LMFDB)
2.61.ah_ey$6$(not in LMFDB)
2.61.f_em$6$(not in LMFDB)
2.61.h_ey$6$(not in LMFDB)
2.61.i_bm$6$(not in LMFDB)
2.61.u_hy$6$(not in LMFDB)