Properties

Label 2.61.am_ef
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

Related objects

Downloads

Learn more

Invariants

Base field:  $\F_{61}$
Dimension:  $2$
L-polynomial:  $( 1 - 13 x + 61 x^{2} )( 1 + x + 61 x^{2} )$
  $1 - 12 x + 109 x^{2} - 732 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.187058313935$, $\pm0.520391647268$
Angle rank:  $1$ (numerical)
Jacobians:  $155$
Cyclic group of points:    no
Non-cyclic primes:   $3, 7$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $3087$ $14123025$ $51520795200$ $191680082091225$ $713406451684503087$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $50$ $3796$ $226982$ $13843876$ $844671530$ $51521216038$ $3142743297170$ $191707289170756$ $11694146092834142$ $713342911465657876$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 155 curves (of which all are hyperelliptic):

  • $y^2=x^6+x^3+29$
  • $y^2=10 x^6+29 x^5+59 x^4+46 x^3+52 x^2+46 x+15$
  • $y^2=26 x^6+35 x^5+6 x^4+50 x^3+50 x^2+6 x+37$
  • $y^2=6 x^6+56 x^5+37 x^4+45 x^3+57 x^2+51 x+59$
  • $y^2=33 x^6+51 x^5+50 x^4+49 x^3+2 x^2+10 x+29$
  • $y^2=7 x^6+29 x^5+54 x^4+8 x^2+51 x+9$
  • $y^2=23 x^6+43 x^5+2 x^4+40 x^3+2 x^2+43 x+23$
  • $y^2=10 x^6+3 x^5+6 x^4+45 x^3+26 x^2+17 x+26$
  • $y^2=20 x^6+3 x^5+45 x^4+54 x^3+24 x^2+8 x+33$
  • $y^2=40 x^6+54 x^5+x^4+57 x^3+58 x^2+50 x+58$
  • $y^2=29 x^6+33 x^5+20 x^4+37 x^3+56 x^2+37 x+34$
  • $y^2=3 x^6+55 x^5+x^4+18 x^3+x^2+55 x+3$
  • $y^2=29 x^6+49 x^5+60 x^4+50 x^3+13 x^2+25 x+29$
  • $y^2=60 x^6+51 x^5+10 x^4+34 x^3+13 x^2+26 x+59$
  • $y^2=x^6+2 x^3+30$
  • $y^2=32 x^6+22 x^5+37 x^4+8 x^3+41 x^2+37 x+37$
  • $y^2=49 x^6+18 x^5+15 x^4+3 x^3+60 x^2+23 x+14$
  • $y^2=54 x^6+21 x^5+5 x^4+54 x^3+36 x^2+32 x+14$
  • $y^2=55 x^6+48 x^5+32 x^4+48 x^3+43 x^2+4 x+35$
  • $y^2=17 x^6+22 x^5+52 x^4+30 x^3+52 x^2+22 x+17$
  • and 135 more

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{61^{6}}$.

Endomorphism algebra over $\F_{61}$
The isogeny class factors as 1.61.an $\times$ 1.61.b and its endomorphism algebra is a direct product of the endomorphism algebras for each isotypic factor. The endomorphism algebra for each factor is:
Endomorphism algebra over $\overline{\F}_{61}$
The base change of $A$ to $\F_{61^{6}}$ is 1.51520374361.xyoc 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-3}) \)$)$
Remainder of endomorphism lattice by field

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.ao_ff$2$(not in LMFDB)
2.61.m_ef$2$(not in LMFDB)
2.61.o_ff$2$(not in LMFDB)
2.61.abb_ls$3$(not in LMFDB)
2.61.ap_fg$3$(not in LMFDB)
2.61.a_acw$3$(not in LMFDB)
2.61.a_abv$3$(not in LMFDB)
2.61.a_er$3$(not in LMFDB)
2.61.m_ef$3$(not in LMFDB)
2.61.p_fg$3$(not in LMFDB)
2.61.bb_ls$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.61.ao_ff$2$(not in LMFDB)
2.61.m_ef$2$(not in LMFDB)
2.61.o_ff$2$(not in LMFDB)
2.61.abb_ls$3$(not in LMFDB)
2.61.ap_fg$3$(not in LMFDB)
2.61.a_acw$3$(not in LMFDB)
2.61.a_abv$3$(not in LMFDB)
2.61.a_er$3$(not in LMFDB)
2.61.m_ef$3$(not in LMFDB)
2.61.p_fg$3$(not in LMFDB)
2.61.bb_ls$3$(not in LMFDB)
2.61.abc_mg$6$(not in LMFDB)
2.61.aba_lf$6$(not in LMFDB)
2.61.an_ee$6$(not in LMFDB)
2.61.ac_et$6$(not in LMFDB)
2.61.ab_aci$6$(not in LMFDB)
2.61.b_aci$6$(not in LMFDB)
2.61.c_et$6$(not in LMFDB)
2.61.n_ee$6$(not in LMFDB)
2.61.ba_lf$6$(not in LMFDB)
2.61.bc_mg$6$(not in LMFDB)
2.61.a_aer$12$(not in LMFDB)
2.61.a_bv$12$(not in LMFDB)
2.61.a_cw$12$(not in LMFDB)