Properties

Label 2.61.q_fu
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:  $( 1 + 2 x + 61 x^{2} )( 1 + 14 x + 61 x^{2} )$
  $1 + 16 x + 150 x^{2} + 976 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.540867587811$, $\pm0.853724980602$
Angle rank:  $2$ (numerical)
Jacobians:  $224$
Cyclic group of points:    no
Non-cyclic primes:   $2$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $4864$ $14008320$ $51480814336$ $191644800122880$ $713339682271554304$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $78$ $3766$ $226806$ $13841326$ $844592478$ $51521120998$ $3142736525958$ $191707322499166$ $11694146172825966$ $713342912338120726$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 224 curves (of which all are hyperelliptic):

  • $y^2=12 x^6+37 x^5+14 x^4+55 x^3+22 x^2+54 x+9$
  • $y^2=13 x^6+38 x^5+39 x^4+52 x^3+30 x^2+11 x+8$
  • $y^2=45 x^6+29 x^5+35 x^4+45 x^3+22 x^2+2 x+5$
  • $y^2=57 x^6+57 x^5+36 x^4+27 x^3+46 x^2+33 x+3$
  • $y^2=42 x^6+6 x^5+51 x^4+3 x^3+22 x^2+57 x+46$
  • $y^2=33 x^6+58 x^5+58 x^4+x^3+48 x^2+38 x+58$
  • $y^2=5 x^6+6 x^5+53 x^4+45 x^3+17 x^2+40 x+5$
  • $y^2=20 x^6+47 x^5+10 x^4+58 x^3+58 x^2+45 x+47$
  • $y^2=5 x^6+6 x^5+15 x^4+49 x^3+42 x^2+18 x+41$
  • $y^2=27 x^6+52 x^5+15 x^4+60 x^3+44 x^2+4$
  • $y^2=53 x^6+48 x^5+2 x^4+10 x^3+2 x^2+48 x+53$
  • $y^2=50 x^6+57 x^5+5 x^4+46 x^3+40 x^2+58 x$
  • $y^2=60 x^6+37 x^5+4 x^4+43 x^3+4 x^2+37 x+60$
  • $y^2=17 x^6+30 x^5+48 x^4+35 x^3+6 x^2+45 x+48$
  • $y^2=57 x^6+54 x^5+12 x^4+30 x^3+3 x^2+60 x+25$
  • $y^2=16 x^6+60 x^5+46 x^4+20 x^3+11 x^2+43 x+45$
  • $y^2=46 x^6+18 x^5+37 x^4+17 x^3+41 x^2+33 x+53$
  • $y^2=46 x^6+4 x^5+21 x^4+37 x^3+31 x^2+43 x+59$
  • $y^2=19 x^6+31 x^5+14 x^4+60 x^3+19 x^2+60 x+28$
  • $y^2=35 x^6+51 x^5+51 x^4+52 x^3+13 x^2+x+19$
  • and 204 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.c $\times$ 1.61.o 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.aq_fu$2$(not in LMFDB)
2.61.am_dq$2$(not in LMFDB)
2.61.m_dq$2$(not in LMFDB)
2.61.al_ds$3$(not in LMFDB)
2.61.b_eq$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.61.aq_fu$2$(not in LMFDB)
2.61.am_dq$2$(not in LMFDB)
2.61.m_dq$2$(not in LMFDB)
2.61.al_ds$3$(not in LMFDB)
2.61.b_eq$3$(not in LMFDB)
2.61.ap_fs$6$(not in LMFDB)
2.61.ad_eu$6$(not in LMFDB)
2.61.ab_eq$6$(not in LMFDB)
2.61.d_eu$6$(not in LMFDB)
2.61.l_ds$6$(not in LMFDB)
2.61.p_fs$6$(not in LMFDB)