Properties

Label 2.61.au_io
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:  $( 1 - 10 x + 61 x^{2} )^{2}$
  $1 - 20 x + 222 x^{2} - 1220 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.278857938376$, $\pm0.278857938376$
Angle rank:  $1$ (numerical)
Jacobians:  $49$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2704$ $14017536$ $51898307344$ $191900067840000$ $713374923911023504$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $42$ $3766$ $228642$ $13859758$ $844634202$ $51519904486$ $3142735825362$ $191707271553118$ $11694146106042762$ $713342914323062806$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 49 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{61}$
The isogeny class factors as 1.61.ak 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-1}) \)$)$

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.a_w$2$(not in LMFDB)
2.61.u_io$2$(not in LMFDB)
2.61.k_bn$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.61.a_w$2$(not in LMFDB)
2.61.u_io$2$(not in LMFDB)
2.61.k_bn$3$(not in LMFDB)
2.61.ay_kg$4$(not in LMFDB)
2.61.aw_ji$4$(not in LMFDB)
2.61.ac_c$4$(not in LMFDB)
2.61.a_aw$4$(not in LMFDB)
2.61.c_c$4$(not in LMFDB)
2.61.w_ji$4$(not in LMFDB)
2.61.y_kg$4$(not in LMFDB)
2.61.ak_bn$6$(not in LMFDB)
2.61.a_aeq$8$(not in LMFDB)
2.61.a_eq$8$(not in LMFDB)
2.61.am_df$12$(not in LMFDB)
2.61.m_df$12$(not in LMFDB)