Properties

Label 2.61.ai_d
Base field $\F_{61}$
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:  $\F_{61}$
Dimension:  $2$
L-polynomial:  $1 - 8 x + 3 x^{2} - 488 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.00448322842836$, $\pm0.662183438238$
Angle rank:  $1$ (numerical)
Number field:  \(\Q(\sqrt{-3}, \sqrt{-5})\)
Galois group:  $C_2^2$
Jacobians:  $10$
Isomorphism classes:  14
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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $3229$ $13629609$ $51089560900$ $191650852437849$ $713321418179193709$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $54$ $3664$ $225078$ $13841764$ $844570854$ $51519469678$ $3142740769614$ $191707301935684$ $11694145663746798$ $713342910621290704$

Jacobians and polarizations

This isogeny class is principally polarizable and contains the Jacobians of 10 curves (of which all are hyperelliptic):

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{61^{3}}$.

Endomorphism algebra over $\F_{61}$
The endomorphism algebra of this simple isogeny class is \(\Q(\sqrt{-3}, \sqrt{-5})\).
Endomorphism algebra over $\overline{\F}_{61}$
The base change of $A$ to $\F_{61^{3}}$ is 1.226981.abkq 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-5}) \)$)$

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.i_d$2$(not in LMFDB)
2.61.q_he$3$(not in LMFDB)
2.61.aq_he$6$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.61.i_d$2$(not in LMFDB)
2.61.q_he$3$(not in LMFDB)
2.61.aq_he$6$(not in LMFDB)
2.61.a_cg$6$(not in LMFDB)
2.61.a_acg$12$(not in LMFDB)