Properties

Label 2.61.abd_mt
Base field $\F_{61}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple yes
Geometrically simple yes
Primitive yes
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{61}$
Dimension:  $2$
L-polynomial:  $1 - 29 x + 331 x^{2} - 1769 x^{3} + 3721 x^{4}$
Frobenius angles:  $\pm0.00565540645541$, $\pm0.172515385279$
Angle rank:  $2$ (numerical)
Number field:  \(\Q(\zeta_{5})\)
Galois group:  $C_4$
Jacobians:  $1$
Isomorphism classes:  1

This isogeny class is simple and 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $2255$ $13194005$ $51316721555$ $191662462946405$ $713338599476250000$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $33$ $3543$ $226083$ $13842603$ $844591198$ $51520374183$ $3142742135643$ $191707295768883$ $11694145843711353$ $713342908902617398$

Jacobians and polarizations

This isogeny class contains the Jacobian of 1 curve (which is hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

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

Endomorphism algebra over $\F_{61}$
The endomorphism algebra of this simple isogeny class is \(\Q(\zeta_{5})\).

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.bd_mt$2$(not in LMFDB)
2.61.b_abd$5$(not in LMFDB)
2.61.b_dn$5$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.61.bd_mt$2$(not in LMFDB)
2.61.b_abd$5$(not in LMFDB)
2.61.b_dn$5$(not in LMFDB)
2.61.l_bz$5$(not in LMFDB)
2.61.q_gk$5$(not in LMFDB)
2.61.aq_gk$10$(not in LMFDB)
2.61.al_bz$10$(not in LMFDB)
2.61.ab_abd$10$(not in LMFDB)
2.61.ab_dn$10$(not in LMFDB)