Properties

Label 2.49.ay_ji
Base field $\F_{7^{2}}$
Dimension $2$
$p$-rank $2$
Ordinary yes
Supersingular no
Simple no
Geometrically simple no
Primitive no
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{7^{2}}$
Dimension:  $2$
L-polynomial:  $( 1 - 12 x + 49 x^{2} )^{2}$
  $1 - 24 x + 242 x^{2} - 1176 x^{3} + 2401 x^{4}$
Frobenius angles:  $\pm0.172237328522$, $\pm0.172237328522$
Angle rank:  $1$ (numerical)
Jacobians:  $5$

This isogeny class is not simple, not 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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $1444$ $5550736$ $13849994596$ $33263917830144$ $79809480702695524$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $26$ $2310$ $117722$ $5770174$ $282536186$ $13841755206$ $678225703034$ $33232939199614$ $1628413572591578$ $79792265570914950$

Jacobians and polarizations

This isogeny class contains the Jacobians of 5 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{7^{2}}$.

Endomorphism algebra over $\F_{7^{2}}$
The isogeny class factors as 1.49.am 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-13}) \)$)$

Base change

This isogeny class is not primitive. It is a base change from the following isogeny classes over subfields of $\F_{7^{2}}$.

SubfieldPrimitive Model
$\F_{7}$2.7.a_am

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.49.a_abu$2$(not in LMFDB)
2.49.y_ji$2$(not in LMFDB)
2.49.m_dr$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.49.a_abu$2$(not in LMFDB)
2.49.y_ji$2$(not in LMFDB)
2.49.m_dr$3$(not in LMFDB)
2.49.a_bu$4$(not in LMFDB)
2.49.am_dr$6$(not in LMFDB)