Properties

Label 2.211.aca_bqg
Base field $\F_{211}$
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:  $\F_{211}$
Dimension:  $2$
L-polynomial:  $( 1 - 26 x + 211 x^{2} )^{2}$
  $1 - 52 x + 1098 x^{2} - 10972 x^{3} + 44521 x^{4}$
Frobenius angles:  $\pm0.147206137144$, $\pm0.147206137144$
Angle rank:  $1$ (numerical)
Jacobians:  $32$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $34596$ $1959655824$ $88224954838596$ $3928894709878785024$ $174914723241827175291876$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $160$ $44014$ $9391696$ $1982168494$ $418228949200$ $88245974708638$ $18619893805837120$ $3928797485115580894$ $828976268000541832576$ $174913992535554624347854$

Jacobians and polarizations

This isogeny class contains the Jacobians of 32 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{211}$.

Endomorphism algebra over $\F_{211}$
The isogeny class factors as 1.211.aba 2 and its endomorphism algebra is $\mathrm{M}_{2}($\(\Q(\sqrt{-42}) \)$)$

Base change

This is a primitive isogeny class.

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.211.a_aju$2$(not in LMFDB)
2.211.ca_bqg$2$(not in LMFDB)
2.211.ba_rx$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.211.a_aju$2$(not in LMFDB)
2.211.ca_bqg$2$(not in LMFDB)
2.211.ba_rx$3$(not in LMFDB)
2.211.a_ju$4$(not in LMFDB)
2.211.aba_rx$6$(not in LMFDB)