Properties

Label 2.157.abr_bdr
Base field $\F_{157}$
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:  $\F_{157}$
Dimension:  $2$
L-polynomial:  $1 - 43 x + 771 x^{2} - 6751 x^{3} + 24649 x^{4}$
Frobenius angles:  $\pm0.101717076357$, $\pm0.221991051519$
Angle rank:  $2$ (numerical)
Number field:  4.0.7079373.1
Galois group:  $D_{4}$
Jacobians:  $28$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $18627$ $600068805$ $14974910302527$ $369164672104683525$ $9099116931647620166352$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $115$ $24343$ $3869593$ $607605259$ $95389590430$ $14976078359191$ $2351243321107201$ $369145194660056371$ $57955795547488062091$ $9099059901082870732918$

Jacobians and polarizations

This isogeny class contains the Jacobians of 28 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{157}$.

Endomorphism algebra over $\F_{157}$
The endomorphism algebra of this simple isogeny class is 4.0.7079373.1.

Base change

This is a primitive isogeny class.

Twists

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

TwistExtension degreeCommon base change
2.157.br_bdr$2$(not in LMFDB)