Properties

Label 2.157.abs_bem
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:  $1 - 44 x + 792 x^{2} - 6908 x^{3} + 24649 x^{4}$
Frobenius angles:  $\pm0.0704014652185$, $\pm0.215142566842$
Angle rank:  $2$ (numerical)
Number field:  4.0.4278528.1
Galois group:  $D_{4}$
Jacobians:  $20$

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

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $18490$ $598965060$ $14970795655930$ $369153343166019600$ $9099090745666998205450$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $114$ $24298$ $3868530$ $607586614$ $95389315914$ $14976074690746$ $2351243273519898$ $369145194035200606$ $57955795539305040690$ $9099059900983880740618$

Jacobians and polarizations

This isogeny class contains the Jacobians of 20 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 4.0.4278528.1.

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.bs_bem$2$(not in LMFDB)