Properties

Label 2.169.aca_bna
Base field $\F_{13^{2}}$
Dimension $2$
$p$-rank $0$
Ordinary no
Supersingular yes
Simple no
Geometrically simple no
Primitive no
Principally polarizable yes
Contains a Jacobian yes

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Invariants

Base field:  $\F_{13^{2}}$
Dimension:  $2$
L-polynomial:  $( 1 - 13 x )^{4}$
  $1 - 52 x + 1014 x^{2} - 8788 x^{3} + 28561 x^{4}$
Frobenius angles:  $0$, $0$, $0$, $0$
Angle rank:  $0$ (numerical)
Jacobians:  $3$

This isogeny class is not simple, not primitive, not ordinary, and supersingular. It is principally polarizable and contains a Jacobian.

Newton polygon

This isogeny class is supersingular.

$p$-rank:  $0$
Slopes:  $[1/2, 1/2, 1/2, 1/2]$

Point counts

Point counts of the abelian variety

$r$ $1$ $2$ $3$ $4$ $5$
$A(\F_{q^r})$ $20736$ $796594176$ $23255696077056$ $665323421736960000$ $19004759032135892541696$

Point counts of the curve

$r$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$ $9$ $10$
$C(\F_{q^r})$ $118$ $27886$ $4818022$ $815616478$ $137857006678$ $23298065815246$ $3937376134705222$ $665416605920256958$ $112455406909539395638$ $19004963774329365471406$

Jacobians and polarizations

This isogeny class contains the Jacobians of 3 curves (of which all are hyperelliptic), and hence is principally polarizable:

Decomposition and endomorphism algebra

All geometric endomorphisms are defined over $\F_{13^{2}}$.

Endomorphism algebra over $\F_{13^{2}}$
The isogeny class factors as 1.169.aba 2 and its endomorphism algebra is $\mathrm{M}_{2}(B)$, where $B$ is the quaternion algebra over \(\Q\) ramified at $13$ and $\infty$.

Base change

This isogeny class is not primitive. It is a base change from the following isogeny classes over subfields of $\F_{13^{2}}$.

SubfieldPrimitive Model
$\F_{13}$2.13.a_aba

Twists

Below are some of the twists of this isogeny class.

TwistExtension degreeCommon base change
2.169.a_ana$2$(not in LMFDB)
2.169.ca_bna$2$(not in LMFDB)
2.169.ba_tn$3$(not in LMFDB)

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

TwistExtension degreeCommon base change
2.169.a_ana$2$(not in LMFDB)
2.169.ca_bna$2$(not in LMFDB)
2.169.ba_tn$3$(not in LMFDB)
2.169.a_na$4$(not in LMFDB)
2.169.n_gn$5$(not in LMFDB)
2.169.aba_tn$6$(not in LMFDB)
2.169.a_a$8$(not in LMFDB)
2.169.an_gn$10$(not in LMFDB)